fixed metadata hooks

Signed-off-by: Vasiliy Tolstov <v.tolstov@unistack.org>

.gitea/workflows/job_coverage.yml

@@ -0,0 +1,51 @@
+name: coverage
+
+on:
+  push:
+    branches: [ main, v3, v4 ]
+  pull_request:
+    branches: [ main, v3, v4 ]
+  # Allows you to run this workflow manually from the Actions tab
+  workflow_dispatch:
+
+jobs:
+
+  build:
+    runs-on: ubuntu-latest
+    steps:
+    - name: checkout code
+      uses: actions/checkout@v4
+      with:
+        filter: 'blob:none'
+
+    - name: setup go
+      uses: actions/setup-go@v5
+      with:
+        cache-dependency-path: "**/*.sum"
+        go-version: 'stable' 
+
+    - name: test coverage
+      run: |
+        go test -v -cover ./... -covermode=count -coverprofile coverage.out -coverpkg ./...
+        go tool cover -func coverage.out -o coverage.out
+
+    - name: coverage badge
+      uses: tj-actions/coverage-badge-go@v2
+      with:
+        green: 80
+        filename: coverage.out
+
+    - uses: stefanzweifel/git-auto-commit-action@v4
+      name: autocommit
+      with:
+        commit_message: Apply Code Coverage Badge
+        skip_fetch: true
+        skip_checkout: true
+        file_pattern: ./README.md
+
+    - name: push
+      if: steps.auto-commit-action.outputs.changes_detected == 'true'
+      uses: ad-m/github-push-action@master
+      with:
+        github_token: ${{ github.token }}
+        branch: ${{ github.ref }}

.gitea/workflows/job_lint.yml

@@ -0,0 +1,29 @@
+name: lint
+
+on:
+  pull_request:
+    types: [opened, reopened, synchronize]
+    branches:
+    - master
+    - v3
+    - v4
+
+jobs:
+  lint:
+    runs-on: ubuntu-latest
+    steps:
+    - name: checkout code
+      uses: actions/checkout@v4
+      with:
+        filter: 'blob:none'
+    - name: setup go
+      uses: actions/setup-go@v5
+      with:
+        cache-dependency-path: "**/*.sum"
+        go-version: 'stable' 
+    - name: setup deps
+      run: go get -v ./...
+    - name: run lint
+      uses: https://github.com/golangci/golangci-lint-action@v6
+      with:
+        version: 'latest'

.gitea/workflows/job_test.yml

@@ -0,0 +1,34 @@
+name: test
+
+on:
+  pull_request:
+    types: [opened, reopened, synchronize]
+    branches:
+    - master
+    - v3
+    - v4
+  push:
+    branches:
+    - master
+    - v3
+    - v4
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    steps:
+    - name: checkout code
+      uses: actions/checkout@v4
+      with:
+        filter: 'blob:none'
+    - name: setup go
+      uses: actions/setup-go@v5
+      with:
+        cache-dependency-path: "**/*.sum"
+        go-version: 'stable'
+    - name: setup deps
+      run: go get -v ./...
+    - name: run test
+      env:
+        INTEGRATION_TESTS: yes
+      run: go test -mod readonly -v ./...

.gitea/workflows/job_tests.yml

@@ -0,0 +1,53 @@
+name: test
+
+on:
+  pull_request:
+    types: [opened, reopened, synchronize]
+    branches:
+    - master
+    - v3
+    - v4
+  push:
+    branches:
+    - master
+    - v3
+    - v4
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    steps:
+    - name: checkout code
+      uses: actions/checkout@v4
+      with:
+        filter: 'blob:none'
+    - name: checkout tests
+      uses: actions/checkout@v4
+      with:
+        ref: master
+        filter: 'blob:none'
+        repository: unistack-org/micro-tests
+        path: micro-tests
+    - name: setup go
+      uses: actions/setup-go@v5
+      with:
+        cache-dependency-path: "**/*.sum"
+        go-version: 'stable'
+    - name: setup go work
+      env:
+        GOWORK: /workspace/${{ github.repository_owner }}/go.work
+      run: |
+        go work init
+        go work use .
+        go work use micro-tests
+    - name: setup deps
+      env:
+        GOWORK: /workspace/${{ github.repository_owner }}/go.work
+      run: go get -v ./...
+    - name: run tests
+      env:
+        INTEGRATION_TESTS: yes
+        GOWORK: /workspace/${{ github.repository_owner }}/go.work
+      run: |
+        cd micro-tests
+        go test -mod readonly -v ./... || true

.gitea/workflows/lint.yml

@@ -1,24 +0,0 @@
-name: lint
-on:
-  pull_request:
-    branches:
-    - master
-    - v3
-jobs:
-  lint:
-    name: lint
-    runs-on: ubuntu-latest
-    steps:
-    - name: setup-go
-      uses: https://gitea.com/actions/setup-go@v3
-      with:
-        go-version: 1.18
-    - name: checkout
-      uses: https://gitea.com/actions/checkout@v3
-    - name: deps
-      run: go get -v -d ./...
-    - name: lint
-      uses: https://github.com/golangci/golangci-lint-action@v3.4.0
-      continue-on-error: true
-      with:
-        version: v1.52

.gitea/workflows/pr.yml

@@ -1,23 +0,0 @@
-name: pr
-on:
-  pull_request:
-    branches:
-    - master
-    - v3
-jobs:
-  test:
-    name: test
-    runs-on: ubuntu-latest
-    steps:
-    - name: checkout
-      uses: https://gitea.com/actions/checkout@v3
-    - name: setup-go
-      uses: https://gitea.com/actions/setup-go@v3
-      with:
-        go-version: 1.18
-    - name: deps
-      run: go get -v -t -d ./...
-    - name: test
-      env:
-        INTEGRATION_TESTS: yes
-      run: go test -mod readonly -v ./...

.gitignore

@@ -1,6 +1,8 @@
 # Develop tools
 /.vscode/
 /.idea/
+.idea
+.vscode
 
 # Binaries for programs and plugins
 *.exe
@@ -13,6 +15,7 @@
 _obj
 _test
 _build
+.DS_Store
 
 # Architecture specific extensions/prefixes
 *.[568vq]

.golangci.yml

@@ -1,44 +1,5 @@
 run:
-  concurrency: 4
+  concurrency: 8
   deadline: 5m
   issues-exit-code: 1
   tests: true
-
-linters-settings:
-  govet:
-    check-shadowing: true
-    enable:
-      - fieldalignment
-
-linters:
-  enable:
-    - govet
-    - deadcode
-    - errcheck
-    - govet
-    - ineffassign
-    - staticcheck
-    - structcheck
-    - typecheck
-    - unused
-    - varcheck
-    - bodyclose
-    - gci
-    - goconst
-    - gocritic
-    - gosimple
-    - gofmt
-    - gofumpt
-    - goimports
-    - revive
-    - gosec
-    - makezero
-    - misspell
-    - nakedret
-    - nestif
-    - nilerr
-    - noctx
-    - prealloc
-    - unconvert
-    - unparam
-  disable-all: false

README.md

@@ -1,4 +1,9 @@
-# Micro [![License](https://img.shields.io/:license-apache-blue.svg)](https://opensource.org/licenses/Apache-2.0) [![Doc](https://img.shields.io/badge/go.dev-reference-007d9c?logo=go&logoColor=white&style=flat-square)](https://pkg.go.dev/go.unistack.org/micro/v4?tab=overview) [![Status](https://github.com/unistack-org/micro/workflows/build/badge.svg?branch=master)](https://github.com/unistack-org/micro/actions?query=workflow%3Abuild+branch%3Amaster+event%3Apush) [![Lint](https://goreportcard.com/badge/go.unistack.org/micro/v4)](https://goreportcard.com/report/go.unistack.org/micro/v4) [![Coverage](https://codecov.io/gh/unistack-org/micro/branch/v4/graph/badge.svg?token=OZPO2LP7VS)](https://codecov.io/gh/unistack-org/micro)
+# Micro
+![Coverage](https://img.shields.io/badge/Coverage-44.3%25-yellow)
+[![License](https://img.shields.io/:license-apache-blue.svg)](https://opensource.org/licenses/Apache-2.0)
+[![Doc](https://img.shields.io/badge/go.dev-reference-007d9c?logo=go&logoColor=white&style=flat-square)](https://pkg.go.dev/go.unistack.org/micro/v4?tab=overview)
+[![Status](https://git.unistack.org/unistack-org/micro/actions/workflows/job_tests.yml/badge.svg?branch=v4)](https://git.unistack.org/unistack-org/micro/actions?query=workflow%3Abuild+branch%3Av4+event%3Apush)
+[![Lint](https://goreportcard.com/badge/go.unistack.org/micro/v4)](https://goreportcard.com/report/go.unistack.org/micro/v4)
 
 Micro is a standard library for microservices.
 
@@ -10,30 +15,20 @@ Micro provides the core requirements for distributed systems development includi
 
 Micro abstracts away the details of distributed systems. Here are the main features.
 
-- **Authentication** - Auth is built in as a first class citizen. Authentication and authorization enable secure 
-zero trust networking by providing every service an identity and certificates. This additionally includes rule 
-based access control.
-
 - **Dynamic Config** - Load and hot reload dynamic config from anywhere. The config interface provides a way to load application 
-level config from any source such as env vars, file, etcd. You can merge the sources and even define fallbacks.
+level config from any source such as env vars, cmdline, file, consul, vault... You can merge the sources and even define fallbacks.
 
 - **Data Storage** - A simple data store interface to read, write and delete records. It includes support for memory, file and 
-CockroachDB by default. State and persistence becomes a core requirement beyond prototyping and Micro looks to build that into the framework.
+s3. State and persistence becomes a core requirement beyond prototyping and Micro looks to build that into the framework.
 
 - **Service Discovery** - Automatic service registration and name resolution. Service discovery is at the core of micro service 
 development. When service A needs to speak to service B it needs the location of that service.
 
-- **Load Balancing** - Client side load balancing built on service discovery. Once we have the addresses of any number of instances 
-of a service we now need a way to decide which node to route to. We use random hashed load balancing to provide even distribution 
-across the services and retry a different node if there's a problem. 
-
 - **Message Encoding** - Dynamic message encoding based on content-type. The client and server will use codecs along with content-type 
 to seamlessly encode and decode Go types for you. Any variety of messages could be encoded and sent from different clients. The client 
 and server handle this by default.
 
-- **Transport** - gRPC or http based request/response with support for bidirectional streaming. We provide an abstraction for synchronous communication. A request made to a service will be automatically resolved, load balanced, dialled and streamed.
+- **Async Messaging** - Pub/Sub is built in as a first class citizen for asynchronous communication and event driven architectures.
-
-- **Async Messaging** - PubSub is built in as a first class citizen for asynchronous communication and event driven architectures.
 Event notifications are a core pattern in micro service development.
 
 - **Synchronization** - Distributed systems are often built in an eventually consistent manner. Support for distributed locking and 
@@ -42,10 +37,6 @@ leadership are built in as a Sync interface. When using an eventually consistent
 - **Pluggable Interfaces** - Micro makes use of Go interfaces for each system abstraction. Because of this these interfaces 
 are pluggable and allows Micro to be runtime agnostic.
 
-## Getting Started
-
-To be created.
-
 ## License
 
 Micro is Apache 2.0 licensed.

broker/broker.go

@@ -1,12 +1,13 @@
 // Package broker is an interface used for asynchronous messaging
-package broker // import "go.unistack.org/micro/v4/broker"
+package broker
 
 import (
 	"context"
 	"errors"
+	"time"
 
+	"go.unistack.org/micro/v4/codec"
 	"go.unistack.org/micro/v4/metadata"
-	"go.unistack.org/micro/v4/options"
 )
 
 // DefaultBroker default memory broker
@@ -17,8 +18,12 @@ var (
 	ErrNotConnected = errors.New("broker not connected")
 	// ErrDisconnected returns when broker disconnected
 	ErrDisconnected = errors.New("broker disconnected")
-	// ErrInvalidMessage returns when message has nvalid format
+	// ErrInvalidMessage returns when invalid Message passed
-	ErrInvalidMessage = errors.New("broker message has invalid format")
+	ErrInvalidMessage = errors.New("invalid message")
+	// ErrInvalidHandler returns when subscriber passed to Subscribe
+	ErrInvalidHandler = errors.New("invalid handler, ony func(Message) error and func([]Message) error supported")
+	// DefaultGracefulTimeout
+	DefaultGracefulTimeout = 5 * time.Second
 )
 
 // Broker is an interface used for asynchronous messaging.
@@ -26,7 +31,7 @@ type Broker interface {
 	// Name returns broker instance name
 	Name() string
 	// Init initilize broker
-	Init(opts ...options.Option) error
+	Init(opts ...Option) error
 	// Options returns broker options
 	Options() Options
 	// Address return configured address
@@ -35,29 +40,44 @@ type Broker interface {
 	Connect(ctx context.Context) error
 	// Disconnect disconnect from broker
 	Disconnect(ctx context.Context) error
-	// Publish message, msg can be single broker.Message or []broker.Message
+	// NewMessage create new broker message to publish.
-	Publish(ctx context.Context, msg interface{}, opts ...options.Option) error
+	NewMessage(ctx context.Context, hdr metadata.Metadata, body interface{}, opts ...PublishOption) (Message, error)
+	// Publish message to broker topic
+	Publish(ctx context.Context, topic string, messages ...Message) error
 	// Subscribe subscribes to topic message via handler
-	Subscribe(ctx context.Context, topic string, handler interface{}, opts ...options.Option) (Subscriber, error)
+	Subscribe(ctx context.Context, topic string, handler interface{}, opts ...SubscribeOption) (Subscriber, error)
 	// String type of broker
 	String() string
+	// Live returns broker liveness
+	Live() bool
+	// Ready returns broker readiness
+	Ready() bool
+	// Health returns broker health
+	Health() bool
 }
 
+type (
+	FuncPublish   func(ctx context.Context, topic string, messages ...Message) error
+	HookPublish   func(next FuncPublish) FuncPublish
+	FuncSubscribe func(ctx context.Context, topic string, handler interface{}, opts ...SubscribeOption) (Subscriber, error)
+	HookSubscribe func(next FuncSubscribe) FuncSubscribe
+)
+
 // Message is given to a subscription handler for processing
 type Message interface {
-	// Context for the message
+	// Context for the message.
 	Context() context.Context
-	// Topic
+	// Topic returns message destination topic.
 	Topic() string
-	// Header returns message headers
+	// Header returns message headers.
 	Header() metadata.Metadata
-	// Body returns broker message may be []byte slice or some go struct
+	// Body returns broker message []byte slice
-	Body() interface{}
+	Body() []byte
-	// Ack acknowledge message
+	// Unmarshal try to decode message body to dst.
+	// This is helper method that uses codec.Unmarshal.
+	Unmarshal(dst interface{}, opts ...codec.Option) error
+	// Ack acknowledge message if supported.
 	Ack() error
-	// Error returns message error (like decoding errors or some other)
-	// In this case Body contains raw []byte from broker
-	Error() error
 }
 
 // Subscriber is a convenience return type for the Subscribe method
@@ -69,9 +89,3 @@ type Subscriber interface {
 	// Unsubscribe from topic
 	Unsubscribe(ctx context.Context) error
 }
-
-// MessageHandler func signature for single message processing
-type MessageHandler func(Message) error
-
-// MessagesHandler func signature for batch message processing
-type MessagesHandler func([]Message) error

broker/context.go

@@ -15,6 +15,15 @@ func FromContext(ctx context.Context) (Broker, bool) {
 	return c, ok
 }
 
+// MustContext returns broker from passed context
+func MustContext(ctx context.Context) Broker {
+	b, ok := FromContext(ctx)
+	if !ok {
+		panic("missing broker")
+	}
+	return b
+}
+
 // NewContext savess broker in context
 func NewContext(ctx context.Context, s Broker) context.Context {
 	if ctx == nil {
@@ -22,3 +31,33 @@ func NewContext(ctx context.Context, s Broker) context.Context {
 	}
 	return context.WithValue(ctx, brokerKey{}, s)
 }
+
+// SetSubscribeOption returns a function to setup a context with given value
+func SetSubscribeOption(k, v interface{}) SubscribeOption {
+	return func(o *SubscribeOptions) {
+		if o.Context == nil {
+			o.Context = context.Background()
+		}
+		o.Context = context.WithValue(o.Context, k, v)
+	}
+}
+
+// SetPublishOption returns a function to setup a context with given value
+func SetPublishOption(k, v interface{}) PublishOption {
+	return func(o *PublishOptions) {
+		if o.Context == nil {
+			o.Context = context.Background()
+		}
+		o.Context = context.WithValue(o.Context, k, v)
+	}
+}
+
+// SetOption returns a function to setup a context with given value
+func SetOption(k, v interface{}) Option {
+	return func(o *Options) {
+		if o.Context == nil {
+			o.Context = context.Background()
+		}
+		o.Context = context.WithValue(o.Context, k, v)
+	}
+}

broker/context_test.go

@@ -37,3 +37,25 @@ func TestNewNilContext(t *testing.T) {
 		t.Fatal("NewContext not works")
 	}
 }
+
+func TestSetSubscribeOption(t *testing.T) {
+	type key struct{}
+	o := SetSubscribeOption(key{}, "test")
+	opts := &SubscribeOptions{}
+	o(opts)
+
+	if v, ok := opts.Context.Value(key{}).(string); !ok || v == "" {
+		t.Fatal("SetSubscribeOption not works")
+	}
+}
+
+func TestSetOption(t *testing.T) {
+	type key struct{}
+	o := SetOption(key{}, "test")
+	opts := &Options{}
+	o(opts)
+
+	if v, ok := opts.Context.Value(key{}).(string); !ok || v == "" {
+		t.Fatal("SetOption not works")
+	}
+}

broker/memory.go

@@ -1,334 +0,0 @@
-package broker
-
-import (
-	"context"
-	"fmt"
-	"sync"
-	"time"
-
-	"go.unistack.org/micro/v4/codec"
-	"go.unistack.org/micro/v4/logger"
-	"go.unistack.org/micro/v4/metadata"
-	"go.unistack.org/micro/v4/options"
-	"go.unistack.org/micro/v4/semconv"
-	maddr "go.unistack.org/micro/v4/util/addr"
-	"go.unistack.org/micro/v4/util/id"
-	mnet "go.unistack.org/micro/v4/util/net"
-	"go.unistack.org/micro/v4/util/rand"
-)
-
-type MemoryBroker struct {
-	subscribers map[string][]*memorySubscriber
-	addr        string
-	opts        Options
-	sync.RWMutex
-	connected bool
-}
-
-func (m *MemoryBroker) Options() Options {
-	return m.opts
-}
-
-func (m *MemoryBroker) Address() string {
-	return m.addr
-}
-
-func (m *MemoryBroker) Connect(ctx context.Context) error {
-	m.Lock()
-	defer m.Unlock()
-
-	if m.connected {
-		return nil
-	}
-
-	// use 127.0.0.1 to avoid scan of all network interfaces
-	addr, err := maddr.Extract("127.0.0.1")
-	if err != nil {
-		return err
-	}
-	var rng rand.Rand
-	i := rng.Intn(20000)
-	// set addr with port
-	addr = mnet.HostPort(addr, 10000+i)
-
-	m.addr = addr
-	m.connected = true
-
-	return nil
-}
-
-func (m *MemoryBroker) Disconnect(ctx context.Context) error {
-	m.Lock()
-	defer m.Unlock()
-
-	select {
-	case <-ctx.Done():
-		return ctx.Err()
-	default:
-		if m.connected {
-			m.connected = false
-		}
-	}
-
-	return nil
-}
-
-func (m *MemoryBroker) Init(opts ...options.Option) error {
-	var err error
-	for _, o := range opts {
-		if err = o(&m.opts); err != nil {
-			return err
-		}
-	}
-	return nil
-}
-
-func (m *MemoryBroker) Publish(ctx context.Context, message interface{}, opts ...options.Option) error {
-	m.RLock()
-	if !m.connected {
-		m.RUnlock()
-		return ErrNotConnected
-	}
-	m.RUnlock()
-
-	var err error
-
-	select {
-	case <-ctx.Done():
-		return ctx.Err()
-	default:
-		options := NewPublishOptions(opts...)
-		var msgs []Message
-		switch v := message.(type) {
-		case []Message:
-			msgs = v
-		case Message:
-			msgs = append(msgs, v)
-		default:
-			return ErrInvalidMessage
-		}
-		msgTopicMap := make(map[string][]*memoryMessage)
-		for _, msg := range msgs {
-			p := &memoryMessage{opts: options}
-			p.topic, _ = msg.Header().Get(metadata.HeaderTopic)
-			if v, ok := msg.Body().(*codec.Frame); ok {
-				p.body = msg.Body()
-			} else if len(m.opts.Codecs) == 0 {
-				p.body = msg.Body()
-			} else {
-				cf, ok := m.opts.Codecs[options.ContentType]
-				if !ok {
-					return fmt.Errorf("%s: %s", codec.ErrUnknownContentType, options.ContentType)
-				}
-				p.body, err = cf.Marshal(v)
-				if err != nil {
-					return err
-				}
-			}
-			msgTopicMap[p.topic] = append(msgTopicMap[p.topic], p)
-		}
-
-		eh := m.opts.ErrorHandler
-
-		for t, ms := range msgTopicMap {
-			ts := time.Now()
-
-			m.opts.Meter.Counter(semconv.PublishMessageInflight, "endpoint", t).Add(len(ms))
-			m.opts.Meter.Counter(semconv.SubscribeMessageInflight, "endpoint", t).Add(len(ms))
-
-			m.RLock()
-			subs, ok := m.subscribers[t]
-			m.RUnlock()
-			if !ok {
-				m.opts.Meter.Counter(semconv.PublishMessageTotal, "endpoint", t, "status", "failure").Add(len(ms))
-				m.opts.Meter.Counter(semconv.PublishMessageInflight, "endpoint", t).Add(-len(ms))
-				m.opts.Meter.Counter(semconv.SubscribeMessageInflight, "endpoint", t).Add(-len(ms))
-				continue
-			}
-
-			m.opts.Meter.Counter(semconv.PublishMessageTotal, "endpoint", t, "status", "success").Add(len(ms))
-			for _, sub := range subs {
-				if sub.opts.ErrorHandler != nil {
-					eh = sub.opts.ErrorHandler
-				}
-
-				switch mh := sub.handler.(type) {
-				case MessagesHandler:
-					mhs := make([]Message, 0, len(ms))
-					for _, m := range ms {
-						mhs = append(mhs, m)
-					}
-					if err = mh(mhs); err != nil {
-						m.opts.Meter.Counter(semconv.SubscribeMessageTotal, "endpoint", t, "status", "failure").Add(len(ms))
-						if eh != nil {
-							switch meh := eh.(type) {
-							case MessagesHandler:
-								_ = meh(mhs)
-							case MessageHandler:
-								for _, me := range mhs {
-									_ = meh(me)
-								}
-							}
-						} else if m.opts.Logger.V(logger.ErrorLevel) {
-							m.opts.Logger.Error(m.opts.Context, err.Error())
-						}
-					}
-				case MessageHandler:
-					for _, p := range ms {
-						if err = mh(p); err != nil {
-							m.opts.Meter.Counter(semconv.SubscribeMessageTotal, "endpoint", t, "status", "failure").Inc()
-							if eh != nil {
-								switch meh := eh.(type) {
-								case MessageHandler:
-									_ = meh(p)
-								case MessagesHandler:
-									_ = meh([]Message{p})
-								}
-							} else if m.opts.Logger.V(logger.ErrorLevel) {
-								m.opts.Logger.Error(m.opts.Context, err.Error())
-							}
-						} else {
-							if sub.opts.AutoAck {
-								if err = p.Ack(); err != nil {
-									m.opts.Logger.Errorf(m.opts.Context, "ack failed: %v", err)
-									m.opts.Meter.Counter(semconv.SubscribeMessageTotal, "endpoint", t, "status", "failure").Inc()
-								} else {
-									m.opts.Meter.Counter(semconv.SubscribeMessageTotal, "endpoint", t, "status", "success").Inc()
-								}
-							} else {
-								m.opts.Meter.Counter(semconv.SubscribeMessageTotal, "endpoint", t, "status", "success").Inc()
-							}
-						}
-						m.opts.Meter.Counter(semconv.PublishMessageInflight, "endpoint", t).Add(-1)
-						m.opts.Meter.Counter(semconv.SubscribeMessageInflight, "endpoint", t).Add(-1)
-					}
-				}
-			}
-
-			te := time.Since(ts)
-			m.opts.Meter.Summary(semconv.PublishMessageLatencyMicroseconds, "endpoint", t).Update(te.Seconds())
-			m.opts.Meter.Histogram(semconv.PublishMessageDurationSeconds, "endpoint", t).Update(te.Seconds())
-			m.opts.Meter.Summary(semconv.SubscribeMessageLatencyMicroseconds, "endpoint", t).Update(te.Seconds())
-			m.opts.Meter.Histogram(semconv.SubscribeMessageDurationSeconds, "endpoint", t).Update(te.Seconds())
-		}
-
-	}
-
-	return nil
-}
-
-func (m *MemoryBroker) Subscribe(ctx context.Context, topic string, handler interface{}, opts ...options.Option) (Subscriber, error) {
-	m.RLock()
-	if !m.connected {
-		m.RUnlock()
-		return nil, ErrNotConnected
-	}
-	m.RUnlock()
-
-	sid, err := id.New()
-	if err != nil {
-		return nil, err
-	}
-
-	options := NewSubscribeOptions(opts...)
-
-	sub := &memorySubscriber{
-		exit:    make(chan bool, 1),
-		id:      sid,
-		topic:   topic,
-		handler: handler,
-		opts:    options,
-		ctx:     ctx,
-	}
-
-	m.Lock()
-	m.subscribers[topic] = append(m.subscribers[topic], sub)
-	m.Unlock()
-
-	go func() {
-		<-sub.exit
-		m.Lock()
-		newSubscribers := make([]*memorySubscriber, 0, len(m.subscribers)-1)
-		for _, sb := range m.subscribers[topic] {
-			if sb.id == sub.id {
-				continue
-			}
-			newSubscribers = append(newSubscribers, sb)
-		}
-		m.subscribers[topic] = newSubscribers
-		m.Unlock()
-	}()
-
-	return sub, nil
-}
-
-func (m *MemoryBroker) String() string {
-	return "memory"
-}
-
-func (m *MemoryBroker) Name() string {
-	return m.opts.Name
-}
-
-type memoryMessage struct {
-	err    error
-	body   interface{}
-	topic  string
-	header metadata.Metadata
-	opts   PublishOptions
-	ctx    context.Context
-}
-
-func (m *memoryMessage) Topic() string {
-	return m.topic
-}
-
-func (m *memoryMessage) Header() metadata.Metadata {
-	return m.header
-}
-
-func (m *memoryMessage) Body() interface{} {
-	return m.body
-}
-
-func (m *memoryMessage) Ack() error {
-	return nil
-}
-
-func (m *memoryMessage) Error() error {
-	return m.err
-}
-
-func (m *memoryMessage) Context() context.Context {
-	return m.ctx
-}
-
-type memorySubscriber struct {
-	ctx     context.Context
-	exit    chan bool
-	handler interface{}
-	id      string
-	topic   string
-	opts    SubscribeOptions
-}
-
-func (m *memorySubscriber) Options() SubscribeOptions {
-	return m.opts
-}
-
-func (m *memorySubscriber) Topic() string {
-	return m.topic
-}
-
-func (m *memorySubscriber) Unsubscribe(ctx context.Context) error {
-	m.exit <- true
-	return nil
-}
-
-// NewBroker return new memory broker
-func NewBroker(opts ...options.Option) *MemoryBroker {
-	return &MemoryBroker{
-		opts:        NewOptions(opts...),
-		subscribers: make(map[string][]*memorySubscriber),
-	}
-}

broker/memory/memory.go

@@ -0,0 +1,338 @@
+package broker
+
+import (
+	"context"
+	"strings"
+	"sync"
+
+	"go.unistack.org/micro/v4/broker"
+	"go.unistack.org/micro/v4/codec"
+	"go.unistack.org/micro/v4/logger"
+	"go.unistack.org/micro/v4/metadata"
+	"go.unistack.org/micro/v4/options"
+	maddr "go.unistack.org/micro/v4/util/addr"
+	"go.unistack.org/micro/v4/util/id"
+	mnet "go.unistack.org/micro/v4/util/net"
+	"go.unistack.org/micro/v4/util/rand"
+)
+
+type Broker struct {
+	funcPublish   broker.FuncPublish
+	funcSubscribe broker.FuncSubscribe
+	subscribers   map[string][]*Subscriber
+	addr          string
+	opts          broker.Options
+	sync.RWMutex
+	connected bool
+}
+
+type memoryMessage struct {
+	c     codec.Codec
+	topic string
+	ctx   context.Context
+	body  []byte
+	hdr   metadata.Metadata
+	opts  broker.PublishOptions
+}
+
+func (m *memoryMessage) Ack() error {
+	return nil
+}
+
+func (m *memoryMessage) Body() []byte {
+	return m.body
+}
+
+func (m *memoryMessage) Header() metadata.Metadata {
+	return m.hdr
+}
+
+func (m *memoryMessage) Context() context.Context {
+	return m.ctx
+}
+
+func (m *memoryMessage) Topic() string {
+	return ""
+}
+
+func (m *memoryMessage) Unmarshal(dst interface{}, opts ...codec.Option) error {
+	return m.c.Unmarshal(m.body, dst)
+}
+
+type Subscriber struct {
+	ctx     context.Context
+	exit    chan bool
+	handler interface{}
+	id      string
+	topic   string
+	opts    broker.SubscribeOptions
+}
+
+func (b *Broker) newCodec(ct string) (codec.Codec, error) {
+	if idx := strings.IndexRune(ct, ';'); idx >= 0 {
+		ct = ct[:idx]
+	}
+	b.RLock()
+	c, ok := b.opts.Codecs[ct]
+	b.RUnlock()
+	if ok {
+		return c, nil
+	}
+	return nil, codec.ErrUnknownContentType
+}
+
+func (b *Broker) Options() broker.Options {
+	return b.opts
+}
+
+func (b *Broker) Address() string {
+	return b.addr
+}
+
+func (b *Broker) Connect(ctx context.Context) error {
+	select {
+	case <-ctx.Done():
+		return ctx.Err()
+	default:
+	}
+
+	b.Lock()
+	defer b.Unlock()
+
+	if b.connected {
+		return nil
+	}
+
+	// use 127.0.0.1 to avoid scan of all network interfaces
+	addr, err := maddr.Extract("127.0.0.1")
+	if err != nil {
+		return err
+	}
+	var rng rand.Rand
+	i := rng.Intn(20000)
+	// set addr with port
+	addr = mnet.HostPort(addr, 10000+i)
+
+	b.addr = addr
+	b.connected = true
+
+	return nil
+}
+
+func (b *Broker) Disconnect(ctx context.Context) error {
+	select {
+	case <-ctx.Done():
+		return ctx.Err()
+	default:
+	}
+
+	b.Lock()
+	defer b.Unlock()
+
+	if !b.connected {
+		return nil
+	}
+
+	b.connected = false
+	return nil
+}
+
+func (b *Broker) Init(opts ...broker.Option) error {
+	for _, o := range opts {
+		o(&b.opts)
+	}
+
+	b.funcPublish = b.fnPublish
+	b.funcSubscribe = b.fnSubscribe
+
+	b.opts.Hooks.EachPrev(func(hook options.Hook) {
+		switch h := hook.(type) {
+		case broker.HookPublish:
+			b.funcPublish = h(b.funcPublish)
+		case broker.HookSubscribe:
+			b.funcSubscribe = h(b.funcSubscribe)
+		}
+	})
+
+	return nil
+}
+
+func (b *Broker) NewMessage(ctx context.Context, hdr metadata.Metadata, body interface{}, opts ...broker.PublishOption) (broker.Message, error) {
+	options := broker.NewPublishOptions(opts...)
+	m := &memoryMessage{ctx: ctx, hdr: hdr, opts: options}
+	c, err := b.newCodec(m.opts.ContentType)
+	if err == nil {
+		m.body, err = c.Marshal(body)
+	}
+	if err != nil {
+		return nil, err
+	}
+
+	return m, nil
+}
+
+func (b *Broker) Publish(ctx context.Context, topic string, messages ...broker.Message) error {
+	return b.funcPublish(ctx, topic, messages...)
+}
+
+func (b *Broker) fnPublish(ctx context.Context, topic string, messages ...broker.Message) error {
+	return b.publish(ctx, topic, messages...)
+}
+
+func (b *Broker) publish(ctx context.Context, topic string, messages ...broker.Message) error {
+	b.RLock()
+	if !b.connected {
+		b.RUnlock()
+		return broker.ErrNotConnected
+	}
+	b.RUnlock()
+
+	select {
+	case <-ctx.Done():
+		return ctx.Err()
+	default:
+	}
+
+	b.RLock()
+	subs, ok := b.subscribers[topic]
+	b.RUnlock()
+	if !ok {
+		return nil
+	}
+
+	var err error
+
+	for _, sub := range subs {
+		switch s := sub.handler.(type) {
+		default:
+			if b.opts.Logger.V(logger.ErrorLevel) {
+				b.opts.Logger.Error(ctx, "broker  handler error", broker.ErrInvalidHandler)
+			}
+		case func(broker.Message) error:
+			for _, message := range messages {
+				msg, ok := message.(*memoryMessage)
+				if !ok {
+					if b.opts.Logger.V(logger.ErrorLevel) {
+						b.opts.Logger.Error(ctx, "broker handler error", broker.ErrInvalidMessage)
+					}
+				}
+				msg.topic = topic
+				if err = s(msg); err == nil && sub.opts.AutoAck {
+					err = msg.Ack()
+				}
+				if err != nil {
+					if b.opts.Logger.V(logger.ErrorLevel) {
+						b.opts.Logger.Error(ctx, "broker handler error", err)
+					}
+				}
+			}
+		case func([]broker.Message) error:
+			if err = s(messages); err == nil && sub.opts.AutoAck {
+				for _, message := range messages {
+					err = message.Ack()
+					if err != nil {
+						if b.opts.Logger.V(logger.ErrorLevel) {
+							b.opts.Logger.Error(ctx, "broker handler error", err)
+						}
+					}
+				}
+			}
+		}
+	}
+
+	return nil
+}
+
+func (b *Broker) Subscribe(ctx context.Context, topic string, handler interface{}, opts ...broker.SubscribeOption) (broker.Subscriber, error) {
+	return b.funcSubscribe(ctx, topic, handler, opts...)
+}
+
+func (b *Broker) fnSubscribe(ctx context.Context, topic string, handler interface{}, opts ...broker.SubscribeOption) (broker.Subscriber, error) {
+	if err := broker.IsValidHandler(handler); err != nil {
+		return nil, err
+	}
+
+	b.RLock()
+	if !b.connected {
+		b.RUnlock()
+		return nil, broker.ErrNotConnected
+	}
+	b.RUnlock()
+
+	sid, err := id.New()
+	if err != nil {
+		return nil, err
+	}
+
+	options := broker.NewSubscribeOptions(opts...)
+
+	sub := &Subscriber{
+		exit:    make(chan bool, 1),
+		id:      sid,
+		topic:   topic,
+		handler: handler,
+		opts:    options,
+		ctx:     ctx,
+	}
+
+	b.Lock()
+	b.subscribers[topic] = append(b.subscribers[topic], sub)
+	b.Unlock()
+
+	go func() {
+		<-sub.exit
+		b.Lock()
+		newSubscribers := make([]*Subscriber, 0, len(b.subscribers)-1)
+		for _, sb := range b.subscribers[topic] {
+			if sb.id == sub.id {
+				continue
+			}
+			newSubscribers = append(newSubscribers, sb)
+		}
+		b.subscribers[topic] = newSubscribers
+		b.Unlock()
+	}()
+
+	return sub, nil
+}
+
+func (b *Broker) String() string {
+	return "memory"
+}
+
+func (b *Broker) Name() string {
+	return b.opts.Name
+}
+
+func (b *Broker) Live() bool {
+	return true
+}
+
+func (b *Broker) Ready() bool {
+	return true
+}
+
+func (b *Broker) Health() bool {
+	return true
+}
+
+func (m *Subscriber) Options() broker.SubscribeOptions {
+	return m.opts
+}
+
+func (m *Subscriber) Topic() string {
+	return m.topic
+}
+
+func (m *Subscriber) Unsubscribe(ctx context.Context) error {
+	m.exit <- true
+	return nil
+}
+
+// NewBroker return new memory broker
+func NewBroker(opts ...broker.Option) broker.Broker {
+	return &Broker{
+		opts:        broker.NewOptions(opts...),
+		subscribers: make(map[string][]*Subscriber),
+	}
+}

broker/memory/memory_test.go

@@ -0,0 +1,74 @@
+package broker
+
+import (
+	"context"
+	"fmt"
+	"testing"
+
+	"go.uber.org/atomic"
+	"go.unistack.org/micro/v4/broker"
+	"go.unistack.org/micro/v4/codec"
+	"go.unistack.org/micro/v4/metadata"
+)
+
+type hldr struct {
+	c atomic.Int64
+}
+
+func (h *hldr) Handler(m broker.Message) error {
+	h.c.Add(1)
+	return nil
+}
+
+func TestMemoryBroker(t *testing.T) {
+	b := NewBroker(broker.Codec("application/octet-stream", codec.NewCodec()))
+	ctx := context.Background()
+
+	if err := b.Init(); err != nil {
+		t.Fatalf("Unexpected init error %v", err)
+	}
+
+	if err := b.Connect(ctx); err != nil {
+		t.Fatalf("Unexpected connect error %v", err)
+	}
+
+	topic := "test"
+	count := int64(10)
+
+	h := &hldr{}
+
+	sub, err := b.Subscribe(ctx, topic, h.Handler)
+	if err != nil {
+		t.Fatalf("Unexpected error subscribing %v", err)
+	}
+
+	for i := int64(0); i < count; i++ {
+		message, err := b.NewMessage(ctx,
+			metadata.Pairs(
+				"foo", "bar",
+				"id", fmt.Sprintf("%d", i),
+			),
+			[]byte(`"hello world"`),
+			broker.PublishContentType("application/octet-stream"),
+		)
+		if err != nil {
+			t.Fatal(err)
+		}
+
+		if err := b.Publish(ctx, topic, message); err != nil {
+			t.Fatalf("Unexpected error publishing %d err: %v", i, err)
+		}
+	}
+
+	if err := sub.Unsubscribe(ctx); err != nil {
+		t.Fatalf("Unexpected error unsubscribing from %s: %v", topic, err)
+	}
+
+	if err := b.Disconnect(ctx); err != nil {
+		t.Fatalf("Unexpected connect error %v", err)
+	}
+
+	if h.c.Load() != count {
+		t.Fatal("invalid messages count received")
+	}
+}

broker/memory_test.go

@@ -1,107 +0,0 @@
-package broker
-
-import (
-	"context"
-	"fmt"
-	"testing"
-
-	"go.unistack.org/micro/v4/metadata"
-)
-
-func TestMemoryBatchBroker(t *testing.T) {
-	b := NewBroker()
-	ctx := context.Background()
-
-	if err := b.Connect(ctx); err != nil {
-		t.Fatalf("Unexpected connect error %v", err)
-	}
-
-	topic := "test"
-	count := 10
-
-	fn := func(evts []Message) error {
-		var err error
-		for _, evt := range evts {
-			if err = evt.Ack(); err != nil {
-				return err
-			}
-		}
-		return nil
-	}
-
-	sub, err := b.Subscribe(ctx, topic, fn)
-	if err != nil {
-		t.Fatalf("Unexpected error subscribing %v", err)
-	}
-
-	msgs := make([]Message, 0, count)
-	for i := 0; i < count; i++ {
-		message := &memoryMessage{
-			header: map[string]string{
-				metadata.HeaderTopic: topic,
-				"foo":                "bar",
-				"id":                 fmt.Sprintf("%d", i),
-			},
-			body: []byte(`"hello world"`),
-		}
-		msgs = append(msgs, message)
-	}
-
-	if err := b.Publish(ctx, msgs); err != nil {
-		t.Fatalf("Unexpected error publishing %v", err)
-	}
-
-	if err := sub.Unsubscribe(ctx); err != nil {
-		t.Fatalf("Unexpected error unsubscribing from %s: %v", topic, err)
-	}
-
-	if err := b.Disconnect(ctx); err != nil {
-		t.Fatalf("Unexpected connect error %v", err)
-	}
-}
-
-func TestMemoryBroker(t *testing.T) {
-	b := NewBroker()
-	ctx := context.Background()
-
-	if err := b.Connect(ctx); err != nil {
-		t.Fatalf("Unexpected connect error %v", err)
-	}
-
-	topic := "test"
-	count := 10
-
-	fn := func(p Message) error {
-		return p.Ack()
-	}
-
-	sub, err := b.Subscribe(ctx, topic, fn)
-	if err != nil {
-		t.Fatalf("Unexpected error subscribing %v", err)
-	}
-
-	msgs := make([]Message, 0, count)
-	for i := 0; i < count; i++ {
-		message := &memoryMessage{
-			header: map[string]string{
-				metadata.HeaderTopic: topic,
-				"foo":                "bar",
-				"id":                 fmt.Sprintf("%d", i),
-			},
-			body: []byte(`"hello world"`),
-		}
-		msgs = append(msgs, message)
-	}
-
-	if err := b.Publish(ctx, msgs); err != nil {
-		t.Fatalf("Unexpected error publishing %v", err)
-	}
-
-	if err := sub.Unsubscribe(ctx); err != nil {
-		t.Fatalf("Unexpected error unsubscribing from %s: %v", topic, err)
-	}
-
-	if err := b.Disconnect(ctx); err != nil {
-		t.Fatalf("Unexpected connect error %v", err)
-	}
-}

broker/noop.go

@@ -0,0 +1,176 @@
+package broker
+
+import (
+	"context"
+	"strings"
+	"sync"
+
+	"go.unistack.org/micro/v4/codec"
+	"go.unistack.org/micro/v4/metadata"
+	"go.unistack.org/micro/v4/options"
+)
+
+type NoopBroker struct {
+	funcPublish   FuncPublish
+	funcSubscribe FuncSubscribe
+	opts          Options
+	sync.RWMutex
+}
+
+func (b *NoopBroker) newCodec(ct string) (codec.Codec, error) {
+	if idx := strings.IndexRune(ct, ';'); idx >= 0 {
+		ct = ct[:idx]
+	}
+	b.RLock()
+	c, ok := b.opts.Codecs[ct]
+	b.RUnlock()
+	if ok {
+		return c, nil
+	}
+	return nil, codec.ErrUnknownContentType
+}
+
+func NewBroker(opts ...Option) *NoopBroker {
+	b := &NoopBroker{opts: NewOptions(opts...)}
+	b.funcPublish = b.fnPublish
+	b.funcSubscribe = b.fnSubscribe
+
+	return b
+}
+
+func (b *NoopBroker) Health() bool {
+	return true
+}
+
+func (b *NoopBroker) Live() bool {
+	return true
+}
+
+func (b *NoopBroker) Ready() bool {
+	return true
+}
+
+func (b *NoopBroker) Name() string {
+	return b.opts.Name
+}
+
+func (b *NoopBroker) String() string {
+	return "noop"
+}
+
+func (b *NoopBroker) Options() Options {
+	return b.opts
+}
+
+func (b *NoopBroker) Init(opts ...Option) error {
+	for _, opt := range opts {
+		opt(&b.opts)
+	}
+
+	b.funcPublish = b.fnPublish
+	b.funcSubscribe = b.fnSubscribe
+
+	b.opts.Hooks.EachPrev(func(hook options.Hook) {
+		switch h := hook.(type) {
+		case HookPublish:
+			b.funcPublish = h(b.funcPublish)
+		case HookSubscribe:
+			b.funcSubscribe = h(b.funcSubscribe)
+		}
+	})
+
+	return nil
+}
+
+func (b *NoopBroker) Connect(_ context.Context) error {
+	return nil
+}
+
+func (b *NoopBroker) Disconnect(_ context.Context) error {
+	return nil
+}
+
+func (b *NoopBroker) Address() string {
+	return strings.Join(b.opts.Addrs, ",")
+}
+
+type noopMessage struct {
+	c    codec.Codec
+	ctx  context.Context
+	body []byte
+	hdr  metadata.Metadata
+	opts PublishOptions
+}
+
+func (m *noopMessage) Ack() error {
+	return nil
+}
+
+func (m *noopMessage) Body() []byte {
+	return m.body
+}
+
+func (m *noopMessage) Header() metadata.Metadata {
+	return m.hdr
+}
+
+func (m *noopMessage) Context() context.Context {
+	return m.ctx
+}
+
+func (m *noopMessage) Topic() string {
+	return ""
+}
+
+func (m *noopMessage) Unmarshal(dst interface{}, opts ...codec.Option) error {
+	return m.c.Unmarshal(m.body, dst)
+}
+
+func (b *NoopBroker) NewMessage(ctx context.Context, hdr metadata.Metadata, body interface{}, opts ...PublishOption) (Message, error) {
+	options := NewPublishOptions(opts...)
+	m := &noopMessage{ctx: ctx, hdr: hdr, opts: options}
+	c, err := b.newCodec(m.opts.ContentType)
+	if err == nil {
+		m.body, err = c.Marshal(body)
+	}
+	if err != nil {
+		return nil, err
+	}
+
+	return m, nil
+}
+
+func (b *NoopBroker) fnPublish(_ context.Context, _ string, _ ...Message) error {
+	return nil
+}
+
+func (b *NoopBroker) Publish(ctx context.Context, topic string, msg ...Message) error {
+	return b.funcPublish(ctx, topic, msg...)
+}
+
+type NoopSubscriber struct {
+	ctx     context.Context
+	topic   string
+	handler interface{}
+	opts    SubscribeOptions
+}
+
+func (b *NoopBroker) fnSubscribe(ctx context.Context, topic string, handler interface{}, opts ...SubscribeOption) (Subscriber, error) {
+	return &NoopSubscriber{ctx: ctx, topic: topic, opts: NewSubscribeOptions(opts...), handler: handler}, nil
+}
+
+func (b *NoopBroker) Subscribe(ctx context.Context, topic string, handler interface{}, opts ...SubscribeOption) (Subscriber, error) {
+	return b.funcSubscribe(ctx, topic, handler, opts...)
+}
+
+func (s *NoopSubscriber) Options() SubscribeOptions {
+	return s.opts
+}
+
+func (s *NoopSubscriber) Topic() string {
+	return s.topic
+}
+
+func (s *NoopSubscriber) Unsubscribe(_ context.Context) error {
+	return nil
+}

broker/noop_test.go

@@ -0,0 +1,35 @@
+package broker
+
+import (
+	"context"
+	"testing"
+)
+
+type testHook struct {
+	f bool
+}
+
+func (t *testHook) Publish1(fn FuncPublish) FuncPublish {
+	return func(ctx context.Context, topic string, messages ...Message) error {
+		t.f = true
+		return fn(ctx, topic, messages...)
+	}
+}
+
+func TestNoopHook(t *testing.T) {
+	h := &testHook{}
+
+	b := NewBroker(Hooks(HookPublish(h.Publish1)))
+
+	if err := b.Init(); err != nil {
+		t.Fatal(err)
+	}
+
+	if err := b.Publish(context.TODO(), "", nil); err != nil {
+		t.Fatal(err)
+	}
+
+	if !h.f {
+		t.Fatal("hook not works")
+	}
+}

broker/options.go

@@ -7,20 +7,23 @@ import (
 
 	"go.unistack.org/micro/v4/codec"
 	"go.unistack.org/micro/v4/logger"
-	"go.unistack.org/micro/v4/metadata"
 	"go.unistack.org/micro/v4/meter"
 	"go.unistack.org/micro/v4/options"
 	"go.unistack.org/micro/v4/register"
+	"go.unistack.org/micro/v4/sync"
 	"go.unistack.org/micro/v4/tracer"
 )
 
 // Options struct
 type Options struct {
+	// Name holds the broker name
+	Name string
+
 	// Tracer used for tracing
 	Tracer tracer.Tracer
 	// Register can be used for clustering
 	Register register.Register
-	// Codecs holds the codec for marshal/unmarshal
+	// Codecs holds the codecs for marshal/unmarshal based on content-type
 	Codecs map[string]codec.Codec
 	// Logger used for logging
 	Logger logger.Logger
@@ -28,18 +31,24 @@ type Options struct {
 	Meter meter.Meter
 	// Context holds external options
 	Context context.Context
+
+	// Wait waits for a collection of goroutines to finish
+	Wait *sync.WaitGroup
 	// TLSConfig holds tls.TLSConfig options
 	TLSConfig *tls.Config
-	// ErrorHandler used when broker have error while processing message
+
-	ErrorHandler interface{}
+	// Addrs holds the broker address
-	// Name holds the broker name
+	Addrs []string
-	Name string
+	// Hooks can be run before broker Publish/BatchPublish and
-	// Address holds the broker address
+	// Subscribe/BatchSubscribe methods
-	Address []string
+	Hooks options.Hooks
+
+	// GracefulTimeout contains time to wait to finish in flight requests
+	GracefulTimeout time.Duration
 }
 
 // NewOptions create new Options
-func NewOptions(opts ...options.Option) Options {
+func NewOptions(opts ...Option) Options {
 	options := Options{
 		Register:        register.DefaultRegister,
 		Logger:          logger.DefaultLogger,
@@ -47,29 +56,35 @@ func NewOptions(opts ...options.Option) Options {
 		Meter:           meter.DefaultMeter,
 		Codecs:          make(map[string]codec.Codec),
 		Tracer:          tracer.DefaultTracer,
+		GracefulTimeout: DefaultGracefulTimeout,
 	}
+
 	for _, o := range opts {
 		o(&options)
 	}
 	return options
 }
 
+// Context sets the context option
+func Context(ctx context.Context) Option {
+	return func(o *Options) {
+		o.Context = ctx
+	}
+}
+
 // PublishOptions struct
 type PublishOptions struct {
-	// Context holds external options
+	// ContentType for message body
-	Context context.Context
-	// BodyOnly flag says the message contains raw body bytes
-	BodyOnly bool
-	// Message metadata usually passed as message headers
-	Metadata metadata.Metadata
-	// Content-Type of message for marshal
 	ContentType string
-	// Topic destination
+	// BodyOnly flag says the message contains raw body bytes and don't need
-	Topic string
+	// codec Marshal method
+	BodyOnly bool
+	// Context holds custom options
+	Context context.Context
 }
 
 // NewPublishOptions creates PublishOptions struct
-func NewPublishOptions(opts ...options.Option) PublishOptions {
+func NewPublishOptions(opts ...PublishOption) PublishOptions {
 	options := PublishOptions{
 		Context: context.Background(),
 	}
@@ -79,21 +94,12 @@ func NewPublishOptions(opts ...options.Option) PublishOptions {
 	return options
 }
 
-// PublishTopic pass topic for messages
-func PublishTopic(t string) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, t, ".Topic")
-	}
-}
-
 // SubscribeOptions struct
 type SubscribeOptions struct {
 	// Context holds external options
 	Context context.Context
-	// ErrorHandler used when broker have error while processing message
+	// Group holds consumer group
-	ErrorHandler interface{}
+	Group string
-	// QueueGroup holds consumer group
-	QueueGroup string
 	// AutoAck flag specifies auto ack of incoming message when no error happens
 	AutoAck bool
 	// BodyOnly flag specifies that message contains only body bytes without header
@@ -104,16 +110,137 @@ type SubscribeOptions struct {
 	BatchWait time.Duration
 }
 
-// ErrorHandler will catch all broker errors that cant be handled
+// Option func
-// in normal way, for example Codec errors
+type Option func(*Options)
-func ErrorHandler(h interface{}) options.Option {
+
-	return func(src interface{}) error {
+// PublishOption func
-		return options.Set(src, h, ".ErrorHandler")
+type PublishOption func(*PublishOptions)
+
+// PublishContentType sets message content-type that used to Marshal
+func PublishContentType(ct string) PublishOption {
+	return func(o *PublishOptions) {
+		o.ContentType = ct
 	}
 }
 
+// PublishBodyOnly publish only body of the message
+func PublishBodyOnly(b bool) PublishOption {
+	return func(o *PublishOptions) {
+		o.BodyOnly = b
+	}
+}
+
+// Addrs sets the host addresses to be used by the broker
+func Addrs(addrs ...string) Option {
+	return func(o *Options) {
+		o.Addrs = addrs
+	}
+}
+
+// Codec sets the codec used for encoding/decoding messages
+func Codec(ct string, c codec.Codec) Option {
+	return func(o *Options) {
+		o.Codecs[ct] = c
+	}
+}
+
+// SubscribeGroup sets the name of the queue to share messages on
+func SubscribeGroup(name string) SubscribeOption {
+	return func(o *SubscribeOptions) {
+		o.Group = name
+	}
+}
+
+// Register sets register option
+func Register(r register.Register) Option {
+	return func(o *Options) {
+		o.Register = r
+	}
+}
+
+// TLSConfig sets the TLS Config
+func TLSConfig(t *tls.Config) Option {
+	return func(o *Options) {
+		o.TLSConfig = t
+	}
+}
+
+// Logger sets the logger
+func Logger(l logger.Logger) Option {
+	return func(o *Options) {
+		o.Logger = l
+	}
+}
+
+// Tracer to be used for tracing
+func Tracer(t tracer.Tracer) Option {
+	return func(o *Options) {
+		o.Tracer = t
+	}
+}
+
+// Meter sets the meter
+func Meter(m meter.Meter) Option {
+	return func(o *Options) {
+		o.Meter = m
+	}
+}
+
+// Name sets the name
+func Name(n string) Option {
+	return func(o *Options) {
+		o.Name = n
+	}
+}
+
+// Hooks sets hook runs before action
+func Hooks(h ...options.Hook) Option {
+	return func(o *Options) {
+		o.Hooks = append(o.Hooks, h...)
+	}
+}
+
+// SubscribeContext set context
+func SubscribeContext(ctx context.Context) SubscribeOption {
+	return func(o *SubscribeOptions) {
+		o.Context = ctx
+	}
+}
+
+// SubscribeAutoAck contol auto acking of messages
+// after they have been handled.
+func SubscribeAutoAck(b bool) SubscribeOption {
+	return func(o *SubscribeOptions) {
+		o.AutoAck = b
+	}
+}
+
+// SubscribeBodyOnly consumes only body of the message
+func SubscribeBodyOnly(b bool) SubscribeOption {
+	return func(o *SubscribeOptions) {
+		o.BodyOnly = b
+	}
+}
+
+// SubscribeBatchSize specifies max batch size
+func SubscribeBatchSize(n int) SubscribeOption {
+	return func(o *SubscribeOptions) {
+		o.BatchSize = n
+	}
+}
+
+// SubscribeBatchWait specifies max batch wait time
+func SubscribeBatchWait(td time.Duration) SubscribeOption {
+	return func(o *SubscribeOptions) {
+		o.BatchWait = td
+	}
+}
+
+// SubscribeOption func
+type SubscribeOption func(*SubscribeOptions)
+
 // NewSubscribeOptions creates new SubscribeOptions
-func NewSubscribeOptions(opts ...options.Option) SubscribeOptions {
+func NewSubscribeOptions(opts ...SubscribeOption) SubscribeOptions {
 	options := SubscribeOptions{
 		AutoAck: true,
 		Context: context.Background(),
@@ -123,39 +250,3 @@ func NewSubscribeOptions(opts ...options.Option) SubscribeOptions {
 	}
 	return options
 }
-
-// SubscribeAutoAck contol auto acking of messages
-// after they have been handled.
-func SubscribeAutoAck(b bool) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, b, ".AutoAck")
-	}
-}
-
-// BodyOnly transfer only body without
-func BodyOnly(b bool) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, b, ".BodyOnly")
-	}
-}
-
-// SubscribeBatchSize specifies max batch size
-func SubscribeBatchSize(n int) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, n, ".BatchSize")
-	}
-}
-
-// SubscribeBatchWait specifies max batch wait time
-func SubscribeBatchWait(td time.Duration) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, td, ".BatchWait")
-	}
-}
-
-// SubscribeQueueGroup sets the shared queue name distributed messages across subscribers
-func SubscribeQueueGroup(n string) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, n, ".QueueGroup")
-	}
-}

broker/subscriber.go

@@ -1,98 +1,14 @@
 package broker
 
-import (
+// IsValidHandler func signature
-	"fmt"
+func IsValidHandler(sub interface{}) error {
-	"reflect"
+	switch sub.(type) {
-	"strings"
-	"unicode"
-	"unicode/utf8"
-)
-
-const (
-	subSig      = "func(context.Context, interface{}) error"
-	batchSubSig = "func([]context.Context, []interface{}) error"
-)
-
-// Precompute the reflect type for error. Can't use error directly
-// because Typeof takes an empty interface value. This is annoying.
-var typeOfError = reflect.TypeOf((*error)(nil)).Elem()
-
-// Is this an exported - upper case - name?
-func isExported(name string) bool {
-	rune, _ := utf8.DecodeRuneInString(name)
-	return unicode.IsUpper(rune)
-}
-
-// Is this type exported or a builtin?
-func isExportedOrBuiltinType(t reflect.Type) bool {
-	for t.Kind() == reflect.Ptr {
-		t = t.Elem()
-	}
-	// PkgPath will be non-empty even for an exported type,
-	// so we need to check the type name as well.
-	return isExported(t.Name()) || t.PkgPath() == ""
-}
-
-// ValidateSubscriber func signature
-func ValidateSubscriber(sub interface{}) error {
-	typ := reflect.TypeOf(sub)
-	var argType reflect.Type
-	switch typ.Kind() {
-	case reflect.Func:
-		name := "Func"
-		switch typ.NumIn() {
-		case 1: // func(Message) error
-
-		case 2: // func(context.Context, Message) error or func(context.Context, []Message) error
-			argType = typ.In(2)
-			// if sub.Options().Batch {
-			if argType.Kind() != reflect.Slice {
-				return fmt.Errorf("subscriber %v dont have required signature %s", name, batchSubSig)
-			}
-			if strings.Compare(fmt.Sprintf("%v", argType), "[]interface{}") == 0 {
-				return fmt.Errorf("subscriber %v dont have required signaure %s", name, batchSubSig)
-			}
-		//	}
 	default:
-			return fmt.Errorf("subscriber %v takes wrong number of args: %v required signature %s or %s", name, typ.NumIn(), subSig, batchSubSig)
+		return ErrInvalidHandler
+	case func(Message) error:
+		break
+	case func([]Message) error:
+		break
 	}
-		if !isExportedOrBuiltinType(argType) {
-			return fmt.Errorf("subscriber %v argument type not exported: %v", name, argType)
-		}
-		if typ.NumOut() != 1 {
-			return fmt.Errorf("subscriber %v has wrong number of return values: %v require signature %s or %s",
-				name, typ.NumOut(), subSig, batchSubSig)
-		}
-		if returnType := typ.Out(0); returnType != typeOfError {
-			return fmt.Errorf("subscriber %v returns %v not error", name, returnType.String())
-		}
-	default:
-		hdlr := reflect.ValueOf(sub)
-		name := reflect.Indirect(hdlr).Type().Name()
-
-		for m := 0; m < typ.NumMethod(); m++ {
-			method := typ.Method(m)
-			switch method.Type.NumIn() {
-			case 3:
-				argType = method.Type.In(2)
-			default:
-				return fmt.Errorf("subscriber %v.%v takes wrong number of args: %v required signature %s or %s",
-					name, method.Name, method.Type.NumIn(), subSig, batchSubSig)
-			}
-
-			if !isExportedOrBuiltinType(argType) {
-				return fmt.Errorf("%v argument type not exported: %v", name, argType)
-			}
-			if method.Type.NumOut() != 1 {
-				return fmt.Errorf(
-					"subscriber %v.%v has wrong number of return values: %v require signature %s or %s",
-					name, method.Name, method.Type.NumOut(), subSig, batchSubSig)
-			}
-			if returnType := method.Type.Out(0); returnType != typeOfError {
-				return fmt.Errorf("subscriber %v.%v returns %v not error", name, method.Name, returnType.String())
-			}
-		}
-	}
-
 	return nil
 }

client/backoff.go

@@ -17,13 +17,13 @@ func BackoffExp(_ context.Context, _ Request, attempts int) (time.Duration, erro
 }
 
 // BackoffInterval specifies randomization interval for backoff func
-func BackoffInterval(min time.Duration, max time.Duration) BackoffFunc {
+func BackoffInterval(minTime time.Duration, maxTime time.Duration) BackoffFunc {
 	return func(_ context.Context, _ Request, attempts int) (time.Duration, error) {
 		td := time.Duration(math.Pow(float64(attempts), math.E)) * time.Millisecond * 100
-		if td < min {
+		if td < minTime {
-			return min, nil
+			return minTime, nil
-		} else if td > max {
+		} else if td > maxTime {
-			return max, nil
+			return maxTime, nil
 		}
 		return td, nil
 	}

client/backoff_test.go

@@ -34,23 +34,23 @@ func TestBackoffExp(t *testing.T) {
 }
 
 func TestBackoffInterval(t *testing.T) {
-	min := 100 * time.Millisecond
+	minTime := 100 * time.Millisecond
-	max := 300 * time.Millisecond
+	maxTime := 300 * time.Millisecond
 
 	r := &testRequest{
 		service: "test",
 		method:  "test",
 	}
 
-	fn := BackoffInterval(min, max)
+	fn := BackoffInterval(minTime, maxTime)
 	for i := 0; i < 5; i++ {
 		d, err := fn(context.TODO(), r, i)
 		if err != nil {
 			t.Fatal(err)
 		}
 
-		if d < min || d > max {
+		if d < minTime || d > maxTime {
-			t.Fatalf("Expected %v < %v < %v", min, d, max)
+			t.Fatalf("Expected %v < %v < %v", minTime, d, maxTime)
 		}
 	}
 }

client/client.go

@@ -1,12 +1,12 @@
 // Package client is an interface for an RPC client
-package client // import "go.unistack.org/micro/v4/client"
+package client
 
 import (
 	"context"
 	"time"
 
 	"go.unistack.org/micro/v4/codec"
-	"go.unistack.org/micro/v4/options"
+	"go.unistack.org/micro/v4/metadata"
 )
 
 var (
@@ -22,8 +22,6 @@ var (
 	DefaultRetries = 0
 	// DefaultRequestTimeout is the default request timeout
 	DefaultRequestTimeout = time.Second * 5
-	// DefaultDialTimeout the default dial timeout
-	DefaultDialTimeout = time.Second * 5
 	// DefaultPoolSize sets the connection pool size
 	DefaultPoolSize = 100
 	// DefaultPoolTTL sets the connection pool ttl
@@ -31,18 +29,24 @@ var (
 )
 
 // Client is the interface used to make requests to services.
-// It supports Request/Response via Transport and Publishing via the Broker.
 // It also supports bidirectional streaming of requests.
 type Client interface {
 	Name() string
-	Init(opts ...options.Option) error
+	Init(opts ...Option) error
 	Options() Options
-	NewRequest(service string, endpoint string, req interface{}, opts ...options.Option) Request
+	NewRequest(service string, endpoint string, req interface{}, opts ...RequestOption) Request
-	Call(ctx context.Context, req Request, rsp interface{}, opts ...options.Option) error
+	Call(ctx context.Context, req Request, rsp interface{}, opts ...CallOption) error
-	Stream(ctx context.Context, req Request, opts ...options.Option) (Stream, error)
+	Stream(ctx context.Context, req Request, opts ...CallOption) (Stream, error)
 	String() string
 }
 
+type (
+	FuncCall   func(ctx context.Context, req Request, rsp interface{}, opts ...CallOption) error
+	HookCall   func(next FuncCall) FuncCall
+	FuncStream func(ctx context.Context, req Request, opts ...CallOption) (Stream, error)
+	HookStream func(next FuncStream) FuncStream
+)
+
 // Request is the interface for a synchronous request used by Call or Stream
 type Request interface {
 	// The service to call
@@ -59,22 +63,16 @@ type Request interface {
 	Codec() codec.Codec
 	// indicates whether the request will be a streaming one rather than unary
 	Stream() bool
-	// Header data
-	// Header() metadata.Metadata
 }
 
 // Response is the response received from a service
 type Response interface {
 	// Read the response
 	Codec() codec.Codec
-	// The content type
-	// ContentType() string
 	// Header data
-	// Header() metadata.Metadata
+	Header() metadata.Metadata
 	// Read the undecoded response
 	Read() ([]byte, error)
-	// The unencoded request body
-	// Body() interface{}
 }
 
 // Stream is the interface for a bidirectional synchronous stream
@@ -100,3 +98,12 @@ type Stream interface {
 	// CloseSend closes the send direction of the stream
 	CloseSend() error
 }
+
+// Option used by the Client
+type Option func(*Options)
+
+// CallOption used by Call or Stream
+type CallOption func(*CallOptions)
+
+// RequestOption used by NewRequest
+type RequestOption func(*RequestOptions)

client/client_call_options.go

@@ -2,24 +2,22 @@ package client
 
 import (
 	"context"
-
-	"go.unistack.org/micro/v4/options"
 )
 
 type clientCallOptions struct {
 	Client
-	opts []options.Option
+	opts []CallOption
 }
 
-func (s *clientCallOptions) Call(ctx context.Context, req Request, rsp interface{}, opts ...options.Option) error {
+func (s *clientCallOptions) Call(ctx context.Context, req Request, rsp interface{}, opts ...CallOption) error {
 	return s.Client.Call(ctx, req, rsp, append(s.opts, opts...)...)
 }
 
-func (s *clientCallOptions) Stream(ctx context.Context, req Request, opts ...options.Option) (Stream, error) {
+func (s *clientCallOptions) Stream(ctx context.Context, req Request, opts ...CallOption) (Stream, error) {
 	return s.Client.Stream(ctx, req, append(s.opts, opts...)...)
 }
 
 // NewClientCallOptions add CallOption to every call
-func NewClientCallOptions(c Client, opts ...options.Option) Client {
+func NewClientCallOptions(c Client, opts ...CallOption) Client {
 	return &clientCallOptions{c, opts}
 }

client/client_call_options_test.go

@@ -1,28 +0,0 @@
-package client
-
-import (
-	"context"
-	"testing"
-	"time"
-
-	"go.unistack.org/micro/v4/options"
-)
-
-func TestNewClientCallOptions(t *testing.T) {
-	var flag bool
-	w := func(fn CallFunc) CallFunc {
-		flag = true
-		return fn
-	}
-	c := NewClientCallOptions(NewClient(),
-		options.Address("127.0.0.1"),
-		WithCallWrapper(w),
-		RequestTimeout(1*time.Millisecond),
-		Retries(0),
-		Backoff(BackoffInterval(10*time.Millisecond, 100*time.Millisecond)),
-	)
-	_ = c.Call(context.TODO(), c.NewRequest("service", "endpoint", nil), nil)
-	if !flag {
-		t.Fatalf("NewClientCallOptions not works")
-	}
-}

client/context.go

@@ -15,6 +15,15 @@ func FromContext(ctx context.Context) (Client, bool) {
 	return c, ok
 }
 
+// MustContext get client from context
+func MustContext(ctx context.Context) Client {
+	c, ok := FromContext(ctx)
+	if !ok {
+		panic("missing client")
+	}
+	return c
+}
+
 // NewContext put client in context
 func NewContext(ctx context.Context, c Client) context.Context {
 	if ctx == nil {
@@ -22,3 +31,23 @@ func NewContext(ctx context.Context, c Client) context.Context {
 	}
 	return context.WithValue(ctx, clientKey{}, c)
 }
+
+// SetCallOption returns a function to setup a context with given value
+func SetCallOption(k, v interface{}) CallOption {
+	return func(o *CallOptions) {
+		if o.Context == nil {
+			o.Context = context.Background()
+		}
+		o.Context = context.WithValue(o.Context, k, v)
+	}
+}
+
+// SetOption returns a function to setup a context with given value
+func SetOption(k, v interface{}) Option {
+	return func(o *Options) {
+		if o.Context == nil {
+			o.Context = context.Background()
+		}
+		o.Context = context.WithValue(o.Context, k, v)
+	}
+}

client/context_test.go

@@ -38,3 +38,25 @@ func TestNewNilContext(t *testing.T) {
 		t.Fatal("NewContext not works")
 	}
 }
+
+func TestSetCallOption(t *testing.T) {
+	type key struct{}
+	o := SetCallOption(key{}, "test")
+	opts := &CallOptions{}
+	o(opts)
+
+	if v, ok := opts.Context.Value(key{}).(string); !ok || v == "" {
+		t.Fatal("SetCallOption not works")
+	}
+}
+
+func TestSetOption(t *testing.T) {
+	type key struct{}
+	o := SetOption(key{}, "test")
+	opts := &Options{}
+	o(opts)
+
+	if v, ok := opts.Context.Value(key{}).(string); !ok || v == "" {
+		t.Fatal("SetOption not works")
+	}
+}

client/noop.go

@@ -3,6 +3,7 @@ package client
 import (
 	"context"
 	"fmt"
+	"strconv"
 	"time"
 
 	"go.unistack.org/micro/v4/codec"
@@ -11,6 +12,7 @@ import (
 	"go.unistack.org/micro/v4/options"
 	"go.unistack.org/micro/v4/selector"
 	"go.unistack.org/micro/v4/semconv"
+	"go.unistack.org/micro/v4/tracer"
 )
 
 // DefaultCodecs will be used to encode/decode data
@@ -19,6 +21,8 @@ var DefaultCodecs = map[string]codec.Codec{
 }
 
 type noopClient struct {
+	funcCall   FuncCall
+	funcStream FuncStream
 	opts       Options
 }
 
@@ -33,13 +37,13 @@ type noopRequest struct {
 }
 
 // NewClient returns new noop client
-func NewClient(opts ...options.Option) Client {
+func NewClient(opts ...Option) Client {
-	nc := &noopClient{opts: NewOptions(opts...)}
+	n := &noopClient{opts: NewOptions(opts...)}
-	// wrap in reverse
 
-	c := Client(nc)
+	n.funcCall = n.fnCall
+	n.funcStream = n.fnStream
 
-	return c
+	return n
 }
 
 func (n *noopClient) Name() string {
@@ -91,10 +95,13 @@ func (n *noopResponse) Read() ([]byte, error) {
 	return nil, nil
 }
 
-type noopStream struct{}
+type noopStream struct {
+	err error
+	ctx context.Context
+}
 
 func (n *noopStream) Context() context.Context {
-	return context.Background()
+	return n.ctx
 }
 
 func (n *noopStream) Request() Request {
@@ -122,31 +129,40 @@ func (n *noopStream) RecvMsg(interface{}) error {
 }
 
 func (n *noopStream) Error() error {
-	return nil
+	return n.err
 }
 
 func (n *noopStream) Close() error {
-	return nil
+	if sp, ok := tracer.SpanFromContext(n.ctx); ok && sp != nil {
+		if n.err != nil {
+			sp.SetStatus(tracer.SpanStatusError, n.err.Error())
+		}
+		sp.Finish()
+	}
+	return n.err
 }
 
 func (n *noopStream) CloseSend() error {
-	return nil
+	return n.err
 }
 
-func (n *noopClient) newCodec(contentType string) (codec.Codec, error) {
+func (n *noopClient) Init(opts ...Option) error {
-	if cf, ok := n.opts.Codecs[contentType]; ok {
-		return cf, nil
-	}
-	if cf, ok := DefaultCodecs[contentType]; ok {
-		return cf, nil
-	}
-	return nil, codec.ErrUnknownContentType
-}
-
-func (n *noopClient) Init(opts ...options.Option) error {
 	for _, o := range opts {
 		o(&n.opts)
 	}
+
+	n.funcCall = n.fnCall
+	n.funcStream = n.fnStream
+
+	n.opts.Hooks.EachPrev(func(hook options.Hook) {
+		switch h := hook.(type) {
+		case HookCall:
+			n.funcCall = h(n.funcCall)
+		case HookStream:
+			n.funcStream = h(n.funcStream)
+		}
+	})
+
 	return nil
 }
 
@@ -158,7 +174,32 @@ func (n *noopClient) String() string {
 	return "noop"
 }
 
-func (n *noopClient) Call(ctx context.Context, req Request, rsp interface{}, opts ...options.Option) error {
+func (n *noopClient) Call(ctx context.Context, req Request, rsp interface{}, opts ...CallOption) error {
+	ts := time.Now()
+	n.opts.Meter.Counter(semconv.ClientRequestInflight, "endpoint", req.Endpoint()).Inc()
+	var sp tracer.Span
+	ctx, sp = n.opts.Tracer.Start(ctx, "rpc-client",
+		tracer.WithSpanKind(tracer.SpanKindClient),
+		tracer.WithSpanLabels("endpoint", req.Endpoint()),
+	)
+	err := n.funcCall(ctx, req, rsp, opts...)
+	n.opts.Meter.Counter(semconv.ClientRequestInflight, "endpoint", req.Endpoint()).Dec()
+	te := time.Since(ts)
+	n.opts.Meter.Summary(semconv.ClientRequestLatencyMicroseconds, "endpoint", req.Endpoint()).Update(te.Seconds())
+	n.opts.Meter.Histogram(semconv.ClientRequestDurationSeconds, "endpoint", req.Endpoint()).Update(te.Seconds())
+
+	if me := errors.FromError(err); me == nil {
+		sp.Finish()
+		n.opts.Meter.Counter(semconv.ClientRequestTotal, "endpoint", req.Endpoint(), "status", "success", "code", strconv.Itoa(int(200))).Inc()
+	} else {
+		sp.SetStatus(tracer.SpanStatusError, err.Error())
+		n.opts.Meter.Counter(semconv.ClientRequestTotal, "endpoint", req.Endpoint(), "status", "failure", "code", strconv.Itoa(int(me.Code))).Inc()
+	}
+
+	return err
+}
+
+func (n *noopClient) fnCall(ctx context.Context, req Request, rsp interface{}, opts ...CallOption) error {
 	// make a copy of call opts
 	callOpts := n.opts.CallOptions
 	for _, opt := range opts {
@@ -175,7 +216,7 @@ func (n *noopClient) Call(ctx context.Context, req Request, rsp interface{}, opt
 	} else {
 		// got a deadline so no need to setup context
 		// but we need to set the timeout we pass along
-		opt := RequestTimeout(time.Until(d))
+		opt := WithRequestTimeout(time.Until(d))
 		opt(&callOpts)
 	}
 
@@ -187,11 +228,8 @@ func (n *noopClient) Call(ctx context.Context, req Request, rsp interface{}, opt
 	}
 
 	// make copy of call method
-	hcall := n.call
+	hcall := func(ctx context.Context, addr string, req Request, rsp interface{}, opts CallOptions) error {
-
+		return nil
-	// wrap the call in reverse
-	for i := len(callOpts.CallWrappers); i > 0; i-- {
-		hcall = callOpts.CallWrappers[i-1](hcall)
 	}
 
 	// use the router passed as a call option, or fallback to the rpc clients router
@@ -216,7 +254,7 @@ func (n *noopClient) Call(ctx context.Context, req Request, rsp interface{}, opt
 		// call backoff first. Someone may want an initial start delay
 		t, err := callOpts.Backoff(ctx, req, i)
 		if err != nil {
-			return errors.InternalServerError("go.micro.client", err.Error())
+			return errors.InternalServerError("go.micro.client", "%s", err)
 		}
 
 		// only sleep if greater than 0
@@ -230,7 +268,7 @@ func (n *noopClient) Call(ctx context.Context, req Request, rsp interface{}, opt
 			// TODO apply any filtering here
 			routes, err = n.opts.Lookup(ctx, req, callOpts)
 			if err != nil {
-				return errors.InternalServerError("go.micro.client", err.Error())
+				return errors.InternalServerError("go.micro.client", "%s", err)
 			}
 
 			// balance the list of nodes
@@ -260,9 +298,6 @@ func (n *noopClient) Call(ctx context.Context, req Request, rsp interface{}, opt
 	ch := make(chan error, callOpts.Retries)
 	var gerr error
 
-	ts := time.Now()
-	endpoint := fmt.Sprintf("%s.%s", req.Service(), req.Endpoint())
-	n.opts.Meter.Counter(semconv.ClientRequestInflight, "endpoint", endpoint).Inc()
 	for i := 0; i <= callOpts.Retries; i++ {
 		go func() {
 			ch <- call(i)
@@ -290,28 +325,39 @@ func (n *noopClient) Call(ctx context.Context, req Request, rsp interface{}, opt
 		}
 	}
 
-	if gerr != nil {
-		n.opts.Meter.Counter(semconv.ClientRequestTotal, "endpoint", endpoint, "status", "failure").Inc()
-	} else {
-		n.opts.Meter.Counter(semconv.ClientRequestTotal, "endpoint", endpoint, "status", "success").Inc()
-	}
-	n.opts.Meter.Counter(semconv.ClientRequestInflight, "endpoint", endpoint).Dec()
-	te := time.Since(ts)
-	n.opts.Meter.Summary(semconv.ClientRequestLatencyMicroseconds, "endpoint", endpoint).Update(te.Seconds())
-	n.opts.Meter.Histogram(semconv.ClientRequestDurationSeconds, "endpoint", endpoint).Update(te.Seconds())
-
 	return gerr
 }
 
-func (n *noopClient) call(ctx context.Context, addr string, req Request, rsp interface{}, opts CallOptions) error {
+func (n *noopClient) NewRequest(service, endpoint string, _ interface{}, _ ...RequestOption) Request {
-	return nil
-}
-
-func (n *noopClient) NewRequest(service, endpoint string, req interface{}, opts ...options.Option) Request {
 	return &noopRequest{service: service, endpoint: endpoint}
 }
 
-func (n *noopClient) Stream(ctx context.Context, req Request, opts ...options.Option) (Stream, error) {
+func (n *noopClient) Stream(ctx context.Context, req Request, opts ...CallOption) (Stream, error) {
+	ts := time.Now()
+	n.opts.Meter.Counter(semconv.ClientRequestInflight, "endpoint", req.Endpoint()).Inc()
+	var sp tracer.Span
+	ctx, sp = n.opts.Tracer.Start(ctx, "rpc-client",
+		tracer.WithSpanKind(tracer.SpanKindClient),
+		tracer.WithSpanLabels("endpoint", req.Endpoint()),
+	)
+	stream, err := n.funcStream(ctx, req, opts...)
+	n.opts.Meter.Counter(semconv.ClientRequestInflight, "endpoint", req.Endpoint()).Dec()
+	te := time.Since(ts)
+	n.opts.Meter.Summary(semconv.ClientRequestLatencyMicroseconds, "endpoint", req.Endpoint()).Update(te.Seconds())
+	n.opts.Meter.Histogram(semconv.ClientRequestDurationSeconds, "endpoint", req.Endpoint()).Update(te.Seconds())
+
+	if me := errors.FromError(err); me == nil {
+		sp.Finish()
+		n.opts.Meter.Counter(semconv.ClientRequestTotal, "endpoint", req.Endpoint(), "status", "success", "code", strconv.Itoa(int(200))).Inc()
+	} else {
+		sp.SetStatus(tracer.SpanStatusError, err.Error())
+		n.opts.Meter.Counter(semconv.ClientRequestTotal, "endpoint", req.Endpoint(), "status", "failure", "code", strconv.Itoa(int(me.Code))).Inc()
+	}
+
+	return stream, err
+}
+
+func (n *noopClient) fnStream(ctx context.Context, req Request, opts ...CallOption) (Stream, error) {
 	var err error
 
 	// make a copy of call opts
@@ -330,7 +376,7 @@ func (n *noopClient) Stream(ctx context.Context, req Request, opts ...options.Op
 	} else {
 		// got a deadline so no need to setup context
 		// but we need to set the timeout we pass along
-		o := StreamTimeout(time.Until(d))
+		o := WithStreamTimeout(time.Until(d))
 		o(&callOpts)
 	}
 
@@ -371,7 +417,7 @@ func (n *noopClient) Stream(ctx context.Context, req Request, opts ...options.Op
 		// call backoff first. Someone may want an initial start delay
 		t, cerr := callOpts.Backoff(ctx, req, i)
 		if cerr != nil {
-			return nil, errors.InternalServerError("go.micro.client", cerr.Error())
+			return nil, errors.InternalServerError("go.micro.client", "%s", cerr)
 		}
 
 		// only sleep if greater than 0
@@ -385,7 +431,7 @@ func (n *noopClient) Stream(ctx context.Context, req Request, opts ...options.Op
 			// TODO apply any filtering here
 			routes, err = n.opts.Lookup(ctx, req, callOpts)
 			if err != nil {
-				return nil, errors.InternalServerError("go.micro.client", err.Error())
+				return nil, errors.InternalServerError("go.micro.client", "%s", err)
 			}
 
 			// balance the list of nodes
@@ -397,15 +443,7 @@ func (n *noopClient) Stream(ctx context.Context, req Request, opts ...options.Op
 
 		node := next()
 
-		// ts := time.Now()
-		endpoint := fmt.Sprintf("%s.%s", req.Service(), req.Endpoint())
-		n.opts.Meter.Counter(semconv.ClientRequestInflight, "endpoint", endpoint).Inc()
 		stream, cerr := n.stream(ctx, node, req, callOpts)
-		if cerr != nil {
-			n.opts.Meter.Counter(semconv.ClientRequestTotal, "endpoint", endpoint, "status", "failure").Inc()
-		} else {
-			n.opts.Meter.Counter(semconv.ClientRequestTotal, "endpoint", endpoint, "status", "success").Inc()
-		}
 
 		// record the result of the call to inform future routing decisions
 		if verr := n.opts.Selector.Record(node, cerr); verr != nil {
@@ -459,6 +497,6 @@ func (n *noopClient) Stream(ctx context.Context, req Request, opts ...options.Op
 	return nil, grr
 }
 
-func (n *noopClient) stream(ctx context.Context, addr string, req Request, opts CallOptions) (*noopStream, error) {
+func (n *noopClient) stream(ctx context.Context, _ string, _ Request, _ CallOptions) (Stream, error) {
-	return &noopStream{}, nil
+	return &noopStream{ctx: ctx}, nil
 }

client/options.go

@@ -6,11 +6,13 @@ import (
 	"net"
 	"time"
 
+	"go.unistack.org/micro/v4/broker"
 	"go.unistack.org/micro/v4/codec"
 	"go.unistack.org/micro/v4/logger"
 	"go.unistack.org/micro/v4/metadata"
 	"go.unistack.org/micro/v4/meter"
 	"go.unistack.org/micro/v4/options"
+	"go.unistack.org/micro/v4/register"
 	"go.unistack.org/micro/v4/router"
 	"go.unistack.org/micro/v4/selector"
 	"go.unistack.org/micro/v4/selector/random"
@@ -19,44 +21,56 @@ import (
 
 // Options holds client options
 type Options struct {
-	// Selector used to select needed address
-	Selector selector.Selector
-	// Logger used to log messages
-	Logger logger.Logger
-	// Tracer used for tracing
-	Tracer tracer.Tracer
-	// Meter used for metrics
-	Meter meter.Meter
-	// Context is used for external options
-	Context context.Context
-	// Router used to get route
-	Router router.Router
-	// TLSConfig specifies tls.Config for secure connection
-	TLSConfig *tls.Config
 	// Codecs map
 	Codecs map[string]codec.Codec
-	// Lookup func used to get destination addr
+
-	Lookup LookupFunc
 	// Proxy is used for proxy requests
 	Proxy string
 	// ContentType is used to select codec
 	ContentType string
 	// Name is the client name
 	Name string
+
+	// Selector used to select needed address
+	Selector selector.Selector
+	// Logger used to log messages
+	Logger logger.Logger
+	// Tracer used for tracing
+	Tracer tracer.Tracer
+	// Broker used to publish messages
+	Broker broker.Broker
+	// Meter used for metrics
+	Meter meter.Meter
+	// Context is used for external options
+	Context context.Context
+	// Router used to get route
+	Router router.Router
+
+	// TLSConfig specifies tls.Config for secure connection
+	TLSConfig *tls.Config
+
+	// Lookup func used to get destination addr
+	Lookup LookupFunc
+	// ContextDialer used to connect
+	ContextDialer func(context.Context, string) (net.Conn, error)
+
+	// Wrappers contains wrappers
+	Wrappers []Wrapper
+	// Hooks can be run before broker Publish/BatchPublish and
+	// Subscribe/BatchSubscribe methods
+	Hooks options.Hooks
+
 	// CallOptions contains default CallOptions
 	CallOptions CallOptions
+
 	// PoolSize connection pool size
 	PoolSize int
 	// PoolTTL connection pool ttl
 	PoolTTL time.Duration
-	// ContextDialer used to connect
-	ContextDialer func(context.Context, string) (net.Conn, error)
-	// Hooks may contains Client func wrapper
-	Hooks options.Hooks
 }
 
 // NewCallOptions creates new call options struct
-func NewCallOptions(opts ...options.Option) CallOptions {
+func NewCallOptions(opts ...CallOption) CallOptions {
 	options := CallOptions{}
 	for _, o := range opts {
 		o(&options)
@@ -66,6 +80,16 @@ func NewCallOptions(opts ...options.Option) CallOptions {
 
 // CallOptions holds client call options
 type CallOptions struct {
+	// RequestMetadata holds additional metadata for call
+	RequestMetadata metadata.Metadata
+
+	// Network name
+	Network string
+	// Content-Type
+	ContentType string
+	// AuthToken string
+	AuthToken string
+
 	// Selector selects addr
 	Selector selector.Selector
 	// Context used for deadline
@@ -73,46 +97,48 @@ type CallOptions struct {
 	// Router used for route
 	Router router.Router
 	// Retry func used for retries
+
+	// ResponseMetadata holds additional metadata from call
+	ResponseMetadata *metadata.Metadata
+
 	Retry RetryFunc
 	// Backoff func used for backoff when retry
 	Backoff BackoffFunc
-	// Network name
+	// ContextDialer used to connect
-	Network string
+	ContextDialer func(context.Context, string) (net.Conn, error)
-	// Content-Type
+
-	ContentType string
-	// AuthToken string
-	AuthToken string
 	// Address specifies static addr list
 	Address []string
 	// SelectOptions selector options
 	SelectOptions []selector.SelectOption
-	// CallWrappers call wrappers
+
-	CallWrappers []CallWrapper
 	// StreamTimeout stream timeout
 	StreamTimeout time.Duration
 	// RequestTimeout request timeout
 	RequestTimeout time.Duration
-	// RequestMetadata holds additional metadata for call
+
-	RequestMetadata metadata.Metadata
-	// ResponseMetadata holds additional metadata from call
-	ResponseMetadata *metadata.Metadata
 	// DialTimeout dial timeout
 	DialTimeout time.Duration
 	// Retries specifies retries num
 	Retries int
-	// ContextDialer used to connect
-	ContextDialer func(context.Context, string) (net.Conn, error)
 }
 
 // ContextDialer pass ContextDialer to client
-func ContextDialer(fn func(context.Context, string) (net.Conn, error)) options.Option {
+func ContextDialer(fn func(context.Context, string) (net.Conn, error)) Option {
-	return func(src interface{}) error {
+	return func(o *Options) {
-		return options.Set(src, fn, ".ContextDialer")
+		o.ContextDialer = fn
+	}
+}
+
+// Context pass context to client
+func Context(ctx context.Context) Option {
+	return func(o *Options) {
+		o.Context = ctx
 	}
 }
 
 // NewRequestOptions creates new RequestOptions struct
-func NewRequestOptions(opts ...options.Option) RequestOptions {
+func NewRequestOptions(opts ...RequestOption) RequestOptions {
 	options := RequestOptions{}
 	for _, o := range opts {
 		o(&options)
@@ -131,24 +157,24 @@ type RequestOptions struct {
 }
 
 // NewOptions creates new options struct
-func NewOptions(opts ...options.Option) Options {
+func NewOptions(opts ...Option) Options {
 	options := Options{
 		Context:     context.Background(),
 		ContentType: DefaultContentType,
-		Codecs:      make(map[string]codec.Codec),
+		Codecs:      DefaultCodecs,
 		CallOptions: CallOptions{
 			Context:        context.Background(),
 			Backoff:        DefaultBackoff,
 			Retry:          DefaultRetry,
 			Retries:        DefaultRetries,
 			RequestTimeout: DefaultRequestTimeout,
-			DialTimeout:    DefaultDialTimeout,
 		},
 		Lookup:   LookupRoute,
 		PoolSize: DefaultPoolSize,
 		PoolTTL:  DefaultPoolTTL,
 		Selector: random.NewSelector(),
 		Logger:   logger.DefaultLogger,
+		Broker:   broker.DefaultBroker,
 		Meter:    meter.DefaultMeter,
 		Tracer:   tracer.DefaultTracer,
 		Router:   router.DefaultRouter,
@@ -161,131 +187,284 @@ func NewOptions(opts ...options.Option) Options {
 	return options
 }
 
+// Broker to be used for pub/sub
+func Broker(b broker.Broker) Option {
+	return func(o *Options) {
+		o.Broker = b
+	}
+}
+
+// Tracer to be used for tracing
+func Tracer(t tracer.Tracer) Option {
+	return func(o *Options) {
+		o.Tracer = t
+	}
+}
+
+// Logger to be used for log mesages
+func Logger(l logger.Logger) Option {
+	return func(o *Options) {
+		o.Logger = l
+	}
+}
+
+// Meter to be used for metrics
+func Meter(m meter.Meter) Option {
+	return func(o *Options) {
+		o.Meter = m
+	}
+}
+
+// Codec to be used to encode/decode requests for a given content type
+func Codec(contentType string, c codec.Codec) Option {
+	return func(o *Options) {
+		o.Codecs[contentType] = c
+	}
+}
+
+// ContentType used by default if not specified
+func ContentType(ct string) Option {
+	return func(o *Options) {
+		o.ContentType = ct
+	}
+}
+
 // Proxy sets the proxy address
-func Proxy(addr string) options.Option {
+func Proxy(addr string) Option {
-	return func(src interface{}) error {
+	return func(o *Options) {
-		return options.Set(src, addr, ".Proxy")
+		o.Proxy = addr
 	}
 }
 
 // PoolSize sets the connection pool size
-func PoolSize(d int) options.Option {
+func PoolSize(d int) Option {
-	return func(src interface{}) error {
+	return func(o *Options) {
-		return options.Set(src, d, ".PoolSize")
+		o.PoolSize = d
 	}
 }
 
 // PoolTTL sets the connection pool ttl
-func PoolTTL(td time.Duration) options.Option {
+func PoolTTL(d time.Duration) Option {
-	return func(src interface{}) error {
+	return func(o *Options) {
-		return options.Set(src, td, ".PoolTTL")
+		o.PoolTTL = d
+	}
+}
+
+// Register sets the routers register
+func Register(r register.Register) Option {
+	return func(o *Options) {
+		if o.Router != nil {
+			_ = o.Router.Init(router.Register(r))
+		}
+	}
+}
+
+// Router is used to lookup routes for a service
+func Router(r router.Router) Option {
+	return func(o *Options) {
+		o.Router = r
 	}
 }
 
 // Selector is used to select a route
-func Selector(s selector.Selector) options.Option {
+func Selector(s selector.Selector) Option {
-	return func(src interface{}) error {
+	return func(o *Options) {
-		return options.Set(src, s, ".Selector")
+		o.Selector = s
 	}
 }
 
 // Backoff is used to set the backoff function used when retrying Calls
-func Backoff(fn BackoffFunc) options.Option {
+func Backoff(fn BackoffFunc) Option {
-	return func(src interface{}) error {
+	return func(o *Options) {
-		return options.Set(src, fn, ".Backoff")
+		o.CallOptions.Backoff = fn
+	}
+}
+
+// Name sets the client name
+func Name(n string) Option {
+	return func(o *Options) {
+		o.Name = n
 	}
 }
 
 // Lookup sets the lookup function to use for resolving service names
-func Lookup(fn LookupFunc) options.Option {
+func Lookup(l LookupFunc) Option {
-	return func(src interface{}) error {
+	return func(o *Options) {
-		return options.Set(src, fn, ".Lookup")
+		o.Lookup = l
 	}
 }
 
-// WithCallWrapper sets the retry function to be used when re-trying.
+// TLSConfig specifies a *tls.Config
-func WithCallWrapper(fn CallWrapper) options.Option {
+func TLSConfig(t *tls.Config) Option {
-	return func(src interface{}) error {
+	return func(o *Options) {
-		return options.Set(src, fn, ".CallWrappers")
+		// set the internal tls
+		o.TLSConfig = t
 	}
 }
 
 // Retries sets the retry count when making the request.
-func Retries(n int) options.Option {
+func Retries(i int) Option {
-	return func(src interface{}) error {
+	return func(o *Options) {
-		return options.Set(src, n, ".Retries")
+		o.CallOptions.Retries = i
 	}
 }
 
 // Retry sets the retry function to be used when re-trying.
-func Retry(fn RetryFunc) options.Option {
+func Retry(fn RetryFunc) Option {
-	return func(src interface{}) error {
+	return func(o *Options) {
-		return options.Set(src, fn, ".Retry")
+		o.CallOptions.Retry = fn
 	}
 }
 
 // RequestTimeout is the request timeout.
-func RequestTimeout(td time.Duration) options.Option {
+func RequestTimeout(d time.Duration) Option {
-	return func(src interface{}) error {
+	return func(o *Options) {
-		return options.Set(src, td, ".RequestTimeout")
+		o.CallOptions.RequestTimeout = d
 	}
 }
 
 // StreamTimeout sets the stream timeout
-func StreamTimeout(td time.Duration) options.Option {
+func StreamTimeout(d time.Duration) Option {
-	return func(src interface{}) error {
+	return func(o *Options) {
-		return options.Set(src, td, ".StreamTimeout")
+		o.CallOptions.StreamTimeout = d
 	}
 }
 
 // DialTimeout sets the dial timeout
-func DialTimeout(td time.Duration) options.Option {
+func DialTimeout(d time.Duration) Option {
-	return func(src interface{}) error {
+	return func(o *Options) {
-		return options.Set(src, td, ".DialTimeout")
+		o.CallOptions.DialTimeout = d
+	}
+}
+
+// WithContextDialer pass ContextDialer to client call
+func WithContextDialer(fn func(context.Context, string) (net.Conn, error)) CallOption {
+	return func(o *CallOptions) {
+		o.ContextDialer = fn
+	}
+}
+
+// WithContentType specifies call content type
+func WithContentType(ct string) CallOption {
+	return func(o *CallOptions) {
+		o.ContentType = ct
+	}
+}
+
+// WithAddress sets the remote addresses to use rather than using service discovery
+func WithAddress(a ...string) CallOption {
+	return func(o *CallOptions) {
+		o.Address = a
+	}
+}
+
+// WithBackoff is a CallOption which overrides that which
+// set in Options.CallOptions
+func WithBackoff(fn BackoffFunc) CallOption {
+	return func(o *CallOptions) {
+		o.Backoff = fn
+	}
+}
+
+// WithRetry is a CallOption which overrides that which
+// set in Options.CallOptions
+func WithRetry(fn RetryFunc) CallOption {
+	return func(o *CallOptions) {
+		o.Retry = fn
+	}
+}
+
+// WithRetries is a CallOption which overrides that which
+// set in Options.CallOptions
+func WithRetries(i int) CallOption {
+	return func(o *CallOptions) {
+		o.Retries = i
 	}
 }
 
 // WithResponseMetadata is a CallOption which adds metadata.Metadata to Options.CallOptions
-func ResponseMetadata(md *metadata.Metadata) options.Option {
+func WithResponseMetadata(md *metadata.Metadata) CallOption {
-	return func(src interface{}) error {
+	return func(o *CallOptions) {
-		return options.Set(src, md, ".ResponseMetadata")
+		o.ResponseMetadata = md
 	}
 }
 
 // WithRequestMetadata is a CallOption which adds metadata.Metadata to Options.CallOptions
-func RequestMetadata(md metadata.Metadata) options.Option {
+func WithRequestMetadata(md metadata.Metadata) CallOption {
-	return func(src interface{}) error {
+	return func(o *CallOptions) {
-		return options.Set(src, metadata.Copy(md), ".RequestMetadata")
+		o.RequestMetadata = md
 	}
 }
 
-// AuthToken is a CallOption which overrides the
+// WithRequestTimeout is a CallOption which overrides that which
+// set in Options.CallOptions
+func WithRequestTimeout(d time.Duration) CallOption {
+	return func(o *CallOptions) {
+		o.RequestTimeout = d
+	}
+}
+
+// WithStreamTimeout sets the stream timeout
+func WithStreamTimeout(d time.Duration) CallOption {
+	return func(o *CallOptions) {
+		o.StreamTimeout = d
+	}
+}
+
+// WithDialTimeout is a CallOption which overrides that which
+// set in Options.CallOptions
+func WithDialTimeout(d time.Duration) CallOption {
+	return func(o *CallOptions) {
+		o.DialTimeout = d
+	}
+}
+
+// WithAuthToken is a CallOption which overrides the
 // authorization header with the services own auth token
-func AuthToken(t string) options.Option {
+func WithAuthToken(t string) CallOption {
-	return func(src interface{}) error {
+	return func(o *CallOptions) {
-		return options.Set(src, t, ".AuthToken")
+		o.AuthToken = t
 	}
 }
 
-// Network is a CallOption which sets the network attribute
+// WithRouter sets the router to use for this call
-func Network(n string) options.Option {
+func WithRouter(r router.Router) CallOption {
-	return func(src interface{}) error {
+	return func(o *CallOptions) {
-		return options.Set(src, n, ".Network")
+		o.Router = r
+	}
+}
+
+// WithSelector sets the selector to use for this call
+func WithSelector(s selector.Selector) CallOption {
+	return func(o *CallOptions) {
+		o.Selector = s
 	}
 }
 
-/*
 // WithSelectOptions sets the options to pass to the selector for this call
-func WithSelectOptions(sops ...selector.SelectOption) options.Option {
+func WithSelectOptions(sops ...selector.SelectOption) CallOption {
 	return func(o *CallOptions) {
 		o.SelectOptions = sops
 	}
 }
-*/
 
 // StreamingRequest specifies that request is streaming
-func StreamingRequest(b bool) options.Option {
+func StreamingRequest(b bool) RequestOption {
-	return func(src interface{}) error {
+	return func(o *RequestOptions) {
-		return options.Set(src, b, ".Stream")
+		o.Stream = b
+	}
+}
+
+// RequestContentType specifies request content type
+func RequestContentType(ct string) RequestOption {
+	return func(o *RequestOptions) {
+		o.ContentType = ct
+	}
+}
+
+// Hooks sets hook runs before action
+func Hooks(h ...options.Hook) Option {
+	return func(o *Options) {
+		o.Hooks = append(o.Hooks, h...)
 	}
 }

cluster/cluster.go

@@ -0,0 +1,47 @@
+package cluster
+
+import (
+	"context"
+
+	"go.unistack.org/micro/v4/metadata"
+)
+
+// Message sent to member in cluster
+type Message interface {
+	// Header returns message headers
+	Header() metadata.Metadata
+	// Body returns broker message may be []byte slice or some go struct or interface
+	Body() interface{}
+}
+
+type Node interface {
+	// Name returns node name
+	Name() string
+	// Address returns node address
+	Address() string
+	// Metadata returns node metadata
+	Metadata() metadata.Metadata
+}
+
+// Cluster interface used for cluster communication across nodes
+type Cluster interface {
+	// Join is used to take an existing members and performing state sync
+	Join(ctx context.Context, addr ...string) error
+	// Leave broadcast a leave message and stop listeners
+	Leave(ctx context.Context) error
+	// Ping is used to probe live status of the node
+	Ping(ctx context.Context, node Node, payload []byte) error
+	// Members returns the cluster members
+	Members() ([]Node, error)
+	// Broadcast send message for all members in cluster, if filter is not nil, nodes may be filtered
+	// by key/value pairs
+	Broadcast(ctx context.Context, msg Message, filter ...string) error
+	// Unicast send message to single member in cluster
+	Unicast(ctx context.Context, node Node, msg Message) error
+	// Live returns cluster liveness
+	Live() bool
+	// Ready returns cluster readiness
+	Ready() bool
+	// Health returns cluster health
+	Health() bool
+}

codec/codec.go

@@ -1,19 +1,10 @@
 // Package codec is an interface for encoding messages
-package codec // import "go.unistack.org/micro/v4/codec"
+package codec
 
 import (
 	"errors"
-	"io"
 
-	"go.unistack.org/micro/v4/metadata"
+	"gopkg.in/yaml.v3"
-)
-
-// Message types
-const (
-	Error MessageType = iota
-	Request
-	Response
-	Event
 )
 
 var (
@@ -24,65 +15,23 @@ var (
 )
 
 var (
-	// DefaultMaxMsgSize specifies how much data codec can handle
-	DefaultMaxMsgSize = 1024 * 1024 * 4 // 4Mb
 	// DefaultCodec is the global default codec
 	DefaultCodec = NewCodec()
 	// DefaultTagName specifies struct tag name to control codec Marshal/Unmarshal
 	DefaultTagName = "codec"
 )
 
-// MessageType specifies message type for codec
+// Codec encodes/decodes various types of messages.
-type MessageType int
-
-// Codec encodes/decodes various types of messages used within micro.
-// ReadHeader and ReadBody are called in pairs to read requests/responses
-// from the connection. Close is called when finished with the
-// connection. ReadBody may be called with a nil argument to force the
-// body to be read and discarded.
 type Codec interface {
-	ReadHeader(r io.Reader, m *Message, mt MessageType) error
-	ReadBody(r io.Reader, v interface{}) error
-	Write(w io.Writer, m *Message, v interface{}) error
 	Marshal(v interface{}, opts ...Option) ([]byte, error)
 	Unmarshal(b []byte, v interface{}, opts ...Option) error
 	String() string
 }
 
-// Message represents detailed information about
+type CodecV2 interface {
-// the communication, likely followed by the body.
+	Marshal(buf []byte, v interface{}, opts ...Option) ([]byte, error)
-// In the case of an error, body may be nil.
+	Unmarshal(buf []byte, v interface{}, opts ...Option) error
-type Message struct {
+	String() string
-	Header   metadata.Metadata
-	Target   string
-	Method   string
-	Endpoint string
-	Error    string
-	ID       string
-	Body     []byte
-	Type     MessageType
-}
-
-// NewMessage creates new codec message
-func NewMessage(t MessageType) *Message {
-	return &Message{Type: t, Header: metadata.New(0)}
-}
-
-// MarshalAppend calls codec.Marshal(v) and returns the data appended to buf.
-// If codec implements MarshalAppend, that is called instead.
-func MarshalAppend(buf []byte, c Codec, v interface{}, opts ...Option) ([]byte, error) {
-	if nc, ok := c.(interface {
-		MarshalAppend([]byte, interface{}, ...Option) ([]byte, error)
-	}); ok {
-		return nc.MarshalAppend(buf, v, opts...)
-	}
-
-	mbuf, err := c.Marshal(v, opts...)
-	if err != nil {
-		return nil, err
-	}
-
-	return append(buf, mbuf...), nil
 }
 
 // RawMessage is a raw encoded JSON value.
@@ -93,6 +42,8 @@ type RawMessage []byte
 func (m *RawMessage) MarshalJSON() ([]byte, error) {
 	if m == nil {
 		return []byte("null"), nil
+	} else if len(*m) == 0 {
+		return []byte("null"), nil
 	}
 	return *m, nil
 }
@@ -105,3 +56,22 @@ func (m *RawMessage) UnmarshalJSON(data []byte) error {
 	*m = append((*m)[0:0], data...)
 	return nil
 }
+
+// MarshalYAML returns m as the JSON encoding of m.
+func (m *RawMessage) MarshalYAML() ([]byte, error) {
+	if m == nil {
+		return []byte("null"), nil
+	} else if len(*m) == 0 {
+		return []byte("null"), nil
+	}
+	return *m, nil
+}
+
+// UnmarshalYAML sets *m to a copy of data.
+func (m *RawMessage) UnmarshalYAML(n *yaml.Node) error {
+	if m == nil {
+		return errors.New("RawMessage UnmarshalYAML on nil pointer")
+	}
+	*m = append((*m)[0:0], []byte(n.Value)...)
+	return nil
+}

codec/context.go

@@ -15,6 +15,15 @@ func FromContext(ctx context.Context) (Codec, bool) {
 	return c, ok
 }
 
+// MustContext returns codec from context
+func MustContext(ctx context.Context) Codec {
+	c, ok := FromContext(ctx)
+	if !ok {
+		panic("missing codec")
+	}
+	return c
+}
+
 // NewContext put codec in context
 func NewContext(ctx context.Context, c Codec) context.Context {
 	if ctx == nil {

codec/frame.go

@@ -1,5 +1,7 @@
 package codec
 
+import "gopkg.in/yaml.v3"
+
 // Frame gives us the ability to define raw data to send over the pipes
 type Frame struct {
 	Data []byte
@@ -20,6 +22,17 @@ func (m *Frame) UnmarshalJSON(data []byte) error {
 	return m.Unmarshal(data)
 }
 
+// MarshalYAML returns frame data
+func (m *Frame) MarshalYAML() ([]byte, error) {
+	return m.Marshal()
+}
+
+// UnmarshalYAML set frame data
+func (m *Frame) UnmarshalYAML(n *yaml.Node) error {
+	m.Data = []byte(n.Value)
+	return nil
+}
+
 // ProtoMessage noop func
 func (m *Frame) ProtoMessage() {}
 

codec/frame.proto

@@ -1,4 +1,4 @@
-// Copyright 2021-2023 Unistack LLC
+// Copyright 2021 Unistack LLC
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.

codec/noop.go

@@ -2,70 +2,14 @@ package codec
 
 import (
 	"encoding/json"
-	"io"
+
+	codecpb "go.unistack.org/micro-proto/v4/codec"
 )
 
 type noopCodec struct {
 	opts Options
 }
 
-func (c *noopCodec) ReadHeader(conn io.Reader, m *Message, t MessageType) error {
-	return nil
-}
-
-func (c *noopCodec) ReadBody(conn io.Reader, b interface{}) error {
-	// read bytes
-	buf, err := io.ReadAll(conn)
-	if err != nil {
-		return err
-	}
-
-	if b == nil {
-		return nil
-	}
-
-	switch v := b.(type) {
-	case *string:
-		*v = string(buf)
-	case *[]byte:
-		*v = buf
-	case *Frame:
-		v.Data = buf
-	default:
-		return json.Unmarshal(buf, v)
-	}
-
-	return nil
-}
-
-func (c *noopCodec) Write(conn io.Writer, m *Message, b interface{}) error {
-	if b == nil {
-		return nil
-	}
-
-	var v []byte
-	switch vb := b.(type) {
-	case *Frame:
-		v = vb.Data
-	case string:
-		v = []byte(vb)
-	case *string:
-		v = []byte(*vb)
-	case *[]byte:
-		v = *vb
-	case []byte:
-		v = vb
-	default:
-		var err error
-		v, err = json.Marshal(vb)
-		if err != nil {
-			return err
-		}
-	}
-	_, err := conn.Write(v)
-	return err
-}
-
 func (c *noopCodec) String() string {
 	return "noop"
 }
@@ -91,8 +35,8 @@ func (c *noopCodec) Marshal(v interface{}, opts ...Option) ([]byte, error) {
 		return ve, nil
 	case *Frame:
 		return ve.Data, nil
-	case *Message:
+	case *codecpb.Frame:
-		return ve.Body, nil
+		return ve.Data, nil
 	}
 
 	return json.Marshal(v)
@@ -115,8 +59,8 @@ func (c *noopCodec) Unmarshal(d []byte, v interface{}, opts ...Option) error {
 	case *Frame:
 		ve.Data = d
 		return nil
-	case *Message:
+	case *codecpb.Frame:
-		ve.Body = d
+		ve.Data = d
 		return nil
 	}
 

codec/options.go

@@ -23,15 +23,8 @@ type Options struct {
 	Context context.Context
 	// TagName specifies tag name in struct to control codec
 	TagName string
-	// MaxMsgSize specifies max messages size that reads by codec
+	// Flatten specifies that struct must be analyzed for flatten tag
-	MaxMsgSize int
+	Flatten bool
-}
-
-// MaxMsgSize sets the max message size
-func MaxMsgSize(n int) Option {
-	return func(o *Options) {
-		o.MaxMsgSize = n
-	}
 }
 
 // TagName sets the codec tag name in struct
@@ -41,6 +34,13 @@ func TagName(n string) Option {
 	}
 }
 
+// Flatten enables checking for flatten tag name
+func Flatten(b bool) Option {
+	return func(o *Options) {
+		o.Flatten = b
+	}
+}
+
 // Logger sets the logger
 func Logger(l logger.Logger) Option {
 	return func(o *Options) {
@@ -69,8 +69,8 @@ func NewOptions(opts ...Option) Options {
 		Logger:  logger.DefaultLogger,
 		Meter:   meter.DefaultMeter,
 		Tracer:  tracer.DefaultTracer,
-		MaxMsgSize: DefaultMaxMsgSize,
 		TagName: DefaultTagName,
+		Flatten: false,
 	}
 
 	for _, o := range opts {

config/config.go

@@ -1,13 +1,11 @@
 // Package config is an interface for dynamic configuration.
-package config // import "go.unistack.org/micro/v4/config"
+package config
 
 import (
 	"context"
 	"errors"
 	"reflect"
 	"time"
-
-	"go.unistack.org/micro/v4/options"
 )
 
 type Validator interface {
@@ -39,19 +37,26 @@ type Config interface {
 	// Name returns name of config
 	Name() string
 	// Init the config
-	Init(opts ...options.Option) error
+	Init(opts ...Option) error
 	// Options in the config
 	Options() Options
 	// Load config from sources
-	Load(context.Context, ...options.Option) error
+	Load(context.Context, ...LoadOption) error
 	// Save config to sources
-	Save(context.Context, ...options.Option) error
+	Save(context.Context, ...SaveOption) error
 	// Watch a config for changes
-	Watch(context.Context, ...options.Option) (Watcher, error)
+	Watch(context.Context, ...WatchOption) (Watcher, error)
 	// String returns config type name
 	String() string
 }
 
+type (
+	FuncLoad func(ctx context.Context, opts ...LoadOption) error
+	HookLoad func(next FuncLoad) FuncLoad
+	FuncSave func(ctx context.Context, opts ...SaveOption) error
+	HookSave func(next FuncSave) FuncSave
+)
+
 // Watcher is the config watcher
 type Watcher interface {
 	// Next blocks until update happens or error returned
@@ -61,7 +66,7 @@ type Watcher interface {
 }
 
 // Load loads config from config sources
-func Load(ctx context.Context, cs []Config, opts ...options.Option) error {
+func Load(ctx context.Context, cs []Config, opts ...LoadOption) error {
 	var err error
 	for _, c := range cs {
 		if err = c.Init(); err != nil {
@@ -133,7 +138,7 @@ var (
 				return nil
 			}
 			if err := fn(ctx, c); err != nil {
-				c.Options().Logger.Errorf(ctx, "%s BeforeLoad err: %v", c.String(), err)
+				c.Options().Logger.Error(ctx, c.String()+" BeforeLoad error", err)
 				if !c.Options().AllowFail {
 					return err
 				}
@@ -148,7 +153,7 @@ var (
 				return nil
 			}
 			if err := fn(ctx, c); err != nil {
-				c.Options().Logger.Errorf(ctx, "%s AfterLoad err: %v", c.String(), err)
+				c.Options().Logger.Error(ctx, c.String()+" AfterLoad error", err)
 				if !c.Options().AllowFail {
 					return err
 				}
@@ -163,7 +168,7 @@ var (
 				return nil
 			}
 			if err := fn(ctx, c); err != nil {
-				c.Options().Logger.Errorf(ctx, "%s BeforeSave err: %v", c.String(), err)
+				c.Options().Logger.Error(ctx, c.String()+" BeforeSave error", err)
 				if !c.Options().AllowFail {
 					return err
 				}
@@ -178,7 +183,7 @@ var (
 				return nil
 			}
 			if err := fn(ctx, c); err != nil {
-				c.Options().Logger.Errorf(ctx, "%s AfterSave err: %v", c.String(), err)
+				c.Options().Logger.Error(ctx, c.String()+" AfterSave error", err)
 				if !c.Options().AllowFail {
 					return err
 				}
@@ -193,7 +198,7 @@ var (
 				return nil
 			}
 			if err := fn(ctx, c); err != nil {
-				c.Options().Logger.Errorf(ctx, "%s BeforeInit err: %v", c.String(), err)
+				c.Options().Logger.Error(ctx, c.String()+" BeforeInit error", err)
 				if !c.Options().AllowFail {
 					return err
 				}
@@ -208,7 +213,7 @@ var (
 				return nil
 			}
 			if err := fn(ctx, c); err != nil {
-				c.Options().Logger.Errorf(ctx, "%s AfterInit err: %v", c.String(), err)
+				c.Options().Logger.Error(ctx, c.String()+" AfterInit error", err)
 				if !c.Options().AllowFail {
 					return err
 				}

config/context.go

@@ -15,6 +15,15 @@ func FromContext(ctx context.Context) (Config, bool) {
 	return c, ok
 }
 
+// MustContext returns store from context
+func MustContext(ctx context.Context) Config {
+	c, ok := FromContext(ctx)
+	if !ok {
+		panic("missing config")
+	}
+	return c
+}
+
 // NewContext put store in context
 func NewContext(ctx context.Context, c Config) context.Context {
 	if ctx == nil {
@@ -22,3 +31,43 @@ func NewContext(ctx context.Context, c Config) context.Context {
 	}
 	return context.WithValue(ctx, configKey{}, c)
 }
+
+// SetOption returns a function to setup a context with given value
+func SetOption(k, v interface{}) Option {
+	return func(o *Options) {
+		if o.Context == nil {
+			o.Context = context.Background()
+		}
+		o.Context = context.WithValue(o.Context, k, v)
+	}
+}
+
+// SetSaveOption returns a function to setup a context with given value
+func SetSaveOption(k, v interface{}) SaveOption {
+	return func(o *SaveOptions) {
+		if o.Context == nil {
+			o.Context = context.Background()
+		}
+		o.Context = context.WithValue(o.Context, k, v)
+	}
+}
+
+// SetLoadOption returns a function to setup a context with given value
+func SetLoadOption(k, v interface{}) LoadOption {
+	return func(o *LoadOptions) {
+		if o.Context == nil {
+			o.Context = context.Background()
+		}
+		o.Context = context.WithValue(o.Context, k, v)
+	}
+}
+
+// SetWatchOption returns a function to setup a context with given value
+func SetWatchOption(k, v interface{}) WatchOption {
+	return func(o *WatchOptions) {
+		if o.Context == nil {
+			o.Context = context.Background()
+		}
+		o.Context = context.WithValue(o.Context, k, v)
+	}
+}

config/context_test.go

@@ -40,3 +40,47 @@ func TestNewContext(t *testing.T) {
 		t.Fatal("NewContext not works")
 	}
 }
+
+func TestSetOption(t *testing.T) {
+	type key struct{}
+	o := SetOption(key{}, "test")
+	opts := &Options{}
+	o(opts)
+
+	if v, ok := opts.Context.Value(key{}).(string); !ok || v == "" {
+		t.Fatal("SetOption not works")
+	}
+}
+
+func TestSetSaveOption(t *testing.T) {
+	type key struct{}
+	o := SetSaveOption(key{}, "test")
+	opts := &SaveOptions{}
+	o(opts)
+
+	if v, ok := opts.Context.Value(key{}).(string); !ok || v == "" {
+		t.Fatal("SetSaveOption not works")
+	}
+}
+
+func TestSetLoadOption(t *testing.T) {
+	type key struct{}
+	o := SetLoadOption(key{}, "test")
+	opts := &LoadOptions{}
+	o(opts)
+
+	if v, ok := opts.Context.Value(key{}).(string); !ok || v == "" {
+		t.Fatal("SetLoadOption not works")
+	}
+}
+
+func TestSetWatchOption(t *testing.T) {
+	type key struct{}
+	o := SetWatchOption(key{}, "test")
+	opts := &WatchOptions{}
+	o(opts)
+
+	if v, ok := opts.Context.Value(key{}).(string); !ok || v == "" {
+		t.Fatal("SetWatchOption not works")
+	}
+}

config/default.go

@@ -7,8 +7,8 @@ import (
 	"strings"
 	"time"
 
+	"dario.cat/mergo"
 	"github.com/google/uuid"
-	"github.com/imdario/mergo"
 	"go.unistack.org/micro/v4/options"
 	mid "go.unistack.org/micro/v4/util/id"
 	rutil "go.unistack.org/micro/v4/util/reflect"
@@ -16,6 +16,8 @@ import (
 )
 
 type defaultConfig struct {
+	funcLoad FuncLoad
+	funcSave FuncSave
 	opts     Options
 }
 
@@ -23,7 +25,7 @@ func (c *defaultConfig) Options() Options {
 	return c.opts
 }
 
-func (c *defaultConfig) Init(opts ...options.Option) error {
+func (c *defaultConfig) Init(opts ...Option) error {
 	for _, o := range opts {
 		o(&c.opts)
 	}
@@ -32,6 +34,18 @@ func (c *defaultConfig) Init(opts ...options.Option) error {
 		return err
 	}
 
+	c.funcLoad = c.fnLoad
+	c.funcSave = c.fnSave
+
+	c.opts.Hooks.EachPrev(func(hook options.Hook) {
+		switch h := hook.(type) {
+		case HookLoad:
+			c.funcLoad = h(c.funcLoad)
+		case HookSave:
+			c.funcSave = h(c.funcSave)
+		}
+	})
+
 	if err := DefaultAfterInit(c.opts.Context, c); err != nil && !c.opts.AllowFail {
 		return err
 	}
@@ -39,8 +53,18 @@ func (c *defaultConfig) Init(opts ...options.Option) error {
 	return nil
 }
 
-func (c *defaultConfig) Load(ctx context.Context, opts ...options.Option) error {
+func (c *defaultConfig) Load(ctx context.Context, opts ...LoadOption) error {
-	if err := DefaultBeforeLoad(ctx, c); err != nil && !c.opts.AllowFail {
+	return c.funcLoad(ctx, opts...)
+}
+
+func (c *defaultConfig) fnLoad(ctx context.Context, opts ...LoadOption) error {
+	var err error
+
+	if c.opts.SkipLoad != nil && c.opts.SkipLoad(ctx, c) {
+		return nil
+	}
+
+	if err = DefaultBeforeLoad(ctx, c); err != nil && !c.opts.AllowFail {
 		return err
 	}
 
@@ -230,6 +254,7 @@ func fillValue(value reflect.Value, val string) error {
 		}
 		value.Set(reflect.ValueOf(v))
 	}
+
 	return nil
 }
 
@@ -292,7 +317,15 @@ func fillValues(valueOf reflect.Value, tname string) error {
 	return nil
 }
 
-func (c *defaultConfig) Save(ctx context.Context, opts ...options.Option) error {
+func (c *defaultConfig) Save(ctx context.Context, opts ...SaveOption) error {
+	return c.funcSave(ctx, opts...)
+}
+
+func (c *defaultConfig) fnSave(ctx context.Context, opts ...SaveOption) error {
+	if c.opts.SkipSave != nil && c.opts.SkipSave(ctx, c) {
+		return nil
+	}
+
 	if err := DefaultBeforeSave(ctx, c); err != nil {
 		return err
 	}
@@ -312,15 +345,19 @@ func (c *defaultConfig) Name() string {
 	return c.opts.Name
 }
 
-func (c *defaultConfig) Watch(ctx context.Context, opts ...options.Option) (Watcher, error) {
+func (c *defaultConfig) Watch(_ context.Context, _ ...WatchOption) (Watcher, error) {
 	return nil, ErrWatcherNotImplemented
 }
 
 // NewConfig returns new default config source
-func NewConfig(opts ...options.Option) Config {
+func NewConfig(opts ...Option) Config {
 	options := NewOptions(opts...)
 	if len(options.StructTag) == 0 {
 		options.StructTag = "default"
 	}
-	return &defaultConfig{opts: options}
+	c := &defaultConfig{opts: options}
+	c.funcLoad = c.fnLoad
+	c.funcSave = c.fnSave
+
+	return c
 }

config/default_test.go

@@ -3,24 +3,26 @@ package config_test
 import (
 	"context"
 	"fmt"
+	"reflect"
 	"testing"
 	"time"
 
 	"go.unistack.org/micro/v4/config"
-	mid "go.unistack.org/micro/v4/util/id"
 	mtime "go.unistack.org/micro/v4/util/time"
 )
 
 type cfg struct {
+	MapValue    map[string]bool `default:"key1=true,key2=false"`
+	StructValue *cfgStructValue
+
 	StringValue string `default:"string_value"`
 	IgnoreValue string `json:"-"`
-	StructValue    *cfgStructValue
-	IntValue       int             `default:"99"`
-	DurationValue  time.Duration   `default:"10s"`
-	MDurationValue mtime.Duration  `default:"10s"`
-	MapValue       map[string]bool `default:"key1=true,key2=false"`
 	UUIDValue   string `default:"micro:generate uuid"`
 	IDValue     string `default:"micro:generate id"`
+
+	DurationValue  time.Duration  `default:"10s"`
+	MDurationValue mtime.Duration `default:"10s"`
+	IntValue       int            `default:"99"`
 }
 
 type cfgStructValue struct {
@@ -41,6 +43,35 @@ func (c *cfgStructValue) Validate() error {
 	return nil
 }
 
+type testHook struct {
+	f bool
+}
+
+func (t *testHook) Load(fn config.FuncLoad) config.FuncLoad {
+	return func(ctx context.Context, opts ...config.LoadOption) error {
+		t.f = true
+		return fn(ctx, opts...)
+	}
+}
+
+func TestHook(t *testing.T) {
+	h := &testHook{}
+
+	c := config.NewConfig(config.Struct(h), config.Hooks(config.HookLoad(h.Load)))
+
+	if err := c.Init(); err != nil {
+		t.Fatal(err)
+	}
+
+	if err := c.Load(context.TODO()); err != nil {
+		t.Fatal(err)
+	}
+
+	if !h.f {
+		t.Fatal("hook not works")
+	}
+}
+
 func TestDefault(t *testing.T) {
 	ctx := context.Background()
 	conf := &cfg{IntValue: 10}
@@ -83,8 +114,6 @@ func TestDefault(t *testing.T) {
 
 	if conf.IDValue == "" {
 		t.Fatalf("id value empty")
-	} else if len(conf.IDValue) != mid.DefaultSize {
-		t.Fatalf("id value invalid: %s", conf.IDValue)
 	}
 	_ = conf
 	// t.Logf("%#+v\n", conf)
@@ -105,3 +134,13 @@ func TestValidate(t *testing.T) {
 		t.Fatal(err)
 	}
 }
+
+func Test_SizeOf(t *testing.T) {
+	st := cfg{}
+
+	tVal := reflect.TypeOf(st)
+	for i := 0; i < tVal.NumField(); i++ {
+		field := tVal.Field(i)
+		fmt.Printf("Field: %s, Offset: %d, Size: %d\n", field.Name, field.Offset, field.Type.Size())
+	}
+}

config/options.go

@@ -41,12 +41,23 @@ type Options struct {
 	BeforeInit []func(context.Context, Config) error
 	// AfterInit contains slice of funcs that runs after Init
 	AfterInit []func(context.Context, Config) error
+
+	// SkipLoad runs only if condition returns true
+	SkipLoad func(context.Context, Config) bool
+	// SkipSave runs only if condition returns true
+	SkipSave func(context.Context, Config) bool
+	// Hooks can be run before/after config Save/Load
+	Hooks options.Hooks
+
 	// AllowFail flag to allow fail in config source
 	AllowFail bool
 }
 
+// Option function signature
+type Option func(o *Options)
+
 // NewOptions new options struct with filed values
-func NewOptions(opts ...options.Option) Options {
+func NewOptions(opts ...Option) Options {
 	options := Options{
 		Logger:  logger.DefaultLogger,
 		Meter:   meter.DefaultMeter,
@@ -60,16 +71,19 @@ func NewOptions(opts ...options.Option) Options {
 	return options
 }
 
+// LoadOption function signature
+type LoadOption func(o *LoadOptions)
+
 // LoadOptions struct
 type LoadOptions struct {
 	Struct   interface{}
+	Context  context.Context
 	Override bool
 	Append   bool
-	Context  context.Context
 }
 
 // NewLoadOptions create LoadOptions struct with provided opts
-func NewLoadOptions(opts ...options.Option) LoadOptions {
+func NewLoadOptions(opts ...LoadOption) LoadOptions {
 	options := LoadOptions{}
 	for _, o := range opts {
 		o(&options)
@@ -78,27 +92,44 @@ func NewLoadOptions(opts ...options.Option) LoadOptions {
 }
 
 // LoadOverride override values when load
-func LoadOverride(b bool) options.Option {
+func LoadOverride(b bool) LoadOption {
-	return func(src interface{}) error {
+	return func(o *LoadOptions) {
-		return options.Set(src, b, ".Override")
+		o.Override = b
 	}
 }
 
 // LoadAppend override values when load
-func LoadAppend(b bool) options.Option {
+func LoadAppend(b bool) LoadOption {
-	return func(src interface{}) error {
+	return func(o *LoadOptions) {
-		return options.Set(src, b, ".Append")
+		o.Append = b
 	}
 }
 
+// LoadStruct override struct for loading
+func LoadStruct(src interface{}) LoadOption {
+	return func(o *LoadOptions) {
+		o.Struct = src
+	}
+}
+
+// SaveOption function signature
+type SaveOption func(o *SaveOptions)
+
 // SaveOptions struct
 type SaveOptions struct {
 	Struct  interface{}
 	Context context.Context
 }
 
+// SaveStruct override struct for save to config
+func SaveStruct(src interface{}) SaveOption {
+	return func(o *SaveOptions) {
+		o.Struct = src
+	}
+}
+
 // NewSaveOptions fill SaveOptions struct
-func NewSaveOptions(opts ...options.Option) SaveOptions {
+func NewSaveOptions(opts ...SaveOption) SaveOptions {
 	options := SaveOptions{}
 	for _, o := range opts {
 		o(&options)
@@ -107,65 +138,100 @@ func NewSaveOptions(opts ...options.Option) SaveOptions {
 }
 
 // AllowFail allows config source to fail
-func AllowFail(b bool) options.Option {
+func AllowFail(b bool) Option {
-	return func(src interface{}) error {
+	return func(o *Options) {
-		return options.Set(src, b, ".AllowFail")
+		o.AllowFail = b
 	}
 }
 
 // BeforeInit run funcs before config Init
-func BeforeInit(fn ...func(context.Context, Config) error) options.Option {
+func BeforeInit(fn ...func(context.Context, Config) error) Option {
-	return func(src interface{}) error {
+	return func(o *Options) {
-		return options.Set(src, fn, ".BeforeInit")
+		o.BeforeInit = fn
 	}
 }
 
 // AfterInit run funcs after config Init
-func AfterInit(fn ...func(context.Context, Config) error) options.Option {
+func AfterInit(fn ...func(context.Context, Config) error) Option {
-	return func(src interface{}) error {
+	return func(o *Options) {
-		return options.Set(src, fn, ".AfterInit")
+		o.AfterInit = fn
 	}
 }
 
 // BeforeLoad run funcs before config load
-func BeforeLoad(fn ...func(context.Context, Config) error) options.Option {
+func BeforeLoad(fn ...func(context.Context, Config) error) Option {
-	return func(src interface{}) error {
+	return func(o *Options) {
-		return options.Set(src, fn, ".BeforeLoad")
+		o.BeforeLoad = fn
 	}
 }
 
 // AfterLoad run funcs after config load
-func AfterLoad(fn ...func(context.Context, Config) error) options.Option {
+func AfterLoad(fn ...func(context.Context, Config) error) Option {
-	return func(src interface{}) error {
+	return func(o *Options) {
-		return options.Set(src, fn, ".AfterLoad")
+		o.AfterLoad = fn
 	}
 }
 
 // BeforeSave run funcs before save
-func BeforeSave(fn ...func(context.Context, Config) error) options.Option {
+func BeforeSave(fn ...func(context.Context, Config) error) Option {
-	return func(src interface{}) error {
+	return func(o *Options) {
-		return options.Set(src, fn, ".BeforeSave")
+		o.BeforeSave = fn
 	}
 }
 
 // AfterSave run fncs after save
-func AfterSave(fn ...func(context.Context, Config) error) options.Option {
+func AfterSave(fn ...func(context.Context, Config) error) Option {
-	return func(src interface{}) error {
+	return func(o *Options) {
-		return options.Set(src, fn, ".AfterSave")
+		o.AfterSave = fn
+	}
+}
+
+// Context pass context
+func Context(ctx context.Context) Option {
+	return func(o *Options) {
+		o.Context = ctx
+	}
+}
+
+// Codec sets the source codec
+func Codec(c codec.Codec) Option {
+	return func(o *Options) {
+		o.Codec = c
+	}
+}
+
+// Logger sets the logger
+func Logger(l logger.Logger) Option {
+	return func(o *Options) {
+		o.Logger = l
+	}
+}
+
+// Tracer to be used for tracing
+func Tracer(t tracer.Tracer) Option {
+	return func(o *Options) {
+		o.Tracer = t
 	}
 }
 
 // Struct used as config
-func Struct(v interface{}) options.Option {
+func Struct(v interface{}) Option {
-	return func(src interface{}) error {
+	return func(o *Options) {
-		return options.Set(src, v, ".Struct")
+		o.Struct = v
 	}
 }
 
 // StructTag sets the struct tag that used for filling
-func StructTag(name string) options.Option {
+func StructTag(name string) Option {
-	return func(src interface{}) error {
+	return func(o *Options) {
-		return options.Set(src, name, ".StructTag")
+		o.StructTag = name
+	}
+}
+
+// Name sets the name
+func Name(n string) Option {
+	return func(o *Options) {
+		o.Name = n
 	}
 }
 
@@ -183,8 +249,11 @@ type WatchOptions struct {
 	Coalesce bool
 }
 
+// WatchOption func signature
+type WatchOption func(*WatchOptions)
+
 // NewWatchOptions create WatchOptions struct with provided opts
-func NewWatchOptions(opts ...options.Option) WatchOptions {
+func NewWatchOptions(opts ...WatchOption) WatchOptions {
 	options := WatchOptions{
 		Context:     context.Background(),
 		MinInterval: DefaultWatcherMinInterval,
@@ -196,20 +265,38 @@ func NewWatchOptions(opts ...options.Option) WatchOptions {
 	return options
 }
 
-// Coalesce controls watch event combining
+// WatchContext pass context
-func WatchCoalesce(b bool) options.Option {
+func WatchContext(ctx context.Context) WatchOption {
-	return func(src interface{}) error {
+	return func(o *WatchOptions) {
-		return options.Set(src, b, ".Coalesce")
+		o.Context = ctx
+	}
+}
+
+// WatchCoalesce controls watch event combining
+func WatchCoalesce(b bool) WatchOption {
+	return func(o *WatchOptions) {
+		o.Coalesce = b
 	}
 }
 
 // WatchInterval specifies min and max time.Duration for pulling changes
-func WatchInterval(min, max time.Duration) options.Option {
+func WatchInterval(minTime, maxTime time.Duration) WatchOption {
-	return func(src interface{}) error {
+	return func(o *WatchOptions) {
-		var err error
+		o.MinInterval = minTime
-		if err = options.Set(src, min, ".MinInterval"); err == nil {
+		o.MaxInterval = maxTime
-			err = options.Set(src, max, ".MaxInterval")
+	}
-		}
+}
-		return err
+
+// WatchStruct overrides struct for fill
+func WatchStruct(src interface{}) WatchOption {
+	return func(o *WatchOptions) {
+		o.Struct = src
+	}
+}
+
+// Hooks sets hook runs before action
+func Hooks(h ...options.Hook) Option {
+	return func(o *Options) {
+		o.Hooks = append(o.Hooks, h...)
 	}
 }

database/dsn.go

@@ -0,0 +1,157 @@
+package database
+
+import (
+	"crypto/tls"
+	"errors"
+	"fmt"
+	"net/url"
+	"strings"
+)
+
+var (
+	ErrInvalidDSNAddr      = errors.New("invalid dsn addr")
+	ErrInvalidDSNUnescaped = errors.New("dsn must be escaped")
+	ErrInvalidDSNNoSlash   = errors.New("dsn must contains slash")
+)
+
+type Config struct {
+	TLSConfig *tls.Config
+	Username  string
+	Password  string
+	Scheme    string
+	Host      string
+	Port      string
+	Database  string
+	Params    []string
+}
+
+func (cfg *Config) FormatDSN() string {
+	var s strings.Builder
+
+	if len(cfg.Scheme) > 0 {
+		s.WriteString(cfg.Scheme + "://")
+	}
+	// [username[:password]@]
+	if len(cfg.Username) > 0 {
+		s.WriteString(cfg.Username)
+		if len(cfg.Password) > 0 {
+			s.WriteByte(':')
+			s.WriteString(url.PathEscape(cfg.Password))
+		}
+		s.WriteByte('@')
+	}
+
+	// [host:port]
+	if len(cfg.Host) > 0 {
+		s.WriteString(cfg.Host)
+		if len(cfg.Port) > 0 {
+			s.WriteByte(':')
+			s.WriteString(cfg.Port)
+		}
+	}
+
+	// /dbname
+	s.WriteByte('/')
+	s.WriteString(url.PathEscape(cfg.Database))
+
+	for i := 0; i < len(cfg.Params); i += 2 {
+		if i == 0 {
+			s.WriteString("?")
+		} else {
+			s.WriteString("&")
+		}
+		s.WriteString(cfg.Params[i])
+		s.WriteString("=")
+		s.WriteString(cfg.Params[i+1])
+	}
+
+	return s.String()
+}
+
+func ParseDSN(dsn string) (*Config, error) {
+	cfg := &Config{}
+
+	// [user[:password]@][net[(addr)]]/dbname[?param1=value1&paramN=valueN]
+	// Find last '/' that goes before dbname
+	foundSlash := false
+	for i := len(dsn) - 1; i >= 0; i-- {
+		if dsn[i] == '/' {
+			foundSlash = true
+			var j, k int
+
+			// left part is empty if i <= 0
+			if i > 0 {
+				// Find the first ':' in dsn
+				for j = i; j >= 0; j-- {
+					if dsn[j] == ':' {
+						cfg.Scheme = dsn[0:j]
+					}
+				}
+
+				// [username[:password]@][host]
+				// Find the last '@' in dsn[:i]
+				for j = i; j >= 0; j-- {
+					if dsn[j] == '@' {
+						// username[:password]
+						// Find the second ':' in dsn[:j]
+						for k = 0; k < j; k++ {
+							if dsn[k] == ':' {
+								if cfg.Scheme == dsn[:k] {
+									continue
+								}
+								var err error
+								cfg.Password, err = url.PathUnescape(dsn[k+1 : j])
+								if err != nil {
+									return nil, err
+								}
+								break
+							}
+						}
+						cfg.Username = dsn[len(cfg.Scheme)+3 : k]
+						break
+					}
+				}
+
+				for k = j + 1; k < i; k++ {
+					if dsn[k] == ':' {
+						cfg.Host = dsn[j+1 : k]
+						cfg.Port = dsn[k+1 : i]
+						break
+					}
+				}
+
+			}
+
+			// dbname[?param1=value1&...&paramN=valueN]
+			// Find the first '?' in dsn[i+1:]
+			for j = i + 1; j < len(dsn); j++ {
+				if dsn[j] == '?' {
+					parts := strings.Split(dsn[j+1:], "&")
+					cfg.Params = make([]string, 0, len(parts)*2)
+					for _, p := range parts {
+						k, v, found := strings.Cut(p, "=")
+						if !found {
+							continue
+						}
+						cfg.Params = append(cfg.Params, k, v)
+					}
+
+					break
+				}
+			}
+			var err error
+			dbname := dsn[i+1 : j]
+			if cfg.Database, err = url.PathUnescape(dbname); err != nil {
+				return nil, fmt.Errorf("invalid dbname %q: %w", dbname, err)
+			}
+
+			break
+		}
+	}
+
+	if !foundSlash && len(dsn) > 0 {
+		return nil, ErrInvalidDSNNoSlash
+	}
+
+	return cfg, nil
+}

database/dsn_test.go

@@ -0,0 +1,31 @@
+package database
+
+import (
+	"net/url"
+	"testing"
+)
+
+func TestParseDSN(t *testing.T) {
+	cfg, err := ParseDSN("postgres://username:p@ssword#@host:12345/dbname?key1=val2&key2=val2")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if cfg.Password != "p@ssword#" {
+		t.Fatalf("parsing error")
+	}
+}
+
+func TestFormatDSN(t *testing.T) {
+	src := "postgres://username:p@ssword#@host:12345/dbname?key1=val2&key2=val2"
+	cfg, err := ParseDSN(src)
+	if err != nil {
+		t.Fatal(err)
+	}
+	dst, err := url.PathUnescape(cfg.FormatDSN())
+	if err != nil {
+		t.Fatal(err)
+	}
+	if src != dst {
+		t.Fatalf("\n%s\n%s", src, dst)
+	}
+}

errors/errors.go

@@ -1,14 +1,20 @@
 // Package errors provides a way to return detailed information
 // for an RPC request error. The error is normally JSON encoded.
-package errors // import "go.unistack.org/micro/v4/errors"
+package errors
 
 import (
 	"bytes"
+	"context"
 	"encoding/json"
+	"errors"
 	"fmt"
+	"io"
 	"net/http"
 	"strconv"
 	"strings"
+
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
 )
 
 var (
@@ -38,6 +44,20 @@ var (
 	ErrGatewayTimeout = &Error{Code: 504}
 )
 
+const ProblemContentType = "application/problem+json"
+
+type Problem struct {
+	Type     string `json:"type,omitempty"`
+	Title    string `json:"title,omitempty"`
+	Detail   string `json:"detail,omitempty"`
+	Instance string `json:"instance,omitempty"`
+	Errors   []struct {
+		Title  string `json:"title,omitempty"`
+		Detail string `json:"detail,omitempty"`
+	} `json:"errors,omitempty"`
+	Status int `json:"status,omitempty"`
+}
+
 // Error type
 type Error struct {
 	// ID holds error id or service, usually someting like my_service or id
@@ -256,6 +276,10 @@ func CodeIn(err interface{}, codes ...int32) bool {
 
 // FromError try to convert go error to *Error
 func FromError(err error) *Error {
+	if err == nil {
+		return nil
+	}
+
 	if verr, ok := err.(*Error); ok && verr != nil {
 		return verr
 	}
@@ -340,3 +364,135 @@ func addslashes(str string) string {
 	}
 	return buf.String()
 }
+
+type retryableError struct {
+	err error
+}
+
+// Retryable returns error that can be retried later
+func Retryable(err error) error {
+	return &retryableError{err: err}
+}
+
+type IsRetryableFunc func(error) bool
+
+var (
+	RetrayableOracleErrors = []IsRetryableFunc{
+		func(err error) bool {
+			errmsg := err.Error()
+			switch {
+			case strings.Contains(errmsg, `ORA-`):
+				return true
+			case strings.Contains(errmsg, `can not assign`):
+				return true
+			case strings.Contains(errmsg, `can't assign`):
+				return true
+			}
+			return false
+		},
+	}
+	RetrayablePostgresErrors = []IsRetryableFunc{
+		func(err error) bool {
+			errmsg := err.Error()
+			switch {
+			case strings.Contains(errmsg, `number of field descriptions must equal number of`):
+				return true
+			case strings.Contains(errmsg, `not a pointer`):
+				return true
+			case strings.Contains(errmsg, `values, but dst struct has only`):
+				return true
+			case strings.Contains(errmsg, `struct doesn't have corresponding row field`):
+				return true
+			case strings.Contains(errmsg, `cannot find field`):
+				return true
+			case strings.Contains(errmsg, `cannot scan`) || strings.Contains(errmsg, `cannot convert`):
+				return true
+			case strings.Contains(errmsg, `failed to connect to`):
+				return true
+			}
+			return false
+		},
+	}
+	RetryableMicroErrors = []IsRetryableFunc{
+		func(err error) bool {
+			switch verr := err.(type) {
+			case *Error:
+				switch verr.Code {
+				case 401, 403, 408, 500, 501, 502, 503, 504:
+					return true
+				default:
+					return false
+				}
+			case *retryableError:
+				return true
+			}
+			return false
+		},
+	}
+	RetryableGoErrors = []IsRetryableFunc{
+		func(err error) bool {
+			switch verr := err.(type) {
+			case interface{ SafeToRetry() bool }:
+				return verr.SafeToRetry()
+			case interface{ Timeout() bool }:
+				return verr.Timeout()
+			}
+			switch {
+			case errors.Is(err, io.EOF), errors.Is(err, io.ErrUnexpectedEOF):
+				return true
+			case errors.Is(err, context.DeadlineExceeded):
+				return true
+			case errors.Is(err, io.ErrClosedPipe), errors.Is(err, io.ErrShortBuffer), errors.Is(err, io.ErrShortWrite):
+				return true
+			}
+			return false
+		},
+	}
+	RetryableGrpcErrors = []IsRetryableFunc{
+		func(err error) bool {
+			st, ok := status.FromError(err)
+			if !ok {
+				return false
+			}
+			switch st.Code() {
+			case codes.Unavailable, codes.ResourceExhausted:
+				return true
+			case codes.DeadlineExceeded:
+				return true
+			case codes.Internal:
+				switch {
+				case strings.Contains(st.Message(), `transport: received the unexpected content-type "text/html; charset=UTF-8"`):
+					return true
+				case strings.Contains(st.Message(), io.ErrUnexpectedEOF.Error()):
+					return true
+				case strings.Contains(st.Message(), `stream terminated by RST_STREAM with error code: INTERNAL_ERROR`):
+					return true
+				}
+			}
+			return false
+		},
+	}
+)
+
+// Unwrap provides error wrapping
+func (e *retryableError) Unwrap() error {
+	return e.err
+}
+
+// Error returns the error string
+func (e *retryableError) Error() string {
+	if e.err == nil {
+		return ""
+	}
+	return e.err.Error()
+}
+
+// IsRetryable checks error for ability to retry later
+func IsRetryable(err error, fns ...IsRetryableFunc) bool {
+	for _, fn := range fns {
+		if ok := fn(err); ok {
+			return true
+		}
+	}
+	return false
+}

errors/errors.proto

@@ -1,4 +1,4 @@
-// Copyright 2021-2023 Unistack LLC
+// Copyright 2021 Unistack LLC
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.

errors/errors_test.go

@@ -2,12 +2,19 @@ package errors
 
 import (
 	"encoding/json"
-	er "errors"
+	"errors"
 	"fmt"
 	"net/http"
 	"testing"
 )
 
+func TestIsRetrayable(t *testing.T) {
+	err := fmt.Errorf("ORA-")
+	if !IsRetryable(err, RetrayableOracleErrors...) {
+		t.Fatalf("IsRetrayable not works")
+	}
+}
+
 func TestMarshalJSON(t *testing.T) {
 	e := InternalServerError("id", "err: %v", fmt.Errorf("err: %v", `xxx: "UNIX_TIMESTAMP": invalid identifier`))
 	_, err := json.Marshal(e)
@@ -19,7 +26,7 @@ func TestMarshalJSON(t *testing.T) {
 func TestEmpty(t *testing.T) {
 	msg := "test"
 	var err *Error
-	err = FromError(fmt.Errorf(msg))
+	err = FromError(errors.New(msg))
 	if err.Detail != msg {
 		t.Fatalf("invalid error %v", err)
 	}
@@ -35,7 +42,7 @@ func TestFromError(t *testing.T) {
 	if merr.ID != "go.micro.test" || merr.Code != 404 {
 		t.Fatalf("invalid conversation %v != %v", err, merr)
 	}
-	err = er.New(err.Error())
+	err = errors.New(err.Error())
 	merr = FromError(err)
 	if merr.ID != "go.micro.test" || merr.Code != 404 {
 		t.Fatalf("invalid conversation %v != %v", err, merr)
@@ -50,7 +57,7 @@ func TestEqual(t *testing.T) {
 		t.Fatal("errors must be equal")
 	}
 
-	err3 := er.New("my test err")
+	err3 := errors.New("my test err")
 	if Equal(err1, err3) {
 		t.Fatal("errors must be not equal")
 	}

flow/context.go

@@ -22,3 +22,13 @@ func NewContext(ctx context.Context, f Flow) context.Context {
 	}
 	return context.WithValue(ctx, flowKey{}, f)
 }
+
+// SetOption returns a function to setup a context with given value
+func SetOption(k, v interface{}) Option {
+	return func(o *Options) {
+		if o.Context == nil {
+			o.Context = context.Background()
+		}
+		o.Context = context.WithValue(o.Context, k, v)
+	}
+}

flow/context_test.go

@@ -1,3 +1,5 @@
+//go:build ignore
+
 package flow
 
 import (
@@ -40,3 +42,14 @@ func TestNewContext(t *testing.T) {
 		t.Fatal("NewContext not works")
 	}
 }
+
+func TestSetOption(t *testing.T) {
+	type key struct{}
+	o := SetOption(key{}, "test")
+	opts := &Options{}
+	o(opts)
+
+	if v, ok := opts.Context.Value(key{}).(string); !ok || v == "" {
+		t.Fatal("SetOption not works")
+	}
+}

flow/default.go

@@ -1,17 +1,17 @@
+//go:build ignore
+
 package flow
 
 import (
 	"context"
 	"fmt"
+	"path/filepath"
 	"sync"
 
-	"github.com/silas/dag"
+	"github.com/heimdalr/dag"
 	"go.unistack.org/micro/v4/client"
 	"go.unistack.org/micro/v4/codec"
-	"go.unistack.org/micro/v4/logger"
 	"go.unistack.org/micro/v4/metadata"
-	"go.unistack.org/micro/v4/options"
-	moptions "go.unistack.org/micro/v4/options"
 	"go.unistack.org/micro/v4/store"
 	"go.unistack.org/micro/v4/util/id"
 )
@@ -22,7 +22,7 @@ type microFlow struct {
 
 type microWorkflow struct {
 	opts   Options
-	g      *dag.AcyclicGraph
+	g      *dag.DAG
 	steps  map[string]Step
 	id     string
 	status Status
@@ -34,20 +34,20 @@ func (w *microWorkflow) ID() string {
 	return w.id
 }
 
-func (w *microWorkflow) Steps() ([][]Step, error) {
-	return w.getSteps("", false)
-}
-
 func (w *microWorkflow) Status() Status {
 	return w.status
 }
 
 func (w *microWorkflow) AppendSteps(steps ...Step) error {
+	var err error
 	w.Lock()
+	defer w.Unlock()
 
 	for _, s := range steps {
 		w.steps[s.String()] = s
-		w.g.Add(s)
+		if _, err = w.g.AddVertex(s); err != nil {
+			return err
+		}
 	}
 
 	for _, dst := range steps {
@@ -56,18 +56,13 @@ func (w *microWorkflow) AppendSteps(steps ...Step) error {
 			if !ok {
 				return ErrStepNotExists
 			}
-			w.g.Connect(dag.BasicEdge(src, dst))
+			if err = w.g.AddEdge(src.String(), dst.String()); err != nil {
-		}
-	}
-
-	if err := w.g.Validate(); err != nil {
-		w.Unlock()
 				return err
 			}
+		}
+	}
 
-	w.g.TransitiveReduction()
+	w.g.ReduceTransitively()
-
-	w.Unlock()
 
 	return nil
 }
@@ -76,10 +71,11 @@ func (w *microWorkflow) RemoveSteps(steps ...Step) error {
 	// TODO: handle case when some step requires or required by removed step
 
 	w.Lock()
+	defer w.Unlock()
 
 	for _, s := range steps {
 		delete(w.steps, s.String())
-		w.g.Remove(s)
+		w.g.DeleteVertex(s.String())
 	}
 
 	for _, dst := range steps {
@@ -88,91 +84,34 @@ func (w *microWorkflow) RemoveSteps(steps ...Step) error {
 			if !ok {
 				return ErrStepNotExists
 			}
-			w.g.Connect(dag.BasicEdge(src, dst))
+			w.g.AddEdge(src.String(), dst.String())
 		}
 	}
 
-	if err := w.g.Validate(); err != nil {
+	w.g.ReduceTransitively()
-		w.Unlock()
-		return err
-	}
-
-	w.g.TransitiveReduction()
-
-	w.Unlock()
 
 	return nil
 }
 
-func (w *microWorkflow) getSteps(start string, reverse bool) ([][]Step, error) {
-	var steps [][]Step
-	var root dag.Vertex
-	var err error
-
-	fn := func(n dag.Vertex, idx int) error {
-		if idx == 0 {
-			steps = make([][]Step, 1)
-			steps[0] = make([]Step, 0, 1)
-		} else if idx >= len(steps) {
-			tsteps := make([][]Step, idx+1)
-			copy(tsteps, steps)
-			steps = tsteps
-			steps[idx] = make([]Step, 0, 1)
-		}
-		steps[idx] = append(steps[idx], n.(Step))
-		return nil
-	}
-
-	if start != "" {
-		var ok bool
-		w.RLock()
-		root, ok = w.steps[start]
-		w.RUnlock()
-		if !ok {
-			return nil, ErrStepNotExists
-		}
-	} else {
-		root, err = w.g.Root()
-		if err != nil {
-			return nil, err
-		}
-	}
-
-	if reverse {
-		err = w.g.SortedReverseDepthFirstWalk([]dag.Vertex{root}, fn)
-	} else {
-		err = w.g.SortedDepthFirstWalk([]dag.Vertex{root}, fn)
-	}
-	if err != nil {
-		return nil, err
-	}
-
-	return steps, nil
-}
-
 func (w *microWorkflow) Abort(ctx context.Context, id string) error {
-	workflowStore := store.NewNamespaceStore(w.opts.Store, "workflows"+w.opts.Store.Options().Separator+id)
+	workflowStore := store.NewNamespaceStore(w.opts.Store, filepath.Join("workflows", id))
 	return workflowStore.Write(ctx, "status", &codec.Frame{Data: []byte(StatusAborted.String())})
 }
 
 func (w *microWorkflow) Suspend(ctx context.Context, id string) error {
-	workflowStore := store.NewNamespaceStore(w.opts.Store, "workflows"+w.opts.Store.Options().Separator+id)
+	workflowStore := store.NewNamespaceStore(w.opts.Store, filepath.Join("workflows", id))
 	return workflowStore.Write(ctx, "status", &codec.Frame{Data: []byte(StatusSuspend.String())})
 }
 
 func (w *microWorkflow) Resume(ctx context.Context, id string) error {
-	workflowStore := store.NewNamespaceStore(w.opts.Store, "workflows"+w.opts.Store.Options().Separator+id)
+	workflowStore := store.NewNamespaceStore(w.opts.Store, filepath.Join("workflows", id))
 	return workflowStore.Write(ctx, "status", &codec.Frame{Data: []byte(StatusRunning.String())})
 }
 
-func (w *microWorkflow) Execute(ctx context.Context, req *Message, opts ...options.Option) (string, error) {
+func (w *microWorkflow) Execute(ctx context.Context, req *Message, opts ...ExecuteOption) (string, error) {
 	w.Lock()
 	if !w.init {
-		if err := w.g.Validate(); err != nil {
+		w.g.ReduceTransitively()
-			w.Unlock()
-			return "", err
-		}
-		w.g.TransitiveReduction()
 		w.init = true
 	}
 	w.Unlock()
@@ -182,50 +121,166 @@ func (w *microWorkflow) Execute(ctx context.Context, req *Message, opts ...optio
 		return "", err
 	}
 
-	stepStore := store.NewNamespaceStore(w.opts.Store, "steps"+w.opts.Store.Options().Separator+eid)
+	//	stepStore := store.NewNamespaceStore(w.opts.Store, filepath.Join("steps", eid))
-	workflowStore := store.NewNamespaceStore(w.opts.Store, "workflows"+w.opts.Store.Options().Separator+eid)
+	workflowStore := store.NewNamespaceStore(w.opts.Store, filepath.Join("workflows", eid))
 
 	options := NewExecuteOptions(opts...)
 
-	steps, err := w.getSteps(options.Start, options.Reverse)
+	nopts := make([]ExecuteOption, 0, len(opts)+5)
-	if err != nil {
-		if werr := workflowStore.Write(w.opts.Context, "status", &codec.Frame{Data: []byte(StatusPending.String())}); werr != nil {
-			w.opts.Logger.Errorf(w.opts.Context, "store error: %v", werr)
-		}
-		return "", err
-	}
-
-	var wg sync.WaitGroup
-	cherr := make(chan error, 1)
-	chstatus := make(chan Status, 1)
-
-	nctx, cancel := context.WithCancel(ctx)
-	defer cancel()
-
-	nopts := make([]moptions.Option, 0, len(opts)+5)
 
 	nopts = append(nopts,
-		moptions.Client(w.opts.Client),
+		ExecuteClient(w.opts.Client),
-		moptions.Tracer(w.opts.Tracer),
+		ExecuteTracer(w.opts.Tracer),
-		moptions.Logger(w.opts.Logger),
+		ExecuteLogger(w.opts.Logger),
-		moptions.Meter(w.opts.Meter),
+		ExecuteMeter(w.opts.Meter),
 	)
 	nopts = append(nopts, opts...)
-	done := make(chan struct{})
 
-	if werr := workflowStore.Write(w.opts.Context, "status", &codec.Frame{Data: []byte(StatusRunning.String())}); werr != nil {
+	if werr := workflowStore.Write(ctx, "status", &codec.Frame{Data: []byte(StatusRunning.String())}); werr != nil {
-		w.opts.Logger.Errorf(w.opts.Context, "store error: %v", werr)
+		w.opts.Logger.Error(ctx, "store error: %v", werr)
 		return eid, werr
 	}
-	for idx := range steps {
+
-		for nidx := range steps[idx] {
+	var startID string
-			cstep := steps[idx][nidx]
+	if options.Start == "" {
-			if werr := stepStore.Write(ctx, cstep.ID()+w.opts.Store.Options().Separator+"status", &codec.Frame{Data: []byte(StatusPending.String())}); werr != nil {
+		mp := w.g.GetRoots()
-				return eid, werr
+		if len(mp) != 1 {
+			return eid, ErrStepNotExists
+		}
+		for k := range mp {
+			startID = k
+		}
+	} else {
+		for k, v := range w.g.GetVertices() {
+			if v == options.Start {
+				startID = k
 			}
 		}
 	}
 
+	if startID == "" {
+		return eid, ErrStepNotExists
+	}
+
+	if options.Async {
+		go w.handleWorkflow(startID, nopts...)
+		return eid, nil
+	}
+
+	return eid, w.handleWorkflow(startID, nopts...)
+}
+
+func (w *microWorkflow) handleWorkflow(startID string, opts ...ExecuteOption) error {
+	w.RLock()
+	defer w.RUnlock()
+
+	//	stepStore := store.NewNamespaceStore(w.opts.Store, filepath.Join("steps", eid))
+	// workflowStore := store.NewNamespaceStore(w.opts.Store, filepath.Join("workflows", eid))
+
+	// Get IDs of all descendant vertices.
+	flowIDs, errDes := w.g.GetDescendants(startID)
+	if errDes != nil {
+		return errDes
+	}
+
+	// inputChannels provides for input channels for each of the descendant vertices (+ the start-vertex).
+	inputChannels := make(map[string]chan FlowResult, len(flowIDs)+1)
+
+	// Iterate vertex IDs and create an input channel for each of them and a single
+	// output channel for leaves. Note, this "pre-flight" is needed to ensure we
+	// really have an input channel regardless of how we traverse the tree and spawn
+	// workers.
+	leafCount := 0
+
+	for id := range flowIDs {
+
+		// Get all parents of this vertex.
+		parents, errPar := w.g.GetParents(id)
+		if errPar != nil {
+			return errPar
+		}
+
+		// Create a buffered input channel that has capacity for all parent results.
+		inputChannels[id] = make(chan FlowResult, len(parents))
+
+		if ok, err := w.g.IsLeaf(id); ok && err == nil {
+			leafCount += 1
+		}
+	}
+
+	// outputChannel caries the results of leaf vertices.
+	outputChannel := make(chan FlowResult, leafCount)
+
+	// To also process the start vertex and to have its results being passed to its
+	// children, add it to the vertex IDs. Also add an input channel for the start
+	// vertex and feed the inputs to this channel.
+	flowIDs[startID] = struct{}{}
+	inputChannels[startID] = make(chan FlowResult, len(inputs))
+	for _, i := range inputs {
+		inputChannels[startID] <- i
+	}
+
+	wg := sync.WaitGroup{}
+
+	// Iterate all vertex IDs (now incl. start vertex) and handle each worker (incl.
+	// inputs and outputs) in a separate goroutine.
+	for id := range flowIDs {
+
+		// Get all children of this vertex that later need to be notified. Note, we
+		// collect all children before the goroutine to be able to release the read
+		// lock as early as possible.
+		children, errChildren := w.g.GetChildren(id)
+		if errChildren != nil {
+			return errChildren
+		}
+
+		// Remember to wait for this goroutine.
+		wg.Add(1)
+
+		go func(id string) {
+			// Get this vertex's input channel.
+			// Note, only concurrent read here, which is fine.
+			c := inputChannels[id]
+
+			// Await all parent inputs and stuff them into a slice.
+			parentCount := cap(c)
+			parentResults := make([]FlowResult, parentCount)
+			for i := 0; i < parentCount; i++ {
+				parentResults[i] = <-c
+			}
+
+			// Execute the worker.
+			errWorker := callback(w.g, id, parentResults)
+			if errWorker != nil {
+				return errWorker
+			}
+
+			// Send this worker's FlowResult onto all children's input channels or, if it is
+			// a leaf (i.e. no children), send the result onto the output channel.
+			if len(children) > 0 {
+				for child := range children {
+					inputChannels[child] <- flowResult
+				}
+			} else {
+				outputChannel <- flowResult
+			}
+
+			// "Sign off".
+			wg.Done()
+		}(id)
+	}
+
+	// Wait for all go routines to finish.
+	wg.Wait()
+
+	// Await all leaf vertex results and stuff them into a slice.
+	resultCount := cap(outputChannel)
+	results := make([]FlowResult, resultCount)
+	for i := 0; i < resultCount; i++ {
+		results[i] = <-outputChannel
+	}
+
+	/*
 		go func() {
 			for idx := range steps {
 				for nidx := range steps[idx] {
@@ -247,32 +302,32 @@ func (w *microWorkflow) Execute(ctx context.Context, req *Message, opts ...optio
 						wg.Add(1)
 						go func(step Step) {
 							defer wg.Done()
-						if werr := stepStore.Write(ctx, step.ID()+w.opts.Store.Options().Separator+"req", req); werr != nil {
+							if werr := stepStore.Write(ctx, filepath.Join(step.ID(), "req"), req); werr != nil {
 								cherr <- werr
 								return
 							}
-						if werr := stepStore.Write(ctx, step.ID()+w.opts.Store.Options().Separator+"status", &codec.Frame{Data: []byte(StatusRunning.String())}); werr != nil {
+							if werr := stepStore.Write(ctx, filepath.Join(step.ID(), "status"), &codec.Frame{Data: []byte(StatusRunning.String())}); werr != nil {
 								cherr <- werr
 								return
 							}
 							rsp, serr := step.Execute(nctx, req, nopts...)
 							if serr != nil {
 								step.SetStatus(StatusFailure)
-							if werr := stepStore.Write(ctx, step.ID()+w.opts.Store.Options().Separator+"rsp", serr); werr != nil && w.opts.Logger.V(logger.ErrorLevel) {
+								if werr := stepStore.Write(ctx, filepath.Join(step.ID(), "rsp"), serr); werr != nil && w.opts.Logger.V(logger.ErrorLevel) {
 									w.opts.Logger.Errorf(ctx, "store write error: %v", werr)
 								}
-							if werr := stepStore.Write(ctx, step.ID()+w.opts.Store.Options().Separator+"status", &codec.Frame{Data: []byte(StatusFailure.String())}); werr != nil && w.opts.Logger.V(logger.ErrorLevel) {
+								if werr := stepStore.Write(ctx, filepath.Join(step.ID(), "status"), &codec.Frame{Data: []byte(StatusFailure.String())}); werr != nil && w.opts.Logger.V(logger.ErrorLevel) {
 									w.opts.Logger.Errorf(ctx, "store write error: %v", werr)
 								}
 								cherr <- serr
 								return
 							}
-						if werr := stepStore.Write(ctx, step.ID()+w.opts.Store.Options().Separator+"rsp", rsp); werr != nil {
+							if werr := stepStore.Write(ctx, filepath.Join(step.ID(), "rsp"), rsp); werr != nil {
 								w.opts.Logger.Errorf(ctx, "store write error: %v", werr)
 								cherr <- werr
 								return
 							}
-						if werr := stepStore.Write(ctx, step.ID()+w.opts.Store.Options().Separator+"status", &codec.Frame{Data: []byte(StatusSuccess.String())}); werr != nil {
+							if werr := stepStore.Write(ctx, filepath.Join(step.ID(), "status"), &codec.Frame{Data: []byte(StatusSuccess.String())}); werr != nil {
 								w.opts.Logger.Errorf(ctx, "store write error: %v", werr)
 								cherr <- werr
 								return
@@ -280,32 +335,32 @@ func (w *microWorkflow) Execute(ctx context.Context, req *Message, opts ...optio
 						}(cstep)
 						wg.Wait()
 					} else {
-					if werr := stepStore.Write(ctx, cstep.ID()+w.opts.Store.Options().Separator+"req", req); werr != nil {
+						if werr := stepStore.Write(ctx, filepath.Join(cstep.ID(), "req"), req); werr != nil {
 							cherr <- werr
 							return
 						}
-					if werr := stepStore.Write(ctx, cstep.ID()+w.opts.Store.Options().Separator+"status", &codec.Frame{Data: []byte(StatusRunning.String())}); werr != nil {
+						if werr := stepStore.Write(ctx, filepath.Join(cstep.ID(), "status"), &codec.Frame{Data: []byte(StatusRunning.String())}); werr != nil {
 							cherr <- werr
 							return
 						}
 						rsp, serr := cstep.Execute(nctx, req, nopts...)
 						if serr != nil {
 							cstep.SetStatus(StatusFailure)
-						if werr := stepStore.Write(ctx, cstep.ID()+w.opts.Store.Options().Separator+"rsp", serr); werr != nil && w.opts.Logger.V(logger.ErrorLevel) {
+							if werr := stepStore.Write(ctx, filepath.Join(cstep.ID(), "rsp"), serr); werr != nil && w.opts.Logger.V(logger.ErrorLevel) {
 								w.opts.Logger.Errorf(ctx, "store write error: %v", werr)
 							}
-						if werr := stepStore.Write(ctx, cstep.ID()+w.opts.Store.Options().Separator+"status", &codec.Frame{Data: []byte(StatusFailure.String())}); werr != nil && w.opts.Logger.V(logger.ErrorLevel) {
+							if werr := stepStore.Write(ctx, filepath.Join(cstep.ID(), "status"), &codec.Frame{Data: []byte(StatusFailure.String())}); werr != nil && w.opts.Logger.V(logger.ErrorLevel) {
 								w.opts.Logger.Errorf(ctx, "store write error: %v", werr)
 							}
 							cherr <- serr
 							return
 						}
-					if werr := stepStore.Write(ctx, cstep.ID()+w.opts.Store.Options().Separator+"rsp", rsp); werr != nil {
+						if werr := stepStore.Write(ctx, filepath.Join(cstep.ID(), "rsp"), rsp); werr != nil {
 							w.opts.Logger.Errorf(ctx, "store write error: %v", werr)
 							cherr <- werr
 							return
 						}
-					if werr := stepStore.Write(ctx, cstep.ID()+w.opts.Store.Options().Separator+"status", &codec.Frame{Data: []byte(StatusSuccess.String())}); werr != nil {
+						if werr := stepStore.Write(ctx, filepath.Join(cstep.ID(), "status"), &codec.Frame{Data: []byte(StatusSuccess.String())}); werr != nil {
 							cherr <- werr
 							return
 						}
@@ -346,12 +401,12 @@ func (w *microWorkflow) Execute(ctx context.Context, req *Message, opts ...optio
 				w.opts.Logger.Errorf(w.opts.Context, "store error: %v", werr)
 			}
 		}
-
+	*/
-	return eid, err
+	return err
 }
 
 // NewFlow create new flow
-func NewFlow(opts ...options.Option) Flow {
+func NewFlow(opts ...Option) Flow {
 	options := NewOptions(opts...)
 	return &microFlow{opts: options}
 }
@@ -360,7 +415,7 @@ func (f *microFlow) Options() Options {
 	return f.opts
 }
 
-func (f *microFlow) Init(opts ...options.Option) error {
+func (f *microFlow) Init(opts ...Option) error {
 	for _, o := range opts {
 		o(&f.opts)
 	}
@@ -387,11 +442,11 @@ func (f *microFlow) WorkflowList(ctx context.Context) ([]Workflow, error) {
 }
 
 func (f *microFlow) WorkflowCreate(ctx context.Context, id string, steps ...Step) (Workflow, error) {
-	w := &microWorkflow{opts: f.opts, id: id, g: &dag.AcyclicGraph{}, steps: make(map[string]Step, len(steps))}
+	w := &microWorkflow{opts: f.opts, id: id, g: &dag.DAG{}, steps: make(map[string]Step, len(steps))}
 
 	for _, s := range steps {
 		w.steps[s.String()] = s
-		w.g.Add(s)
+		w.g.AddVertex(s)
 	}
 
 	for _, dst := range steps {
@@ -400,14 +455,11 @@ func (f *microFlow) WorkflowCreate(ctx context.Context, id string, steps ...Step
 			if !ok {
 				return nil, ErrStepNotExists
 			}
-			w.g.Connect(dag.BasicEdge(src, dst))
+			w.g.AddEdge(src.String(), dst.String())
 		}
 	}
 
-	if err := w.g.Validate(); err != nil {
+	w.g.ReduceTransitively()
-		return nil, err
-	}
-	w.g.TransitiveReduction()
 
 	w.init = true
 
@@ -489,17 +541,17 @@ func (s *microCallStep) SetStatus(status Status) {
 	s.status = status
 }
 
-func (s *microCallStep) Execute(ctx context.Context, req *Message, opts ...options.Option) (*Message, error) {
+func (s *microCallStep) Execute(ctx context.Context, req *Message, opts ...ExecuteOption) (*Message, error) {
 	options := NewExecuteOptions(opts...)
 	if options.Client == nil {
 		return nil, ErrMissingClient
 	}
 	rsp := &codec.Frame{}
-	copts := []moptions.Option{client.Retries(0)}
+	copts := []client.CallOption{client.WithRetries(0)}
 	if options.Timeout > 0 {
 		copts = append(copts,
-			client.RequestTimeout(options.Timeout),
+			client.WithRequestTimeout(options.Timeout),
-			client.DialTimeout(options.Timeout))
+			client.WithDialTimeout(options.Timeout))
 	}
 	nctx := metadata.NewOutgoingContext(ctx, req.Header)
 	err := options.Client.Call(nctx, options.Client.NewRequest(s.service, s.method, &codec.Frame{Data: req.Body}), rsp, copts...)
@@ -572,18 +624,18 @@ func (s *microPublishStep) SetStatus(status Status) {
 	s.status = status
 }
 
-func (s *microPublishStep) Execute(ctx context.Context, req *Message, opts ...options.Option) (*Message, error) {
+func (s *microPublishStep) Execute(ctx context.Context, req *Message, opts ...ExecuteOption) (*Message, error) {
 	return nil, nil
 }
 
 // NewCallStep create new step with client.Call
-func NewCallStep(service string, name string, method string, opts ...options.Option) Step {
+func NewCallStep(service string, name string, method string, opts ...StepOption) Step {
 	options := NewStepOptions(opts...)
 	return &microCallStep{service: service, method: name + "." + method, opts: options}
 }
 
 // NewPublishStep create new step with client.Publish
-func NewPublishStep(topic string, opts ...options.Option) Step {
+func NewPublishStep(topic string, opts ...StepOption) Step {
 	options := NewStepOptions(opts...)
 	return &microPublishStep{topic: topic, opts: options}
 }

flow/flow.go

@@ -8,7 +8,6 @@ import (
 	"sync/atomic"
 
 	"go.unistack.org/micro/v4/metadata"
-	"go.unistack.org/micro/v4/options"
 )
 
 var (
@@ -52,7 +51,7 @@ type Step interface {
 	// Endpoint returns rpc endpoint service_name.service_method or broker topic
 	Endpoint() string
 	// Execute step run
-	Execute(ctx context.Context, req *Message, opts ...options.Option) (*Message, error)
+	Execute(ctx context.Context, req *Message, opts ...ExecuteOption) (*Message, error)
 	// Requires returns dependent steps
 	Requires() []string
 	// Options returns step options
@@ -119,15 +118,13 @@ type Workflow interface {
 	// ID returns id of the workflow
 	ID() string
 	// Execute workflow with args, return execution id and error
-	Execute(ctx context.Context, req *Message, opts ...options.Option) (string, error)
+	Execute(ctx context.Context, req *Message, opts ...ExecuteOption) (string, error)
 	// RemoveSteps remove steps from workflow
 	RemoveSteps(steps ...Step) error
 	// AppendSteps append steps to workflow
 	AppendSteps(steps ...Step) error
 	// Status returns workflow status
 	Status() Status
-	// Steps returns steps slice where parallel steps returned on the same level
-	Steps() ([][]Step, error)
 	// Suspend suspends execution
 	Suspend(ctx context.Context, id string) error
 	// Resume resumes execution
@@ -141,7 +138,7 @@ type Flow interface {
 	// Options returns options
 	Options() Options
 	// Init initialize
-	Init(...options.Option) error
+	Init(...Option) error
 	// WorkflowCreate creates new workflow with specific id and steps
 	WorkflowCreate(ctx context.Context, id string, steps ...Step) (Workflow, error)
 	// WorkflowSave saves workflow

flow/options.go

@@ -7,11 +7,13 @@ import (
 	"go.unistack.org/micro/v4/client"
 	"go.unistack.org/micro/v4/logger"
 	"go.unistack.org/micro/v4/meter"
-	"go.unistack.org/micro/v4/options"
 	"go.unistack.org/micro/v4/store"
 	"go.unistack.org/micro/v4/tracer"
 )
 
+// Option func
+type Option func(*Options)
+
 // Options server struct
 type Options struct {
 	// Context holds the external options and can be used for flow shutdown
@@ -29,7 +31,7 @@ type Options struct {
 }
 
 // NewOptions returns new options struct with default or passed values
-func NewOptions(opts ...options.Option) Options {
+func NewOptions(opts ...Option) Options {
 	options := Options{
 		Context: context.Background(),
 		Logger:  logger.DefaultLogger,
@@ -45,12 +47,66 @@ func NewOptions(opts ...options.Option) Options {
 	return options
 }
 
+// Logger sets the logger option
+func Logger(l logger.Logger) Option {
+	return func(o *Options) {
+		o.Logger = l
+	}
+}
+
+// Meter sets the meter option
+func Meter(m meter.Meter) Option {
+	return func(o *Options) {
+		o.Meter = m
+	}
+}
+
+// Client to use for sync/async communication
+func Client(c client.Client) Option {
+	return func(o *Options) {
+		o.Client = c
+	}
+}
+
+// Context specifies a context for the service.
+// Can be used to signal shutdown of the flow
+// or can be used for extra option values.
+func Context(ctx context.Context) Option {
+	return func(o *Options) {
+		o.Context = ctx
+	}
+}
+
+// Tracer mechanism for distributed tracking
+func Tracer(t tracer.Tracer) Option {
+	return func(o *Options) {
+		o.Tracer = t
+	}
+}
+
+// Store used for intermediate results
+func Store(s store.Store) Option {
+	return func(o *Options) {
+		o.Store = s
+	}
+}
+
+// WorkflowOption func signature
+type WorkflowOption func(*WorkflowOptions)
+
 // WorkflowOptions holds workflow options
 type WorkflowOptions struct {
 	Context context.Context
 	ID      string
 }
 
+// WorkflowID set workflow id
+func WorkflowID(id string) WorkflowOption {
+	return func(o *WorkflowOptions) {
+		o.ID = id
+	}
+}
+
 // ExecuteOptions holds execute options
 type ExecuteOptions struct {
 	// Client holds the client.Client
@@ -67,28 +123,64 @@ type ExecuteOptions struct {
 	Start string
 	// Timeout for execution
 	Timeout time.Duration
-	// Reverse execution
-	Reverse bool
 	// Async enables async execution
 	Async bool
 }
 
-// Reverse says that dag must be run in reverse order
+// ExecuteOption func signature
-func Reverse(b bool) options.Option {
+type ExecuteOption func(*ExecuteOptions)
-	return func(src interface{}) error {
+
-		return options.Set(src, b, ".Reverse")
+// ExecuteClient pass client.Client to ExecuteOption
+func ExecuteClient(c client.Client) ExecuteOption {
+	return func(o *ExecuteOptions) {
+		o.Client = c
 	}
 }
 
-// Async says that caller does not wait for execution complete
+// ExecuteTracer pass tracer.Tracer to ExecuteOption
-func Async(b bool) options.Option {
+func ExecuteTracer(t tracer.Tracer) ExecuteOption {
-	return func(src interface{}) error {
+	return func(o *ExecuteOptions) {
-		return options.Set(src, b, ".Async")
+		o.Tracer = t
+	}
+}
+
+// ExecuteLogger pass logger.Logger to ExecuteOption
+func ExecuteLogger(l logger.Logger) ExecuteOption {
+	return func(o *ExecuteOptions) {
+		o.Logger = l
+	}
+}
+
+// ExecuteMeter pass meter.Meter to ExecuteOption
+func ExecuteMeter(m meter.Meter) ExecuteOption {
+	return func(o *ExecuteOptions) {
+		o.Meter = m
+	}
+}
+
+// ExecuteContext pass context.Context ot ExecuteOption
+func ExecuteContext(ctx context.Context) ExecuteOption {
+	return func(o *ExecuteOptions) {
+		o.Context = ctx
+	}
+}
+
+// ExecuteTimeout pass timeout time.Duration for execution
+func ExecuteTimeout(td time.Duration) ExecuteOption {
+	return func(o *ExecuteOptions) {
+		o.Timeout = td
+	}
+}
+
+// ExecuteAsync says that caller does not wait for execution complete
+func ExecuteAsync(b bool) ExecuteOption {
+	return func(o *ExecuteOptions) {
+		o.Async = b
 	}
 }
 
 // NewExecuteOptions create new ExecuteOptions struct
-func NewExecuteOptions(opts ...options.Option) ExecuteOptions {
+func NewExecuteOptions(opts ...ExecuteOption) ExecuteOptions {
 	options := ExecuteOptions{
 		Client:  client.DefaultClient,
 		Logger:  logger.DefaultLogger,
@@ -110,8 +202,11 @@ type StepOptions struct {
 	Requires []string
 }
 
+// StepOption func signature
+type StepOption func(*StepOptions)
+
 // NewStepOptions create new StepOptions struct
-func NewStepOptions(opts ...options.Option) StepOptions {
+func NewStepOptions(opts ...StepOption) StepOptions {
 	options := StepOptions{
 		Context: context.Background(),
 	}
@@ -121,23 +216,23 @@ func NewStepOptions(opts ...options.Option) StepOptions {
 	return options
 }
 
-// Requires specifies required steps
+// StepID sets the step id for dag
-func Requires(steps ...string) options.Option {
+func StepID(id string) StepOption {
-	return func(src interface{}) error {
+	return func(o *StepOptions) {
-		return options.Set(src, steps, ".Requires")
+		o.ID = id
 	}
 }
 
-// Fallback set the step to run on error
+// StepRequires specifies required steps
-func Fallback(step string) options.Option {
+func StepRequires(steps ...string) StepOption {
-	return func(src interface{}) error {
+	return func(o *StepOptions) {
-		return options.Set(src, step, ".Fallback")
+		o.Requires = steps
 	}
 }
 
-// ID sets the step ID
+// StepFallback set the step to run on error
-func StepID(id string) options.Option {
+func StepFallback(step string) StepOption {
-	return func(src interface{}) error {
+	return func(o *StepOptions) {
-		return options.Set(src, id, ".ID")
+		o.Fallback = step
 	}
 }

fsm/default.go

@@ -32,7 +32,7 @@ type fsm struct {
 
 // NewFSM creates a new finite state machine having the specified initial state
 // with specified options
-func NewFSM(opts ...Option) *fsm {
+func NewFSM(opts ...Option) FSM {
 	return &fsm{
 		statesMap: map[string]StateFunc{},
 		opts:      NewOptions(opts...),

fsm/fsm.go

@@ -1,4 +1,4 @@
-package fsm // import "go.unistack.org/micro/v4/fsm"
+package fsm
 
 import (
 	"context"

fsm/fsm_test.go

@@ -17,7 +17,7 @@ func TestFSMStart(t *testing.T) {
 
 	wrapper := func(next StateFunc) StateFunc {
 		return func(sctx context.Context, s State, opts ...StateOption) (State, error) {
-			sctx = logger.NewContext(sctx, logger.Fields("state", s.Name()))
+			sctx = logger.NewContext(sctx, logger.DefaultLogger.Fields("state", s.Name()))
 			return next(sctx, s, opts...)
 		}
 	}

go.mod

@@ -1,20 +1,34 @@
 module go.unistack.org/micro/v4
 
-go 1.20
+go 1.22.0
 
 require (
-	github.com/DATA-DOG/go-sqlmock v1.5.0
+	dario.cat/mergo v1.0.1
-	github.com/google/uuid v1.3.0
+	github.com/DATA-DOG/go-sqlmock v1.5.2
-	github.com/imdario/mergo v0.3.15
+	github.com/KimMachineGun/automemlimit v0.7.0
+	github.com/ash3in/uuidv8 v1.2.0
+	github.com/google/uuid v1.6.0
+	github.com/matoous/go-nanoid v1.5.1
 	github.com/patrickmn/go-cache v2.1.0+incompatible
 	github.com/silas/dag v0.0.0-20220518035006-a7e85ada93c5
-	golang.org/x/sync v0.1.0
+	github.com/spf13/cast v1.7.1
-	golang.org/x/sys v0.7.0
+	go.uber.org/atomic v1.11.0
-	google.golang.org/grpc v1.54.0
+	go.uber.org/automaxprocs v1.6.0
-	google.golang.org/protobuf v1.30.0
+	go.unistack.org/micro-proto/v4 v4.1.0
+	golang.org/x/sync v0.10.0
+	google.golang.org/grpc v1.69.4
+	google.golang.org/protobuf v1.36.3
+	gopkg.in/yaml.v3 v3.0.1
 )
 
 require (
-	github.com/golang/protobuf v1.5.3 // indirect
+	github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc // indirect
-	google.golang.org/genproto v0.0.0-20230410155749-daa745c078e1 // indirect
+	github.com/pbnjay/memory v0.0.0-20210728143218-7b4eea64cf58 // indirect
+	github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2 // indirect
+	github.com/rogpeppe/go-internal v1.13.1 // indirect
+	github.com/stretchr/testify v1.10.0 // indirect
+	golang.org/x/net v0.34.0 // indirect
+	golang.org/x/sys v0.29.0 // indirect
+	google.golang.org/genproto/googleapis/rpc v0.0.0-20241216192217-9240e9c98484 // indirect
+	gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c // indirect
 )

go.sum

@@ -1,33 +1,69 @@
-github.com/DATA-DOG/go-sqlmock v1.5.0 h1:Shsta01QNfFxHCfpW6YH2STWB0MudeXXEWMr20OEh60=
+dario.cat/mergo v1.0.1 h1:Ra4+bf83h2ztPIQYNP99R6m+Y7KfnARDfID+a+vLl4s=
-github.com/DATA-DOG/go-sqlmock v1.5.0/go.mod h1:f/Ixk793poVmq4qj/V1dPUg2JEAKC73Q5eFN3EC/SaM=
+dario.cat/mergo v1.0.1/go.mod h1:uNxQE+84aUszobStD9th8a29P2fMDhsBdgRYvZOxGmk=
-github.com/golang/protobuf v1.5.0/go.mod h1:FsONVRAS9T7sI+LIUmWTfcYkHO4aIWwzhcaSAoJOfIk=
+github.com/DATA-DOG/go-sqlmock v1.5.2 h1:OcvFkGmslmlZibjAjaHm3L//6LiuBgolP7OputlJIzU=
-github.com/golang/protobuf v1.5.3 h1:KhyjKVUg7Usr/dYsdSqoFveMYd5ko72D+zANwlG1mmg=
+github.com/DATA-DOG/go-sqlmock v1.5.2/go.mod h1:88MAG/4G7SMwSE3CeA0ZKzrT5CiOU3OJ+JlNzwDqpNU=
-github.com/golang/protobuf v1.5.3/go.mod h1:XVQd3VNwM+JqD3oG2Ue2ip4fOMUkwXdXDdiuN0vRsmY=
+github.com/KimMachineGun/automemlimit v0.7.0 h1:7G06p/dMSf7G8E6oq+f2uOPuVncFyIlDI/pBWK49u88=
-github.com/google/go-cmp v0.5.5/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
+github.com/KimMachineGun/automemlimit v0.7.0/go.mod h1:QZxpHaGOQoYvFhv/r4u3U0JTC2ZcOwbSr11UZF46UBM=
-github.com/google/go-cmp v0.5.9 h1:O2Tfq5qg4qc4AmwVlvv0oLiVAGB7enBSJ2x2DqQFi38=
+github.com/ash3in/uuidv8 v1.2.0 h1:2oogGdtCPwaVtyvPPGin4TfZLtOGE5F+W++E880G6SI=
-github.com/google/uuid v1.3.0 h1:t6JiXgmwXMjEs8VusXIJk2BXHsn+wx8BZdTaoZ5fu7I=
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 github.com/silas/dag v0.0.0-20220518035006-a7e85ada93c5 h1:G/FZtUu7a6NTWl3KUHMV9jkLAh/Rvtf03NWMHaEDl+E=
 github.com/silas/dag v0.0.0-20220518035006-a7e85ada93c5/go.mod h1:7RTUFBdIRC9nZ7/3RyRNH1bdqIShrDejd1YbLwgPS+I=
-golang.org/x/net v0.8.0 h1:Zrh2ngAOFYneWTAIAPethzeaQLuHwhuBkuV6ZiRnUaQ=
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-golang.org/x/sync v0.1.0 h1:wsuoTGHzEhffawBOhz5CYhcrV4IdKZbEyZjBMuTp12o=
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-golang.org/x/sync v0.1.0/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
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-golang.org/x/sys v0.7.0 h1:3jlCCIQZPdOYu1h8BkNvLz8Kgwtae2cagcG/VamtZRU=
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-golang.org/x/sys v0.7.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+go.uber.org/atomic v1.11.0 h1:ZvwS0R+56ePWxUNi+Atn9dWONBPp/AUETXlHW0DxSjE=
-golang.org/x/text v0.8.0 h1:57P1ETyNKtuIjB4SRd15iJxuhj8Gc416Y78H3qgMh68=
+go.uber.org/atomic v1.11.0/go.mod h1:LUxbIzbOniOlMKjJjyPfpl4v+PKK2cNJn91OQbhoJI0=
-golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
+go.uber.org/automaxprocs v1.6.0 h1:O3y2/QNTOdbF+e/dpXNNW7Rx2hZ4sTIPyybbxyNqTUs=
-google.golang.org/genproto v0.0.0-20230410155749-daa745c078e1 h1:KpwkzHKEF7B9Zxg18WzOa7djJ+Ha5DzthMyZYQfEn2A=
+go.uber.org/automaxprocs v1.6.0/go.mod h1:ifeIMSnPZuznNm6jmdzmU3/bfk01Fe2fotchwEFJ8r8=
-google.golang.org/genproto v0.0.0-20230410155749-daa745c078e1/go.mod h1:nKE/iIaLqn2bQwXBg8f1g2Ylh6r5MN5CmZvuzZCgsCU=
+go.unistack.org/micro-proto/v4 v4.1.0 h1:qPwL2n/oqh9RE3RTTDgt28XK3QzV597VugQPaw9lKUk=
-google.golang.org/grpc v1.54.0 h1:EhTqbhiYeixwWQtAEZAxmV9MGqcjEU2mFx52xCzNyag=
+go.unistack.org/micro-proto/v4 v4.1.0/go.mod h1:ArmK7o+uFvxSY3dbJhKBBX4Pm1rhWdLEFf3LxBrMtec=
-google.golang.org/grpc v1.54.0/go.mod h1:PUSEXI6iWghWaB6lXM4knEgpJNu2qUcKfDtNci3EC2g=
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-google.golang.org/protobuf v1.26.0-rc.1/go.mod h1:jlhhOSvTdKEhbULTjvd4ARK9grFBp09yW+WbY/TyQbw=
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-google.golang.org/protobuf v1.26.0/go.mod h1:9q0QmTI4eRPtz6boOQmLYwt+qCgq0jsYwAQnmE0givc=
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-google.golang.org/protobuf v1.30.0/go.mod h1:HV8QOd/L58Z+nl8r43ehVNZIU/HEI6OcFqwMG9pJV4I=
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+google.golang.org/grpc v1.69.4/go.mod h1:vyjdE6jLBI76dgpDojsFGNaHlxdjXN9ghpnd2o7JGZ4=
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+google.golang.org/protobuf v1.36.3/go.mod h1:9fA7Ob0pmnwhb644+1+CVWFRbNajQ6iRojtC/QF5bRE=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c h1:Hei/4ADfdWqJk1ZMxUNpqntNwaWcugrBjAiHlqqRiVk=
+gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c/go.mod h1:JHkPIbrfpd72SG/EVd6muEfDQjcINNoR0C8j2r3qZ4Q=
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
 gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

hooks/metadata/metadata.go

@@ -0,0 +1,117 @@
+package metadata
+
+import (
+	"context"
+
+	"go.unistack.org/micro/v4/client"
+	"go.unistack.org/micro/v4/metadata"
+	"go.unistack.org/micro/v4/server"
+)
+
+type wrapper struct {
+	keys []string
+
+	client.Client
+}
+
+func NewClientWrapper(keys ...string) client.Wrapper {
+	return func(c client.Client) client.Client {
+		handler := &wrapper{
+			Client: c,
+			keys:   keys,
+		}
+		return handler
+	}
+}
+
+func NewClientCallWrapper(keys ...string) client.CallWrapper {
+	return func(fn client.CallFunc) client.CallFunc {
+		return func(ctx context.Context, addr string, req client.Request, rsp interface{}, opts client.CallOptions) error {
+			if keys == nil {
+				return fn(ctx, addr, req, rsp, opts)
+			}
+			if imd, iok := metadata.FromIncomingContext(ctx); iok && imd != nil {
+				omd, ook := metadata.FromOutgoingContext(ctx)
+				if !ook || omd == nil {
+					omd = metadata.New(len(imd))
+				}
+				for _, k := range keys {
+					if v, ok := imd.Get(k); ok {
+						omd.Add(k, v...)
+					}
+				}
+				if !ook {
+					ctx = metadata.NewOutgoingContext(ctx, omd)
+				}
+			}
+			return fn(ctx, addr, req, rsp, opts)
+		}
+	}
+}
+
+func (w *wrapper) Call(ctx context.Context, req client.Request, rsp interface{}, opts ...client.CallOption) error {
+	if w.keys == nil {
+		return w.Client.Call(ctx, req, rsp, opts...)
+	}
+	if imd, iok := metadata.FromIncomingContext(ctx); iok && imd != nil {
+		omd, ook := metadata.FromOutgoingContext(ctx)
+		if !ook || omd == nil {
+			omd = metadata.New(len(imd))
+		}
+		for _, k := range w.keys {
+			if v, ok := imd.Get(k); ok {
+				omd.Add(k, v...)
+			}
+		}
+		if !ook {
+			ctx = metadata.NewOutgoingContext(ctx, omd)
+		}
+	}
+	return w.Client.Call(ctx, req, rsp, opts...)
+}
+
+func (w *wrapper) Stream(ctx context.Context, req client.Request, opts ...client.CallOption) (client.Stream, error) {
+	if w.keys == nil {
+		return w.Client.Stream(ctx, req, opts...)
+	}
+	if imd, iok := metadata.FromIncomingContext(ctx); iok && imd != nil {
+		omd, ook := metadata.FromOutgoingContext(ctx)
+		if !ook || omd == nil {
+			omd = metadata.New(len(imd))
+		}
+		for _, k := range w.keys {
+			if v, ok := imd.Get(k); ok {
+				omd.Add(k, v...)
+			}
+		}
+		if !ook {
+			ctx = metadata.NewOutgoingContext(ctx, omd)
+		}
+	}
+	return w.Client.Stream(ctx, req, opts...)
+}
+
+func NewServerHandlerWrapper(keys ...string) server.HandlerWrapper {
+	return func(fn server.HandlerFunc) server.HandlerFunc {
+		return func(ctx context.Context, req server.Request, rsp interface{}) error {
+			if keys == nil {
+				return fn(ctx, req, rsp)
+			}
+			if imd, iok := metadata.FromIncomingContext(ctx); iok && imd != nil {
+				omd, ook := metadata.FromOutgoingContext(ctx)
+				if !ook || omd == nil {
+					omd = metadata.New(len(imd))
+				}
+				for _, k := range keys {
+					if v, ok := imd.Get(k); ok {
+						omd.Add(k, v...)
+					}
+				}
+				if !ook {
+					ctx = metadata.NewOutgoingContext(ctx, omd)
+				}
+			}
+			return fn(ctx, req, rsp)
+		}
+	}
+}

hooks/recovery/recovery.go

@@ -0,0 +1,63 @@
+package recovery
+
+import (
+	"context"
+	"fmt"
+
+	"go.unistack.org/micro/v4/errors"
+	"go.unistack.org/micro/v4/server"
+)
+
+func NewOptions(opts ...Option) Options {
+	options := Options{
+		ServerHandlerFn: DefaultServerHandlerFn,
+	}
+	for _, o := range opts {
+		o(&options)
+	}
+	return options
+}
+
+type Options struct {
+	ServerHandlerFn func(context.Context, server.Request, interface{}, error) error
+}
+
+type Option func(*Options)
+
+func ServerHandlerFunc(fn func(context.Context, server.Request, interface{}, error) error) Option {
+	return func(o *Options) {
+		o.ServerHandlerFn = fn
+	}
+}
+
+var DefaultServerHandlerFn = func(ctx context.Context, req server.Request, rsp interface{}, err error) error {
+	return errors.BadRequest("", "%v", err)
+}
+
+var Hook = NewHook()
+
+type hook struct {
+	opts Options
+}
+
+func NewHook(opts ...Option) *hook {
+	return &hook{opts: NewOptions(opts...)}
+}
+
+func (w *hook) ServerHandler(next server.FuncHandler) server.FuncHandler {
+	return func(ctx context.Context, req server.Request, rsp interface{}) (err error) {
+		defer func() {
+			r := recover()
+			switch verr := r.(type) {
+			case nil:
+				return
+			case error:
+				err = w.opts.ServerHandlerFn(ctx, req, rsp, verr)
+			default:
+				err = w.opts.ServerHandlerFn(ctx, req, rsp, fmt.Errorf("%v", r))
+			}
+		}()
+		err = next(ctx, req, rsp)
+		return err
+	}
+}

hooks/requestid/requestid.go

@@ -0,0 +1,114 @@
+package requestid
+
+import (
+	"context"
+	"net/textproto"
+
+	"go.unistack.org/micro/v4/client"
+	"go.unistack.org/micro/v4/metadata"
+	"go.unistack.org/micro/v4/server"
+	"go.unistack.org/micro/v4/util/id"
+)
+
+type XRequestIDKey struct{}
+
+// DefaultMetadataKey contains metadata key
+var DefaultMetadataKey = textproto.CanonicalMIMEHeaderKey("x-request-id")
+
+// DefaultMetadataFunc wil be used if user not provide own func to fill metadata
+var DefaultMetadataFunc = func(ctx context.Context) (context.Context, error) {
+	var xid string
+
+	cid, cok := ctx.Value(XRequestIDKey{}).(string)
+	if cok && cid != "" {
+		xid = cid
+	}
+
+	imd, iok := metadata.FromIncomingContext(ctx)
+	if !iok || imd == nil {
+		imd = metadata.New(1)
+		ctx = metadata.NewIncomingContext(ctx, imd)
+	}
+
+	omd, ook := metadata.FromOutgoingContext(ctx)
+	if !ook || omd == nil {
+		omd = metadata.New(1)
+		ctx = metadata.NewOutgoingContext(ctx, omd)
+	}
+
+	if xid == "" {
+		var ids []string
+		if ids, iok = imd.Get(DefaultMetadataKey); iok {
+			for i := range ids {
+				if ids[i] != "" {
+					xid = ids[i]
+				}
+			}
+		}
+		if ids, ook = omd.Get(DefaultMetadataKey); ook {
+			for i := range ids {
+				if ids[i] != "" {
+					xid = ids[i]
+				}
+			}
+		}
+	}
+
+	if xid == "" {
+		var err error
+		xid, err = id.New()
+		if err != nil {
+			return ctx, err
+		}
+	}
+
+	if !cok {
+		ctx = context.WithValue(ctx, XRequestIDKey{}, xid)
+	}
+
+	if !iok {
+		imd.Set(DefaultMetadataKey, xid)
+	}
+
+	if !ook {
+		omd.Set(DefaultMetadataKey, xid)
+	}
+
+	return ctx, nil
+}
+
+type hook struct{}
+
+func NewHook() *hook {
+	return &hook{}
+}
+
+func (w *hook) ServerHandler(next server.FuncHandler) server.FuncHandler {
+	return func(ctx context.Context, req server.Request, rsp interface{}) error {
+		var err error
+		if ctx, err = DefaultMetadataFunc(ctx); err != nil {
+			return err
+		}
+		return next(ctx, req, rsp)
+	}
+}
+
+func (w *hook) ClientCall(next client.FuncCall) client.FuncCall {
+	return func(ctx context.Context, req client.Request, rsp interface{}, opts ...client.CallOption) error {
+		var err error
+		if ctx, err = DefaultMetadataFunc(ctx); err != nil {
+			return err
+		}
+		return next(ctx, req, rsp, opts...)
+	}
+}
+
+func (w *hook) ClientStream(next client.FuncStream) client.FuncStream {
+	return func(ctx context.Context, req client.Request, opts ...client.CallOption) (client.Stream, error) {
+		var err error
+		if ctx, err = DefaultMetadataFunc(ctx); err != nil {
+			return nil, err
+		}
+		return next(ctx, req, opts...)
+	}
+}

hooks/requestid/requestid_test.go

@@ -0,0 +1,33 @@
+package requestid
+
+import (
+	"context"
+	"testing"
+
+	"go.unistack.org/micro/v4/metadata"
+)
+
+func TestDefaultMetadataFunc(t *testing.T) {
+	ctx := context.TODO()
+
+	nctx, err := DefaultMetadataFunc(ctx)
+	if err != nil {
+		t.Fatalf("%v", err)
+	}
+
+	imd, ok := metadata.FromIncomingContext(nctx)
+	if !ok {
+		t.Fatalf("md missing in incoming context")
+	}
+	omd, ok := metadata.FromOutgoingContext(nctx)
+	if !ok {
+		t.Fatalf("md missing in outgoing context")
+	}
+
+	_, iok := imd.Get(DefaultMetadataKey)
+	_, ook := omd.Get(DefaultMetadataKey)
+
+	if !iok || !ook {
+		t.Fatalf("missing metadata key value")
+	}
+}

hooks/validator/validator.go

@@ -0,0 +1,133 @@
+package validator
+
+import (
+	"context"
+
+	"go.unistack.org/micro/v4/client"
+	"go.unistack.org/micro/v4/errors"
+	"go.unistack.org/micro/v4/server"
+)
+
+var (
+	DefaultClientErrorFunc = func(req client.Request, rsp interface{}, err error) error {
+		if rsp != nil {
+			return errors.BadGateway(req.Service(), "%v", err)
+		}
+		return errors.BadRequest(req.Service(), "%v", err)
+	}
+
+	DefaultServerErrorFunc = func(req server.Request, rsp interface{}, err error) error {
+		if rsp != nil {
+			return errors.BadGateway(req.Service(), "%v", err)
+		}
+		return errors.BadRequest(req.Service(), "%v", err)
+	}
+)
+
+type (
+	ClientErrorFunc func(client.Request, interface{}, error) error
+	ServerErrorFunc func(server.Request, interface{}, error) error
+)
+
+// Options struct holds wrapper options
+type Options struct {
+	ClientErrorFn          ClientErrorFunc
+	ServerErrorFn          ServerErrorFunc
+	ClientValidateResponse bool
+	ServerValidateResponse bool
+}
+
+// Option func signature
+type Option func(*Options)
+
+func ClientValidateResponse(b bool) Option {
+	return func(o *Options) {
+		o.ClientValidateResponse = b
+	}
+}
+
+func ServerValidateResponse(b bool) Option {
+	return func(o *Options) {
+		o.ClientValidateResponse = b
+	}
+}
+
+func ClientReqErrorFn(fn ClientErrorFunc) Option {
+	return func(o *Options) {
+		o.ClientErrorFn = fn
+	}
+}
+
+func ServerErrorFn(fn ServerErrorFunc) Option {
+	return func(o *Options) {
+		o.ServerErrorFn = fn
+	}
+}
+
+func NewOptions(opts ...Option) Options {
+	options := Options{
+		ClientErrorFn: DefaultClientErrorFunc,
+		ServerErrorFn: DefaultServerErrorFunc,
+	}
+	for _, o := range opts {
+		o(&options)
+	}
+	return options
+}
+
+func NewHook(opts ...Option) *hook {
+	return &hook{opts: NewOptions(opts...)}
+}
+
+type validator interface {
+	Validate() error
+}
+
+type hook struct {
+	opts Options
+}
+
+func (w *hook) ClientCall(next client.FuncCall) client.FuncCall {
+	return func(ctx context.Context, req client.Request, rsp interface{}, opts ...client.CallOption) error {
+		if v, ok := req.Body().(validator); ok {
+			if err := v.Validate(); err != nil {
+				return w.opts.ClientErrorFn(req, nil, err)
+			}
+		}
+		err := next(ctx, req, rsp, opts...)
+		if v, ok := rsp.(validator); ok && w.opts.ClientValidateResponse {
+			if verr := v.Validate(); verr != nil {
+				return w.opts.ClientErrorFn(req, rsp, verr)
+			}
+		}
+		return err
+	}
+}
+
+func (w *hook) ClientStream(next client.FuncStream) client.FuncStream {
+	return func(ctx context.Context, req client.Request, opts ...client.CallOption) (client.Stream, error) {
+		if v, ok := req.Body().(validator); ok {
+			if err := v.Validate(); err != nil {
+				return nil, w.opts.ClientErrorFn(req, nil, err)
+			}
+		}
+		return next(ctx, req, opts...)
+	}
+}
+
+func (w *hook) ServerHandler(next server.FuncHandler) server.FuncHandler {
+	return func(ctx context.Context, req server.Request, rsp interface{}) error {
+		if v, ok := req.Body().(validator); ok {
+			if err := v.Validate(); err != nil {
+				return w.opts.ServerErrorFn(req, nil, err)
+			}
+		}
+		err := next(ctx, req, rsp)
+		if v, ok := rsp.(validator); ok && w.opts.ServerValidateResponse {
+			if verr := v.Validate(); verr != nil {
+				return w.opts.ServerErrorFn(req, rsp, verr)
+			}
+		}
+		return err
+	}
+}

logger/context.go

@@ -13,6 +13,15 @@ func FromContext(ctx context.Context) (Logger, bool) {
 	return l, ok
 }
 
+// MustContext returns logger from passed context or DefaultLogger if empty
+func MustContext(ctx context.Context) Logger {
+	l, ok := FromContext(ctx)
+	if !ok {
+		panic("missing logger")
+	}
+	return l
+}
+
 // NewContext stores logger into passed context
 func NewContext(ctx context.Context, l Logger) context.Context {
 	if ctx == nil {
@@ -20,3 +29,13 @@ func NewContext(ctx context.Context, l Logger) context.Context {
 	}
 	return context.WithValue(ctx, loggerKey{}, l)
 }
+
+// SetOption returns a function to setup a context with given value
+func SetOption(k, v interface{}) Option {
+	return func(o *Options) {
+		if o.Context == nil {
+			o.Context = context.Background()
+		}
+		o.Context = context.WithValue(o.Context, k, v)
+	}
+}

logger/context_test.go

@@ -40,3 +40,14 @@ func TestNewContext(t *testing.T) {
 		t.Fatal("NewContext not works")
 	}
 }
+
+func TestSetOption(t *testing.T) {
+	type key struct{}
+	o := SetOption(key{}, "test")
+	opts := &Options{}
+	o(opts)
+
+	if v, ok := opts.Context.Value(key{}).(string); !ok || v == "" {
+		t.Fatal("SetOption not works")
+	}
+}

logger/default.go

@@ -1,232 +0,0 @@
-package logger
-
-import (
-	"context"
-	"encoding/json"
-	"fmt"
-	"os"
-	"runtime"
-	"strings"
-	"sync"
-	"time"
-
-	"go.unistack.org/micro/v4/options"
-)
-
-type defaultLogger struct {
-	enc  *json.Encoder
-	opts Options
-	sync.RWMutex
-}
-
-// Init(opts...) should only overwrite provided options
-func (l *defaultLogger) Init(opts ...options.Option) error {
-	l.Lock()
-	for _, o := range opts {
-		o(&l.opts)
-	}
-	l.enc = json.NewEncoder(l.opts.Out)
-	// wrap the Log func
-	l.Unlock()
-	return nil
-}
-
-func (l *defaultLogger) String() string {
-	return "micro"
-}
-
-func (l *defaultLogger) Clone(opts ...options.Option) Logger {
-	newopts := NewOptions(opts...)
-	oldopts := l.opts
-	for _, o := range opts {
-		o(&newopts)
-		o(&oldopts)
-	}
-
-	l.Lock()
-	cl := &defaultLogger{opts: oldopts, enc: json.NewEncoder(l.opts.Out)}
-	l.Unlock()
-
-	return cl
-}
-
-func (l *defaultLogger) V(level Level) bool {
-	l.RLock()
-	ok := l.opts.Level.Enabled(level)
-	l.RUnlock()
-	return ok
-}
-
-func (l *defaultLogger) Level(level Level) {
-	l.Lock()
-	l.opts.Level = level
-	l.Unlock()
-}
-
-func (l *defaultLogger) Fields(fields ...interface{}) Logger {
-	l.RLock()
-	nl := &defaultLogger{opts: l.opts, enc: l.enc}
-	if len(fields) == 0 {
-		l.RUnlock()
-		return nl
-	} else if len(fields)%2 != 0 {
-		fields = fields[:len(fields)-1]
-	}
-	nl.opts.Fields = copyFields(l.opts.Fields)
-	nl.opts.Fields = append(nl.opts.Fields, fields...)
-	l.RUnlock()
-	return nl
-}
-
-func copyFields(src []interface{}) []interface{} {
-	dst := make([]interface{}, len(src))
-	copy(dst, src)
-	return dst
-}
-
-// logCallerfilePath returns a package/file:line description of the caller,
-// preserving only the leaf directory name and file name.
-func logCallerfilePath(loggingFilePath string) string {
-	// To make sure we trim the path correctly on Windows too, we
-	// counter-intuitively need to use '/' and *not* os.PathSeparator here,
-	// because the path given originates from Go stdlib, specifically
-	// runtime.Caller() which (as of Mar/17) returns forward slashes even on
-	// Windows.
-	//
-	// See https://github.com/golang/go/issues/3335
-	// and https://github.com/golang/go/issues/18151
-	//
-	// for discussion on the issue on Go side.
-	idx := strings.LastIndexByte(loggingFilePath, '/')
-	if idx == -1 {
-		return loggingFilePath
-	}
-	idx = strings.LastIndexByte(loggingFilePath[:idx], '/')
-	if idx == -1 {
-		return loggingFilePath
-	}
-	return loggingFilePath[idx+1:]
-}
-
-func (l *defaultLogger) Info(ctx context.Context, args ...interface{}) {
-	l.Log(ctx, InfoLevel, args...)
-}
-
-func (l *defaultLogger) Error(ctx context.Context, args ...interface{}) {
-	l.Log(ctx, ErrorLevel, args...)
-}
-
-func (l *defaultLogger) Debug(ctx context.Context, args ...interface{}) {
-	l.Log(ctx, DebugLevel, args...)
-}
-
-func (l *defaultLogger) Warn(ctx context.Context, args ...interface{}) {
-	l.Log(ctx, WarnLevel, args...)
-}
-
-func (l *defaultLogger) Trace(ctx context.Context, args ...interface{}) {
-	l.Log(ctx, TraceLevel, args...)
-}
-
-func (l *defaultLogger) Fatal(ctx context.Context, args ...interface{}) {
-	l.Log(ctx, FatalLevel, args...)
-	os.Exit(1)
-}
-
-func (l *defaultLogger) Infof(ctx context.Context, msg string, args ...interface{}) {
-	l.Logf(ctx, InfoLevel, msg, args...)
-}
-
-func (l *defaultLogger) Errorf(ctx context.Context, msg string, args ...interface{}) {
-	l.Logf(ctx, ErrorLevel, msg, args...)
-}
-
-func (l *defaultLogger) Debugf(ctx context.Context, msg string, args ...interface{}) {
-	l.Logf(ctx, DebugLevel, msg, args...)
-}
-
-func (l *defaultLogger) Warnf(ctx context.Context, msg string, args ...interface{}) {
-	l.Logf(ctx, WarnLevel, msg, args...)
-}
-
-func (l *defaultLogger) Tracef(ctx context.Context, msg string, args ...interface{}) {
-	l.Logf(ctx, TraceLevel, msg, args...)
-}
-
-func (l *defaultLogger) Fatalf(ctx context.Context, msg string, args ...interface{}) {
-	l.Logf(ctx, FatalLevel, msg, args...)
-	os.Exit(1)
-}
-
-func (l *defaultLogger) Log(ctx context.Context, level Level, args ...interface{}) {
-	if !l.V(level) {
-		return
-	}
-
-	l.RLock()
-	fields := copyFields(l.opts.Fields)
-	l.RUnlock()
-
-	fields = append(fields, "level", level.String())
-
-	if _, file, line, ok := runtime.Caller(l.opts.CallerSkipCount); ok {
-		fields = append(fields, "caller", fmt.Sprintf("%s:%d", logCallerfilePath(file), line))
-	}
-	fields = append(fields, "timestamp", time.Now().Format("2006-01-02 15:04:05"))
-
-	if len(args) > 0 {
-		fields = append(fields, "msg", fmt.Sprint(args...))
-	}
-
-	out := make(map[string]interface{}, len(fields)/2)
-	for i := 0; i < len(fields); i += 2 {
-		out[fields[i].(string)] = fields[i+1]
-	}
-	l.RLock()
-	_ = l.enc.Encode(out)
-	l.RUnlock()
-}
-
-func (l *defaultLogger) Logf(ctx context.Context, level Level, msg string, args ...interface{}) {
-	if !l.V(level) {
-		return
-	}
-
-	l.RLock()
-	fields := copyFields(l.opts.Fields)
-	l.RUnlock()
-
-	fields = append(fields, "level", level.String())
-
-	if _, file, line, ok := runtime.Caller(l.opts.CallerSkipCount); ok {
-		fields = append(fields, "caller", fmt.Sprintf("%s:%d", logCallerfilePath(file), line))
-	}
-
-	fields = append(fields, "timestamp", time.Now().Format("2006-01-02 15:04:05"))
-	if len(args) > 0 {
-		fields = append(fields, "msg", fmt.Sprintf(msg, args...))
-	} else if msg != "" {
-		fields = append(fields, "msg", msg)
-	}
-
-	out := make(map[string]interface{}, len(fields)/2)
-	for i := 0; i < len(fields); i += 2 {
-		out[fields[i].(string)] = fields[i+1]
-	}
-	l.RLock()
-	_ = l.enc.Encode(out)
-	l.RUnlock()
-}
-
-func (l *defaultLogger) Options() Options {
-	return l.opts
-}
-
-// NewLogger builds a new logger based on options
-func NewLogger(opts ...options.Option) Logger {
-	l := &defaultLogger{
-		opts: NewOptions(opts...),
-	}
-	l.enc = json.NewEncoder(l.opts.Out)
-	return l
-}

logger/logger.go

@@ -1,28 +1,27 @@
 // Package logger provides a log interface
-package logger // import "go.unistack.org/micro/v4/logger"
+package logger
 
 import (
 	"context"
-	"os"
-
-	"go.unistack.org/micro/v4/options"
 )
 
+type ContextAttrFunc func(ctx context.Context) []interface{}
+
+var DefaultContextAttrFuncs []ContextAttrFunc
+
 var (
 	// DefaultLogger variable
-	DefaultLogger = NewLogger(WithLevel(ParseLevel(os.Getenv("MICRO_LOG_LEVEL"))))
+	DefaultLogger = NewLogger()
 	// DefaultLevel used by logger
 	DefaultLevel = InfoLevel
-	// DefaultCallerSkipCount used by logger
-	DefaultCallerSkipCount = 2
 )
 
 // Logger is a generic logging interface
 type Logger interface {
 	// Init initialises options
-	Init(opts ...options.Option) error
+	Init(opts ...Option) error
 	// Clone create logger copy with new options
-	Clone(opts ...options.Option) Logger
+	Clone(opts ...Option) Logger
 	// V compare provided verbosity level with current log level
 	V(level Level) bool
 	// Level sets the log level for logger
@@ -32,111 +31,24 @@ type Logger interface {
 	// Fields set fields to always be logged with keyval pairs
 	Fields(fields ...interface{}) Logger
 	// Info level message
-	Info(ctx context.Context, args ...interface{})
+	Info(ctx context.Context, msg string, args ...interface{})
 	// Trace level message
-	Trace(ctx context.Context, args ...interface{})
+	Trace(ctx context.Context, msg string, args ...interface{})
 	// Debug level message
-	Debug(ctx context.Context, args ...interface{})
+	Debug(ctx context.Context, msg string, args ...interface{})
 	// Warn level message
-	Warn(ctx context.Context, args ...interface{})
+	Warn(ctx context.Context, msg string, args ...interface{})
 	// Error level message
-	Error(ctx context.Context, args ...interface{})
+	Error(ctx context.Context, msg string, args ...interface{})
 	// Fatal level message
-	Fatal(ctx context.Context, args ...interface{})
+	Fatal(ctx context.Context, msg string, args ...interface{})
-	// Infof level message
-	Infof(ctx context.Context, msg string, args ...interface{})
-	// Tracef level message
-	Tracef(ctx context.Context, msg string, args ...interface{})
-	// Debug level message
-	Debugf(ctx context.Context, msg string, args ...interface{})
-	// Warn level message
-	Warnf(ctx context.Context, msg string, args ...interface{})
-	// Error level message
-	Errorf(ctx context.Context, msg string, args ...interface{})
-	// Fatal level message
-	Fatalf(ctx context.Context, msg string, args ...interface{})
 	// Log logs message with needed level
-	Log(ctx context.Context, level Level, args ...interface{})
+	Log(ctx context.Context, level Level, msg string, args ...interface{})
-	// Logf logs message with needed level
+	// Name returns broker instance name
-	Logf(ctx context.Context, level Level, msg string, args ...interface{})
+	Name() string
-	// String returns the name of logger
+	// String returns the type of logger
 	String() string
 }
 
 // Field contains keyval pair
 type Field interface{}
-
-// Info writes msg to default logger on info level
-func Info(ctx context.Context, args ...interface{}) {
-	DefaultLogger.Info(ctx, args...)
-}
-
-// Error writes msg to default logger on error level
-func Error(ctx context.Context, args ...interface{}) {
-	DefaultLogger.Error(ctx, args...)
-}
-
-// Debug writes msg to default logger on debug level
-func Debug(ctx context.Context, args ...interface{}) {
-	DefaultLogger.Debug(ctx, args...)
-}
-
-// Warn writes msg to default logger on warn level
-func Warn(ctx context.Context, args ...interface{}) {
-	DefaultLogger.Warn(ctx, args...)
-}
-
-// Trace writes msg to default logger on trace level
-func Trace(ctx context.Context, args ...interface{}) {
-	DefaultLogger.Trace(ctx, args...)
-}
-
-// Fatal writes msg to default logger on fatal level
-func Fatal(ctx context.Context, args ...interface{}) {
-	DefaultLogger.Fatal(ctx, args...)
-}
-
-// Infof writes formatted msg to default logger on info level
-func Infof(ctx context.Context, msg string, args ...interface{}) {
-	DefaultLogger.Infof(ctx, msg, args...)
-}
-
-// Errorf writes formatted msg to default logger on error level
-func Errorf(ctx context.Context, msg string, args ...interface{}) {
-	DefaultLogger.Errorf(ctx, msg, args...)
-}
-
-// Debugf writes formatted msg to default logger on debug level
-func Debugf(ctx context.Context, msg string, args ...interface{}) {
-	DefaultLogger.Debugf(ctx, msg, args...)
-}
-
-// Warnf writes formatted msg to default logger on warn level
-func Warnf(ctx context.Context, msg string, args ...interface{}) {
-	DefaultLogger.Warnf(ctx, msg, args...)
-}
-
-// Tracef writes formatted msg to default logger on trace level
-func Tracef(ctx context.Context, msg string, args ...interface{}) {
-	DefaultLogger.Tracef(ctx, msg, args...)
-}
-
-// Fatalf writes formatted msg to default logger on fatal level
-func Fatalf(ctx context.Context, msg string, args ...interface{}) {
-	DefaultLogger.Fatalf(ctx, msg, args...)
-}
-
-// V returns true if passed level enabled in default logger
-func V(level Level) bool {
-	return DefaultLogger.V(level)
-}
-
-// Init initialize logger
-func Init(opts ...options.Option) error {
-	return DefaultLogger.Init(opts...)
-}
-
-// Fields create logger with specific fields
-func Fields(fields ...interface{}) Logger {
-	return DefaultLogger.Fields(fields...)
-}

logger/logger_test.go

@@ -1,138 +0,0 @@
-package logger
-
-import (
-	"bytes"
-	"context"
-	"log"
-	"testing"
-)
-
-func TestContext(t *testing.T) {
-	ctx := context.TODO()
-	buf := bytes.NewBuffer(nil)
-	l := NewLogger(WithLevel(TraceLevel), WithOutput(buf))
-	if err := l.Init(); err != nil {
-		t.Fatal(err)
-	}
-
-	nl, ok := FromContext(NewContext(ctx, l.Fields("key", "val")))
-	if !ok {
-		t.Fatal("context without logger")
-	}
-	nl.Info(ctx, "message")
-	if !bytes.Contains(buf.Bytes(), []byte(`"key":"val"`)) {
-		t.Fatalf("logger fields not works, buf contains: %s", buf.Bytes())
-	}
-}
-
-func TestFields(t *testing.T) {
-	ctx := context.TODO()
-	buf := bytes.NewBuffer(nil)
-	l := NewLogger(WithLevel(TraceLevel), WithOutput(buf))
-	if err := l.Init(); err != nil {
-		t.Fatal(err)
-	}
-
-	nl := l.Fields("key", "val")
-
-	nl.Info(ctx, "message")
-	if !bytes.Contains(buf.Bytes(), []byte(`"key":"val"`)) {
-		t.Fatalf("logger fields not works, buf contains: %s", buf.Bytes())
-	}
-}
-
-func TestFromContextWithFields(t *testing.T) {
-	ctx := context.TODO()
-	buf := bytes.NewBuffer(nil)
-	var ok bool
-	l := NewLogger(WithLevel(TraceLevel), WithOutput(buf))
-	if err := l.Init(); err != nil {
-		t.Fatal(err)
-	}
-	nl := l.Fields("key", "val")
-
-	ctx = NewContext(ctx, nl)
-
-	l, ok = FromContext(ctx)
-	if !ok {
-		t.Fatalf("context does not have logger")
-	}
-
-	l.Info(ctx, "message")
-	if !bytes.Contains(buf.Bytes(), []byte(`"key":"val"`)) {
-		t.Fatalf("logger fields not works, buf contains: %s", buf.Bytes())
-	}
-}
-
-func TestClone(t *testing.T) {
-	ctx := context.TODO()
-	buf := bytes.NewBuffer(nil)
-	l := NewLogger(WithLevel(TraceLevel), WithOutput(buf))
-	if err := l.Init(); err != nil {
-		t.Fatal(err)
-	}
-	nl := l.Clone(WithLevel(ErrorLevel))
-	if err := nl.Init(); err != nil {
-		t.Fatal(err)
-	}
-	nl.Info(ctx, "info message")
-	if len(buf.Bytes()) != 0 {
-		t.Fatal("message must not be logged")
-	}
-	l.Info(ctx, "info message")
-	if len(buf.Bytes()) == 0 {
-		t.Fatal("message must be logged")
-	}
-}
-
-func TestRedirectStdLogger(t *testing.T) {
-	buf := bytes.NewBuffer(nil)
-	l := NewLogger(WithLevel(TraceLevel), WithOutput(buf))
-	if err := l.Init(); err != nil {
-		t.Fatal(err)
-	}
-	fn := RedirectStdLogger(l, ErrorLevel)
-	defer fn()
-	log.Print("test")
-	if !bytes.Contains(buf.Bytes(), []byte(`"level":"error","msg":"test","timestamp"`)) {
-		t.Fatalf("logger error, buf %s", buf.Bytes())
-	}
-}
-
-func TestStdLogger(t *testing.T) {
-	buf := bytes.NewBuffer(nil)
-	l := NewLogger(WithLevel(TraceLevel), WithOutput(buf))
-	if err := l.Init(); err != nil {
-		t.Fatal(err)
-	}
-	lg := NewStdLogger(l, ErrorLevel)
-	lg.Print("test")
-	if !bytes.Contains(buf.Bytes(), []byte(`"level":"error","msg":"test","timestamp"`)) {
-		t.Fatalf("logger error, buf %s", buf.Bytes())
-	}
-}
-
-func TestLogger(t *testing.T) {
-	ctx := context.TODO()
-	buf := bytes.NewBuffer(nil)
-	l := NewLogger(WithLevel(TraceLevel), WithOutput(buf))
-	if err := l.Init(); err != nil {
-		t.Fatal(err)
-	}
-	l.Trace(ctx, "trace_msg1")
-	l.Warn(ctx, "warn_msg1")
-	l.Fields("error", "test").Info(ctx, "error message")
-	l.Warn(ctx, "first", " ", "second")
-	if !bytes.Contains(buf.Bytes(), []byte(`"level":"trace","msg":"trace_msg1"`)) {
-		t.Fatalf("logger error, buf %s", buf.Bytes())
-	}
-	if !bytes.Contains(buf.Bytes(), []byte(`"warn","msg":"warn_msg1"`)) {
-		t.Fatalf("logger error, buf %s", buf.Bytes())
-	}
-	if !bytes.Contains(buf.Bytes(), []byte(`"error":"test","level":"info","msg":"error message"`)) {
-		t.Fatalf("logger error, buf %s", buf.Bytes())
-	}
-	if !bytes.Contains(buf.Bytes(), []byte(`"level":"warn","msg":"first second"`)) {
-		t.Fatalf("logger error, buf %s", buf.Bytes())
-	}
-}

logger/noop.go

@@ -0,0 +1,78 @@
+package logger
+
+import (
+	"context"
+)
+
+const (
+	defaultCallerSkipCount = 2
+)
+
+type noopLogger struct {
+	opts Options
+}
+
+func NewLogger(opts ...Option) Logger {
+	options := NewOptions(opts...)
+	options.CallerSkipCount = defaultCallerSkipCount
+	return &noopLogger{opts: options}
+}
+
+func (l *noopLogger) V(_ Level) bool {
+	return false
+}
+
+func (l *noopLogger) Level(_ Level) {
+}
+
+func (l *noopLogger) Name() string {
+	return l.opts.Name
+}
+
+func (l *noopLogger) Init(opts ...Option) error {
+	for _, o := range opts {
+		o(&l.opts)
+	}
+	return nil
+}
+
+func (l *noopLogger) Clone(opts ...Option) Logger {
+	nl := &noopLogger{opts: l.opts}
+	for _, o := range opts {
+		o(&nl.opts)
+	}
+	return nl
+}
+
+func (l *noopLogger) Fields(_ ...interface{}) Logger {
+	return l
+}
+
+func (l *noopLogger) Options() Options {
+	return l.opts
+}
+
+func (l *noopLogger) String() string {
+	return "noop"
+}
+
+func (l *noopLogger) Log(ctx context.Context, lvl Level, msg string, attrs ...interface{}) {
+}
+
+func (l *noopLogger) Info(ctx context.Context, msg string, attrs ...interface{}) {
+}
+
+func (l *noopLogger) Debug(ctx context.Context, msg string, attrs ...interface{}) {
+}
+
+func (l *noopLogger) Error(ctx context.Context, msg string, attrs ...interface{}) {
+}
+
+func (l *noopLogger) Trace(ctx context.Context, msg string, attrs ...interface{}) {
+}
+
+func (l *noopLogger) Warn(ctx context.Context, msg string, attrs ...interface{}) {
+}
+
+func (l *noopLogger) Fatal(ctx context.Context, msg string, attrs ...interface{}) {
+}

logger/options.go

@@ -3,66 +3,228 @@ package logger
 import (
 	"context"
 	"io"
+	"log/slog"
 	"os"
+	"slices"
+	"time"
 
-	"go.unistack.org/micro/v4/options"
+	"go.unistack.org/micro/v4/meter"
 )
 
+// Option func signature
+type Option func(*Options)
+
 // Options holds logger options
 type Options struct {
+	// TimeKey is the key used for the time of the log call
+	TimeKey string
+	// LevelKey is the key used for the level of the log call
+	LevelKey string
+	// ErroreKey is the key used for the error of the log call
+	ErrorKey string
+	// MessageKey is the key used for the message of the log call
+	MessageKey string
+	// SourceKey is the key used for the source file and line of the log call
+	SourceKey string
+	// StacktraceKey is the key used for the stacktrace
+	StacktraceKey string
+	// Name holds the logger name
+	Name string
 	// Out holds the output writer
 	Out io.Writer
 	// Context holds exernal options
 	Context context.Context
+	// Meter used to count logs for specific level
+	Meter meter.Meter
+	// TimeFunc used to obtain current time
+	TimeFunc func() time.Time
 	// Fields holds additional metadata
 	Fields []interface{}
-	// Name holds the logger name
+	// ContextAttrFuncs contains funcs that executed before log func on context
-	Name string
+	ContextAttrFuncs []ContextAttrFunc
+	// callerSkipCount number of frmaes to skip
+	CallerSkipCount int
 	// The logging level the logger should log
 	Level Level
-	// CallerSkipCount number of frmaes to skip
+	// AddSource enabled writing source file and position in log
-	CallerSkipCount int
+	AddSource bool
+	// AddStacktrace controls writing of stacktaces on error
+	AddStacktrace bool
+	// DedupKeys deduplicate keys in log output
+	DedupKeys bool
 }
 
 // NewOptions creates new options struct
-func NewOptions(opts ...options.Option) Options {
+func NewOptions(opts ...Option) Options {
 	options := Options{
 		Level:            DefaultLevel,
 		Fields:           make([]interface{}, 0, 6),
 		Out:              os.Stderr,
-		CallerSkipCount: DefaultCallerSkipCount,
 		Context:          context.Background(),
+		ContextAttrFuncs: DefaultContextAttrFuncs,
+		AddSource:        true,
+		TimeFunc:         time.Now,
+		Meter:            meter.DefaultMeter,
 	}
+
+	WithMicroKeys()(&options)
+
 	for _, o := range opts {
 		o(&options)
 	}
+
 	return options
 }
 
+// WithContextAttrFuncs appends default funcs for the context attrs filler
+func WithContextAttrFuncs(fncs ...ContextAttrFunc) Option {
+	return func(o *Options) {
+		o.ContextAttrFuncs = append(o.ContextAttrFuncs, fncs...)
+	}
+}
+
+// WithDedupKeys dont log duplicate keys
+func WithDedupKeys(b bool) Option {
+	return func(o *Options) {
+		o.DedupKeys = b
+	}
+}
+
+// WithAddFields add fields for the logger
+func WithAddFields(fields ...interface{}) Option {
+	return func(o *Options) {
+		if o.DedupKeys {
+			for i := 0; i < len(o.Fields); i += 2 {
+				for j := 0; j < len(fields); j += 2 {
+					iv, iok := o.Fields[i].(string)
+					jv, jok := fields[j].(string)
+					if iok && jok && iv == jv {
+						o.Fields[i+1] = fields[j+1]
+						fields = slices.Delete(fields, j, j+2)
+					}
+				}
+			}
+			if len(fields) > 0 {
+				o.Fields = append(o.Fields, fields...)
+			}
+		} else {
+			o.Fields = append(o.Fields, fields...)
+		}
+	}
+}
+
 // WithFields set default fields for the logger
-func WithFields(fields ...interface{}) options.Option {
+func WithFields(fields ...interface{}) Option {
-	return func(src interface{}) error {
+	return func(o *Options) {
-		return options.Set(src, fields, ".Fields")
+		o.Fields = fields
 	}
 }
 
 // WithLevel set default level for the logger
-func WithLevel(lvl Level) options.Option {
+func WithLevel(level Level) Option {
-	return func(src interface{}) error {
+	return func(o *Options) {
-		return options.Set(src, lvl, ".Level")
+		o.Level = level
 	}
 }
 
 // WithOutput set default output writer for the logger
-func WithOutput(out io.Writer) options.Option {
+func WithOutput(out io.Writer) Option {
-	return func(src interface{}) error {
+	return func(o *Options) {
-		return options.Set(src, out, ".Out")
+		o.Out = out
 	}
 }
 
-// WithCallerSkipCount set frame count to skip
+// WithAddStacktrace controls writing stacktrace on error
-func WithCallerSkipCount(c int) options.Option {
+func WithAddStacktrace(v bool) Option {
-	return func(src interface{}) error {
+	return func(o *Options) {
-		return options.Set(src, c, ".CallerSkipCount")
+		o.AddStacktrace = v
+	}
+}
+
+// WithAddSource controls writing source file and pos in log
+func WithAddSource(v bool) Option {
+	return func(o *Options) {
+		o.AddSource = v
+	}
+}
+
+// WithContext set context
+func WithContext(ctx context.Context) Option {
+	return func(o *Options) {
+		o.Context = ctx
+	}
+}
+
+// WithName sets the name
+func WithName(n string) Option {
+	return func(o *Options) {
+		o.Name = n
+	}
+}
+
+// WithMeter sets the meter
+func WithMeter(m meter.Meter) Option {
+	return func(o *Options) {
+		o.Meter = m
+	}
+}
+
+// WithTimeFunc sets the func to obtain current time
+func WithTimeFunc(fn func() time.Time) Option {
+	return func(o *Options) {
+		o.TimeFunc = fn
+	}
+}
+
+func WithZapKeys() Option {
+	return func(o *Options) {
+		o.TimeKey = "@timestamp"
+		o.LevelKey = slog.LevelKey
+		o.MessageKey = slog.MessageKey
+		o.SourceKey = "caller"
+		o.StacktraceKey = "stacktrace"
+		o.ErrorKey = "error"
+	}
+}
+
+func WithZerologKeys() Option {
+	return func(o *Options) {
+		o.TimeKey = slog.TimeKey
+		o.LevelKey = slog.LevelKey
+		o.MessageKey = "message"
+		o.SourceKey = "caller"
+		o.StacktraceKey = "stacktrace"
+		o.ErrorKey = "error"
+	}
+}
+
+func WithSlogKeys() Option {
+	return func(o *Options) {
+		o.TimeKey = slog.TimeKey
+		o.LevelKey = slog.LevelKey
+		o.MessageKey = slog.MessageKey
+		o.SourceKey = slog.SourceKey
+		o.StacktraceKey = "stacktrace"
+		o.ErrorKey = "error"
+	}
+}
+
+func WithMicroKeys() Option {
+	return func(o *Options) {
+		o.TimeKey = "timestamp"
+		o.LevelKey = slog.LevelKey
+		o.MessageKey = slog.MessageKey
+		o.SourceKey = "caller"
+		o.StacktraceKey = "stacktrace"
+		o.ErrorKey = "error"
+	}
+}
+
+// WithAddCallerSkipCount add skip count for copy logger
+func WithAddCallerSkipCount(n int) Option {
+	return func(o *Options) {
+		if n > 0 {
+			o.CallerSkipCount += n
+		}
 	}
 }

logger/slog/slog.go

@@ -0,0 +1,375 @@
+package slog
+
+import (
+	"context"
+	"io"
+	"log/slog"
+	"os"
+	"reflect"
+	"regexp"
+	"runtime"
+	"strconv"
+	"sync"
+	"sync/atomic"
+	"time"
+
+	"go.unistack.org/micro/v4/logger"
+	"go.unistack.org/micro/v4/semconv"
+	"go.unistack.org/micro/v4/tracer"
+)
+
+const (
+	badKey = "!BADKEY"
+	// defaultCallerSkipCount used by logger
+	defaultCallerSkipCount = 3
+	timeFormat             = "2006-01-02T15:04:05.000000000Z07:00"
+)
+
+var reTrace = regexp.MustCompile(`.*/slog/logger\.go.*\n`)
+
+var (
+	traceValue = slog.StringValue("trace")
+	debugValue = slog.StringValue("debug")
+	infoValue  = slog.StringValue("info")
+	warnValue  = slog.StringValue("warn")
+	errorValue = slog.StringValue("error")
+	fatalValue = slog.StringValue("fatal")
+)
+
+type wrapper struct {
+	h     slog.Handler
+	level atomic.Int64
+}
+
+func (h *wrapper) Enabled(ctx context.Context, level slog.Level) bool {
+	return level >= slog.Level(int(h.level.Load()))
+}
+
+func (h *wrapper) Handle(ctx context.Context, rec slog.Record) error {
+	return h.h.Handle(ctx, rec)
+}
+
+func (h *wrapper) WithAttrs(attrs []slog.Attr) slog.Handler {
+	return h.h.WithAttrs(attrs)
+}
+
+func (h *wrapper) WithGroup(name string) slog.Handler {
+	return h.h.WithGroup(name)
+}
+
+func (s *slogLogger) renameAttr(_ []string, a slog.Attr) slog.Attr {
+	switch a.Key {
+	case slog.SourceKey:
+		source := a.Value.Any().(*slog.Source)
+		a.Value = slog.StringValue(source.File + ":" + strconv.Itoa(source.Line))
+		a.Key = s.opts.SourceKey
+	case slog.TimeKey:
+		a.Key = s.opts.TimeKey
+		a.Value = slog.StringValue(a.Value.Time().Format(timeFormat))
+	case slog.MessageKey:
+		a.Key = s.opts.MessageKey
+	case slog.LevelKey:
+		level := a.Value.Any().(slog.Level)
+		lvl := slogToLoggerLevel(level)
+		a.Key = s.opts.LevelKey
+		switch {
+		case lvl < logger.DebugLevel:
+			a.Value = traceValue
+		case lvl < logger.InfoLevel:
+			a.Value = debugValue
+		case lvl < logger.WarnLevel:
+			a.Value = infoValue
+		case lvl < logger.ErrorLevel:
+			a.Value = warnValue
+		case lvl < logger.FatalLevel:
+			a.Value = errorValue
+		case lvl >= logger.FatalLevel:
+			a.Value = fatalValue
+		default:
+			a.Value = infoValue
+		}
+	}
+
+	return a
+}
+
+type slogLogger struct {
+	handler *wrapper
+	opts    logger.Options
+	mu      sync.RWMutex
+}
+
+func (s *slogLogger) Clone(opts ...logger.Option) logger.Logger {
+	s.mu.RLock()
+	options := s.opts
+	s.mu.RUnlock()
+
+	for _, o := range opts {
+		o(&options)
+	}
+
+	if len(options.ContextAttrFuncs) == 0 {
+		options.ContextAttrFuncs = logger.DefaultContextAttrFuncs
+	}
+
+	attrs, _ := s.argsAttrs(options.Fields)
+	l := &slogLogger{
+		handler: &wrapper{h: s.handler.h.WithAttrs(attrs)},
+		opts:    options,
+	}
+	l.handler.level.Store(int64(loggerToSlogLevel(options.Level)))
+
+	return l
+}
+
+func (s *slogLogger) V(level logger.Level) bool {
+	s.mu.Lock()
+	v := s.opts.Level.Enabled(level)
+	s.mu.Unlock()
+	return v
+}
+
+func (s *slogLogger) Level(level logger.Level) {
+	s.mu.Lock()
+	s.opts.Level = level
+	s.handler.level.Store(int64(loggerToSlogLevel(level)))
+	s.mu.Unlock()
+}
+
+func (s *slogLogger) Options() logger.Options {
+	return s.opts
+}
+
+func (s *slogLogger) Fields(fields ...interface{}) logger.Logger {
+	s.mu.RLock()
+	options := s.opts
+	s.mu.RUnlock()
+
+	l := &slogLogger{opts: options}
+	logger.WithAddFields(fields...)(&l.opts)
+
+	if len(options.ContextAttrFuncs) == 0 {
+		options.ContextAttrFuncs = logger.DefaultContextAttrFuncs
+	}
+
+	attrs, _ := s.argsAttrs(fields)
+	l.handler = &wrapper{h: s.handler.h.WithAttrs(attrs)}
+	l.handler.level.Store(int64(loggerToSlogLevel(l.opts.Level)))
+
+	return l
+}
+
+func (s *slogLogger) Init(opts ...logger.Option) error {
+	s.mu.Lock()
+
+	for _, o := range opts {
+		o(&s.opts)
+	}
+
+	if len(s.opts.ContextAttrFuncs) == 0 {
+		s.opts.ContextAttrFuncs = logger.DefaultContextAttrFuncs
+	}
+
+	handleOpt := &slog.HandlerOptions{
+		ReplaceAttr: s.renameAttr,
+		Level:       loggerToSlogLevel(logger.TraceLevel),
+		AddSource:   s.opts.AddSource,
+	}
+
+	attrs, _ := s.argsAttrs(s.opts.Fields)
+
+	var h slog.Handler
+	if s.opts.Context != nil {
+		if v, ok := s.opts.Context.Value(handlerKey{}).(slog.Handler); ok && v != nil {
+			h = v
+		}
+
+		if fn := s.opts.Context.Value(handlerFnKey{}); fn != nil {
+			if rfn := reflect.ValueOf(fn); rfn.Kind() == reflect.Func {
+				if ret := rfn.Call([]reflect.Value{reflect.ValueOf(s.opts.Out), reflect.ValueOf(handleOpt)}); len(ret) == 1 {
+					if iface, ok := ret[0].Interface().(slog.Handler); ok && iface != nil {
+						h = iface
+					}
+				}
+			}
+		}
+	}
+
+	if h == nil {
+		h = slog.NewJSONHandler(s.opts.Out, handleOpt)
+	}
+
+	s.handler = &wrapper{h: h.WithAttrs(attrs)}
+	s.handler.level.Store(int64(loggerToSlogLevel(s.opts.Level)))
+	s.mu.Unlock()
+
+	return nil
+}
+
+func (s *slogLogger) Log(ctx context.Context, lvl logger.Level, msg string, attrs ...interface{}) {
+	s.printLog(ctx, lvl, msg, attrs...)
+}
+
+func (s *slogLogger) Info(ctx context.Context, msg string, attrs ...interface{}) {
+	s.printLog(ctx, logger.InfoLevel, msg, attrs...)
+}
+
+func (s *slogLogger) Debug(ctx context.Context, msg string, attrs ...interface{}) {
+	s.printLog(ctx, logger.DebugLevel, msg, attrs...)
+}
+
+func (s *slogLogger) Trace(ctx context.Context, msg string, attrs ...interface{}) {
+	s.printLog(ctx, logger.TraceLevel, msg, attrs...)
+}
+
+func (s *slogLogger) Error(ctx context.Context, msg string, attrs ...interface{}) {
+	s.printLog(ctx, logger.ErrorLevel, msg, attrs...)
+}
+
+func (s *slogLogger) Fatal(ctx context.Context, msg string, attrs ...interface{}) {
+	s.printLog(ctx, logger.FatalLevel, msg, attrs...)
+	if closer, ok := s.opts.Out.(io.Closer); ok {
+		closer.Close()
+	}
+	time.Sleep(1 * time.Second)
+	os.Exit(1)
+}
+
+func (s *slogLogger) Warn(ctx context.Context, msg string, attrs ...interface{}) {
+	s.printLog(ctx, logger.WarnLevel, msg, attrs...)
+}
+
+func (s *slogLogger) Name() string {
+	return s.opts.Name
+}
+
+func (s *slogLogger) String() string {
+	return "slog"
+}
+
+func (s *slogLogger) printLog(ctx context.Context, lvl logger.Level, msg string, args ...interface{}) {
+	if !s.V(lvl) {
+		return
+	}
+	var argError error
+
+	s.opts.Meter.Counter(semconv.LoggerMessageTotal, "level", lvl.String()).Inc()
+
+	attrs, err := s.argsAttrs(args)
+	if err != nil {
+		argError = err
+	}
+	if argError != nil {
+		if span, ok := tracer.SpanFromContext(ctx); ok {
+			span.SetStatus(tracer.SpanStatusError, argError.Error())
+		}
+	}
+
+	for _, fn := range s.opts.ContextAttrFuncs {
+		ctxAttrs, err := s.argsAttrs(fn(ctx))
+		if err != nil {
+			argError = err
+		}
+		attrs = append(attrs, ctxAttrs...)
+	}
+	if argError != nil {
+		if span, ok := tracer.SpanFromContext(ctx); ok {
+			span.SetStatus(tracer.SpanStatusError, argError.Error())
+		}
+	}
+
+	if s.opts.AddStacktrace && (lvl == logger.FatalLevel || lvl == logger.ErrorLevel) {
+		stackInfo := make([]byte, 1024*1024)
+		if stackSize := runtime.Stack(stackInfo, false); stackSize > 0 {
+			traceLines := reTrace.Split(string(stackInfo[:stackSize]), -1)
+			if len(traceLines) != 0 {
+				attrs = append(attrs, slog.String(s.opts.StacktraceKey, traceLines[len(traceLines)-1]))
+			}
+		}
+	}
+
+	var pcs [1]uintptr
+	runtime.Callers(s.opts.CallerSkipCount, pcs[:]) // skip [Callers, printLog, LogLvlMethod]
+	r := slog.NewRecord(s.opts.TimeFunc(), loggerToSlogLevel(lvl), msg, pcs[0])
+	r.AddAttrs(attrs...)
+	_ = s.handler.Handle(ctx, r)
+}
+
+func NewLogger(opts ...logger.Option) logger.Logger {
+	s := &slogLogger{
+		opts: logger.NewOptions(opts...),
+	}
+	s.opts.CallerSkipCount = defaultCallerSkipCount
+
+	return s
+}
+
+func loggerToSlogLevel(level logger.Level) slog.Level {
+	switch level {
+	case logger.DebugLevel:
+		return slog.LevelDebug
+	case logger.WarnLevel:
+		return slog.LevelWarn
+	case logger.ErrorLevel:
+		return slog.LevelError
+	case logger.TraceLevel:
+		return slog.LevelDebug - 1
+	case logger.FatalLevel:
+		return slog.LevelError + 1
+	default:
+		return slog.LevelInfo
+	}
+}
+
+func slogToLoggerLevel(level slog.Level) logger.Level {
+	switch level {
+	case slog.LevelDebug:
+		return logger.DebugLevel
+	case slog.LevelWarn:
+		return logger.WarnLevel
+	case slog.LevelError:
+		return logger.ErrorLevel
+	case slog.LevelDebug - 1:
+		return logger.TraceLevel
+	case slog.LevelError + 1:
+		return logger.FatalLevel
+	default:
+		return logger.InfoLevel
+	}
+}
+
+func (s *slogLogger) argsAttrs(args []interface{}) ([]slog.Attr, error) {
+	attrs := make([]slog.Attr, 0, len(args))
+	var err error
+
+	for idx := 0; idx < len(args); idx++ {
+		switch arg := args[idx].(type) {
+		case slog.Attr:
+			attrs = append(attrs, arg)
+		case string:
+			if idx+1 < len(args) {
+				attrs = append(attrs, slog.Any(arg, args[idx+1]))
+				idx++
+			} else {
+				attrs = append(attrs, slog.String(badKey, arg))
+			}
+		case error:
+			attrs = append(attrs, slog.String(s.opts.ErrorKey, arg.Error()))
+			err = arg
+		}
+	}
+
+	return attrs, err
+}
+
+type handlerKey struct{}
+
+func WithHandler(h slog.Handler) logger.Option {
+	return logger.SetOption(handlerKey{}, h)
+}
+
+type handlerFnKey struct{}
+
+func WithHandlerFunc(fn any) logger.Option {
+	return logger.SetOption(handlerFnKey{}, fn)
+}

logger/slog/slog_test.go

@@ -0,0 +1,454 @@
+package slog
+
+import (
+	"bytes"
+	"context"
+	"errors"
+	"fmt"
+	"log"
+	"log/slog"
+	"strings"
+	"testing"
+	"time"
+
+	"github.com/google/uuid"
+	"go.unistack.org/micro/v4/logger"
+	"go.unistack.org/micro/v4/metadata"
+	"go.unistack.org/micro/v4/util/buffer"
+)
+
+// always first to have proper check
+func TestStacktrace(t *testing.T) {
+	ctx := context.TODO()
+	buf := bytes.NewBuffer(nil)
+	l := NewLogger(logger.WithLevel(logger.DebugLevel), logger.WithOutput(buf),
+		WithHandlerFunc(slog.NewTextHandler),
+		logger.WithAddStacktrace(true),
+	)
+	if err := l.Init(logger.WithFields("key1", "val1")); err != nil {
+		t.Fatal(err)
+	}
+
+	l.Error(ctx, "msg1", errors.New("err"))
+
+	if !bytes.Contains(buf.Bytes(), []byte(`slog_test.go:32`)) {
+		t.Fatalf("logger error not works, buf contains: %s", buf.Bytes())
+	}
+}
+
+func TestDelayedBuffer(t *testing.T) {
+	ctx := context.TODO()
+	buf := bytes.NewBuffer(nil)
+	dbuf := buffer.NewDelayedBuffer(100, 100*time.Millisecond, buf)
+	l := NewLogger(logger.WithLevel(logger.ErrorLevel), logger.WithOutput(dbuf),
+		WithHandlerFunc(slog.NewTextHandler),
+		logger.WithAddStacktrace(true),
+	)
+	if err := l.Init(logger.WithFields("key1", "val1")); err != nil {
+		t.Fatal(err)
+	}
+
+	l.Error(ctx, "msg1", errors.New("err"))
+	time.Sleep(120 * time.Millisecond)
+	if !bytes.Contains(buf.Bytes(), []byte(`key1=val1`)) {
+		t.Fatalf("logger delayed buffer not works, buf contains: %s", buf.Bytes())
+	}
+}
+
+func TestTime(t *testing.T) {
+	ctx := context.TODO()
+	buf := bytes.NewBuffer(nil)
+	l := NewLogger(logger.WithLevel(logger.ErrorLevel), logger.WithOutput(buf),
+		WithHandlerFunc(slog.NewTextHandler),
+		logger.WithAddStacktrace(true),
+		logger.WithTimeFunc(func() time.Time {
+			return time.Unix(0, 0)
+		}),
+	)
+	if err := l.Init(logger.WithFields("key1", "val1")); err != nil {
+		t.Fatal(err)
+	}
+
+	l.Error(ctx, "msg1", errors.New("err"))
+
+	if !bytes.Contains(buf.Bytes(), []byte(`timestamp=1970-01-01T03:00:00.000000000+03:00`)) &&
+		!bytes.Contains(buf.Bytes(), []byte(`timestamp=1970-01-01T00:00:00.000000000Z`)) {
+		t.Fatalf("logger error not works, buf contains: %s", buf.Bytes())
+	}
+}
+
+func TestWithFields(t *testing.T) {
+	ctx := context.TODO()
+	buf := bytes.NewBuffer(nil)
+	l := NewLogger(logger.WithLevel(logger.InfoLevel), logger.WithOutput(buf),
+		WithHandlerFunc(slog.NewTextHandler),
+		logger.WithDedupKeys(true),
+	)
+	if err := l.Init(logger.WithFields("key1", "val1")); err != nil {
+		t.Fatal(err)
+	}
+
+	l.Info(ctx, "msg1")
+
+	l = l.Fields("key1", "val2")
+
+	l.Info(ctx, "msg2")
+
+	if !bytes.Contains(buf.Bytes(), []byte(`msg=msg2 key1=val1`)) {
+		t.Fatalf("logger error not works, buf contains: %s", buf.Bytes())
+	}
+}
+
+func TestWithDedupKeysWithAddFields(t *testing.T) {
+	ctx := context.TODO()
+	buf := bytes.NewBuffer(nil)
+	l := NewLogger(logger.WithLevel(logger.InfoLevel), logger.WithOutput(buf),
+		WithHandlerFunc(slog.NewTextHandler),
+		logger.WithDedupKeys(true),
+	)
+	if err := l.Init(logger.WithFields("key1", "val1")); err != nil {
+		t.Fatal(err)
+	}
+
+	l.Info(ctx, "msg1")
+
+	if err := l.Init(logger.WithAddFields("key2", "val2")); err != nil {
+		t.Fatal(err)
+	}
+
+	l.Info(ctx, "msg2")
+
+	if err := l.Init(logger.WithAddFields("key2", "val3", "key1", "val4")); err != nil {
+		t.Fatal(err)
+	}
+
+	l.Info(ctx, "msg3")
+
+	if !bytes.Contains(buf.Bytes(), []byte(`msg=msg3 key1=val4 key2=val3`)) {
+		t.Fatalf("logger error not works, buf contains: %s", buf.Bytes())
+	}
+}
+
+func TestWithHandlerFunc(t *testing.T) {
+	ctx := context.TODO()
+	buf := bytes.NewBuffer(nil)
+	l := NewLogger(logger.WithLevel(logger.InfoLevel), logger.WithOutput(buf),
+		WithHandlerFunc(slog.NewTextHandler),
+	)
+	if err := l.Init(); err != nil {
+		t.Fatal(err)
+	}
+
+	l.Info(ctx, "msg1")
+
+	if !bytes.Contains(buf.Bytes(), []byte(`msg=msg1`)) {
+		t.Fatalf("logger error not works, buf contains: %s", buf.Bytes())
+	}
+}
+
+func TestWithAddFields(t *testing.T) {
+	ctx := context.TODO()
+	buf := bytes.NewBuffer(nil)
+	l := NewLogger(logger.WithLevel(logger.InfoLevel), logger.WithOutput(buf))
+	if err := l.Init(); err != nil {
+		t.Fatal(err)
+	}
+
+	l.Info(ctx, "msg1")
+
+	if err := l.Init(logger.WithAddFields("key1", "val1")); err != nil {
+		t.Fatal(err)
+	}
+	l.Info(ctx, "msg2")
+
+	if err := l.Init(logger.WithAddFields("key2", "val2")); err != nil {
+		t.Fatal(err)
+	}
+	l.Info(ctx, "msg3")
+
+	if !bytes.Contains(buf.Bytes(), []byte(`"key1"`)) {
+		t.Fatalf("logger error not works, buf contains: %s", buf.Bytes())
+	}
+	if !bytes.Contains(buf.Bytes(), []byte(`"key2"`)) {
+		t.Fatalf("logger error not works, buf contains: %s", buf.Bytes())
+	}
+}
+
+func TestMultipleFieldsWithLevel(t *testing.T) {
+	ctx := context.TODO()
+	buf := bytes.NewBuffer(nil)
+	l := NewLogger(logger.WithLevel(logger.InfoLevel), logger.WithOutput(buf))
+	if err := l.Init(); err != nil {
+		t.Fatal(err)
+	}
+
+	l = l.Fields("key", "val")
+
+	l.Info(ctx, "msg1")
+	nl := l.Clone(logger.WithLevel(logger.DebugLevel))
+	nl.Debug(ctx, "msg2")
+	l.Debug(ctx, "msg3")
+	if !bytes.Contains(buf.Bytes(), []byte(`"key":"val"`)) {
+		t.Fatalf("logger error not works, buf contains: %s", buf.Bytes())
+	}
+	if !bytes.Contains(buf.Bytes(), []byte(`"msg1"`)) {
+		t.Fatalf("logger error not works, buf contains: %s", buf.Bytes())
+	}
+	if !bytes.Contains(buf.Bytes(), []byte(`"msg2"`)) {
+		t.Fatalf("logger error not works, buf contains: %s", buf.Bytes())
+	}
+	if bytes.Contains(buf.Bytes(), []byte(`"msg3"`)) {
+		t.Fatalf("logger error not works, buf contains: %s", buf.Bytes())
+	}
+}
+
+func TestMultipleFields(t *testing.T) {
+	ctx := context.TODO()
+	buf := bytes.NewBuffer(nil)
+	l := NewLogger(logger.WithLevel(logger.InfoLevel), logger.WithOutput(buf))
+	if err := l.Init(); err != nil {
+		t.Fatal(err)
+	}
+
+	l = l.Fields("key", "val")
+
+	l = l.Fields("key1", "val1")
+
+	l.Info(ctx, "msg")
+
+	if !bytes.Contains(buf.Bytes(), []byte(`"key":"val"`)) {
+		t.Fatalf("logger error not works, buf contains: %s", buf.Bytes())
+	}
+	if !bytes.Contains(buf.Bytes(), []byte(`"key1":"val1"`)) {
+		t.Fatalf("logger error not works, buf contains: %s", buf.Bytes())
+	}
+}
+
+func TestError(t *testing.T) {
+	ctx := context.TODO()
+	buf := bytes.NewBuffer(nil)
+	l := NewLogger(logger.WithLevel(logger.ErrorLevel), logger.WithOutput(buf), logger.WithAddStacktrace(true))
+	if err := l.Init(); err != nil {
+		t.Fatal(err)
+	}
+
+	l.Error(ctx, "message", fmt.Errorf("error message"))
+	if !bytes.Contains(buf.Bytes(), []byte(`"stacktrace":"`)) {
+		t.Fatalf("logger stacktrace not works, buf contains: %s", buf.Bytes())
+	}
+	if !bytes.Contains(buf.Bytes(), []byte(`"error":"`)) {
+		t.Fatalf("logger error not works, buf contains: %s", buf.Bytes())
+	}
+}
+
+func TestErrorf(t *testing.T) {
+	ctx := context.TODO()
+
+	buf := bytes.NewBuffer(nil)
+	l := NewLogger(logger.WithLevel(logger.ErrorLevel), logger.WithOutput(buf), logger.WithAddStacktrace(true))
+	if err := l.Init(logger.WithContextAttrFuncs(func(_ context.Context) []interface{} {
+		return nil
+	})); err != nil {
+		t.Fatal(err)
+	}
+
+	l.Log(ctx, logger.ErrorLevel, "message", errors.New("error msg"))
+
+	l.Log(ctx, logger.ErrorLevel, "", errors.New("error msg"))
+	if !bytes.Contains(buf.Bytes(), []byte(`"error":"error msg"`)) {
+		t.Fatalf("logger error not works, buf contains: %s", buf.Bytes())
+	}
+
+	if !bytes.Contains(buf.Bytes(), []byte(`"stacktrace":"`)) {
+		t.Fatalf("logger stacktrace not works, buf contains: %s", buf.Bytes())
+	}
+	if !bytes.Contains(buf.Bytes(), []byte(`"error":"`)) {
+		t.Fatalf("logger error not works, buf contains: %s", buf.Bytes())
+	}
+}
+
+func TestContext(t *testing.T) {
+	ctx := context.TODO()
+	buf := bytes.NewBuffer(nil)
+	l := NewLogger(logger.WithLevel(logger.TraceLevel), logger.WithOutput(buf))
+	if err := l.Init(); err != nil {
+		t.Fatal(err)
+	}
+
+	nl, ok := logger.FromContext(logger.NewContext(ctx, l.Fields("key", "val")))
+	if !ok {
+		t.Fatal("context without logger")
+	}
+	nl.Info(ctx, "message")
+	if !bytes.Contains(buf.Bytes(), []byte(`"key":"val"`)) {
+		t.Fatalf("logger fields not works, buf contains: %s", buf.Bytes())
+	}
+}
+
+func TestFields(t *testing.T) {
+	ctx := context.TODO()
+	buf := bytes.NewBuffer(nil)
+	l := NewLogger(logger.WithLevel(logger.TraceLevel), logger.WithOutput(buf))
+	if err := l.Init(); err != nil {
+		t.Fatal(err)
+	}
+
+	nl := l.Fields("key", "val")
+
+	nl.Info(ctx, "message")
+	if !bytes.Contains(buf.Bytes(), []byte(`"key":"val"`)) {
+		t.Fatalf("logger fields not works, buf contains: %s", buf.Bytes())
+	}
+}
+
+func TestFromContextWithFields(t *testing.T) {
+	ctx := context.TODO()
+	buf := bytes.NewBuffer(nil)
+	var ok bool
+	l := NewLogger(logger.WithLevel(logger.TraceLevel), logger.WithOutput(buf))
+	if err := l.Init(); err != nil {
+		t.Fatal(err)
+	}
+	nl := l.Fields("key", "val")
+
+	ctx = logger.NewContext(ctx, nl)
+
+	l, ok = logger.FromContext(ctx)
+	if !ok {
+		t.Fatalf("context does not have logger")
+	}
+
+	l.Info(ctx, "message")
+	if !bytes.Contains(buf.Bytes(), []byte(`"key":"val"`)) {
+		t.Fatalf("logger fields not works, buf contains: %s", buf.Bytes())
+	}
+
+	l.Info(ctx, "test", "uncorrected number attributes")
+	if !bytes.Contains(buf.Bytes(), []byte(`"!BADKEY":"uncorrected number attributes"`)) {
+		t.Fatalf("logger fields not works, buf contains: %s", buf.Bytes())
+	}
+}
+
+func TestClone(t *testing.T) {
+	ctx := context.TODO()
+	buf := bytes.NewBuffer(nil)
+	l := NewLogger(logger.WithLevel(logger.TraceLevel), logger.WithOutput(buf))
+	if err := l.Init(); err != nil {
+		t.Fatal(err)
+	}
+	nl := l.Clone(logger.WithLevel(logger.ErrorLevel))
+	if err := nl.Init(); err != nil {
+		t.Fatal(err)
+	}
+	nl.Info(ctx, "info message")
+	if len(buf.Bytes()) != 0 {
+		t.Fatal("message must not be logged")
+	}
+	l.Info(ctx, "info message")
+	if len(buf.Bytes()) == 0 {
+		t.Fatal("message must be logged")
+	}
+}
+
+func TestRedirectStdLogger(t *testing.T) {
+	buf := bytes.NewBuffer(nil)
+	l := NewLogger(logger.WithLevel(logger.ErrorLevel), logger.WithOutput(buf))
+	if err := l.Init(); err != nil {
+		t.Fatal(err)
+	}
+	fn := logger.RedirectStdLogger(l, logger.ErrorLevel)
+	defer fn()
+	log.Print("test")
+	if !(bytes.Contains(buf.Bytes(), []byte(`"level":"error"`)) && bytes.Contains(buf.Bytes(), []byte(`"msg":"test"`))) {
+		t.Fatalf("logger error, buf %s", buf.Bytes())
+	}
+}
+
+func TestStdLogger(t *testing.T) {
+	buf := bytes.NewBuffer(nil)
+	l := NewLogger(logger.WithLevel(logger.TraceLevel), logger.WithOutput(buf))
+	if err := l.Init(); err != nil {
+		t.Fatal(err)
+	}
+	lg := logger.NewStdLogger(l, logger.ErrorLevel)
+	lg.Print("test")
+	if !(bytes.Contains(buf.Bytes(), []byte(`"level":"error"`)) && bytes.Contains(buf.Bytes(), []byte(`"msg":"test"`))) {
+		t.Fatalf("logger error, buf %s", buf.Bytes())
+	}
+}
+
+func TestLogger(t *testing.T) {
+	ctx := context.TODO()
+	buf := bytes.NewBuffer(nil)
+	l := NewLogger(logger.WithLevel(logger.TraceLevel), logger.WithOutput(buf))
+	if err := l.Init(); err != nil {
+		t.Fatal(err)
+	}
+	l.Trace(ctx, "trace_msg1")
+	l.Warn(ctx, "warn_msg1")
+	l.Fields("error", "test").Info(ctx, "error message")
+	l.Warn(ctx, "first second")
+
+	if !(bytes.Contains(buf.Bytes(), []byte(`"level":"trace"`)) && bytes.Contains(buf.Bytes(), []byte(`"msg":"trace_msg1"`))) {
+		t.Fatalf("logger tracer, buf %s", buf.Bytes())
+	}
+	if !(bytes.Contains(buf.Bytes(), []byte(`"level":"warn"`)) && bytes.Contains(buf.Bytes(), []byte(`"msg":"warn_msg1"`))) {
+		t.Fatalf("logger warn, buf %s", buf.Bytes())
+	}
+	if !(bytes.Contains(buf.Bytes(), []byte(`"level":"info"`)) && bytes.Contains(buf.Bytes(), []byte(`"msg":"error message","error":"test"`))) {
+		t.Fatalf("logger info, buf %s", buf.Bytes())
+	}
+	if !(bytes.Contains(buf.Bytes(), []byte(`"level":"warn"`)) && bytes.Contains(buf.Bytes(), []byte(`"msg":"first second"`))) {
+		t.Fatalf("logger warn, buf %s", buf.Bytes())
+	}
+}
+
+func Test_WithContextAttrFunc(t *testing.T) {
+	loggerContextAttrFuncs := []logger.ContextAttrFunc{
+		func(ctx context.Context) []interface{} {
+			md, ok := metadata.FromIncomingContext(ctx)
+			if !ok {
+				return nil
+			}
+			attrs := make([]interface{}, 0, 10)
+			for k, v := range md {
+				key := strings.ToLower(k)
+				switch key {
+				case "x-request-id", "phone", "external-Id", "source-service", "x-app-install-id", "client-id", "client-ip":
+					attrs = append(attrs, key, v[0])
+				}
+			}
+			return attrs
+		},
+	}
+
+	logger.DefaultContextAttrFuncs = append(logger.DefaultContextAttrFuncs, loggerContextAttrFuncs...)
+
+	ctx := context.TODO()
+	ctx = metadata.AppendIncomingContext(ctx, "X-Request-Id", uuid.New().String(),
+		"Source-Service", "Test-System")
+
+	buf := bytes.NewBuffer(nil)
+	l := NewLogger(logger.WithLevel(logger.TraceLevel), logger.WithOutput(buf))
+	if err := l.Init(); err != nil {
+		t.Fatal(err)
+	}
+
+	l.Info(ctx, "test message")
+	if !(bytes.Contains(buf.Bytes(), []byte(`"level":"info"`)) && bytes.Contains(buf.Bytes(), []byte(`"msg":"test message"`))) {
+		t.Fatalf("logger info, buf %s", buf.Bytes())
+	}
+	if !(bytes.Contains(buf.Bytes(), []byte(`"x-request-id":"`))) {
+		t.Fatalf("logger info, buf %s", buf.Bytes())
+	}
+	if !(bytes.Contains(buf.Bytes(), []byte(`"source-service":"Test-System"`))) {
+		t.Fatalf("logger info, buf %s", buf.Bytes())
+	}
+	buf.Reset()
+	imd, _ := metadata.FromIncomingContext(ctx)
+	l.Info(ctx, "test message1")
+	imd.Set("Source-Service", "Test-System2")
+	l.Info(ctx, "test message2")
+
+	// t.Logf("xxx %s", buf.Bytes())
+}

logger/unwrap/unwrap.go

@@ -36,8 +36,8 @@ var (
 	circularShortBytes = []byte("<shown>")
 	invalidAngleBytes  = []byte("<invalid>")
 	filteredBytes      = []byte("<filtered>")
-	openBracketBytes   = []byte("[")
+	// openBracketBytes   = []byte("[")
-	closeBracketBytes  = []byte("]")
+	// closeBracketBytes  = []byte("]")
 	percentBytes    = []byte("%")
 	precisionBytes  = []byte(".")
 	openAngleBytes  = []byte("<")
@@ -52,13 +52,15 @@ type protoMessage interface {
 }
 
 type Wrapper struct {
+	pointers map[uintptr]int
+	takeMap  map[int]bool
+
 	val  interface{}
 	s    fmt.State
-	pointers         map[uintptr]int
 	opts *Options
+
 	depth            int
 	ignoreNextType   bool
-	takeMap          map[int]bool
 	protoWrapperType bool
 	sqlWrapperType   bool
 }

logger/unwrap/unwrap_test.go

@@ -82,11 +82,11 @@ func TestTagged(t *testing.T) {
 func TestTaggedNested(t *testing.T) {
 	type val struct {
 		key string `logger:"take"`
-		val string `logger:"omit"`
+		// val string `logger:"omit"`
 		unk string
 	}
 	type str struct {
-		key string `logger:"omit"`
+		// key string `logger:"omit"`
 		val *val `logger:"take"`
 	}
 

logger/wrapper/wrapper.go

@@ -1,297 +0,0 @@
-// Package wrapper provides wrapper for Logger
-package wrapper
-
-import (
-	"context"
-	"fmt"
-
-	"go.unistack.org/micro/v4/client"
-	"go.unistack.org/micro/v4/logger"
-	"go.unistack.org/micro/v4/server"
-)
-
-var (
-	// DefaultClientCallObserver called by wrapper in client Call
-	DefaultClientCallObserver = func(ctx context.Context, req client.Request, rsp interface{}, opts []client.CallOption, err error) []string {
-		labels := []string{"service", req.Service(), "endpoint", req.Endpoint()}
-		if err != nil {
-			labels = append(labels, "error", err.Error())
-		}
-		return labels
-	}
-
-	// DefaultClientStreamObserver called by wrapper in client Stream
-	DefaultClientStreamObserver = func(ctx context.Context, req client.Request, opts []client.CallOption, stream client.Stream, err error) []string {
-		labels := []string{"service", req.Service(), "endpoint", req.Endpoint()}
-		if err != nil {
-			labels = append(labels, "error", err.Error())
-		}
-		return labels
-	}
-
-	// DefaultServerHandlerObserver called by wrapper in server Handler
-	DefaultServerHandlerObserver = func(ctx context.Context, req server.Request, rsp interface{}, err error) []string {
-		labels := []string{"service", req.Service(), "endpoint", req.Endpoint()}
-		if err != nil {
-			labels = append(labels, "error", err.Error())
-		}
-		return labels
-	}
-
-	// DefaultClientCallFuncObserver called by wrapper in client CallFunc
-	DefaultClientCallFuncObserver = func(ctx context.Context, addr string, req client.Request, rsp interface{}, opts client.CallOptions, err error) []string {
-		labels := []string{"service", req.Service(), "endpoint", req.Endpoint()}
-		if err != nil {
-			labels = append(labels, "error", err.Error())
-		}
-		return labels
-	}
-
-	// DefaultSkipEndpoints wrapper not called for this endpoints
-	DefaultSkipEndpoints = []string{"Meter.Metrics", "Health.Live", "Health.Ready", "Health.Version"}
-)
-
-type lWrapper struct {
-	client.Client
-	serverHandler  server.HandlerFunc
-	clientCallFunc client.CallFunc
-	opts           Options
-}
-
-type (
-	// ClientCallObserver func signature
-	ClientCallObserver func(context.Context, client.Request, interface{}, []client.CallOption, error) []string
-	// ClientStreamObserver func signature
-	ClientStreamObserver func(context.Context, client.Request, []client.CallOption, client.Stream, error) []string
-	// ClientCallFuncObserver func signature
-	ClientCallFuncObserver func(context.Context, string, client.Request, interface{}, client.CallOptions, error) []string
-	// ServerHandlerObserver func signature
-	ServerHandlerObserver func(context.Context, server.Request, interface{}, error) []string
-)
-
-// Options struct for wrapper
-type Options struct {
-	// Logger that used for log
-	Logger logger.Logger
-	// ServerHandlerObservers funcs
-	ServerHandlerObservers []ServerHandlerObserver
-	// ClientCallObservers funcs
-	ClientCallObservers []ClientCallObserver
-	// ClientStreamObservers funcs
-	ClientStreamObservers []ClientStreamObserver
-	// ClientCallFuncObservers funcs
-	ClientCallFuncObservers []ClientCallFuncObserver
-	// SkipEndpoints
-	SkipEndpoints []string
-	// Level for logger
-	Level logger.Level
-	// Enabled flag
-	Enabled bool
-}
-
-// Option func signature
-type Option func(*Options)
-
-// NewOptions creates Options from Option slice
-func NewOptions(opts ...Option) Options {
-	options := Options{
-		Logger:                  logger.DefaultLogger,
-		Level:                   logger.TraceLevel,
-		ClientCallObservers:     []ClientCallObserver{DefaultClientCallObserver},
-		ClientStreamObservers:   []ClientStreamObserver{DefaultClientStreamObserver},
-		ClientCallFuncObservers: []ClientCallFuncObserver{DefaultClientCallFuncObserver},
-		ServerHandlerObservers:  []ServerHandlerObserver{DefaultServerHandlerObserver},
-		SkipEndpoints:           DefaultSkipEndpoints,
-	}
-
-	for _, o := range opts {
-		o(&options)
-	}
-
-	return options
-}
-
-// WithEnabled enable/diable flag
-func WithEnabled(b bool) Option {
-	return func(o *Options) {
-		o.Enabled = b
-	}
-}
-
-// WithLevel log level
-func WithLevel(l logger.Level) Option {
-	return func(o *Options) {
-		o.Level = l
-	}
-}
-
-// WithLogger logger
-func WithLogger(l logger.Logger) Option {
-	return func(o *Options) {
-		o.Logger = l
-	}
-}
-
-// WithClientCallObservers funcs
-func WithClientCallObservers(ob ...ClientCallObserver) Option {
-	return func(o *Options) {
-		o.ClientCallObservers = ob
-	}
-}
-
-// WithClientStreamObservers funcs
-func WithClientStreamObservers(ob ...ClientStreamObserver) Option {
-	return func(o *Options) {
-		o.ClientStreamObservers = ob
-	}
-}
-
-// WithClientCallFuncObservers funcs
-func WithClientCallFuncObservers(ob ...ClientCallFuncObserver) Option {
-	return func(o *Options) {
-		o.ClientCallFuncObservers = ob
-	}
-}
-
-// WithServerHandlerObservers funcs
-func WithServerHandlerObservers(ob ...ServerHandlerObserver) Option {
-	return func(o *Options) {
-		o.ServerHandlerObservers = ob
-	}
-}
-
-// SkipEndpoins
-func SkipEndpoints(eps ...string) Option {
-	return func(o *Options) {
-		o.SkipEndpoints = append(o.SkipEndpoints, eps...)
-	}
-}
-
-func (l *lWrapper) Call(ctx context.Context, req client.Request, rsp interface{}, opts ...client.CallOption) error {
-	err := l.Client.Call(ctx, req, rsp, opts...)
-
-	endpoint := fmt.Sprintf("%s.%s", req.Service(), req.Endpoint())
-	for _, ep := range l.opts.SkipEndpoints {
-		if ep == endpoint {
-			return err
-		}
-	}
-
-	if !l.opts.Enabled {
-		return err
-	}
-
-	var labels []string
-	for _, o := range l.opts.ClientCallObservers {
-		labels = append(labels, o(ctx, req, rsp, opts, err)...)
-	}
-	l.opts.Logger.Fields(labels).Log(ctx, l.opts.Level)
-
-	return err
-}
-
-func (l *lWrapper) Stream(ctx context.Context, req client.Request, opts ...client.CallOption) (client.Stream, error) {
-	stream, err := l.Client.Stream(ctx, req, opts...)
-
-	endpoint := fmt.Sprintf("%s.%s", req.Service(), req.Endpoint())
-	for _, ep := range l.opts.SkipEndpoints {
-		if ep == endpoint {
-			return stream, err
-		}
-	}
-
-	if !l.opts.Enabled {
-		return stream, err
-	}
-
-	var labels []string
-	for _, o := range l.opts.ClientStreamObservers {
-		labels = append(labels, o(ctx, req, opts, stream, err)...)
-	}
-	l.opts.Logger.Fields(labels).Log(ctx, l.opts.Level)
-
-	return stream, err
-}
-
-func (l *lWrapper) ServerHandler(ctx context.Context, req server.Request, rsp interface{}) error {
-	err := l.serverHandler(ctx, req, rsp)
-
-	endpoint := req.Endpoint()
-	for _, ep := range l.opts.SkipEndpoints {
-		if ep == endpoint {
-			return err
-		}
-	}
-
-	if !l.opts.Enabled {
-		return err
-	}
-
-	var labels []string
-	for _, o := range l.opts.ServerHandlerObservers {
-		labels = append(labels, o(ctx, req, rsp, err)...)
-	}
-	l.opts.Logger.Fields(labels).Log(ctx, l.opts.Level)
-
-	return err
-}
-
-// NewClientWrapper accepts an open options and returns a Client Wrapper
-func NewClientWrapper(opts ...Option) client.Wrapper {
-	return func(c client.Client) client.Client {
-		options := NewOptions()
-		for _, o := range opts {
-			o(&options)
-		}
-		return &lWrapper{opts: options, Client: c}
-	}
-}
-
-// NewClientCallWrapper accepts an options and returns a Call Wrapper
-func NewClientCallWrapper(opts ...Option) client.CallWrapper {
-	return func(h client.CallFunc) client.CallFunc {
-		options := NewOptions()
-		for _, o := range opts {
-			o(&options)
-		}
-
-		l := &lWrapper{opts: options, clientCallFunc: h}
-		return l.ClientCallFunc
-	}
-}
-
-func (l *lWrapper) ClientCallFunc(ctx context.Context, addr string, req client.Request, rsp interface{}, opts client.CallOptions) error {
-	err := l.clientCallFunc(ctx, addr, req, rsp, opts)
-
-	endpoint := fmt.Sprintf("%s.%s", req.Service(), req.Endpoint())
-	for _, ep := range l.opts.SkipEndpoints {
-		if ep == endpoint {
-			return err
-		}
-	}
-
-	if !l.opts.Enabled {
-		return err
-	}
-
-	var labels []string
-	for _, o := range l.opts.ClientCallFuncObservers {
-		labels = append(labels, o(ctx, addr, req, rsp, opts, err)...)
-	}
-	l.opts.Logger.Fields(labels).Log(ctx, l.opts.Level)
-
-	return err
-}
-
-// NewServerHandlerWrapper accepts an options and returns a Handler Wrapper
-func NewServerHandlerWrapper(opts ...Option) server.HandlerWrapper {
-	return func(h server.HandlerFunc) server.HandlerFunc {
-		options := NewOptions()
-		for _, o := range opts {
-			o(&options)
-		}
-
-		l := &lWrapper{opts: options, serverHandler: h}
-		return l.ServerHandler
-	}
-}

metadata/context.go

@@ -1,142 +0,0 @@
-// Package metadata is a way of defining message headers
-package metadata
-
-import (
-	"context"
-)
-
-type (
-	mdIncomingKey struct{}
-	mdOutgoingKey struct{}
-	mdKey         struct{}
-)
-
-// FromIncomingContext returns metadata from incoming ctx
-// returned metadata shoud not be modified or race condition happens
-func FromIncomingContext(ctx context.Context) (Metadata, bool) {
-	if ctx == nil {
-		return nil, false
-	}
-	md, ok := ctx.Value(mdIncomingKey{}).(*rawMetadata)
-	if !ok || md.md == nil {
-		return nil, false
-	}
-	return md.md, ok
-}
-
-// FromOutgoingContext returns metadata from outgoing ctx
-// returned metadata shoud not be modified or race condition happens
-func FromOutgoingContext(ctx context.Context) (Metadata, bool) {
-	if ctx == nil {
-		return nil, false
-	}
-	md, ok := ctx.Value(mdOutgoingKey{}).(*rawMetadata)
-	if !ok || md.md == nil {
-		return nil, false
-	}
-	return md.md, ok
-}
-
-// FromContext returns metadata from the given context
-// returned metadata shoud not be modified or race condition happens
-func FromContext(ctx context.Context) (Metadata, bool) {
-	if ctx == nil {
-		return nil, false
-	}
-	md, ok := ctx.Value(mdKey{}).(*rawMetadata)
-	if !ok || md.md == nil {
-		return nil, false
-	}
-	return md.md, ok
-}
-
-// NewContext creates a new context with the given metadata
-func NewContext(ctx context.Context, md Metadata) context.Context {
-	if ctx == nil {
-		ctx = context.Background()
-	}
-	ctx = context.WithValue(ctx, mdKey{}, &rawMetadata{md})
-	ctx = context.WithValue(ctx, mdIncomingKey{}, &rawMetadata{})
-	ctx = context.WithValue(ctx, mdOutgoingKey{}, &rawMetadata{})
-	return ctx
-}
-
-// SetOutgoingContext modify outgoing context with given metadata
-func SetOutgoingContext(ctx context.Context, md Metadata) bool {
-	if ctx == nil {
-		return false
-	}
-	if omd, ok := ctx.Value(mdOutgoingKey{}).(*rawMetadata); ok {
-		omd.md = md
-		return true
-	}
-	return false
-}
-
-// SetIncomingContext modify incoming context with given metadata
-func SetIncomingContext(ctx context.Context, md Metadata) bool {
-	if ctx == nil {
-		return false
-	}
-	if omd, ok := ctx.Value(mdIncomingKey{}).(*rawMetadata); ok {
-		omd.md = md
-		return true
-	}
-	return false
-}
-
-// NewIncomingContext creates a new context with incoming metadata attached
-func NewIncomingContext(ctx context.Context, md Metadata) context.Context {
-	if ctx == nil {
-		ctx = context.Background()
-	}
-	ctx = context.WithValue(ctx, mdIncomingKey{}, &rawMetadata{md})
-	if v, ok := ctx.Value(mdOutgoingKey{}).(*rawMetadata); !ok || v == nil {
-		ctx = context.WithValue(ctx, mdOutgoingKey{}, &rawMetadata{})
-	}
-	return ctx
-}
-
-// NewOutgoingContext creates a new context with outcoming metadata attached
-func NewOutgoingContext(ctx context.Context, md Metadata) context.Context {
-	if ctx == nil {
-		ctx = context.Background()
-	}
-	ctx = context.WithValue(ctx, mdOutgoingKey{}, &rawMetadata{md})
-	if v, ok := ctx.Value(mdIncomingKey{}).(*rawMetadata); !ok || v == nil {
-		ctx = context.WithValue(ctx, mdIncomingKey{}, &rawMetadata{})
-	}
-	return ctx
-}
-
-// AppendOutgoingContext apends new md to context
-func AppendOutgoingContext(ctx context.Context, kv ...string) context.Context {
-	md, ok := Pairs(kv...)
-	if !ok {
-		return ctx
-	}
-	omd, ok := FromOutgoingContext(ctx)
-	if !ok {
-		return NewOutgoingContext(ctx, md)
-	}
-	for k, v := range md {
-		omd.Set(k, v)
-	}
-	return NewOutgoingContext(ctx, omd)
-}
-
-// AppendIncomingContext apends new md to context
-func AppendIncomingContext(ctx context.Context, kv ...string) context.Context {
-	md, ok := Pairs(kv...)
-	if !ok {
-		return ctx
-	}
-	omd, ok := FromIncomingContext(ctx)
-	if !ok {
-		return NewIncomingContext(ctx, md)
-	}
-	for k, v := range md {
-		omd.Set(k, v)
-	}
-	return NewIncomingContext(ctx, omd)
-}

metadata/context_test.go

@@ -1,140 +0,0 @@
-package metadata
-
-import (
-	"context"
-	"testing"
-)
-
-func TestFromNilContext(t *testing.T) {
-	// nolint: staticcheck
-	c, ok := FromContext(nil)
-	if ok || c != nil {
-		t.Fatal("FromContext not works")
-	}
-}
-
-func TestNewNilContext(t *testing.T) {
-	// nolint: staticcheck
-	ctx := NewContext(nil, New(0))
-
-	c, ok := FromContext(ctx)
-	if c == nil || !ok {
-		t.Fatal("NewContext not works")
-	}
-}
-
-func TestFromContext(t *testing.T) {
-	ctx := context.WithValue(context.TODO(), mdKey{}, &rawMetadata{New(0)})
-
-	c, ok := FromContext(ctx)
-	if c == nil || !ok {
-		t.Fatal("FromContext not works")
-	}
-}
-
-func TestNewContext(t *testing.T) {
-	ctx := NewContext(context.TODO(), New(0))
-
-	c, ok := FromContext(ctx)
-	if c == nil || !ok {
-		t.Fatal("NewContext not works")
-	}
-}
-
-func TestFromIncomingContext(t *testing.T) {
-	ctx := context.WithValue(context.TODO(), mdIncomingKey{}, &rawMetadata{New(0)})
-
-	c, ok := FromIncomingContext(ctx)
-	if c == nil || !ok {
-		t.Fatal("FromIncomingContext not works")
-	}
-}
-
-func TestFromOutgoingContext(t *testing.T) {
-	ctx := context.WithValue(context.TODO(), mdOutgoingKey{}, &rawMetadata{New(0)})
-
-	c, ok := FromOutgoingContext(ctx)
-	if c == nil || !ok {
-		t.Fatal("FromOutgoingContext not works")
-	}
-}
-
-func TestSetIncomingContext(t *testing.T) {
-	md := New(1)
-	md.Set("key", "val")
-	ctx := context.WithValue(context.TODO(), mdIncomingKey{}, &rawMetadata{})
-	if !SetIncomingContext(ctx, md) {
-		t.Fatal("SetIncomingContext not works")
-	}
-	md, ok := FromIncomingContext(ctx)
-	if md == nil || !ok {
-		t.Fatal("SetIncomingContext not works")
-	} else if v, ok := md.Get("key"); !ok || v != "val" {
-		t.Fatal("SetIncomingContext not works")
-	}
-}
-
-func TestSetOutgoingContext(t *testing.T) {
-	md := New(1)
-	md.Set("key", "val")
-	ctx := context.WithValue(context.TODO(), mdOutgoingKey{}, &rawMetadata{})
-	if !SetOutgoingContext(ctx, md) {
-		t.Fatal("SetOutgoingContext not works")
-	}
-	md, ok := FromOutgoingContext(ctx)
-	if md == nil || !ok {
-		t.Fatal("SetOutgoingContext not works")
-	} else if v, ok := md.Get("key"); !ok || v != "val" {
-		t.Fatal("SetOutgoingContext not works")
-	}
-}
-
-func TestNewIncomingContext(t *testing.T) {
-	md := New(1)
-	md.Set("key", "val")
-	ctx := NewIncomingContext(context.TODO(), md)
-
-	c, ok := FromIncomingContext(ctx)
-	if c == nil || !ok {
-		t.Fatal("NewIncomingContext not works")
-	}
-}
-
-func TestNewOutgoingContext(t *testing.T) {
-	md := New(1)
-	md.Set("key", "val")
-	ctx := NewOutgoingContext(context.TODO(), md)
-
-	c, ok := FromOutgoingContext(ctx)
-	if c == nil || !ok {
-		t.Fatal("NewOutgoingContext not works")
-	}
-}
-
-func TestAppendIncomingContext(t *testing.T) {
-	md := New(1)
-	md.Set("key1", "val1")
-	ctx := AppendIncomingContext(context.TODO(), "key2", "val2")
-
-	nmd, ok := FromIncomingContext(ctx)
-	if nmd == nil || !ok {
-		t.Fatal("AppendIncomingContext not works")
-	}
-	if v, ok := nmd.Get("key2"); !ok || v != "val2" {
-		t.Fatal("AppendIncomingContext not works")
-	}
-}
-
-func TestAppendOutgoingContext(t *testing.T) {
-	md := New(1)
-	md.Set("key1", "val1")
-	ctx := AppendOutgoingContext(context.TODO(), "key2", "val2")
-
-	nmd, ok := FromOutgoingContext(ctx)
-	if nmd == nil || !ok {
-		t.Fatal("AppendOutgoingContext not works")
-	}
-	if v, ok := nmd.Get("key2"); !ok || v != "val2" {
-		t.Fatal("AppendOutgoingContext not works")
-	}
-}

metadata/headers.go

@@ -0,0 +1,19 @@
+// Package metadata is a way of defining message headers
+package metadata
+
+var (
+	// HeaderTopic is the header name that contains topic name
+	HeaderTopic = "Micro-Topic"
+	// HeaderContentType specifies content type of message
+	HeaderContentType = "Content-Type"
+	// HeaderEndpoint specifies endpoint in service
+	HeaderEndpoint = "Micro-Endpoint"
+	// HeaderService specifies service
+	HeaderService = "Micro-Service"
+	// HeaderTimeout specifies timeout of operation
+	HeaderTimeout = "Micro-Timeout"
+	// HeaderAuthorization specifies Authorization header
+	HeaderAuthorization = "Authorization"
+	// HeaderXRequestID specifies request id
+	HeaderXRequestID = "X-Request-Id"
+)

metadata/metadata.go

@@ -1,38 +1,462 @@
-// Package metadata is a way of defining message headers
+package metadata
-package metadata // import "go.unistack.org/micro/v4/metadata"
 
 import (
+	"context"
+	"fmt"
 	"net/textproto"
 	"sort"
+	"strings"
 )
 
-var (
-	// HeaderTopic is the header name that contains topic name
-	HeaderTopic = "Micro-Topic"
-	// HeaderContentType specifies content type of message
-	HeaderContentType = "Content-Type"
-	// HeaderEndpoint specifies endpoint in service
-	HeaderEndpoint = "Micro-Endpoint"
-	// HeaderService specifies service
-	HeaderService = "Micro-Service"
-	// HeaderTimeout specifies timeout of operation
-	HeaderTimeout = "Micro-Timeout"
-	// HeaderAuthorization specifies Authorization header
-	HeaderAuthorization = "Authorization"
-)
-
-// Metadata is our way of representing request headers internally.
-// They're used at the RPC level and translate back and forth
-// from Transport headers.
-type Metadata map[string]string
-
-type rawMetadata struct {
-	md Metadata
-}
-
 // defaultMetadataSize used when need to init new Metadata
 var defaultMetadataSize = 2
 
+// Metadata is a mapping from metadata keys to values. Users should use the following
+// two convenience functions New and Pairs to generate Metadata.
+type Metadata map[string][]string
+
+// New creates an zero Metadata.
+func New(l int) Metadata {
+	if l == 0 {
+		l = defaultMetadataSize
+	}
+	md := make(Metadata, l)
+	return md
+}
+
+// NewWithMetadata creates an Metadata from a given key-value map.
+func NewWithMetadata(m map[string]string) Metadata {
+	md := make(Metadata, len(m))
+	for key, val := range m {
+		md[key] = append(md[key], val)
+	}
+	return md
+}
+
+// Pairs returns an Metadata formed by the mapping of key, value ...
+// Pairs panics if len(kv) is odd.
+func Pairs(kv ...string) Metadata {
+	if len(kv)%2 == 1 {
+		panic(fmt.Sprintf("metadata: Pairs got the odd number of input pairs for metadata: %d", len(kv)))
+	}
+	md := make(Metadata, len(kv)/2)
+	for i := 0; i < len(kv); i += 2 {
+		md[kv[i]] = append(md[kv[i]], kv[i+1])
+	}
+	return md
+}
+
+// Len returns the number of items in Metadata.
+func (md Metadata) Len() int {
+	return len(md)
+}
+
+// Copy returns a copy of Metadata.
+func Copy(src Metadata) Metadata {
+	out := make(Metadata, len(src))
+	for k, v := range src {
+		out[k] = copyOf(v)
+	}
+	return out
+}
+
+// Copy returns a copy of Metadata.
+func (md Metadata) Copy() Metadata {
+	out := make(Metadata, len(md))
+	for k, v := range md {
+		out[k] = copyOf(v)
+	}
+	return out
+}
+
+// AsHTTP1 returns a copy of Metadata
+// with CanonicalMIMEHeaderKey.
+func (md Metadata) AsHTTP1() map[string][]string {
+	out := make(map[string][]string, len(md))
+	for k, v := range md {
+		out[textproto.CanonicalMIMEHeaderKey(k)] = copyOf(v)
+	}
+	return out
+}
+
+// AsHTTP1 returns a copy of Metadata
+// with strings.ToLower.
+func (md Metadata) AsHTTP2() map[string][]string {
+	out := make(map[string][]string, len(md))
+	for k, v := range md {
+		out[strings.ToLower(k)] = copyOf(v)
+	}
+	return out
+}
+
+// CopyTo copies Metadata to out.
+func (md Metadata) CopyTo(out Metadata) {
+	for k, v := range md {
+		out[k] = copyOf(v)
+	}
+}
+
+// Get obtains the values for a given key.
+func (md Metadata) MustGet(k string) []string {
+	v, ok := md.Get(k)
+	if !ok {
+		panic("missing metadata key")
+	}
+	return v
+}
+
+// Get obtains the values for a given key.
+func (md Metadata) Get(k string) ([]string, bool) {
+	v, ok := md[k]
+	if !ok {
+		v, ok = md[strings.ToLower(k)]
+	}
+	if !ok {
+		v, ok = md[textproto.CanonicalMIMEHeaderKey(k)]
+	}
+	return v, ok
+}
+
+// MustGetJoined obtains the values for a given key
+// with joined values with "," symbol
+func (md Metadata) MustGetJoined(k string) string {
+	v, ok := md.GetJoined(k)
+	if !ok {
+		panic("missing metadata key")
+	}
+	return v
+}
+
+// GetJoined obtains the values for a given key
+// with joined values with "," symbol
+func (md Metadata) GetJoined(k string) (string, bool) {
+	v, ok := md.Get(k)
+	if !ok {
+		return "", ok
+	}
+	return strings.Join(v, ","), true
+}
+
+// Set sets the value of a given key with a slice of values.
+func (md Metadata) Add(key string, vals ...string) {
+	if len(vals) == 0 {
+		return
+	}
+	md[key] = vals
+}
+
+// Set sets the value of a given key with a slice of values.
+func (md Metadata) Set(kvs ...string) {
+	if len(kvs)%2 == 1 {
+		panic(fmt.Sprintf("metadata: Set got an odd number of input pairs for metadata: %d", len(kvs)))
+	}
+
+	for i := 0; i < len(kvs); i += 2 {
+		md[kvs[i]] = append(md[kvs[i]], kvs[i+1])
+	}
+}
+
+// Append adds the values to key k, not overwriting what was already stored at
+// that key.
+func (md Metadata) Append(key string, vals ...string) {
+	if len(vals) == 0 {
+		return
+	}
+	md[key] = append(md[key], vals...)
+}
+
+// Del removes the values for a given keys k.
+func (md Metadata) Del(k ...string) {
+	for i := range k {
+		delete(md, k[i])
+		delete(md, strings.ToLower(k[i]))
+		delete(md, textproto.CanonicalMIMEHeaderKey(k[i]))
+	}
+}
+
+// Join joins any number of Metadatas into a single Metadata.
+//
+// The order of values for each key is determined by the order in which the Metadatas
+// containing those values are presented to Join.
+func Join(mds ...Metadata) Metadata {
+	out := Metadata{}
+	for _, Metadata := range mds {
+		for k, v := range Metadata {
+			out[k] = append(out[k], v...)
+		}
+	}
+	return out
+}
+
+type (
+	metadataIncomingKey struct{}
+	metadataOutgoingKey struct{}
+	metadataCurrentKey  struct{}
+)
+
+// NewContext creates a new context with Metadata attached. Metadata must
+// not be modified after calling this function.
+func NewContext(ctx context.Context, md Metadata) context.Context {
+	return context.WithValue(ctx, metadataCurrentKey{}, rawMetadata{md: md})
+}
+
+// NewIncomingContext creates a new context with incoming Metadata attached. Metadata must
+// not be modified after calling this function.
+func NewIncomingContext(ctx context.Context, md Metadata) context.Context {
+	return context.WithValue(ctx, metadataIncomingKey{}, rawMetadata{md: md})
+}
+
+// NewOutgoingContext creates a new context with outgoing Metadata attached. If used
+// in conjunction with AppendOutgoingContext, NewOutgoingContext will
+// overwrite any previously-appended metadata. Metadata must not be modified after
+// calling this function.
+func NewOutgoingContext(ctx context.Context, md Metadata) context.Context {
+	return context.WithValue(ctx, metadataOutgoingKey{}, rawMetadata{md: md})
+}
+
+// AppendContext returns a new context with the provided kv merged
+// with any existing metadata in the context. Please refer to the documentation
+// of Pairs for a description of kv.
+func AppendContext(ctx context.Context, kv ...string) context.Context {
+	if len(kv)%2 == 1 {
+		panic(fmt.Sprintf("metadata: AppendContext got an odd number of input pairs for metadata: %d", len(kv)))
+	}
+	md, _ := ctx.Value(metadataCurrentKey{}).(rawMetadata)
+	added := make([][]string, len(md.added)+1)
+	copy(added, md.added)
+	kvCopy := make([]string, 0, len(kv))
+	for i := 0; i < len(kv); i += 2 {
+		kvCopy = append(kvCopy, strings.ToLower(kv[i]), kv[i+1])
+	}
+	added[len(added)-1] = kvCopy
+	return context.WithValue(ctx, metadataCurrentKey{}, rawMetadata{md: md.md, added: added})
+}
+
+// AppendIncomingContext returns a new context with the provided kv merged
+// with any existing metadata in the context. Please refer to the documentation
+// of Pairs for a description of kv.
+func AppendIncomingContext(ctx context.Context, kv ...string) context.Context {
+	if len(kv)%2 == 1 {
+		panic(fmt.Sprintf("metadata: AppendIncomingContext got an odd number of input pairs for metadata: %d", len(kv)))
+	}
+	md, _ := ctx.Value(metadataIncomingKey{}).(rawMetadata)
+	added := make([][]string, len(md.added)+1)
+	copy(added, md.added)
+	kvCopy := make([]string, 0, len(kv))
+	for i := 0; i < len(kv); i += 2 {
+		kvCopy = append(kvCopy, strings.ToLower(kv[i]), kv[i+1])
+	}
+	added[len(added)-1] = kvCopy
+	return context.WithValue(ctx, metadataIncomingKey{}, rawMetadata{md: md.md, added: added})
+}
+
+// AppendOutgoingContext returns a new context with the provided kv merged
+// with any existing metadata in the context. Please refer to the documentation
+// of Pairs for a description of kv.
+func AppendOutgoingContext(ctx context.Context, kv ...string) context.Context {
+	if len(kv)%2 == 1 {
+		panic(fmt.Sprintf("metadata: AppendOutgoingContext got an odd number of input pairs for metadata: %d", len(kv)))
+	}
+	md, _ := ctx.Value(metadataOutgoingKey{}).(rawMetadata)
+	added := make([][]string, len(md.added)+1)
+	copy(added, md.added)
+	kvCopy := make([]string, 0, len(kv))
+	for i := 0; i < len(kv); i += 2 {
+		kvCopy = append(kvCopy, strings.ToLower(kv[i]), kv[i+1])
+	}
+	added[len(added)-1] = kvCopy
+	return context.WithValue(ctx, metadataOutgoingKey{}, rawMetadata{md: md.md, added: added})
+}
+
+// FromContext returns the metadata in ctx if it exists.
+func FromContext(ctx context.Context) (Metadata, bool) {
+	raw, ok := ctx.Value(metadataCurrentKey{}).(rawMetadata)
+	if !ok {
+		return nil, false
+	}
+	metadataSize := len(raw.md)
+	for i := range raw.added {
+		metadataSize += len(raw.added[i]) / 2
+	}
+
+	out := make(Metadata, metadataSize)
+	for k, v := range raw.md {
+		out[k] = copyOf(v)
+	}
+	for _, added := range raw.added {
+		if len(added)%2 == 1 {
+			panic(fmt.Sprintf("metadata: FromContext got an odd number of input pairs for metadata: %d", len(added)))
+		}
+
+		for i := 0; i < len(added); i += 2 {
+			out[added[i]] = append(out[added[i]], added[i+1])
+		}
+	}
+	return out, true
+}
+
+// MustContext returns the metadata in ctx.
+func MustContext(ctx context.Context) Metadata {
+	md, ok := FromContext(ctx)
+	if !ok {
+		panic("missing metadata")
+	}
+	return md
+}
+
+// FromIncomingContext returns the incoming metadata in ctx if it exists.
+func FromIncomingContext(ctx context.Context) (Metadata, bool) {
+	raw, ok := ctx.Value(metadataIncomingKey{}).(rawMetadata)
+	if !ok {
+		return nil, false
+	}
+	metadataSize := len(raw.md)
+	for i := range raw.added {
+		metadataSize += len(raw.added[i]) / 2
+	}
+
+	out := make(Metadata, metadataSize)
+	for k, v := range raw.md {
+		out[k] = copyOf(v)
+	}
+	for _, added := range raw.added {
+		if len(added)%2 == 1 {
+			panic(fmt.Sprintf("metadata: FromIncomingContext got an odd number of input pairs for metadata: %d", len(added)))
+		}
+
+		for i := 0; i < len(added); i += 2 {
+			out[added[i]] = append(out[added[i]], added[i+1])
+		}
+	}
+	return out, true
+}
+
+// MustIncomingContext returns the incoming metadata in ctx.
+func MustIncomingContext(ctx context.Context) Metadata {
+	md, ok := FromIncomingContext(ctx)
+	if !ok {
+		panic("missing metadata")
+	}
+	return md
+}
+
+// ValueFromIncomingContext returns the metadata value corresponding to the metadata
+// key from the incoming metadata if it exists. Keys are matched in a case insensitive
+// manner.
+func ValueFromIncomingContext(ctx context.Context, key string) []string {
+	raw, ok := ctx.Value(metadataIncomingKey{}).(rawMetadata)
+	if !ok {
+		return nil
+	}
+
+	if v, ok := raw.md[key]; ok {
+		return copyOf(v)
+	}
+	for k, v := range raw.md {
+		// Case insensitive comparison: Metadata is a map, and there's no guarantee
+		// that the Metadata attached to the context is created using our helper
+		// functions.
+		if strings.EqualFold(k, key) {
+			return copyOf(v)
+		}
+	}
+	return nil
+}
+
+// ValueFromCurrentContext returns the metadata value corresponding to the metadata
+// key from the incoming metadata if it exists. Keys are matched in a case insensitive
+// manner.
+func ValueFromCurrentContext(ctx context.Context, key string) []string {
+	md, ok := ctx.Value(metadataCurrentKey{}).(rawMetadata)
+	if !ok {
+		return nil
+	}
+
+	if v, ok := md.md[key]; ok {
+		return copyOf(v)
+	}
+	for k, v := range md.md {
+		// Case insensitive comparison: Metadata is a map, and there's no guarantee
+		// that the Metadata attached to the context is created using our helper
+		// functions.
+		if strings.EqualFold(k, key) {
+			return copyOf(v)
+		}
+	}
+	return nil
+}
+
+// MustOutgoingContext returns the outgoing metadata in ctx.
+func MustOutgoingContext(ctx context.Context) Metadata {
+	md, ok := FromOutgoingContext(ctx)
+	if !ok {
+		panic("missing metadata")
+	}
+	return md
+}
+
+// ValueFromOutgoingContext returns the metadata value corresponding to the metadata
+// key from the incoming metadata if it exists. Keys are matched in a case insensitive
+// manner.
+func ValueFromOutgoingContext(ctx context.Context, key string) []string {
+	md, ok := ctx.Value(metadataOutgoingKey{}).(rawMetadata)
+	if !ok {
+		return nil
+	}
+
+	if v, ok := md.md[key]; ok {
+		return copyOf(v)
+	}
+	for k, v := range md.md {
+		// Case insensitive comparison: Metadata is a map, and there's no guarantee
+		// that the Metadata attached to the context is created using our helper
+		// functions.
+		if strings.EqualFold(k, key) {
+			return copyOf(v)
+		}
+	}
+	return nil
+}
+
+func copyOf(v []string) []string {
+	vals := make([]string, len(v))
+	copy(vals, v)
+	return vals
+}
+
+// FromOutgoingContext returns the outgoing metadata in ctx if it exists.
+func FromOutgoingContext(ctx context.Context) (Metadata, bool) {
+	raw, ok := ctx.Value(metadataOutgoingKey{}).(rawMetadata)
+	if !ok {
+		return nil, false
+	}
+
+	metadataSize := len(raw.md)
+	for i := range raw.added {
+		metadataSize += len(raw.added[i]) / 2
+	}
+
+	out := make(Metadata, metadataSize)
+	for k, v := range raw.md {
+		out[k] = copyOf(v)
+	}
+	for _, added := range raw.added {
+		if len(added)%2 == 1 {
+			panic(fmt.Sprintf("metadata: FromOutgoingContext got an odd number of input pairs for metadata: %d", len(added)))
+		}
+
+		for i := 0; i < len(added); i += 2 {
+			out[added[i]] = append(out[added[i]], added[i+1])
+		}
+	}
+	return out, ok
+}
+
+type rawMetadata struct {
+	md    Metadata
+	added [][]string
+}
+
 // Iterator used to iterate over metadata with order
 type Iterator struct {
 	md   Metadata
@@ -42,14 +466,18 @@ type Iterator struct {
 }
 
 // Next advance iterator to next element
-func (iter *Iterator) Next(k, v *string) bool {
+func (iter *Iterator) Next(k *string, v *[]string) bool {
 	if iter.cur+1 > iter.cnt {
 		return false
 	}
 
+	if k != nil && v != nil {
 		*k = iter.keys[iter.cur]
-	*v = iter.md[*k]
+		vv := iter.md[*k]
+		*v = make([]string, len(vv))
+		copy(*v, vv)
 		iter.cur++
+	}
 	return true
 }
 
@@ -63,79 +491,3 @@ func (md Metadata) Iterator() *Iterator {
 	sort.Strings(iter.keys)
 	return iter
 }
-
-// Get returns value from metadata by key
-func (md Metadata) Get(key string) (string, bool) {
-	// fast path
-	val, ok := md[key]
-	if !ok {
-		// slow path
-		val, ok = md[textproto.CanonicalMIMEHeaderKey(key)]
-	}
-	return val, ok
-}
-
-// Set is used to store value in metadata
-func (md Metadata) Set(kv ...string) {
-	if len(kv)%2 == 1 {
-		kv = kv[:len(kv)-1]
-	}
-	for idx := 0; idx < len(kv); idx += 2 {
-		md[textproto.CanonicalMIMEHeaderKey(kv[idx])] = kv[idx+1]
-	}
-}
-
-// Del is used to remove value from metadata
-func (md Metadata) Del(keys ...string) {
-	for _, key := range keys {
-		// fast path
-		delete(md, key)
-		// slow path
-		delete(md, textproto.CanonicalMIMEHeaderKey(key))
-	}
-}
-
-// Copy makes a copy of the metadata
-func Copy(md Metadata) Metadata {
-	nmd := New(len(md))
-	for key, val := range md {
-		nmd.Set(key, val)
-	}
-	return nmd
-}
-
-// New return new sized metadata
-func New(size int) Metadata {
-	if size == 0 {
-		size = defaultMetadataSize
-	}
-	return make(Metadata, size)
-}
-
-// Merge merges metadata to existing metadata, overwriting if specified
-func Merge(omd Metadata, mmd Metadata, overwrite bool) Metadata {
-	var ok bool
-	nmd := Copy(omd)
-	for key, val := range mmd {
-		_, ok = nmd[key]
-		switch {
-		case ok && !overwrite:
-			continue
-		case val != "":
-			nmd.Set(key, val)
-		case ok && val == "":
-			nmd.Del(key)
-		}
-	}
-	return nmd
-}
-
-// Pairs from which metadata created
-func Pairs(kv ...string) (Metadata, bool) {
-	if len(kv)%2 == 1 {
-		return nil, false
-	}
-	md := New(len(kv) / 2)
-	md.Set(kv...)
-	return md, true
-}

metadata/metadata_test.go

@@ -5,17 +5,56 @@ import (
 	"testing"
 )
 
+/*
+func TestAppendOutgoingContextModify(t *testing.T) {
+	md := Pairs("key1", "val1")
+	ctx := NewOutgoingContext(context.TODO(), md)
+	nctx := AppendOutgoingContext(ctx, "key1", "val3", "key2", "val2")
+	_ = nctx
+	omd := MustOutgoingContext(nctx)
+	fmt.Printf("%#+v\n", omd)
+}
+*/
+
+func TestLowercase(t *testing.T) {
+	md := New(1)
+	md["x-request-id"] = []string{"12345"}
+	v, ok := md.GetJoined("X-Request-Id")
+	if !ok || v == "" {
+		t.Fatalf("metadata invalid %#+v", md)
+	}
+}
+
+func TestMultipleUsage(t *testing.T) {
+	ctx := context.TODO()
+	md := New(0)
+	md.Set("key1_1", "val1_1", "key1_2", "val1_2", "key1_3", "val1_3")
+	ctx = NewIncomingContext(ctx, Copy(md))
+	ctx = NewOutgoingContext(ctx, Copy(md))
+	imd, _ := FromIncomingContext(ctx)
+	omd, _ := FromOutgoingContext(ctx)
+	_ = func(x context.Context) context.Context {
+		m, _ := FromIncomingContext(x)
+		m.Del("key1_2")
+		return ctx
+	}(ctx)
+	_ = func(x context.Context) context.Context {
+		m, _ := FromIncomingContext(x)
+		m.Del("key1_3")
+		return ctx
+	}(ctx)
+	_ = imd
+	_ = omd
+}
+
 func TestMetadataSetMultiple(t *testing.T) {
 	md := New(4)
-	md.Set("key1", "val1", "key2", "val2", "key3")
+	md.Set("key1", "val1", "key2", "val2")
 
-	if v, ok := md.Get("key1"); !ok || v != "val1" {
+	if v, ok := md.GetJoined("key1"); !ok || v != "val1" {
 		t.Fatalf("invalid kv %#+v", md)
 	}
-	if v, ok := md.Get("key2"); !ok || v != "val2" {
+	if v, ok := md.GetJoined("key2"); !ok || v != "val2" {
-		t.Fatalf("invalid kv %#+v", md)
-	}
-	if _, ok := md.Get("key3"); ok {
 		t.Fatalf("invalid kv %#+v", md)
 	}
 }
@@ -33,22 +72,12 @@ func TestAppend(t *testing.T) {
 }
 
 func TestPairs(t *testing.T) {
-	md, ok := Pairs("key1", "val1", "key2", "val2")
+	md := Pairs("key1", "val1", "key2", "val2")
-	if !ok {
+	if _, ok := md.Get("key1"); !ok {
-		t.Fatal("odd number of kv")
-	}
-	if _, ok = md.Get("key1"); !ok {
 		t.Fatal("key1 not found")
 	}
 }
 
-func testCtx(ctx context.Context) {
-	md := New(2)
-	md.Set("Key1", "Val1_new")
-	md.Set("Key3", "Val3")
-	SetOutgoingContext(ctx, md)
-}
-
 func TestPassing(t *testing.T) {
 	ctx := context.TODO()
 	md1 := New(2)
@@ -56,62 +85,62 @@ func TestPassing(t *testing.T) {
 	md1.Set("Key2", "Val2")
 
 	ctx = NewIncomingContext(ctx, md1)
-	testCtx(ctx)
+
+	_, ok := FromOutgoingContext(ctx)
+	if ok {
+		t.Fatalf("create outgoing context")
+	}
+
+	ctx = NewOutgoingContext(ctx, md1)
+
 	md, ok := FromOutgoingContext(ctx)
 	if !ok {
 		t.Fatalf("missing metadata from outgoing context")
 	}
-	if v, ok := md.Get("Key1"); !ok || v != "Val1_new" {
+	if v, ok := md.Get("Key1"); !ok || v[0] != "Val1" {
 		t.Fatalf("invalid metadata value %#+v", md)
 	}
 }
 
-func TestMerge(t *testing.T) {
-	omd := Metadata{
-		"key1": "val1",
-	}
-	mmd := Metadata{
-		"key2": "val2",
-	}
-
-	nmd := Merge(omd, mmd, true)
-	if len(nmd) != 2 {
-		t.Fatalf("merge failed: %v", nmd)
-	}
-}
-
 func TestIterator(t *testing.T) {
-	md := Metadata{
+	md := Pairs(
-		"1Last":   "last",
+		"1Last", "last",
-		"2First":  "first",
+		"2First", "first",
-		"3Second": "second",
+		"3Second", "second",
-	}
+	)
 
 	iter := md.Iterator()
-	var k, v string
+	var k string
-
+	var v []string
+	chk := New(3)
 	for iter.Next(&k, &v) {
-		// fmt.Printf("k: %s, v: %s\n", k, v)
+		chk[k] = v
+	}
+
+	for k, v := range chk {
+		if cv, ok := md[k]; !ok || len(cv) != len(v) || cv[0] != v[0] {
+			t.Fatalf("XXXX %#+v %#+v", chk, md)
+		}
 	}
 }
 
 func TestMedataCanonicalKey(t *testing.T) {
 	md := New(1)
 	md.Set("x-request-id", "12345")
-	v, ok := md.Get("x-request-id")
+	v, ok := md.GetJoined("x-request-id")
 	if !ok {
 		t.Fatalf("failed to get x-request-id")
 	} else if v != "12345" {
 		t.Fatalf("invalid metadata value: %s != %s", "12345", v)
 	}
 
-	v, ok = md.Get("X-Request-Id")
+	v, ok = md.GetJoined("X-Request-Id")
 	if !ok {
 		t.Fatalf("failed to get x-request-id")
 	} else if v != "12345" {
 		t.Fatalf("invalid metadata value: %s != %s", "12345", v)
 	}
-	v, ok = md.Get("X-Request-ID")
+	v, ok = md.GetJoined("X-Request-ID")
 	if !ok {
 		t.Fatalf("failed to get x-request-id")
 	} else if v != "12345" {
@@ -124,7 +153,7 @@ func TestMetadataSet(t *testing.T) {
 
 	md.Set("Key", "val")
 
-	val, ok := md.Get("Key")
+	val, ok := md.GetJoined("Key")
 	if !ok {
 		t.Fatal("key Key not found")
 	}
@@ -135,8 +164,8 @@ func TestMetadataSet(t *testing.T) {
 
 func TestMetadataDelete(t *testing.T) {
 	md := Metadata{
-		"Foo": "bar",
+		"Foo": []string{"bar"},
-		"Baz": "empty",
+		"Baz": []string{"empty"},
 	}
 
 	md.Del("Baz")
@@ -146,25 +175,16 @@ func TestMetadataDelete(t *testing.T) {
 	}
 }
 
-func TestNilContext(t *testing.T) {
-	var ctx context.Context
-
-	_, ok := FromContext(ctx)
-	if ok {
-		t.Fatal("nil context")
-	}
-}
-
 func TestMetadataCopy(t *testing.T) {
 	md := Metadata{
-		"Foo": "bar",
+		"Foo": []string{"bar"},
-		"Bar": "baz",
+		"Bar": []string{"baz"},
 	}
 
 	cp := Copy(md)
 
 	for k, v := range md {
-		if cv := cp[k]; cv != v {
+		if cv := cp[k]; cv[0] != v[0] {
 			t.Fatalf("Got %s:%s for %s:%s", k, cv, k, v)
 		}
 	}
@@ -172,7 +192,7 @@ func TestMetadataCopy(t *testing.T) {
 
 func TestMetadataContext(t *testing.T) {
 	md := Metadata{
-		"Foo": "bar",
+		"Foo": []string{"bar"},
 	}
 
 	ctx := NewContext(context.TODO(), md)
@@ -182,7 +202,7 @@ func TestMetadataContext(t *testing.T) {
 		t.Errorf("Unexpected error retrieving metadata, got %t", ok)
 	}
 
-	if emd["Foo"] != md["Foo"] {
+	if emd["Foo"][0] != md["Foo"][0] {
 		t.Errorf("Expected key: %s val: %s, got key: %s val: %s", "Foo", md["Foo"], "Foo", emd["Foo"])
 	}
 
@@ -190,3 +210,89 @@ func TestMetadataContext(t *testing.T) {
 		t.Errorf("Expected metadata length 1 got %d", i)
 	}
 }
+
+func TestFromContext(t *testing.T) {
+	ctx := context.WithValue(context.TODO(), metadataCurrentKey{}, rawMetadata{md: New(0)})
+
+	c, ok := FromContext(ctx)
+	if c == nil || !ok {
+		t.Fatal("FromContext not works")
+	}
+}
+
+func TestNewContext(t *testing.T) {
+	ctx := NewContext(context.TODO(), New(0))
+
+	c, ok := FromContext(ctx)
+	if c == nil || !ok {
+		t.Fatal("NewContext not works")
+	}
+}
+
+func TestFromIncomingContext(t *testing.T) {
+	ctx := context.WithValue(context.TODO(), metadataIncomingKey{}, rawMetadata{md: New(0)})
+
+	c, ok := FromIncomingContext(ctx)
+	if c == nil || !ok {
+		t.Fatal("FromIncomingContext not works")
+	}
+}
+
+func TestFromOutgoingContext(t *testing.T) {
+	ctx := context.WithValue(context.TODO(), metadataOutgoingKey{}, rawMetadata{md: New(0)})
+
+	c, ok := FromOutgoingContext(ctx)
+	if c == nil || !ok {
+		t.Fatal("FromOutgoingContext not works")
+	}
+}
+
+func TestNewIncomingContext(t *testing.T) {
+	md := New(1)
+	md.Set("key", "val")
+	ctx := NewIncomingContext(context.TODO(), md)
+
+	c, ok := FromIncomingContext(ctx)
+	if c == nil || !ok {
+		t.Fatal("NewIncomingContext not works")
+	}
+}
+
+func TestNewOutgoingContext(t *testing.T) {
+	md := New(1)
+	md.Set("key", "val")
+	ctx := NewOutgoingContext(context.TODO(), md)
+
+	c, ok := FromOutgoingContext(ctx)
+	if c == nil || !ok {
+		t.Fatal("NewOutgoingContext not works")
+	}
+}
+
+func TestAppendIncomingContext(t *testing.T) {
+	md := New(1)
+	md.Set("key1", "val1")
+	ctx := AppendIncomingContext(context.TODO(), "key2", "val2")
+
+	nmd, ok := FromIncomingContext(ctx)
+	if nmd == nil || !ok {
+		t.Fatal("AppendIncomingContext not works")
+	}
+	if v, ok := nmd.GetJoined("key2"); !ok || v != "val2" {
+		t.Fatal("AppendIncomingContext not works")
+	}
+}
+
+func TestAppendOutgoingContext(t *testing.T) {
+	md := New(1)
+	md.Set("key1", "val1")
+	ctx := AppendOutgoingContext(context.TODO(), "key2", "val2")
+
+	nmd, ok := FromOutgoingContext(ctx)
+	if nmd == nil || !ok {
+		t.Fatal("AppendOutgoingContext not works")
+	}
+	if v, ok := nmd.GetJoined("key2"); !ok || v != "val2" {
+		t.Fatal("AppendOutgoingContext not works")
+	}
+}

meter/context.go

@@ -15,6 +15,15 @@ func FromContext(ctx context.Context) (Meter, bool) {
 	return c, ok
 }
 
+// MustContext get meter from context
+func MustContext(ctx context.Context) Meter {
+	m, ok := FromContext(ctx)
+	if !ok {
+		panic("missing meter")
+	}
+	return m
+}
+
 // NewContext put meter in context
 func NewContext(ctx context.Context, c Meter) context.Context {
 	if ctx == nil {
@@ -22,3 +31,13 @@ func NewContext(ctx context.Context, c Meter) context.Context {
 	}
 	return context.WithValue(ctx, meterKey{}, c)
 }
+
+// SetOption returns a function to setup a context with given value
+func SetOption(k, v interface{}) Option {
+	return func(o *Options) {
+		if o.Context == nil {
+			o.Context = context.Background()
+		}
+		o.Context = context.WithValue(o.Context, k, v)
+	}
+}

meter/context_test.go

@@ -40,3 +40,14 @@ func TestNewContext(t *testing.T) {
 		t.Fatal("NewContext not works")
 	}
 }
+
+func TestSetOption(t *testing.T) {
+	type key struct{}
+	o := SetOption(key{}, "test")
+	opts := &Options{}
+	o(opts)
+
+	if v, ok := opts.Context.Value(key{}).(string); !ok || v == "" {
+		t.Fatal("SetOption not works")
+	}
+}

meter/meter.go

@@ -1,5 +1,5 @@
 // Package meter is for instrumentation
-package meter // import "go.unistack.org/micro/v4/meter"
+package meter
 
 import (
 	"io"
@@ -7,8 +7,6 @@ import (
 	"strconv"
 	"strings"
 	"time"
-
-	"go.unistack.org/micro/v4/options"
 )
 
 var (
@@ -18,14 +16,19 @@ var (
 	DefaultAddress = ":9090"
 	// DefaultPath the meter endpoint where the Meter data will be made available
 	DefaultPath = "/metrics"
-	// DefaultMetricPrefix holds the string that prepends to all metrics
+	// DefaultMeterStatsInterval specifies interval for meter updating
-	DefaultMetricPrefix = "micro_"
+	DefaultMeterStatsInterval = 5 * time.Second
-	// DefaultLabelPrefix holds the string that prepends to all labels
-	DefaultLabelPrefix = "micro_"
 	// DefaultSummaryQuantiles is the default spread of stats for summary
 	DefaultSummaryQuantiles = []float64{0.5, 0.9, 0.97, 0.99, 1}
 	// DefaultSummaryWindow is the default window for summary
 	DefaultSummaryWindow = 5 * time.Minute
+	// DefaultSkipEndpoints is the slice of endpoint that must not be metered
+	DefaultSkipEndpoints = []string{
+		"MeterService.Metrics",
+		"HealthService.Live",
+		"HealthService.Ready",
+		"HealthService.Version",
+	}
 )
 
 // Meter is an interface for collecting and instrumenting metrics
@@ -33,9 +36,9 @@ type Meter interface {
 	// Name returns meter name
 	Name() string
 	// Init initialize meter
-	Init(opts ...options.Option) error
+	Init(opts ...Option) error
 	// Clone create meter copy with new options
-	Clone(opts ...options.Option) Meter
+	Clone(opts ...Option) Meter
 	// Counter get or create counter
 	Counter(name string, labels ...string) Counter
 	// FloatCounter get or create float counter
@@ -43,7 +46,7 @@ type Meter interface {
 	// Gauge get or create gauge
 	Gauge(name string, fn func() float64, labels ...string) Gauge
 	// Set create new meter metrics set
-	Set(opts ...options.Option) Meter
+	Set(opts ...Option) Meter
 	// Histogram get or create histogram
 	Histogram(name string, labels ...string) Histogram
 	// Summary get or create summary
@@ -51,7 +54,7 @@ type Meter interface {
 	// SummaryExt get or create summary with spcified quantiles and window time
 	SummaryExt(name string, window time.Duration, quantiles []float64, labels ...string) Summary
 	// Write writes metrics to io.Writer
-	Write(w io.Writer, opts ...options.Option) error
+	Write(w io.Writer, opts ...Option) error
 	// Options returns meter options
 	Options() Options
 	// String return meter type

meter/noop.go

@@ -3,8 +3,6 @@ package meter
 import (
 	"io"
 	"time"
-
-	"go.unistack.org/micro/v4/options"
 )
 
 // NoopMeter is an noop implementation of Meter
@@ -13,12 +11,12 @@ type noopMeter struct {
 }
 
 // NewMeter returns a configured noop reporter:
-func NewMeter(opts ...options.Option) Meter {
+func NewMeter(opts ...Option) Meter {
 	return &noopMeter{opts: NewOptions(opts...)}
 }
 
 // Clone return old meter with new options
-func (r *noopMeter) Clone(opts ...options.Option) Meter {
+func (r *noopMeter) Clone(opts ...Option) Meter {
 	options := r.opts
 	for _, o := range opts {
 		o(&options)
@@ -31,7 +29,7 @@ func (r *noopMeter) Name() string {
 }
 
 // Init initialize options
-func (r *noopMeter) Init(opts ...options.Option) error {
+func (r *noopMeter) Init(opts ...Option) error {
 	for _, o := range opts {
 		o(&r.opts)
 	}
@@ -39,37 +37,37 @@ func (r *noopMeter) Init(opts ...options.Option) error {
 }
 
 // Counter implements the Meter interface
-func (r *noopMeter) Counter(name string, labels ...string) Counter {
+func (r *noopMeter) Counter(_ string, labels ...string) Counter {
 	return &noopCounter{labels: labels}
 }
 
 // FloatCounter implements the Meter interface
-func (r *noopMeter) FloatCounter(name string, labels ...string) FloatCounter {
+func (r *noopMeter) FloatCounter(_ string, labels ...string) FloatCounter {
 	return &noopFloatCounter{labels: labels}
 }
 
 // Gauge implements the Meter interface
-func (r *noopMeter) Gauge(name string, f func() float64, labels ...string) Gauge {
+func (r *noopMeter) Gauge(_ string, _ func() float64, labels ...string) Gauge {
 	return &noopGauge{labels: labels}
 }
 
 // Summary implements the Meter interface
-func (r *noopMeter) Summary(name string, labels ...string) Summary {
+func (r *noopMeter) Summary(_ string, labels ...string) Summary {
 	return &noopSummary{labels: labels}
 }
 
 // SummaryExt implements the Meter interface
-func (r *noopMeter) SummaryExt(name string, window time.Duration, quantiles []float64, labels ...string) Summary {
+func (r *noopMeter) SummaryExt(_ string, _ time.Duration, _ []float64, labels ...string) Summary {
 	return &noopSummary{labels: labels}
 }
 
 // Histogram implements the Meter interface
-func (r *noopMeter) Histogram(name string, labels ...string) Histogram {
+func (r *noopMeter) Histogram(_ string, labels ...string) Histogram {
 	return &noopHistogram{labels: labels}
 }
 
 // Set implements the Meter interface
-func (r *noopMeter) Set(opts ...options.Option) Meter {
+func (r *noopMeter) Set(opts ...Option) Meter {
 	m := &noopMeter{opts: r.opts}
 
 	for _, o := range opts {
@@ -79,7 +77,7 @@ func (r *noopMeter) Set(opts ...options.Option) Meter {
 	return m
 }
 
-func (r *noopMeter) Write(_ io.Writer, _ ...options.Option) error {
+func (r *noopMeter) Write(_ io.Writer, _ ...Option) error {
 	return nil
 }
 

meter/options.go

@@ -2,17 +2,13 @@ package meter
 
 import (
 	"context"
-	"reflect"
-
-	"go.unistack.org/micro/v4/logger"
-	"go.unistack.org/micro/v4/options"
-	rutil "go.unistack.org/micro/v4/util/reflect"
 )
 
+// Option powers the configuration for metrics implementations:
+type Option func(*Options)
+
 // Options for metrics implementations
 type Options struct {
-	// Logger used for logging
-	Logger logger.Logger
 	// Context holds external options
 	Context context.Context
 	// Name holds the meter name
@@ -21,10 +17,6 @@ type Options struct {
 	Address string
 	// Path holds the path for metrics
 	Path string
-	// MetricPrefix holds the prefix for all metrics
-	MetricPrefix string
-	// LabelPrefix holds the prefix for all labels
-	LabelPrefix string
 	// Labels holds the default labels
 	Labels []string
 	// WriteProcessMetrics flag to write process metrics
@@ -34,14 +26,11 @@ type Options struct {
 }
 
 // NewOptions prepares a set of options:
-func NewOptions(opt ...options.Option) Options {
+func NewOptions(opt ...Option) Options {
 	opts := Options{
 		Address: DefaultAddress,
 		Path:    DefaultPath,
 		Context: context.Background(),
-		Logger:       logger.DefaultLogger,
-		MetricPrefix: DefaultMetricPrefix,
-		LabelPrefix:  DefaultLabelPrefix,
 	}
 
 	for _, o := range opt {
@@ -51,24 +40,24 @@ func NewOptions(opt ...options.Option) Options {
 	return opts
 }
 
-// LabelPrefix sets the labels prefix
+// Context sets the metrics context
-func LabelPrefix(pref string) options.Option {
+func Context(ctx context.Context) Option {
-	return func(src interface{}) error {
+	return func(o *Options) {
-		return options.Set(src, pref, ".LabelPrefix")
+		o.Context = ctx
-	}
-}
-
-// MetricPrefix sets the metric prefix
-func MetricPrefix(pref string) options.Option {
-	return func(src interface{}) error {
-		return options.Set(src, pref, ".MetricPrefix")
 	}
 }
 
 // Path used to serve metrics over HTTP
-func Path(path string) options.Option {
+func Path(value string) Option {
-	return func(src interface{}) error {
+	return func(o *Options) {
-		return options.Set(src, path, ".Path")
+		o.Path = value
+	}
+}
+
+// Address is the listen address to serve metrics
+func Address(value string) Option {
+	return func(o *Options) {
+		o.Address = value
 	}
 }
 
@@ -81,34 +70,30 @@ func TimingObjectives(value map[float64]float64) Option {
 }
 */
 
-// Labels sets the meter labels
+// Labels add the meter labels
-func Labels(ls ...string) options.Option {
+func Labels(ls ...string) Option {
-	return func(src interface{}) error {
+	return func(o *Options) {
-		v, err := options.Get(src, ".Labels")
+		o.Labels = append(o.Labels, ls...)
-		if err != nil {
-			return err
-		} else if rutil.IsZero(v) {
-			v = reflect.MakeSlice(reflect.TypeOf(v), 0, len(ls)).Interface()
 	}
-		cv := reflect.ValueOf(v)
+}
-		for _, l := range ls {
+
-			reflect.Append(cv, reflect.ValueOf(l))
+// Name sets the name
-		}
+func Name(n string) Option {
-		err = options.Set(src, cv, ".Labels")
+	return func(o *Options) {
-		return err
+		o.Name = n
 	}
 }
 
 // WriteProcessMetrics enable process metrics output for write
-func WriteProcessMetrics(b bool) options.Option {
+func WriteProcessMetrics(b bool) Option {
-	return func(src interface{}) error {
+	return func(o *Options) {
-		return options.Set(src, b, ".WriteProcessMetrics")
+		o.WriteProcessMetrics = b
 	}
 }
 
 // WriteFDMetrics enable fd metrics output for write
-func WriteFDMetrics(b bool) options.Option {
+func WriteFDMetrics(b bool) Option {
-	return func(src interface{}) error {
+	return func(o *Options) {
-		return options.Set(src, b, ".WriteFDMetrics")
+		o.WriteFDMetrics = b
 	}
 }

meter/wrapper/wrapper.go

@@ -1,238 +0,0 @@
-package wrapper // import "go.unistack.org/micro/v4/meter/wrapper"
-
-import (
-	"context"
-	"fmt"
-	"time"
-
-	"go.unistack.org/micro/v4/client"
-	"go.unistack.org/micro/v4/meter"
-	"go.unistack.org/micro/v4/semconv"
-	"go.unistack.org/micro/v4/server"
-)
-
-var (
-	labelSuccess  = "success"
-	labelFailure  = "failure"
-	labelStatus   = "status"
-	labelEndpoint = "endpoint"
-
-	// DefaultSkipEndpoints contains list of endpoints that not evaluted by wrapper
-	DefaultSkipEndpoints = []string{"Meter.Metrics", "Health.Live", "Health.Ready", "Health.Version"}
-)
-
-// Options struct
-type Options struct {
-	Meter         meter.Meter
-	lopts         []meter.Option
-	SkipEndpoints []string
-}
-
-// Option func signature
-type Option func(*Options)
-
-// NewOptions creates new Options struct
-func NewOptions(opts ...Option) Options {
-	options := Options{
-		Meter:         meter.DefaultMeter,
-		lopts:         make([]meter.Option, 0, 5),
-		SkipEndpoints: DefaultSkipEndpoints,
-	}
-	for _, o := range opts {
-		o(&options)
-	}
-	return options
-}
-
-// ServiceName passes service name to meter label
-func ServiceName(name string) Option {
-	return func(o *Options) {
-		o.lopts = append(o.lopts, meter.Labels("name", name))
-	}
-}
-
-// ServiceVersion passes service version to meter label
-func ServiceVersion(version string) Option {
-	return func(o *Options) {
-		o.lopts = append(o.lopts, meter.Labels("version", version))
-	}
-}
-
-// ServiceID passes service id to meter label
-func ServiceID(id string) Option {
-	return func(o *Options) {
-		o.lopts = append(o.lopts, meter.Labels("id", id))
-	}
-}
-
-// Meter passes meter
-func Meter(m meter.Meter) Option {
-	return func(o *Options) {
-		o.Meter = m
-	}
-}
-
-// SkipEndoints add endpoint to skip
-func SkipEndoints(eps ...string) Option {
-	return func(o *Options) {
-		o.SkipEndpoints = append(o.SkipEndpoints, eps...)
-	}
-}
-
-type wrapper struct {
-	client.Client
-	callFunc client.CallFunc
-	opts     Options
-}
-
-// NewClientWrapper create new client wrapper
-func NewClientWrapper(opts ...Option) client.Wrapper {
-	return func(c client.Client) client.Client {
-		handler := &wrapper{
-			opts:   NewOptions(opts...),
-			Client: c,
-		}
-		return handler
-	}
-}
-
-// NewCallWrapper create new call wrapper
-func NewCallWrapper(opts ...Option) client.CallWrapper {
-	return func(fn client.CallFunc) client.CallFunc {
-		handler := &wrapper{
-			opts:     NewOptions(opts...),
-			callFunc: fn,
-		}
-		return handler.CallFunc
-	}
-}
-
-func (w *wrapper) CallFunc(ctx context.Context, addr string, req client.Request, rsp interface{}, opts client.CallOptions) error {
-	endpoint := fmt.Sprintf("%s.%s", req.Service(), req.Endpoint())
-	for _, ep := range w.opts.SkipEndpoints {
-		if ep == endpoint {
-			return w.callFunc(ctx, addr, req, rsp, opts)
-		}
-	}
-
-	labels := make([]string, 0, 4)
-	labels = append(labels, labelEndpoint, endpoint)
-
-	w.opts.Meter.Counter(semconv.ClientRequestInflight, labels...).Inc()
-	ts := time.Now()
-	err := w.callFunc(ctx, addr, req, rsp, opts)
-	te := time.Since(ts)
-	w.opts.Meter.Counter(semconv.ClientRequestInflight, labels...).Dec()
-
-	w.opts.Meter.Summary(semconv.ClientRequestLatencyMicroseconds, labels...).Update(te.Seconds())
-	w.opts.Meter.Histogram(semconv.ClientRequestDurationSeconds, labels...).Update(te.Seconds())
-
-	if err == nil {
-		labels = append(labels, labelStatus, labelSuccess)
-	} else {
-		labels = append(labels, labelStatus, labelFailure)
-	}
-	w.opts.Meter.Counter(semconv.ClientRequestTotal, labels...).Inc()
-
-	return err
-}
-
-func (w *wrapper) Call(ctx context.Context, req client.Request, rsp interface{}, opts ...client.CallOption) error {
-	endpoint := fmt.Sprintf("%s.%s", req.Service(), req.Endpoint())
-	for _, ep := range w.opts.SkipEndpoints {
-		if ep == endpoint {
-			return w.Client.Call(ctx, req, rsp, opts...)
-		}
-	}
-
-	labels := make([]string, 0, 4)
-	labels = append(labels, labelEndpoint, endpoint)
-
-	w.opts.Meter.Counter(semconv.ClientRequestInflight, labels...).Inc()
-	ts := time.Now()
-	err := w.Client.Call(ctx, req, rsp, opts...)
-	te := time.Since(ts)
-	w.opts.Meter.Counter(semconv.ClientRequestInflight, labels...).Dec()
-
-	w.opts.Meter.Summary(semconv.ClientRequestLatencyMicroseconds, labels...).Update(te.Seconds())
-	w.opts.Meter.Histogram(semconv.ClientRequestDurationSeconds, labels...).Update(te.Seconds())
-
-	if err == nil {
-		labels = append(labels, labelStatus, labelSuccess)
-	} else {
-		labels = append(labels, labelStatus, labelFailure)
-	}
-	w.opts.Meter.Counter(semconv.ClientRequestTotal, labels...).Inc()
-
-	return err
-}
-
-func (w *wrapper) Stream(ctx context.Context, req client.Request, opts ...client.CallOption) (client.Stream, error) {
-	endpoint := fmt.Sprintf("%s.%s", req.Service(), req.Endpoint())
-	for _, ep := range w.opts.SkipEndpoints {
-		if ep == endpoint {
-			return w.Client.Stream(ctx, req, opts...)
-		}
-	}
-
-	labels := make([]string, 0, 4)
-	labels = append(labels, labelEndpoint, endpoint)
-
-	w.opts.Meter.Counter(semconv.ClientRequestInflight, labels...).Inc()
-	ts := time.Now()
-	stream, err := w.Client.Stream(ctx, req, opts...)
-	te := time.Since(ts)
-	w.opts.Meter.Counter(semconv.ClientRequestInflight, labels...).Dec()
-
-	w.opts.Meter.Summary(semconv.ClientRequestLatencyMicroseconds, labels...).Update(te.Seconds())
-	w.opts.Meter.Histogram(semconv.ClientRequestDurationSeconds, labels...).Update(te.Seconds())
-
-	if err == nil {
-		labels = append(labels, labelStatus, labelSuccess)
-	} else {
-		labels = append(labels, labelStatus, labelFailure)
-	}
-	w.opts.Meter.Counter(semconv.ClientRequestTotal, labels...).Inc()
-
-	return stream, err
-}
-
-// NewServerHandlerWrapper create new server handler wrapper
-func NewServerHandlerWrapper(opts ...Option) server.HandlerWrapper {
-	handler := &wrapper{
-		opts: NewOptions(opts...),
-	}
-	return handler.HandlerFunc
-}
-
-func (w *wrapper) HandlerFunc(fn server.HandlerFunc) server.HandlerFunc {
-	return func(ctx context.Context, req server.Request, rsp interface{}) error {
-		endpoint := req.Service() + "." + req.Endpoint()
-		for _, ep := range w.opts.SkipEndpoints {
-			if ep == endpoint {
-				return fn(ctx, req, rsp)
-			}
-		}
-
-		labels := make([]string, 0, 4)
-		labels = append(labels, labelEndpoint, endpoint)
-
-		w.opts.Meter.Counter(semconv.ServerRequestInflight, labels...).Inc()
-		ts := time.Now()
-		err := fn(ctx, req, rsp)
-		te := time.Since(ts)
-		w.opts.Meter.Counter(semconv.ServerRequestInflight, labels...).Dec()
-
-		w.opts.Meter.Summary(semconv.ServerRequestLatencyMicroseconds, labels...).Update(te.Seconds())
-		w.opts.Meter.Histogram(semconv.ServerRequestDurationSeconds, labels...).Update(te.Seconds())
-
-		if err == nil {
-			labels = append(labels, labelStatus, labelSuccess)
-		} else {
-			labels = append(labels, labelStatus, labelFailure)
-		}
-		w.opts.Meter.Counter(semconv.ServerRequestTotal, labels...).Inc()
-
-		return err
-	}
-}

micro.go

@@ -0,0 +1,98 @@
+package micro
+
+import (
+	"reflect"
+
+	"go.unistack.org/micro/v4/broker"
+	"go.unistack.org/micro/v4/client"
+	"go.unistack.org/micro/v4/codec"
+	"go.unistack.org/micro/v4/flow"
+	"go.unistack.org/micro/v4/fsm"
+	"go.unistack.org/micro/v4/logger"
+	"go.unistack.org/micro/v4/meter"
+	"go.unistack.org/micro/v4/register"
+	"go.unistack.org/micro/v4/resolver"
+	"go.unistack.org/micro/v4/router"
+	"go.unistack.org/micro/v4/selector"
+	"go.unistack.org/micro/v4/server"
+	"go.unistack.org/micro/v4/store"
+	"go.unistack.org/micro/v4/sync"
+	"go.unistack.org/micro/v4/tracer"
+)
+
+func As(b any, target any) bool {
+	if b == nil {
+		return false
+	}
+	if target == nil {
+		return false
+	}
+	val := reflect.ValueOf(target)
+	typ := val.Type()
+	if typ.Kind() != reflect.Ptr || val.IsNil() {
+		return false
+	}
+	targetType := typ.Elem()
+	if targetType.Kind() != reflect.Interface {
+		switch {
+		case targetType.Implements(brokerType):
+			break
+		case targetType.Implements(loggerType):
+			break
+		case targetType.Implements(clientType):
+			break
+		case targetType.Implements(serverType):
+			break
+		case targetType.Implements(codecType):
+			break
+		case targetType.Implements(flowType):
+			break
+		case targetType.Implements(fsmType):
+			break
+		case targetType.Implements(meterType):
+			break
+		case targetType.Implements(registerType):
+			break
+		case targetType.Implements(resolverType):
+			break
+		case targetType.Implements(selectorType):
+			break
+		case targetType.Implements(storeType):
+			break
+		case targetType.Implements(syncType):
+			break
+		case targetType.Implements(serviceType):
+			break
+		case targetType.Implements(routerType):
+			break
+		case targetType.Implements(tracerType):
+			break
+		default:
+			return false
+		}
+	}
+	if reflect.TypeOf(b).AssignableTo(targetType) {
+		val.Elem().Set(reflect.ValueOf(b))
+		return true
+	}
+	return false
+}
+
+var (
+	brokerType   = reflect.TypeOf((*broker.Broker)(nil)).Elem()
+	loggerType   = reflect.TypeOf((*logger.Logger)(nil)).Elem()
+	clientType   = reflect.TypeOf((*client.Client)(nil)).Elem()
+	serverType   = reflect.TypeOf((*server.Server)(nil)).Elem()
+	codecType    = reflect.TypeOf((*codec.Codec)(nil)).Elem()
+	flowType     = reflect.TypeOf((*flow.Flow)(nil)).Elem()
+	fsmType      = reflect.TypeOf((*fsm.FSM)(nil)).Elem()
+	meterType    = reflect.TypeOf((*meter.Meter)(nil)).Elem()
+	registerType = reflect.TypeOf((*register.Register)(nil)).Elem()
+	resolverType = reflect.TypeOf((*resolver.Resolver)(nil)).Elem()
+	routerType   = reflect.TypeOf((*router.Router)(nil)).Elem()
+	selectorType = reflect.TypeOf((*selector.Selector)(nil)).Elem()
+	storeType    = reflect.TypeOf((*store.Store)(nil)).Elem()
+	syncType     = reflect.TypeOf((*sync.Sync)(nil)).Elem()
+	tracerType   = reflect.TypeOf((*tracer.Tracer)(nil)).Elem()
+	serviceType  = reflect.TypeOf((*Service)(nil)).Elem()
+)

micro_test.go

@@ -0,0 +1,120 @@
+package micro
+
+import (
+	"context"
+	"fmt"
+	"reflect"
+	"testing"
+
+	"go.unistack.org/micro/v4/broker"
+	"go.unistack.org/micro/v4/fsm"
+	"go.unistack.org/micro/v4/metadata"
+)
+
+func TestAs(t *testing.T) {
+	var b *bro
+	broTarget := &bro{name: "kafka"}
+	fsmTarget := &fsmT{name: "fsm"}
+
+	testCases := []struct {
+		b      any
+		target any
+		want   any
+
+		match bool
+	}{
+		{
+			b:      broTarget,
+			target: &b,
+			match:  true,
+			want:   broTarget,
+		},
+		{
+			b:      nil,
+			target: &b,
+			match:  false,
+			want:   nil,
+		},
+		{
+			b:      fsmTarget,
+			target: &b,
+			match:  false,
+			want:   nil,
+		},
+	}
+	for i, tc := range testCases {
+		name := fmt.Sprintf("%d:As(Errorf(..., %v), %v)", i, tc.b, tc.target)
+		// Clear the target pointer, in case it was set in a previous test.
+		rtarget := reflect.ValueOf(tc.target)
+		rtarget.Elem().Set(reflect.Zero(reflect.TypeOf(tc.target).Elem()))
+		t.Run(name, func(t *testing.T) {
+			match := As(tc.b, tc.target)
+			if match != tc.match {
+				t.Fatalf("match: got %v; want %v", match, tc.match)
+			}
+			if !match {
+				return
+			}
+			if got := rtarget.Elem().Interface(); got != tc.want {
+				t.Fatalf("got %#v, want %#v", got, tc.want)
+			}
+		})
+	}
+}
+
+var _ broker.Broker = (*bro)(nil)
+
+type bro struct {
+	name string
+}
+
+func (p *bro) Name() string { return p.name }
+
+func (p *bro) Live() bool { return true }
+
+func (p *bro) Ready() bool { return true }
+
+func (p *bro) Health() bool { return true }
+
+func (p *bro) Init(_ ...broker.Option) error { return nil }
+
+// Options returns broker options
+func (p *bro) Options() broker.Options { return broker.Options{} }
+
+// Address return configured address
+func (p *bro) Address() string { return "" }
+
+// Connect connects to broker
+func (p *bro) Connect(_ context.Context) error { return nil }
+
+// Disconnect disconnect from broker
+func (p *bro) Disconnect(_ context.Context) error { return nil }
+
+// NewMessage creates new message
+func (p *bro) NewMessage(_ context.Context, _ metadata.Metadata, _ interface{}, _ ...broker.PublishOption) (broker.Message, error) {
+	return nil, nil
+}
+
+// Publish message, msg can be single broker.Message or []broker.Message
+func (p *bro) Publish(_ context.Context, _ string, _ ...broker.Message) error {
+	return nil
+}
+
+// Subscribe subscribes to topic message via handler
+func (p *bro) Subscribe(_ context.Context, _ string, _ interface{}, _ ...broker.SubscribeOption) (broker.Subscriber, error) {
+	return nil, nil
+}
+
+// String type of broker
+func (p *bro) String() string { return p.name }
+
+type fsmT struct {
+	name string
+}
+
+func (f *fsmT) Start(_ context.Context, _ interface{}, _ ...Option) (interface{}, error) {
+	return nil, nil
+}
+func (f *fsmT) Current() string                 { return f.name }
+func (f *fsmT) Reset()                          {}
+func (f *fsmT) State(_ string, _ fsm.StateFunc) {}

mtls/mtls.go

@@ -1,4 +1,4 @@
-package mtls // import "go.unistack.org/micro/v4/mtls"
+package mtls
 
 import (
 	"bytes"

mtls/options.go

@@ -8,17 +8,18 @@ import (
 
 // CertificateOptions holds options for x509.CreateCertificate
 type CertificateOptions struct {
-	Organization          []string
-	OrganizationalUnit    []string
-	CommonName            string
-	OCSPServer            []string
-	IssuingCertificateURL []string
 	SerialNumber          *big.Int
 	NotAfter              time.Time
 	NotBefore             time.Time
+	CommonName            string
+	Organization          []string
+	OrganizationalUnit    []string
+	OCSPServer            []string
+	IssuingCertificateURL []string
+	ExtKeyUsage           []x509.ExtKeyUsage
+
 	SignatureAlgorithm x509.SignatureAlgorithm
 	PublicKeyAlgorithm x509.PublicKeyAlgorithm
-	ExtKeyUsage           []x509.ExtKeyUsage
 	KeyUsage           x509.KeyUsage
 	IsCA               bool
 }

options.go

@@ -11,7 +11,6 @@ import (
 	"go.unistack.org/micro/v4/logger"
 	"go.unistack.org/micro/v4/metadata"
 	"go.unistack.org/micro/v4/meter"
-	"go.unistack.org/micro/v4/options"
 	"go.unistack.org/micro/v4/register"
 	"go.unistack.org/micro/v4/router"
 	"go.unistack.org/micro/v4/server"
@@ -91,7 +90,33 @@ type Option func(*Options) error
 // Broker to be used for client and server
 func Broker(b broker.Broker, opts ...BrokerOption) Option {
 	return func(o *Options) error {
-		o.Brokers = []broker.Broker{b}
+		var err error
+		bopts := brokerOptions{}
+		for _, opt := range opts {
+			opt(&bopts)
+		}
+		all := false
+		if len(opts) == 0 {
+			all = true
+		}
+		for _, srv := range o.Servers {
+			for _, os := range bopts.servers {
+				if srv.Name() == os || all {
+					if err = srv.Init(server.Broker(b)); err != nil {
+						return err
+					}
+				}
+			}
+		}
+		for _, cli := range o.Clients {
+			for _, oc := range bopts.clients {
+				if cli.Name() == oc || all {
+					if err = cli.Init(client.Broker(b)); err != nil {
+						return err
+					}
+				}
+			}
+		}
 		return nil
 	}
 }
@@ -202,7 +227,7 @@ func Logger(l logger.Logger, opts ...LoggerOption) Option {
 		for _, srv := range o.Servers {
 			for _, os := range lopts.servers {
 				if srv.Name() == os || all {
-					if err = srv.Init(options.Logger(l)); err != nil {
+					if err = srv.Init(server.Logger(l)); err != nil {
 						return err
 					}
 				}
@@ -211,7 +236,7 @@ func Logger(l logger.Logger, opts ...LoggerOption) Option {
 		for _, cli := range o.Clients {
 			for _, oc := range lopts.clients {
 				if cli.Name() == oc || all {
-					if err = cli.Init(options.Logger(l)); err != nil {
+					if err = cli.Init(client.Logger(l)); err != nil {
 						return err
 					}
 				}
@@ -220,7 +245,7 @@ func Logger(l logger.Logger, opts ...LoggerOption) Option {
 		for _, brk := range o.Brokers {
 			for _, ob := range lopts.brokers {
 				if brk.Name() == ob || all {
-					if err = brk.Init(options.Logger(l)); err != nil {
+					if err = brk.Init(broker.Logger(l)); err != nil {
 						return err
 					}
 				}
@@ -238,25 +263,17 @@ func Logger(l logger.Logger, opts ...LoggerOption) Option {
 		for _, str := range o.Stores {
 			for _, or := range lopts.stores {
 				if str.Name() == or || all {
-					if err = str.Init(options.Logger(l)); err != nil {
+					if err = str.Init(store.Logger(l)); err != nil {
-						return err
-					}
-				}
-			}
-		}
-		for _, mtr := range o.Meters {
-			for _, or := range lopts.meters {
-				if mtr.Name() == or || all {
-					if err = mtr.Init(options.Logger(l)); err != nil {
 						return err
 					}
 				}
 			}
 		}
+
 		for _, trc := range o.Tracers {
 			for _, ot := range lopts.tracers {
 				if trc.Name() == ot || all {
-					if err = trc.Init(options.Logger(l)); err != nil {
+					if err = trc.Init(tracer.Logger(l)); err != nil {
 						return err
 					}
 				}
@@ -277,7 +294,7 @@ type loggerOptions struct {
 	brokers   []string
 	registers []string
 	stores    []string
-	meters    []string
+	// meters    []string
 	tracers []string
 }
 
@@ -330,7 +347,7 @@ func Register(r register.Register, opts ...RegisterOption) Option {
 		for _, srv := range o.Servers {
 			for _, os := range ropts.servers {
 				if srv.Name() == os || all {
-					if err = srv.Init(options.Register(r)); err != nil {
+					if err = srv.Init(server.Register(r)); err != nil {
 						return err
 					}
 				}
@@ -339,7 +356,7 @@ func Register(r register.Register, opts ...RegisterOption) Option {
 		for _, brk := range o.Brokers {
 			for _, os := range ropts.brokers {
 				if brk.Name() == os || all {
-					if err = brk.Init(options.Register(r)); err != nil {
+					if err = brk.Init(broker.Register(r)); err != nil {
 						return err
 					}
 				}
@@ -396,7 +413,7 @@ func Tracer(t tracer.Tracer, opts ...TracerOption) Option {
 		for _, srv := range o.Servers {
 			for _, os := range topts.servers {
 				if srv.Name() == os || all {
-					if err = srv.Init(options.Tracer(t)); err != nil {
+					if err = srv.Init(server.Tracer(t)); err != nil {
 						return err
 					}
 				}
@@ -405,7 +422,7 @@ func Tracer(t tracer.Tracer, opts ...TracerOption) Option {
 		for _, cli := range o.Clients {
 			for _, os := range topts.clients {
 				if cli.Name() == os || all {
-					if err = cli.Init(options.Tracer(t)); err != nil {
+					if err = cli.Init(client.Tracer(t)); err != nil {
 						return err
 					}
 				}
@@ -414,7 +431,7 @@ func Tracer(t tracer.Tracer, opts ...TracerOption) Option {
 		for _, str := range o.Stores {
 			for _, os := range topts.stores {
 				if str.Name() == os || all {
-					if err = str.Init(options.Tracer(t)); err != nil {
+					if err = str.Init(store.Tracer(t)); err != nil {
 						return err
 					}
 				}
@@ -423,7 +440,7 @@ func Tracer(t tracer.Tracer, opts ...TracerOption) Option {
 		for _, brk := range o.Brokers {
 			for _, os := range topts.brokers {
 				if brk.Name() == os || all {
-					if err = brk.Init(options.Tracer(t)); err != nil {
+					if err = brk.Init(broker.Tracer(t)); err != nil {
 						return err
 					}
 				}
@@ -522,7 +539,7 @@ func Router(r router.Router, opts ...RouterOption) Option {
 		for _, cli := range o.Clients {
 			for _, os := range ropts.clients {
 				if cli.Name() == os || all {
-					if err = cli.Init(options.Router(r)); err != nil {
+					if err = cli.Init(client.Router(r)); err != nil {
 						return err
 					}
 				}
@@ -557,7 +574,7 @@ func Address(addr string) Option {
 		default:
 			return fmt.Errorf("cant set same address for multiple servers")
 		}
-		return o.Servers[0].Init(options.Address(addr))
+		return o.Servers[0].Init(server.Address(addr))
 	}
 }
 

options/hooks.go

@@ -1,4 +1,4 @@
-package options // import "go.unistack.org/micro/v4/options"
+package options
 
 // Hook func interface
 type Hook interface{}

options/options.go

@@ -1,189 +1,222 @@
 package options
 
 import (
-	"context"
-	"crypto/tls"
 	"reflect"
+	"strings"
 	"time"
 
-	"go.unistack.org/micro/v4/metadata"
+	"github.com/spf13/cast"
-	rutil "go.unistack.org/micro/v4/util/reflect"
+	mreflect "go.unistack.org/micro/v4/util/reflect"
 )
 
+// Options interface must be used by all options
+type Validator interface {
+	// Validate returns nil, if all options are correct,
+	// otherwise returns an error explaining the mistake
+	Validate() error
+}
+
 // Option func signature
 type Option func(interface{}) error
 
-// Set assign value to struct by its path
+// Apply assign options to struct src
-func Set(src interface{}, dst interface{}, path string) error {
+func Apply(src interface{}, opts ...Option) error {
-	return rutil.SetFieldByPath(src, dst, path)
+	for _, opt := range opts {
-}
+		if err := opt(src); err != nil {
-
-// Get returns value from struct by its path
-func Get(src interface{}, path string) (interface{}, error) {
-	return rutil.StructFieldByPath(src, path)
-}
-
-// Name set Name value
-func Name(v ...string) Option {
-	return func(src interface{}) error {
-		return Set(src, v, ".Name")
-	}
-}
-
-// Address set Address value to single string or slice of strings
-func Address(v ...string) Option {
-	return func(src interface{}) error {
-		return Set(src, v, ".Address")
-	}
-}
-
-// Broker set Broker value
-func Broker(v interface{}) Option {
-	return func(src interface{}) error {
-		return Set(src, v, ".Broker")
-	}
-}
-
-// Logger set Logger value
-func Logger(v interface{}) Option {
-	return func(src interface{}) error {
-		return Set(src, v, ".Logger")
-	}
-}
-
-// Meter set Meter value
-func Meter(v interface{}) Option {
-	return func(src interface{}) error {
-		return Set(src, v, ".Meter")
-	}
-}
-
-// Tracer set Tracer value
-func Tracer(v interface{}) Option {
-	return func(src interface{}) error {
-		return Set(src, v, ".Tracer")
-	}
-}
-
-// Store set Store value
-func Store(v interface{}) Option {
-	return func(src interface{}) error {
-		return Set(src, v, ".Store")
-	}
-}
-
-// Register set Register value
-func Register(v interface{}) Option {
-	return func(src interface{}) error {
-		return Set(src, v, ".Register")
-	}
-}
-
-// Router set Router value
-func Router(v interface{}) Option {
-	return func(src interface{}) error {
-		return Set(src, v, ".Router")
-	}
-}
-
-// Codec set Codec value
-func Codec(v interface{}) Option {
-	return func(src interface{}) error {
-		return Set(src, v, ".Codec")
-	}
-}
-
-// Client set Client value
-func Client(v interface{}) Option {
-	return func(src interface{}) error {
-		return Set(src, v, ".Client")
-	}
-}
-
-// Codecs to be used to encode/decode requests for a given content type
-func Codecs(ct string, v interface{}) Option {
-	return func(src interface{}) error {
-		cm, err := Get(src, ".Codecs")
-		if err != nil {
 			return err
-		} else if rutil.IsZero(cm) {
-			cm = reflect.MakeMap(reflect.TypeOf(cm)).Interface()
 		}
-		cv := reflect.ValueOf(cm)
-		cv.SetMapIndex(reflect.ValueOf(ct), reflect.ValueOf(v))
-		return Set(src, cv.Interface(), ".Codecs")
 	}
+	return nil
 }
 
-// Context set Context value
+// SetValueByPath set src struct field to val dst via path
-func Context(v context.Context) Option {
+func SetValueByPath(src interface{}, dst interface{}, path string) error {
-	return func(src interface{}) error {
+	var err error
-		return Set(src, v, ".Context")
-	}
-}
 
-// TLSConfig set TLSConfig value
+	switch v := dst.(type) {
-func TLSConfig(v *tls.Config) Option {
+	case []interface{}:
-	return func(src interface{}) error {
+		if len(v) == 1 {
-		return Set(src, v, ".TLSConfig")
+			dst = v[0]
+		}
 	}
-}
 
-func ContextOption(k, v interface{}) Option {
+	var sv reflect.Value
-	return func(src interface{}) error {
+	switch t := src.(type) {
-		ctx, err := Get(src, ".Context")
+	case reflect.Value:
+		sv = t
+	default:
+		sv = reflect.ValueOf(src)
+	}
+
+	parts := strings.Split(path, ".")
+
+	for _, p := range parts {
+
+		if sv.Kind() == reflect.Ptr {
+			sv = sv.Elem()
+		}
+		if sv.Kind() != reflect.Struct {
+			return mreflect.ErrInvalidStruct
+		}
+
+		typ := sv.Type()
+		for idx := 0; idx < typ.NumField(); idx++ {
+			fld := typ.Field(idx)
+			val := sv.Field(idx)
+
+			/*
+				if len(fld.PkgPath) != 0 {
+					continue
+				}
+			*/
+
+			if fld.Anonymous {
+				if len(parts) == 1 && val.Kind() == reflect.Struct {
+					if err = SetValueByPath(val, dst, p); err != nil {
+						return err
+					}
+				}
+			}
+
+			if fld.Name != p && !strings.EqualFold(strings.ToLower(fld.Name), strings.ToLower(p)) {
+				continue
+			}
+
+			switch val.Interface().(type) {
+			case []time.Duration:
+				dst, err = cast.ToDurationSliceE(dst)
 				if err != nil {
 					return err
 				}
-		if ctx == nil {
+				reflect.Copy(val, reflect.ValueOf(dst))
-			ctx = context.Background()
+				return nil
-		}
+			case time.Duration:
-		err = Set(src, context.WithValue(ctx.(context.Context), k, v), ".Context")
+				dst, err = cast.ToDurationE(dst)
-		return err
-	}
-}
-
-// ContentType pass ContentType for message data
-func ContentType(ct string) Option {
-	return func(src interface{}) error {
-		return Set(src, ct, ".ContentType")
-	}
-}
-
-// Metadata pass additional metadata
-func Metadata(md metadata.Metadata) Option {
-	return func(src interface{}) error {
-		return Set(src, metadata.Copy(md), ".Metadata")
-	}
-}
-
-// Namespace to use
-func Namespace(ns string) Option {
-	return func(src interface{}) error {
-		return Set(src, ns, ".Namespace")
-	}
-}
-
-// Labels sets the labels
-func Labels(ls ...interface{}) Option {
-	return func(src interface{}) error {
-		v, err := Get(src, ".Labels")
 				if err != nil {
 					return err
-		} else if rutil.IsZero(v) {
-			v = reflect.MakeSlice(reflect.TypeOf(v), 0, len(ls)).Interface()
 				}
-		cv := reflect.ValueOf(v)
+				val.Set(reflect.ValueOf(dst))
-		for _, l := range ls {
+				return nil
-			cv = reflect.Append(cv, reflect.ValueOf(l))
+			case time.Time:
+				dst, err = cast.ToTimeE(dst)
+				if err != nil {
+					return err
+				}
+				val.Set(reflect.ValueOf(dst))
+				return nil
+			}
+
+			switch val.Kind() {
+			case reflect.Map:
+				if val.IsZero() {
+					val.Set(reflect.MakeMap(val.Type()))
+				}
+
+				return setMap(val.Interface(), dst)
+			case reflect.Array, reflect.Slice:
+				switch val.Type().Elem().Kind() {
+				case reflect.Bool:
+					dst, err = cast.ToBoolSliceE(dst)
+				case reflect.String:
+					dst, err = cast.ToStringSliceE(dst)
+				case reflect.Float32:
+					dst, err = toFloat32SliceE(dst)
+				case reflect.Float64:
+					dst, err = toFloat64SliceE(dst)
+				case reflect.Int8:
+					dst, err = toInt8SliceE(dst)
+				case reflect.Int:
+					dst, err = cast.ToIntSliceE(dst)
+				case reflect.Int16:
+					dst, err = toInt16SliceE(dst)
+				case reflect.Int32:
+					dst, err = toInt32SliceE(dst)
+				case reflect.Int64:
+					dst, err = toInt64SliceE(dst)
+				case reflect.Uint8:
+					dst, err = toUint8SliceE(dst)
+				case reflect.Uint:
+					dst, err = toUintSliceE(dst)
+				case reflect.Uint16:
+					dst, err = toUint16SliceE(dst)
+				case reflect.Uint32:
+					dst, err = toUint32SliceE(dst)
+				case reflect.Uint64:
+					dst, err = toUint64SliceE(dst)
+				}
+				if err != nil {
+					return err
+				}
+				if val.Kind() == reflect.Slice {
+					val.Set(reflect.ValueOf(dst))
+				} else {
+					reflect.Copy(val, reflect.ValueOf(dst))
+				}
+				return nil
+			case reflect.Float32:
+				dst, err = toFloat32SliceE(dst)
+			case reflect.Float64:
+				dst, err = toFloat64SliceE(dst)
+			case reflect.Bool:
+				dst, err = cast.ToBoolE(dst)
+			case reflect.String:
+				dst, err = cast.ToStringE(dst)
+			case reflect.Int8:
+				dst, err = cast.ToInt8E(dst)
+			case reflect.Int:
+				dst, err = cast.ToIntE(dst)
+			case reflect.Int16:
+				dst, err = cast.ToInt16E(dst)
+			case reflect.Int32:
+				dst, err = cast.ToInt32E(dst)
+			case reflect.Int64:
+				dst, err = cast.ToInt64E(dst)
+			case reflect.Uint8:
+				dst, err = cast.ToUint8E(dst)
+			case reflect.Uint:
+				dst, err = cast.ToUintE(dst)
+			case reflect.Uint16:
+				dst, err = cast.ToUint16E(dst)
+			case reflect.Uint32:
+				dst, err = cast.ToUint32E(dst)
+			case reflect.Uint64:
+				dst, err = cast.ToUint64E(dst)
+			default:
+			}
+			if err != nil {
+				return err
+			}
+			val.Set(reflect.ValueOf(dst))
+		}
+	}
+
+	return nil
+}
+
+// NewOption create new option with name
+func NewOption(name string) func(...interface{}) Option {
+	return func(dst ...interface{}) Option {
+		return func(src interface{}) error {
+			return SetValueByPath(src, dst, name)
 		}
-		return Set(src, cv.Interface(), ".Labels")
 	}
 }
 
-// Timeout pass timeout time.Duration
+var (
-func Timeout(td time.Duration) Option {
+	Address   = NewOption("Address")
-	return func(src interface{}) error {
+	Name      = NewOption("Name")
-		return Set(src, td, ".Timeout")
+	Broker    = NewOption("Broker")
-	}
+	Logger    = NewOption("Logger")
-}
+	Meter     = NewOption("Meter")
+	Tracer    = NewOption("Tracer")
+	Store     = NewOption("Store")
+	Register  = NewOption("Register")
+	Router    = NewOption("Router")
+	Codec     = NewOption("Codec")
+	Codecs    = NewOption("Codecs")
+	Client    = NewOption("Client")
+	Context   = NewOption("Context")
+	TLSConfig = NewOption("TLSConfig")
+	Metadata  = NewOption("Metadata")
+	Timeout   = NewOption("Timeout")
+)

options/options_test.go

@@ -1,86 +1,181 @@
 package options_test
 
 import (
+	"crypto/tls"
+	"sync"
 	"testing"
 
-	"go.unistack.org/micro/v4/codec"
 	"go.unistack.org/micro/v4/options"
 )
 
-func TestAddress(t *testing.T) {
+type codec interface {
-	var err error
+	Marshal(v interface{}, opts ...options.Option) ([]byte, error)
+	Unmarshal(b []byte, v interface{}, opts ...options.Option) error
+	String() string
+}
 
+func TestCodecs(t *testing.T) {
+	type s struct {
+		Codecs map[string]codec
+	}
+
+	wg := &sync.WaitGroup{}
+	tc := &tls.Config{InsecureSkipVerify: true}
+	opts := []options.Option{
+		options.NewOption("Codecs")(wg),
+		options.NewOption("TLSConfig")(tc),
+	}
+
+	src := &s{}
+
+	if err := options.Apply(src, opts...); err != nil {
+		t.Fatal(err)
+	}
+}
+
+func TestSpecial(t *testing.T) {
+	type s struct {
+		Wait      *sync.WaitGroup
+		TLSConfig *tls.Config
+	}
+
+	wg := &sync.WaitGroup{}
+	tc := &tls.Config{InsecureSkipVerify: true}
+	opts := []options.Option{
+		options.NewOption("Wait")(wg),
+		options.NewOption("TLSConfig")(tc),
+	}
+
+	src := &s{}
+
+	if err := options.Apply(src, opts...); err != nil {
+		t.Fatal(err)
+	}
+
+	if src.Wait == nil {
+		t.Fatalf("failed to set Wait %#+v", src)
+	}
+
+	if src.TLSConfig == nil {
+		t.Fatalf("failed to set TLSConfig %#+v", src)
+	}
+
+	if src.TLSConfig.InsecureSkipVerify != true {
+		t.Fatalf("failed to set TLSConfig %#+v", src)
+	}
+}
+
+func TestNested(t *testing.T) {
+	type server struct {
+		Address []string
+	}
+	type ownserver struct {
+		server
+		OwnField string
+	}
+
+	opts := []options.Option{
+		options.Address("host:port"),
+		options.NewOption("OwnField")("fieldval"),
+	}
+
+	src := &ownserver{}
+
+	if err := options.Apply(src, opts...); err != nil {
+		t.Fatal(err)
+	}
+
+	if src.Address[0] != "host:port" {
+		t.Fatalf("failed to set Address %#+v", src)
+	}
+
+	if src.OwnField != "fieldval" {
+		t.Fatalf("failed to set OwnField %#+v", src)
+	}
+}
+
+func TestAddress(t *testing.T) {
 	type s struct {
 		Address []string
 	}
 
-	src := &s{}
+	opts := []options.Option{options.Address("host:port")}
-	var opts []options.Option
-	opts = append(opts, options.Address("host:port"))
 
-	for _, o := range opts {
+	src := &s{}
-		if err = o(src); err != nil {
+
+	if err := options.Apply(src, opts...); err != nil {
 		t.Fatal(err)
 	}
-	}
 
 	if src.Address[0] != "host:port" {
-		t.Fatal("failed to set Address")
+		t.Fatalf("failed to set Address %#+v", src)
 	}
 }
 
-func TestCodecs(t *testing.T) {
+func TestNewOption(t *testing.T) {
-	var err error
-
 	type s struct {
-		Codecs map[string]codec.Codec
+		Address []string
+	}
+
+	opts := []options.Option{options.NewOption("Address")("host1:port1", "host2:port2")}
+
+	src := &s{}
+
+	if err := options.Apply(src, opts...); err != nil {
+		t.Fatal(err)
+	}
+
+	if src.Address[0] != "host1:port1" {
+		t.Fatalf("failed to set Address %#+v", src)
+	}
+	if src.Address[1] != "host2:port2" {
+		t.Fatalf("failed to set Address %#+v", src)
+	}
+}
+
+func TestArray(t *testing.T) {
+	type s struct {
+		Address [1]string
+	}
+
+	opts := []options.Option{options.NewOption("Address")("host:port", "host1:port1")}
+
+	src := &s{}
+
+	if err := options.Apply(src, opts...); err != nil {
+		t.Fatal(err)
+	}
+
+	if src.Address[0] != "host:port" {
+		t.Fatalf("failed to set Address %#+v", src)
+	}
+}
+
+func TestMap(t *testing.T) {
+	type s struct {
+		Metadata map[string]string
+	}
+
+	opts := []options.Option{
+		options.NewOption("Metadata")("key1", "val1"),
+		options.NewOption("Metadata")(map[string]string{"key2": "val2"}),
 	}
 
 	src := &s{}
-	var opts []options.Option
-	c := codec.NewCodec()
-	opts = append(opts, options.Codecs("text/html", c))
 
-	for _, o := range opts {
+	if err := options.Apply(src, opts...); err != nil {
-		if err = o(src); err != nil {
 		t.Fatal(err)
 	}
+
+	if len(src.Metadata) != 2 {
+		t.Fatalf("failed to set Metadata %#+v", src)
 	}
 
-	for k, v := range src.Codecs {
+	if src.Metadata["key1"] != "val1" {
-		if k != "text/html" || v != c {
+		t.Fatalf("failed to set Metadata %#+v", src)
-			continue
-		}
-		return
 	}
 
-	t.Fatalf("failed to set Codecs")
+	if src.Metadata["key2"] != "val2" {
-}
+		t.Fatalf("failed to set Metadata %#+v", src)
-
-func TestLabels(t *testing.T) {
-	type str1 struct {
-		Labels []string
-	}
-	type str2 struct {
-		Labels []interface{}
-	}
-
-	x1 := &str1{}
-
-	if err := options.Labels("one", "two")(x1); err != nil {
-		t.Fatal(err)
-	}
-	if len(x1.Labels) != 2 {
-		t.Fatal("failed to set labels")
-	}
-	x2 := &str2{}
-	if err := options.Labels("key", "val")(x2); err != nil {
-		t.Fatal(err)
-	}
-	if len(x2.Labels) != 2 {
-		t.Fatal("failed to set labels")
-	}
-	if x2.Labels[0] != "key" {
-		t.Fatal("failed to set labels")
 	}
 }

options/util.go

@@ -0,0 +1,577 @@
+package options
+
+import (
+	"fmt"
+	"reflect"
+
+	"github.com/spf13/cast"
+)
+
+func toInt8SliceE(i interface{}) ([]int8, error) {
+	if i == nil {
+		return []int8{}, fmt.Errorf("unable to cast %#v of type %T to []int8", i, i)
+	}
+
+	switch v := i.(type) {
+	case []int8:
+		return v, nil
+	}
+
+	kind := reflect.TypeOf(i).Kind()
+	switch kind {
+	case reflect.Slice, reflect.Array:
+		s := reflect.ValueOf(i)
+		a := make([]int8, s.Len())
+		for j := 0; j < s.Len(); j++ {
+			val, err := cast.ToInt8E(s.Index(j).Interface())
+			if err != nil {
+				return []int8{}, fmt.Errorf("unable to cast %#v of type %T to []int8", i, i)
+			}
+			a[j] = val
+		}
+		return a, nil
+	default:
+		return []int8{}, fmt.Errorf("unable to cast %#v of type %T to []int8", i, i)
+	}
+}
+
+func toInt16SliceE(i interface{}) ([]int16, error) {
+	if i == nil {
+		return []int16{}, fmt.Errorf("unable to cast %#v of type %T to []int16", i, i)
+	}
+
+	switch v := i.(type) {
+	case []int16:
+		return v, nil
+	}
+
+	kind := reflect.TypeOf(i).Kind()
+	switch kind {
+	case reflect.Slice, reflect.Array:
+		s := reflect.ValueOf(i)
+		a := make([]int16, s.Len())
+		for j := 0; j < s.Len(); j++ {
+			val, err := cast.ToInt16E(s.Index(j).Interface())
+			if err != nil {
+				return []int16{}, fmt.Errorf("unable to cast %#v of type %T to []int16", i, i)
+			}
+			a[j] = val
+		}
+		return a, nil
+	default:
+		return []int16{}, fmt.Errorf("unable to cast %#v of type %T to []int16", i, i)
+	}
+}
+
+func toInt32SliceE(i interface{}) ([]int32, error) {
+	if i == nil {
+		return []int32{}, fmt.Errorf("unable to cast %#v of type %T to []int32", i, i)
+	}
+
+	switch v := i.(type) {
+	case []int32:
+		return v, nil
+	}
+
+	kind := reflect.TypeOf(i).Kind()
+	switch kind {
+	case reflect.Slice, reflect.Array:
+		s := reflect.ValueOf(i)
+		a := make([]int32, s.Len())
+		for j := 0; j < s.Len(); j++ {
+			val, err := cast.ToInt32E(s.Index(j).Interface())
+			if err != nil {
+				return []int32{}, fmt.Errorf("unable to cast %#v of type %T to []int32", i, i)
+			}
+			a[j] = val
+		}
+		return a, nil
+	default:
+		return []int32{}, fmt.Errorf("unable to cast %#v of type %T to []int32", i, i)
+	}
+}
+
+func toInt64SliceE(i interface{}) ([]int64, error) {
+	if i == nil {
+		return []int64{}, fmt.Errorf("unable to cast %#v of type %T to []int64", i, i)
+	}
+
+	switch v := i.(type) {
+	case []int64:
+		return v, nil
+	}
+
+	kind := reflect.TypeOf(i).Kind()
+	switch kind {
+	case reflect.Slice, reflect.Array:
+		s := reflect.ValueOf(i)
+		a := make([]int64, s.Len())
+		for j := 0; j < s.Len(); j++ {
+			val, err := cast.ToInt64E(s.Index(j).Interface())
+			if err != nil {
+				return []int64{}, fmt.Errorf("unable to cast %#v of type %T to []int64", i, i)
+			}
+			a[j] = val
+		}
+		return a, nil
+	default:
+		return []int64{}, fmt.Errorf("unable to cast %#v of type %T to []int64", i, i)
+	}
+}
+
+func toUintSliceE(i interface{}) ([]uint, error) {
+	if i == nil {
+		return []uint{}, fmt.Errorf("unable to cast %#v of type %T to []uint", i, i)
+	}
+
+	switch v := i.(type) {
+	case []uint:
+		return v, nil
+	}
+
+	kind := reflect.TypeOf(i).Kind()
+	switch kind {
+	case reflect.Slice, reflect.Array:
+		s := reflect.ValueOf(i)
+		a := make([]uint, s.Len())
+		for j := 0; j < s.Len(); j++ {
+			val, err := cast.ToUintE(s.Index(j).Interface())
+			if err != nil {
+				return []uint{}, fmt.Errorf("unable to cast %#v of type %T to []uint", i, i)
+			}
+			a[j] = val
+		}
+		return a, nil
+	default:
+		return []uint{}, fmt.Errorf("unable to cast %#v of type %T to []uint", i, i)
+	}
+}
+
+func toUint8SliceE(i interface{}) ([]uint8, error) {
+	if i == nil {
+		return []uint8{}, fmt.Errorf("unable to cast %#v of type %T to []uint8", i, i)
+	}
+
+	switch v := i.(type) {
+	case []uint8:
+		return v, nil
+	}
+
+	kind := reflect.TypeOf(i).Kind()
+	switch kind {
+	case reflect.Slice, reflect.Array:
+		s := reflect.ValueOf(i)
+		a := make([]uint8, s.Len())
+		for j := 0; j < s.Len(); j++ {
+			val, err := cast.ToUint8E(s.Index(j).Interface())
+			if err != nil {
+				return []uint8{}, fmt.Errorf("unable to cast %#v of type %T to []uint8", i, i)
+			}
+			a[j] = val
+		}
+		return a, nil
+	default:
+		return []uint8{}, fmt.Errorf("unable to cast %#v of type %T to []uint8", i, i)
+	}
+}
+
+func toUint16SliceE(i interface{}) ([]uint16, error) {
+	if i == nil {
+		return []uint16{}, fmt.Errorf("unable to cast %#v of type %T to []uint16", i, i)
+	}
+
+	switch v := i.(type) {
+	case []uint16:
+		return v, nil
+	}
+
+	kind := reflect.TypeOf(i).Kind()
+	switch kind {
+	case reflect.Slice, reflect.Array:
+		s := reflect.ValueOf(i)
+		a := make([]uint16, s.Len())
+		for j := 0; j < s.Len(); j++ {
+			val, err := cast.ToUint16E(s.Index(j).Interface())
+			if err != nil {
+				return []uint16{}, fmt.Errorf("unable to cast %#v of type %T to []uint16", i, i)
+			}
+			a[j] = val
+		}
+		return a, nil
+	default:
+		return []uint16{}, fmt.Errorf("unable to cast %#v of type %T to []uint16", i, i)
+	}
+}
+
+func toUint32SliceE(i interface{}) ([]uint32, error) {
+	if i == nil {
+		return []uint32{}, fmt.Errorf("unable to cast %#v of type %T to []uint32", i, i)
+	}
+
+	switch v := i.(type) {
+	case []uint32:
+		return v, nil
+	}
+
+	kind := reflect.TypeOf(i).Kind()
+	switch kind {
+	case reflect.Slice, reflect.Array:
+		s := reflect.ValueOf(i)
+		a := make([]uint32, s.Len())
+		for j := 0; j < s.Len(); j++ {
+			val, err := cast.ToUint32E(s.Index(j).Interface())
+			if err != nil {
+				return []uint32{}, fmt.Errorf("unable to cast %#v of type %T to []uint32", i, i)
+			}
+			a[j] = val
+		}
+		return a, nil
+	default:
+		return []uint32{}, fmt.Errorf("unable to cast %#v of type %T to []uint32", i, i)
+	}
+}
+
+func toUint64SliceE(i interface{}) ([]uint64, error) {
+	if i == nil {
+		return []uint64{}, fmt.Errorf("unable to cast %#v of type %T to []uint64", i, i)
+	}
+
+	switch v := i.(type) {
+	case []uint64:
+		return v, nil
+	}
+
+	kind := reflect.TypeOf(i).Kind()
+	switch kind {
+	case reflect.Slice, reflect.Array:
+		s := reflect.ValueOf(i)
+		a := make([]uint64, s.Len())
+		for j := 0; j < s.Len(); j++ {
+			val, err := cast.ToUint64E(s.Index(j).Interface())
+			if err != nil {
+				return []uint64{}, fmt.Errorf("unable to cast %#v of type %T to []uint64", i, i)
+			}
+			a[j] = val
+		}
+		return a, nil
+	default:
+		return []uint64{}, fmt.Errorf("unable to cast %#v of type %T to []uint64", i, i)
+	}
+}
+
+func toFloat32SliceE(i interface{}) ([]float32, error) {
+	if i == nil {
+		return []float32{}, fmt.Errorf("unable to cast %#v of type %T to []float32", i, i)
+	}
+
+	switch v := i.(type) {
+	case []float32:
+		return v, nil
+	}
+
+	kind := reflect.TypeOf(i).Kind()
+	switch kind {
+	case reflect.Slice, reflect.Array:
+		s := reflect.ValueOf(i)
+		a := make([]float32, s.Len())
+		for j := 0; j < s.Len(); j++ {
+			val, err := cast.ToFloat32E(s.Index(j).Interface())
+			if err != nil {
+				return []float32{}, fmt.Errorf("unable to cast %#v of type %T to []float32", i, i)
+			}
+			a[j] = val
+		}
+		return a, nil
+	default:
+		return []float32{}, fmt.Errorf("unable to cast %#v of type %T to []float32", i, i)
+	}
+}
+
+func toFloat64SliceE(i interface{}) ([]float64, error) {
+	if i == nil {
+		return []float64{}, fmt.Errorf("unable to cast %#v of type %T to []float64", i, i)
+	}
+
+	switch v := i.(type) {
+	case []float64:
+		return v, nil
+	}
+
+	kind := reflect.TypeOf(i).Kind()
+	switch kind {
+	case reflect.Slice, reflect.Array:
+		s := reflect.ValueOf(i)
+		a := make([]float64, s.Len())
+		for j := 0; j < s.Len(); j++ {
+			val, err := cast.ToFloat64E(s.Index(j).Interface())
+			if err != nil {
+				return []float64{}, fmt.Errorf("unable to cast %#v of type %T to []float64", i, i)
+			}
+			a[j] = val
+		}
+		return a, nil
+	default:
+		return []float64{}, fmt.Errorf("unable to cast %#v of type %T to []float32", i, i)
+	}
+}
+
+func setMap(src interface{}, dst interface{}) error {
+	var err error
+
+	if src == nil {
+		return fmt.Errorf("unable to cast %#v of type %T", src, src)
+	}
+	if dst == nil {
+		return fmt.Errorf("unable to cast %#v of type %T", dst, dst)
+	}
+
+	val := reflect.ValueOf(src)
+
+	keyKind := val.Type().Key().Kind()
+	valKind := val.Type().Elem().Kind()
+
+	switch v := dst.(type) {
+	case []interface{}:
+		if len(v) == 1 {
+			dstVal := reflect.ValueOf(v[0])
+			if dstVal.Kind() != reflect.Map {
+				return nil
+			}
+			mapIter := dstVal.MapRange()
+			for mapIter.Next() {
+				var (
+					keyVal interface{}
+					valVal interface{}
+				)
+				switch keyKind {
+				case reflect.Bool:
+					keyVal, err = cast.ToBoolE(mapIter.Key())
+				case reflect.String:
+					keyVal, err = cast.ToStringE(mapIter.Key())
+				case reflect.Float32:
+					keyVal, err = cast.ToFloat32E(mapIter.Key())
+				case reflect.Float64:
+					keyVal, err = cast.ToFloat64E(mapIter.Key())
+				case reflect.Int8:
+					keyVal, err = cast.ToInt8E(mapIter.Key())
+				case reflect.Int:
+					keyVal, err = cast.ToIntE(mapIter.Key())
+				case reflect.Int16:
+					keyVal, err = cast.ToInt16E(mapIter.Key())
+				case reflect.Int32:
+					keyVal, err = cast.ToInt32E(mapIter.Key())
+				case reflect.Int64:
+					keyVal, err = cast.ToInt64E(mapIter.Key())
+				case reflect.Uint8:
+					keyVal, err = cast.ToUint8E(mapIter.Key())
+				case reflect.Uint:
+					keyVal, err = cast.ToUintE(mapIter.Key())
+				case reflect.Uint16:
+					keyVal, err = cast.ToUint16E(mapIter.Key())
+				case reflect.Uint32:
+					keyVal, err = cast.ToUint32E(mapIter.Key())
+				case reflect.Uint64:
+					keyVal, err = cast.ToUint64E(mapIter.Key())
+				}
+				if err != nil {
+					return err
+				}
+				switch valKind {
+				case reflect.Bool:
+					valVal, err = cast.ToBoolE(mapIter.Value())
+				case reflect.String:
+					valVal, err = cast.ToStringE(mapIter.Value())
+				case reflect.Float32:
+					valVal, err = cast.ToFloat32E(mapIter.Value())
+				case reflect.Float64:
+					valVal, err = cast.ToFloat64E(mapIter.Value())
+				case reflect.Int8:
+					valVal, err = cast.ToInt8E(mapIter.Value())
+				case reflect.Int:
+					valVal, err = cast.ToIntE(mapIter.Value())
+				case reflect.Int16:
+					valVal, err = cast.ToInt16E(mapIter.Value())
+				case reflect.Int32:
+					valVal, err = cast.ToInt32E(mapIter.Value())
+				case reflect.Int64:
+					valVal, err = cast.ToInt64E(mapIter.Value())
+				case reflect.Uint8:
+					valVal, err = cast.ToUint8E(mapIter.Value())
+				case reflect.Uint:
+					valVal, err = cast.ToUintE(mapIter.Value())
+				case reflect.Uint16:
+					valVal, err = cast.ToUint16E(mapIter.Value())
+				case reflect.Uint32:
+					valVal, err = cast.ToUint32E(mapIter.Value())
+				case reflect.Uint64:
+					valVal, err = cast.ToUint64E(mapIter.Value())
+				}
+				if err != nil {
+					return err
+				}
+
+				val.SetMapIndex(reflect.ValueOf(keyVal), reflect.ValueOf(valVal))
+			}
+			return nil
+		}
+		if l := len(v) % 2; l == 1 {
+			v = v[:len(v)-1]
+		}
+		var (
+			keyVal interface{}
+			valVal interface{}
+		)
+		for i := 0; i < len(v); i += 2 {
+			switch keyKind {
+			case reflect.Bool:
+				keyVal, err = cast.ToBoolE(v[i])
+			case reflect.String:
+				keyVal, err = cast.ToStringE(v[i])
+			case reflect.Float32:
+				keyVal, err = cast.ToFloat32E(v[i])
+			case reflect.Float64:
+				keyVal, err = cast.ToFloat64E(v[i])
+			case reflect.Int8:
+				keyVal, err = cast.ToInt8E(v[i])
+			case reflect.Int:
+				keyVal, err = cast.ToIntE(v[i])
+			case reflect.Int16:
+				keyVal, err = cast.ToInt16E(v[i])
+			case reflect.Int32:
+				keyVal, err = cast.ToInt32E(v[i])
+			case reflect.Int64:
+				keyVal, err = cast.ToInt64E(v[i])
+			case reflect.Uint8:
+				keyVal, err = cast.ToUint8E(v[i])
+			case reflect.Uint:
+				keyVal, err = cast.ToUintE(v[i])
+			case reflect.Uint16:
+				keyVal, err = cast.ToUint16E(v[i])
+			case reflect.Uint32:
+				keyVal, err = cast.ToUint32E(v[i])
+			case reflect.Uint64:
+				keyVal, err = cast.ToUint64E(v[i])
+			}
+			if err != nil {
+				return err
+			}
+			switch valKind {
+			case reflect.Bool:
+				valVal, err = cast.ToBoolE(v[i+1])
+			case reflect.String:
+				valVal, err = cast.ToStringE(v[i+1])
+			case reflect.Float32:
+				valVal, err = cast.ToFloat32E(v[i+1])
+			case reflect.Float64:
+				valVal, err = cast.ToFloat64E(v[i+1])
+			case reflect.Int8:
+				valVal, err = cast.ToInt8E(v[i+1])
+			case reflect.Int:
+				valVal, err = cast.ToIntE(v[i+1])
+			case reflect.Int16:
+				valVal, err = cast.ToInt16E(v[i+1])
+			case reflect.Int32:
+				valVal, err = cast.ToInt32E(v[i+1])
+			case reflect.Int64:
+				valVal, err = cast.ToInt64E(v[i+1])
+			case reflect.Uint8:
+				valVal, err = cast.ToUint8E(v[i+1])
+			case reflect.Uint:
+				valVal, err = cast.ToUintE(v[i+1])
+			case reflect.Uint16:
+				valVal, err = cast.ToUint16E(v[i+1])
+			case reflect.Uint32:
+				valVal, err = cast.ToUint32E(v[i+1])
+			case reflect.Uint64:
+				valVal, err = cast.ToUint64E(v[i+1])
+			}
+			if err != nil {
+				return err
+			}
+
+			val.SetMapIndex(reflect.ValueOf(keyVal), reflect.ValueOf(valVal))
+		}
+	default:
+		dstVal := reflect.ValueOf(dst)
+		if dstVal.Kind() != reflect.Map {
+			return nil
+		}
+		mapIter := dstVal.MapRange()
+		for mapIter.Next() {
+			var (
+				keyVal interface{}
+				valVal interface{}
+			)
+			switch keyKind {
+			case reflect.Bool:
+				keyVal, err = cast.ToBoolE(mapIter.Key())
+			case reflect.String:
+				keyVal, err = cast.ToStringE(mapIter.Key())
+			case reflect.Float32:
+				keyVal, err = cast.ToFloat32E(mapIter.Key())
+			case reflect.Float64:
+				keyVal, err = cast.ToFloat64E(mapIter.Key())
+			case reflect.Int8:
+				keyVal, err = cast.ToInt8E(mapIter.Key())
+			case reflect.Int:
+				keyVal, err = cast.ToIntE(mapIter.Key())
+			case reflect.Int16:
+				keyVal, err = cast.ToInt16E(mapIter.Key())
+			case reflect.Int32:
+				keyVal, err = cast.ToInt32E(mapIter.Key())
+			case reflect.Int64:
+				keyVal, err = cast.ToInt64E(mapIter.Key())
+			case reflect.Uint8:
+				keyVal, err = cast.ToUint8E(mapIter.Key())
+			case reflect.Uint:
+				keyVal, err = cast.ToUintE(mapIter.Key())
+			case reflect.Uint16:
+				keyVal, err = cast.ToUint16E(mapIter.Key())
+			case reflect.Uint32:
+				keyVal, err = cast.ToUint32E(mapIter.Key())
+			case reflect.Uint64:
+				keyVal, err = cast.ToUint64E(mapIter.Key())
+			}
+			if err != nil {
+				return err
+			}
+			switch valKind {
+			case reflect.Bool:
+				valVal, err = cast.ToBoolE(mapIter.Value())
+			case reflect.String:
+				valVal, err = cast.ToStringE(mapIter.Value())
+			case reflect.Float32:
+				valVal, err = cast.ToFloat32E(mapIter.Value())
+			case reflect.Float64:
+				valVal, err = cast.ToFloat64E(mapIter.Value())
+			case reflect.Int8:
+				valVal, err = cast.ToInt8E(mapIter.Value())
+			case reflect.Int:
+				valVal, err = cast.ToIntE(mapIter.Value())
+			case reflect.Int16:
+				valVal, err = cast.ToInt16E(mapIter.Value())
+			case reflect.Int32:
+				valVal, err = cast.ToInt32E(mapIter.Value())
+			case reflect.Int64:
+				valVal, err = cast.ToInt64E(mapIter.Value())
+			case reflect.Uint8:
+				valVal, err = cast.ToUint8E(mapIter.Value())
+			case reflect.Uint:
+				valVal, err = cast.ToUintE(mapIter.Value())
+			case reflect.Uint16:
+				valVal, err = cast.ToUint16E(mapIter.Value())
+			case reflect.Uint32:
+				valVal, err = cast.ToUint32E(mapIter.Value())
+			case reflect.Uint64:
+				valVal, err = cast.ToUint64E(mapIter.Value())
+			}
+			if err != nil {
+				return err
+			}
+
+			val.SetMapIndex(reflect.ValueOf(keyVal), reflect.ValueOf(valVal))
+		}
+		return nil
+	}
+	return nil
+}

profiler/http/http.go

@@ -1,5 +1,5 @@
 // Package http enables the http profiler
-package http // import "go.unistack.org/micro/v4/profiler/http"
+package http
 
 import (
 	"context"

profiler/noop.go

@@ -15,6 +15,6 @@ func (p *noopProfiler) String() string {
 }
 
 // NewProfiler returns new noop profiler
-func NewProfiler(opts ...Option) Profiler {
+func NewProfiler(_ ...Option) Profiler {
 	return &noopProfiler{}
 }

profiler/pprof/pprof.go

@@ -1,5 +1,5 @@
 // Package pprof provides a pprof profiler which writes output to /tmp/[name].{cpu,mem}.pprof
-package pprof // import "go.unistack.org/micro/v4/profiler/pprof"
+package pprof
 
 import (
 	"os"

profiler/profile.go

@@ -1,5 +1,5 @@
 // Package profiler is for profilers
-package profiler // import "go.unistack.org/micro/v4/profiler"
+package profiler
 
 // Profiler interface
 type Profiler interface {
@@ -12,7 +12,7 @@ type Profiler interface {
 }
 
 // DefaultProfiler holds the default profiler
-var DefaultProfiler Profiler = NewProfiler()
+var DefaultProfiler = NewProfiler()
 
 // Options holds the options for profiler
 type Options struct {

register/context.go

@@ -15,6 +15,15 @@ func FromContext(ctx context.Context) (Register, bool) {
 	return c, ok
 }
 
+// MustContext get register from context
+func MustContext(ctx context.Context) Register {
+	r, ok := FromContext(ctx)
+	if !ok {
+		panic("missing register")
+	}
+	return r
+}
+
 // NewContext put register in context
 func NewContext(ctx context.Context, c Register) context.Context {
 	if ctx == nil {

register/extractor.go

@@ -1,12 +1,9 @@
 package register
 
 import (
-	"fmt"
 	"reflect"
 	"unicode"
 	"unicode/utf8"
-
-	"go.unistack.org/micro/v4/metadata"
 )
 
 // ExtractValue from reflect.Type from specified depth
@@ -38,53 +35,6 @@ func ExtractValue(v reflect.Type, d int) string {
 	return v.Name()
 }
 
-// ExtractEndpoint extract *Endpoint from reflect.Method
-func ExtractEndpoint(method reflect.Method) *Endpoint {
-	if method.PkgPath != "" {
-		return nil
-	}
-
-	var rspType, reqType reflect.Type
-	var stream bool
-	mt := method.Type
-
-	switch mt.NumIn() {
-	case 3:
-		reqType = mt.In(1)
-		rspType = mt.In(2)
-	case 4:
-		reqType = mt.In(2)
-		rspType = mt.In(3)
-	default:
-		return nil
-	}
-
-	// are we dealing with a stream?
-	switch rspType.Kind() {
-	case reflect.Func, reflect.Interface:
-		stream = true
-	}
-
-	request := ExtractValue(reqType, 0)
-	response := ExtractValue(rspType, 0)
-	if request == "" || response == "" {
-		return nil
-	}
-
-	ep := &Endpoint{
-		Name:     method.Name,
-		Request:  request,
-		Response: response,
-		Metadata: metadata.New(0),
-	}
-
-	if stream {
-		ep.Metadata.Set("stream", fmt.Sprintf("%v", stream))
-	}
-
-	return ep
-}
-
 // ExtractSubValue exctact *Value from reflect.Type
 func ExtractSubValue(typ reflect.Type) string {
 	var reqType reflect.Type