codec: add MarshalAppend func

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

.github/dependabot.yml

@@ -11,9 +11,16 @@ updates:
     directory: "/"
     schedule:
       interval: "daily"
+    commit-message:
+      prefix: "chore"
+      include: "scope"
 
   # Maintain dependencies for Golang
   - package-ecosystem: "gomod"
     directory: "/"
     schedule:
       interval: "daily"
+    commit-message:
+      prefix: "chore"
+      include: "scope"
+

.github/workflows/codeql-analysis.yml

@@ -0,0 +1,75 @@
+# For most projects, this workflow file will not need changing; you simply need
+# to commit it to your repository.
+#
+# You may wish to alter this file to override the set of languages analyzed,
+# or to provide custom queries or build logic.
+#
+# ******** NOTE ********
+# We have attempted to detect the languages in your repository. Please check
+# the `language` matrix defined below to confirm you have the correct set of
+# supported CodeQL languages.
+#
+name: "CodeQL"
+
+on:
+  workflow_run:
+    workflows: ["prbuild"]
+    types:
+      - completed
+  push:
+    branches: [ master ]
+  pull_request:
+    # The branches below must be a subset of the branches above
+    branches: [ master ]
+  schedule:
+    - cron: '34 1 * * 0'
+
+jobs:
+  analyze:
+    name: Analyze
+    runs-on: ubuntu-latest
+    permissions:
+      actions: read
+      contents: read
+      security-events: write
+
+    strategy:
+      fail-fast: false
+      matrix:
+        language: [ 'go' ]
+        # CodeQL supports [ 'cpp', 'csharp', 'go', 'java', 'javascript', 'python' ]
+        # Learn more:
+        # https://docs.github.com/en/free-pro-team@latest/github/finding-security-vulnerabilities-and-errors-in-your-code/configuring-code-scanning#changing-the-languages-that-are-analyzed
+
+    steps:
+    - name: Checkout repository
+      uses: actions/checkout@v2
+
+    # Initializes the CodeQL tools for scanning.
+    - name: Initialize CodeQL
+      uses: github/codeql-action/init@v1
+      with:
+        languages: ${{ matrix.language }}
+        # If you wish to specify custom queries, you can do so here or in a config file.
+        # By default, queries listed here will override any specified in a config file.
+        # Prefix the list here with "+" to use these queries and those in the config file.
+        # queries: ./path/to/local/query, your-org/your-repo/queries@main
+
+    # Autobuild attempts to build any compiled languages  (C/C++, C#, or Java).
+    # If this step fails, then you should remove it and run the build manually (see below)
+    - name: Autobuild
+      uses: github/codeql-action/autobuild@v1
+
+    # ℹ️ Command-line programs to run using the OS shell.
+    # 📚 https://git.io/JvXDl
+
+    # ✏️ If the Autobuild fails above, remove it and uncomment the following three lines
+    #    and modify them (or add more) to build your code if your project
+    #    uses a compiled language
+
+    #- run: |
+    #   make bootstrap
+    #   make release
+
+    - name: Perform CodeQL Analysis
+      uses: github/codeql-action/analyze@v1

.github/workflows/dependabot-automerge.yml

@@ -0,0 +1,66 @@
+name: "prautomerge"
+
+on:
+  workflow_run:
+    workflows: ["prbuild"]
+    types:
+      - completed
+
+permissions:
+  contents: write
+  pull-requests: write
+
+jobs:
+  Dependabot-Automerge:
+    runs-on: ubuntu-latest
+    # Contains workaround to execute if dependabot updates the PR by checking for the base branch in the linked PR
+    # The the github.event.workflow_run.event value is 'push' and not 'pull_request'
+    # dont work with multiple workflows when last returns success
+    if: >-
+      github.event.workflow_run.conclusion == 'success'
+      && github.actor == 'dependabot[bot]'
+      && github.event.sender.login == 'dependabot[bot]'
+      && github.event.sender.type == 'Bot'
+      && (github.event.workflow_run.event == 'pull_request'
+          || (github.event.workflow_run.event == 'push' && github.event.workflow_run.pull_requests[0].base.ref == github.event.repository.default_branch ))
+    steps:
+      - name: Approve Changes and Merge changes if label 'dependencies' is set
+        uses: actions/github-script@v5
+        with:
+          github-token: ${{ secrets.GITHUB_TOKEN }}
+          script: |
+            console.log(context.payload.workflow_run);
+            
+            var labelNames = await github.paginate(
+              github.issues.listLabelsOnIssue,
+              {
+                repo: context.repo.repo,
+                owner: context.repo.owner,
+                issue_number: context.payload.workflow_run.pull_requests[0].number,
+              },
+              (response) => response.data.map(
+                (label) => label.name
+              )
+            );
+
+            console.log(labelNames);
+
+            if (labelNames.includes('dependencies')) {
+              console.log('Found label');
+
+              await github.pulls.createReview({
+                repo: context.repo.repo,
+                owner: context.repo.owner,
+                pull_number: context.payload.workflow_run.pull_requests[0].number,
+                event: 'APPROVE'
+              });
+              console.log('Approved PR');
+
+              await github.pulls.merge({
+                repo: context.repo.repo,
+                owner: context.repo.owner,
+                pull_number: context.payload.workflow_run.pull_requests[0].number,
+              });
+
+              console.log('Merged PR');
+            }

.golangci.yml

@@ -30,7 +30,7 @@ linters:
     - gofmt
     - gofumpt
     - goimports
-    - golint
+    - revive
     - gosec
     - makezero
     - misspell

SECURITY.md

@@ -0,0 +1,15 @@
+# Security Policy
+
+## Supported Versions
+
+Use this section to tell people about which versions of your project are
+currently being supported with security updates.
+
+| Version | Supported          |
+| ------- | ------------------ |
+| 3.7.x   | :white_check_mark: |
+| < 3.7.0 | :x:                |
+
+## Reporting a Vulnerability
+
+If you find any issue, please create github issue in this repo

api/api.go

@@ -10,6 +10,7 @@ import (
 	"github.com/unistack-org/micro/v3/server"
 )
 
+// nolint: revive
 // Api interface
 type Api interface {
 	// Initialise options
@@ -125,14 +126,14 @@ func Validate(e *Endpoint) error {
 		ps := p[0]
 		pe := p[len(p)-1]
 
-		if ps == '^' && pe == '$' {
-			_, err := regexp.CompilePOSIX(p)
-			if err != nil {
+		switch {
+		case ps == '^' && pe == '$':
+			if _, err := regexp.CompilePOSIX(p); err != nil {
 				return err
 			}
-		} else if ps == '^' && pe != '$' {
+		case ps == '^' && pe != '$':
 			return errors.New("invalid path")
-		} else if ps != '^' && pe == '$' {
+		case ps != '^' && pe == '$':
 			return errors.New("invalid path")
 		}
 	}

auth/auth.go

@@ -55,7 +55,7 @@ type Auth interface {
 type Account struct {
 	// Metadata any other associated metadata
 	Metadata metadata.Metadata `json:"metadata"`
-	// ID of the account e.g. email or uuid
+	// ID of the account e.g. email or id
 	ID string `json:"id"`
 	// Type of the account, e.g. service
 	Type string `json:"type"`

auth/noop.go

@@ -1,7 +1,7 @@
 package auth
 
 import (
-	"github.com/google/uuid"
+	"github.com/unistack-org/micro/v3/util/id"
 )
 
 type noopAuth struct {
@@ -61,11 +61,11 @@ func (n *noopAuth) Verify(acc *Account, res *Resource, opts ...VerifyOption) err
 
 // Inspect a token
 func (n *noopAuth) Inspect(token string) (*Account, error) {
-	uid, err := uuid.NewRandom()
+	id, err := id.New()
 	if err != nil {
 		return nil, err
 	}
-	return &Account{ID: uid.String(), Issuer: n.Options().Issuer}, nil
+	return &Account{ID: id, Issuer: n.Options().Issuer}, nil
 }
 
 // Token generation using an account id and secret

broker/broker.go

@@ -3,46 +3,128 @@ package broker
 
 import (
 	"context"
+	"errors"
 
 	"github.com/unistack-org/micro/v3/metadata"
 )
 
-// DefaultBroker default broker
+// DefaultBroker default memory broker
 var DefaultBroker Broker = NewBroker()
 
+var (
+	// ErrNotConnected returns when broker used but not connected yet
+	ErrNotConnected = errors.New("broker not connected")
+	// ErrDisconnected returns when broker disconnected
+	ErrDisconnected = errors.New("broker disconnected")
+)
+
 // Broker is an interface used for asynchronous messaging.
 type Broker interface {
+	// Name returns broker instance name
 	Name() string
-	Init(...Option) error
+	// Init initilize broker
+	Init(opts ...Option) error
+	// Options returns broker options
 	Options() Options
+	// Address return configured address
 	Address() string
-	Connect(context.Context) error
-	Disconnect(context.Context) error
-	Publish(context.Context, string, *Message, ...PublishOption) error
-	Subscribe(context.Context, string, Handler, ...SubscribeOption) (Subscriber, error)
+	// Connect connects to broker
+	Connect(ctx context.Context) error
+	// Disconnect disconnect from broker
+	Disconnect(ctx context.Context) error
+	// Publish message to broker topic
+	Publish(ctx context.Context, topic string, msg *Message, opts ...PublishOption) error
+	// Subscribe subscribes to topic message via handler
+	Subscribe(ctx context.Context, topic string, h Handler, opts ...SubscribeOption) (Subscriber, error)
+	// BatchPublish messages to broker with multiple topics
+	BatchPublish(ctx context.Context, msgs []*Message, opts ...PublishOption) error
+	// BatchSubscribe subscribes to topic messages via handler
+	BatchSubscribe(ctx context.Context, topic string, h BatchHandler, opts ...SubscribeOption) (Subscriber, error)
+	// String type of broker
 	String() string
 }
 
 // Handler is used to process messages via a subscription of a topic.
 type Handler func(Event) error
 
+// Events contains multiple events
+type Events []Event
+
+func (evs Events) Ack() error {
+	var err error
+	for _, ev := range evs {
+		if err = ev.Ack(); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func (evs Events) SetError(err error) {
+	for _, ev := range evs {
+		ev.SetError(err)
+	}
+}
+
+// BatchHandler is used to process messages in batches via a subscription of a topic.
+type BatchHandler func(Events) error
+
 // Event is given to a subscription handler for processing
 type Event interface {
+	// Topic returns event topic
 	Topic() string
+	// Message returns broker message
 	Message() *Message
+	// Ack acknowledge message
 	Ack() error
+	// Error returns message error (like decoding errors or some other)
 	Error() error
+	// SetError set event processing error
+	SetError(err error)
+}
+
+// RawMessage is a raw encoded JSON value.
+// It implements Marshaler and Unmarshaler and can be used to delay decoding or precompute a encoding.
+type RawMessage []byte
+
+// MarshalJSON returns m as the JSON encoding of m.
+func (m *RawMessage) MarshalJSON() ([]byte, error) {
+	if m == nil {
+		return []byte("null"), nil
+	}
+	return *m, nil
+}
+
+// UnmarshalJSON sets *m to a copy of data.
+func (m *RawMessage) UnmarshalJSON(data []byte) error {
+	if m == nil {
+		return errors.New("RawMessage UnmarshalJSON on nil pointer")
+	}
+	*m = append((*m)[0:0], data...)
+	return nil
 }
 
 // Message is used to transfer data
 type Message struct {
-	Header metadata.Metadata // contains message metadata
-	Body   []byte            // contains message body
+	// Header contains message metadata
+	Header metadata.Metadata
+	// Body contains message body
+	Body RawMessage
+}
+
+// NewMessage create broker message with topic filled
+func NewMessage(topic string) *Message {
+	m := &Message{Header: metadata.New(2)}
+	m.Header.Set(metadata.HeaderTopic, topic)
+	return m
 }
 
 // Subscriber is a convenience return type for the Subscribe method
 type Subscriber interface {
+	// Options returns subscriber options
 	Options() SubscribeOptions
+	// Topic returns topic for subscription
 	Topic() string
-	Unsubscribe(context.Context) error
+	// Unsubscribe from topic
+	Unsubscribe(ctx context.Context) error
 }

broker/memory.go

@@ -2,18 +2,18 @@ package broker
 
 import (
 	"context"
-	"errors"
 	"sync"
 
-	"github.com/google/uuid"
 	"github.com/unistack-org/micro/v3/logger"
+	"github.com/unistack-org/micro/v3/metadata"
 	maddr "github.com/unistack-org/micro/v3/util/addr"
+	"github.com/unistack-org/micro/v3/util/id"
 	mnet "github.com/unistack-org/micro/v3/util/net"
 	"github.com/unistack-org/micro/v3/util/rand"
 )
 
 type memoryBroker struct {
-	Subscribers map[string][]*memorySubscriber
+	subscribers map[string][]*memorySubscriber
 	addr        string
 	opts        Options
 	sync.RWMutex
@@ -28,12 +28,13 @@ type memoryEvent struct {
 }
 
 type memorySubscriber struct {
-	ctx     context.Context
-	exit    chan bool
-	handler Handler
-	id      string
-	topic   string
-	opts    SubscribeOptions
+	ctx          context.Context
+	exit         chan bool
+	handler      Handler
+	batchhandler BatchHandler
+	id           string
+	topic        string
+	opts         SubscribeOptions
 }
 
 func (m *memoryBroker) Options() Options {
@@ -77,7 +78,6 @@ func (m *memoryBroker) Disconnect(ctx context.Context) error {
 	}
 
 	m.connected = false
-
 	return nil
 }
 
@@ -89,73 +89,168 @@ func (m *memoryBroker) Init(opts ...Option) error {
 }
 
 func (m *memoryBroker) Publish(ctx context.Context, topic string, msg *Message, opts ...PublishOption) error {
+	msg.Header.Set(metadata.HeaderTopic, topic)
+	return m.publish(ctx, []*Message{msg}, opts...)
+}
+
+func (m *memoryBroker) BatchPublish(ctx context.Context, msgs []*Message, opts ...PublishOption) error {
+	return m.publish(ctx, msgs, opts...)
+}
+
+func (m *memoryBroker) publish(ctx context.Context, msgs []*Message, opts ...PublishOption) error {
 	m.RLock()
 	if !m.connected {
 		m.RUnlock()
-		return errors.New("not connected")
+		return ErrNotConnected
 	}
-
-	subs, ok := m.Subscribers[topic]
 	m.RUnlock()
-	if !ok {
-		return nil
-	}
 
-	var v interface{}
-	if m.opts.Codec != nil {
-		buf, err := m.opts.Codec.Marshal(msg)
-		if err != nil {
-			return err
+	var err error
+
+	select {
+	case <-ctx.Done():
+		return ctx.Err()
+	default:
+		options := NewPublishOptions(opts...)
+
+		msgTopicMap := make(map[string]Events)
+		for _, v := range msgs {
+			p := &memoryEvent{opts: m.opts}
+
+			if m.opts.Codec == nil || options.BodyOnly {
+				p.topic, _ = v.Header.Get(metadata.HeaderTopic)
+				p.message = v.Body
+			} else {
+				p.topic, _ = v.Header.Get(metadata.HeaderTopic)
+				p.message, err = m.opts.Codec.Marshal(v)
+				if err != nil {
+					return err
+				}
+			}
+			msgTopicMap[p.topic] = append(msgTopicMap[p.topic], p)
 		}
-		v = buf
-	} else {
-		v = msg
-	}
 
-	p := &memoryEvent{
-		topic:   topic,
-		message: v,
-		opts:    m.opts,
-	}
+		beh := m.opts.BatchErrorHandler
+		eh := m.opts.ErrorHandler
 
-	eh := m.opts.ErrorHandler
-
-	for _, sub := range subs {
-		if err := sub.handler(p); err != nil {
-			p.err = err
-			if sub.opts.ErrorHandler != nil {
-				eh = sub.opts.ErrorHandler
+		for t, ms := range msgTopicMap {
+			m.RLock()
+			subs, ok := m.subscribers[t]
+			m.RUnlock()
+			if !ok {
+				continue
 			}
-			if eh != nil {
-				eh(p)
-			} else if m.opts.Logger.V(logger.ErrorLevel) {
-				m.opts.Logger.Error(m.opts.Context, err.Error())
+
+			for _, sub := range subs {
+				if sub.opts.BatchErrorHandler != nil {
+					beh = sub.opts.BatchErrorHandler
+				}
+				if sub.opts.ErrorHandler != nil {
+					eh = sub.opts.ErrorHandler
+				}
+
+				switch {
+				// batch processing
+				case sub.batchhandler != nil:
+					if err = sub.batchhandler(ms); err != nil {
+						ms.SetError(err)
+						if beh != nil {
+							_ = beh(ms)
+						} else if m.opts.Logger.V(logger.ErrorLevel) {
+							m.opts.Logger.Error(m.opts.Context, err.Error())
+						}
+					} else if sub.opts.AutoAck {
+						if err = ms.Ack(); err != nil {
+							m.opts.Logger.Errorf(m.opts.Context, "ack failed: %v", err)
+						}
+					}
+					// single processing
+				case sub.handler != nil:
+					for _, p := range ms {
+						if err = sub.handler(p); err != nil {
+							p.SetError(err)
+							if eh != nil {
+								_ = eh(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)
+							}
+						}
+					}
+				}
 			}
-			continue
 		}
 	}
 
 	return nil
 }
 
-func (m *memoryBroker) Subscribe(ctx context.Context, topic string, handler Handler, opts ...SubscribeOption) (Subscriber, error) {
+func (m *memoryBroker) BatchSubscribe(ctx context.Context, topic string, handler BatchHandler, opts ...SubscribeOption) (Subscriber, error) {
 	m.RLock()
 	if !m.connected {
 		m.RUnlock()
-		return nil, errors.New("not connected")
+		return nil, ErrNotConnected
 	}
 	m.RUnlock()
 
-	options := NewSubscribeOptions(opts...)
-
-	id, err := uuid.NewRandom()
+	sid, err := id.New()
 	if err != nil {
 		return nil, err
 	}
 
+	options := NewSubscribeOptions(opts...)
+
+	sub := &memorySubscriber{
+		exit:         make(chan bool, 1),
+		id:           sid,
+		topic:        topic,
+		batchhandler: 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) Subscribe(ctx context.Context, topic string, handler Handler, opts ...SubscribeOption) (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:      id.String(),
+		id:      sid,
 		topic:   topic,
 		handler: handler,
 		opts:    options,
@@ -163,20 +258,20 @@ func (m *memoryBroker) Subscribe(ctx context.Context, topic string, handler Hand
 	}
 
 	m.Lock()
-	m.Subscribers[topic] = append(m.Subscribers[topic], sub)
+	m.subscribers[topic] = append(m.subscribers[topic], sub)
 	m.Unlock()
 
 	go func() {
 		<-sub.exit
 		m.Lock()
-		var newSubscribers []*memorySubscriber
-		for _, sb := range m.Subscribers[topic] {
+		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.subscribers[topic] = newSubscribers
 		m.Unlock()
 	}()
 
@@ -221,6 +316,10 @@ func (m *memoryEvent) Error() error {
 	return m.err
 }
 
+func (m *memoryEvent) SetError(err error) {
+	m.err = err
+}
+
 func (m *memorySubscriber) Options() SubscribeOptions {
 	return m.opts
 }
@@ -238,6 +337,6 @@ func (m *memorySubscriber) Unsubscribe(ctx context.Context) error {
 func NewBroker(opts ...Option) Broker {
 	return &memoryBroker{
 		opts:        NewOptions(opts...),
-		Subscribers: make(map[string][]*memorySubscriber),
+		subscribers: make(map[string][]*memorySubscriber),
 	}
 }

broker/memory_test.go

@@ -4,8 +4,56 @@ import (
 	"context"
 	"fmt"
 	"testing"
+
+	"github.com/unistack-org/micro/v3/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 Events) error {
+		return evts.Ack()
+	}
+
+	sub, err := b.BatchSubscribe(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 := &Message{
+			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.BatchPublish(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()
@@ -26,20 +74,27 @@ func TestMemoryBroker(t *testing.T) {
 		t.Fatalf("Unexpected error subscribing %v", err)
 	}
 
+	msgs := make([]*Message, 0, count)
 	for i := 0; i < count; i++ {
 		message := &Message{
 			Header: map[string]string{
-				"foo": "bar",
-				"id":  fmt.Sprintf("%d", i),
+				metadata.HeaderTopic: topic,
+				"foo":                "bar",
+				"id":                 fmt.Sprintf("%d", i),
 			},
-			Body: []byte(`hello world`),
+			Body: []byte(`"hello world"`),
 		}
+		msgs = append(msgs, message)
 
 		if err := b.Publish(ctx, topic, message); err != nil {
-			t.Fatalf("Unexpected error publishing %d", i)
+			t.Fatalf("Unexpected error publishing %d err: %v", i, err)
 		}
 	}
 
+	if err := b.BatchPublish(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)
 	}

broker/options.go

@@ -3,6 +3,7 @@ package broker
 import (
 	"context"
 	"crypto/tls"
+	"time"
 
 	"github.com/unistack-org/micro/v3/codec"
 	"github.com/unistack-org/micro/v3/logger"
@@ -29,6 +30,8 @@ type Options struct {
 	TLSConfig *tls.Config
 	// ErrorHandler used when broker can't unmarshal incoming message
 	ErrorHandler Handler
+	// BatchErrorHandler used when broker can't unmashal incoming messages
+	BatchErrorHandler BatchHandler
 	// Name holds the broker name
 	Name string
 	// Addrs holds the broker address
@@ -71,11 +74,9 @@ func NewPublishOptions(opts ...PublishOption) PublishOptions {
 	options := PublishOptions{
 		Context: context.Background(),
 	}
-
 	for _, o := range opts {
 		o(&options)
 	}
-
 	return options
 }
 
@@ -85,12 +86,18 @@ type SubscribeOptions struct {
 	Context context.Context
 	// ErrorHandler used when broker can't unmarshal incoming message
 	ErrorHandler Handler
+	// BatchErrorHandler used when broker can't unmashal incoming messages
+	BatchErrorHandler BatchHandler
 	// Group holds consumer group
 	Group 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
 	BodyOnly bool
+	// BatchSize flag specifies max batch size
+	BatchSize int
+	// BatchWait flag specifies max wait time for batch filling
+	BatchWait time.Duration
 }
 
 // Option func
@@ -113,23 +120,6 @@ func PublishContext(ctx context.Context) PublishOption {
 	}
 }
 
-// SubscribeOption func
-type SubscribeOption func(*SubscribeOptions)
-
-// NewSubscribeOptions creates new SubscribeOptions
-func NewSubscribeOptions(opts ...SubscribeOption) SubscribeOptions {
-	options := SubscribeOptions{
-		AutoAck: true,
-		Context: context.Background(),
-	}
-
-	for _, o := range opts {
-		o(&options)
-	}
-
-	return options
-}
-
 // Addrs sets the host addresses to be used by the broker
 func Addrs(addrs ...string) Option {
 	return func(o *Options) {
@@ -145,28 +135,6 @@ func Codec(c codec.Codec) Option {
 	}
 }
 
-// DisableAutoAck disables auto ack
-func DisableAutoAck() SubscribeOption {
-	return func(o *SubscribeOptions) {
-		o.AutoAck = false
-	}
-}
-
-// SubscribeAutoAck will disable 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
-	}
-}
-
 // ErrorHandler will catch all broker errors that cant be handled
 // in normal way, for example Codec errors
 func ErrorHandler(h Handler) Option {
@@ -175,6 +143,14 @@ func ErrorHandler(h Handler) Option {
 	}
 }
 
+// BatchErrorHandler will catch all broker errors that cant be handled
+// in normal way, for example Codec errors
+func BatchErrorHandler(h BatchHandler) Option {
+	return func(o *Options) {
+		o.BatchErrorHandler = h
+	}
+}
+
 // SubscribeErrorHandler will catch all broker errors that cant be handled
 // in normal way, for example Codec errors
 func SubscribeErrorHandler(h Handler) SubscribeOption {
@@ -183,6 +159,14 @@ func SubscribeErrorHandler(h Handler) SubscribeOption {
 	}
 }
 
+// SubscribeBatchErrorHandler will catch all broker errors that cant be handled
+// in normal way, for example Codec errors
+func SubscribeBatchErrorHandler(h BatchHandler) SubscribeOption {
+	return func(o *SubscribeOptions) {
+		o.BatchErrorHandler = h
+	}
+}
+
 // Queue sets the subscribers queue
 // Deprecated
 func Queue(name string) SubscribeOption {
@@ -246,3 +230,55 @@ func SubscribeContext(ctx context.Context) SubscribeOption {
 		o.Context = ctx
 	}
 }
+
+// DisableAutoAck disables auto ack
+// Deprecated
+func DisableAutoAck() SubscribeOption {
+	return func(o *SubscribeOptions) {
+		o.AutoAck = false
+	}
+}
+
+// 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 ...SubscribeOption) SubscribeOptions {
+	options := SubscribeOptions{
+		AutoAck: true,
+		Context: context.Background(),
+	}
+	for _, o := range opts {
+		o(&options)
+	}
+	return options
+}

client/client.go

@@ -40,6 +40,7 @@ type Client interface {
 	Call(ctx context.Context, req Request, rsp interface{}, opts ...CallOption) error
 	Stream(ctx context.Context, req Request, opts ...CallOption) (Stream, error)
 	Publish(ctx context.Context, msg Message, opts ...PublishOption) error
+	BatchPublish(ctx context.Context, msg []Message, opts ...PublishOption) error
 	String() string
 }
 

client/noop.go

@@ -173,7 +173,7 @@ func (n *noopClient) NewRequest(service, endpoint string, req interface{}, opts
 }
 
 func (n *noopClient) NewMessage(topic string, msg interface{}, opts ...MessageOption) Message {
-	options := NewMessageOptions(opts...)
+	options := NewMessageOptions(append([]MessageOption{MessageContentType(n.opts.ContentType)}, opts...)...)
 	return &noopMessage{topic: topic, payload: msg, opts: options}
 }
 
@@ -181,47 +181,59 @@ func (n *noopClient) Stream(ctx context.Context, req Request, opts ...CallOption
 	return &noopStream{}, nil
 }
 
-func (n *noopClient) Publish(ctx context.Context, p Message, opts ...PublishOption) error {
-	var body []byte
+func (n *noopClient) BatchPublish(ctx context.Context, ps []Message, opts ...PublishOption) error {
+	return n.publish(ctx, ps, opts...)
+}
 
+func (n *noopClient) Publish(ctx context.Context, p Message, opts ...PublishOption) error {
+	return n.publish(ctx, []Message{p}, opts...)
+}
+
+func (n *noopClient) publish(ctx context.Context, ps []Message, opts ...PublishOption) error {
 	options := NewPublishOptions(opts...)
 
-	md, ok := metadata.FromOutgoingContext(ctx)
-	if !ok {
-		md = metadata.New(0)
-	}
-	md["Content-Type"] = p.ContentType()
-	md["Micro-Topic"] = p.Topic()
+	msgs := make([]*broker.Message, 0, len(ps))
 
-	// passed in raw data
-	if d, ok := p.Payload().(*codec.Frame); ok {
-		body = d.Data
-	} else {
-		// use codec for payload
-		cf, err := n.newCodec(p.ContentType())
-		if err != nil {
-			return errors.InternalServerError("go.micro.client", err.Error())
+	for _, p := range ps {
+		md, ok := metadata.FromOutgoingContext(ctx)
+		if !ok {
+			md = metadata.New(0)
+		}
+		md[metadata.HeaderContentType] = p.ContentType()
+
+		topic := p.Topic()
+
+		// get the exchange
+		if len(options.Exchange) > 0 {
+			topic = options.Exchange
 		}
 
-		// set the body
-		b, err := cf.Marshal(p.Payload())
-		if err != nil {
-			return errors.InternalServerError("go.micro.client", err.Error())
+		md[metadata.HeaderTopic] = topic
+
+		var body []byte
+
+		// passed in raw data
+		if d, ok := p.Payload().(*codec.Frame); ok {
+			body = d.Data
+		} else {
+			// use codec for payload
+			cf, err := n.newCodec(p.ContentType())
+			if err != nil {
+				return errors.InternalServerError("go.micro.client", err.Error())
+			}
+
+			// set the body
+			b, err := cf.Marshal(p.Payload())
+			if err != nil {
+				return errors.InternalServerError("go.micro.client", err.Error())
+			}
+			body = b
 		}
-		body = b
+
+		msgs = append(msgs, &broker.Message{Header: md, Body: body})
 	}
 
-	topic := p.Topic()
-
-	// get the exchange
-	if len(options.Exchange) > 0 {
-		topic = options.Exchange
-	}
-
-	return n.opts.Broker.Publish(ctx, topic, &broker.Message{
-		Header: md,
-		Body:   body,
-	},
+	return n.opts.Broker.BatchPublish(ctx, msgs,
 		broker.PublishContext(options.Context),
 		broker.PublishBodyOnly(options.BodyOnly),
 	)

client/options.go

@@ -19,6 +19,8 @@ import (
 
 // Options holds client options
 type Options struct {
+	// Transport used for transfer messages
+	Transport transport.Transport
 	// Selector used to select needed address
 	Selector selector.Selector
 	// Logger used to log messages
@@ -29,18 +31,16 @@ type Options struct {
 	Broker broker.Broker
 	// Meter used for metrics
 	Meter meter.Meter
-	// Router used to get route
-	Router router.Router
-	// Transport used for transfer messages
-	Transport transport.Transport
 	// Context is used for external options
 	Context context.Context
-	// Lookup func used to get destination addr
-	Lookup LookupFunc
-	// Codecs map
-	Codecs map[string]codec.Codec
+	// 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
@@ -68,12 +68,12 @@ func NewCallOptions(opts ...CallOption) CallOptions {
 
 // CallOptions holds client call options
 type CallOptions struct {
-	// Router used for route
-	Router router.Router
 	// Selector selects addr
 	Selector selector.Selector
 	// Context used for deadline
 	Context context.Context
+	// Router used for route
+	Router router.Router
 	// Retry func used for retries
 	Retry RetryFunc
 	// Backoff func used for backoff when retry
@@ -82,22 +82,22 @@ type CallOptions struct {
 	Network string
 	// Content-Type
 	ContentType string
-	// CallWrappers call wrappers
-	CallWrappers []CallWrapper
-	// SelectOptions selector options
-	SelectOptions []selector.SelectOption
+	// AuthToken string
+	AuthToken string
 	// Address specifies static addr list
 	Address []string
-	// Retries specifies retries num
-	Retries int
+	// SelectOptions selector options
+	SelectOptions []selector.SelectOption
+	// CallWrappers call wrappers
+	CallWrappers []CallWrapper
 	// StreamTimeout stream timeout
 	StreamTimeout time.Duration
 	// RequestTimeout request timeout
 	RequestTimeout time.Duration
 	// DialTimeout dial timeout
 	DialTimeout time.Duration
-	// AuthToken flag
-	AuthToken bool
+	// Retries specifies retries num
+	Retries int
 }
 
 // Context pass context to client
@@ -118,12 +118,12 @@ func NewPublishOptions(opts ...PublishOption) PublishOptions {
 
 // PublishOptions holds publish options
 type PublishOptions struct {
-	// BodyOnly will publish only message body
-	BodyOnly bool
 	// Context used for external options
 	Context context.Context
 	// Exchange topic exchange name
 	Exchange string
+	// BodyOnly will publish only message body
+	BodyOnly bool
 }
 
 // NewMessageOptions creates message options struct
@@ -267,7 +267,7 @@ func Transport(t transport.Transport) Option {
 func Register(r register.Register) Option {
 	return func(o *Options) {
 		if o.Router != nil {
-			o.Router.Init(router.Register(r))
+			_ = o.Router.Init(router.Register(r))
 		}
 	}
 }
@@ -331,7 +331,7 @@ func TLSConfig(t *tls.Config) Option {
 		// already set. Required for Init call below.
 
 		// set the transport tls
-		o.Transport.Init(
+		_ = o.Transport.Init(
 			transport.TLSConfig(t),
 		)
 	}
@@ -373,19 +373,35 @@ func DialTimeout(d time.Duration) Option {
 }
 
 // WithExchange sets the exchange to route a message through
+// Deprecated
 func WithExchange(e string) PublishOption {
 	return func(o *PublishOptions) {
 		o.Exchange = e
 	}
 }
 
+// PublishExchange sets the exchange to route a message through
+func PublishExchange(e string) PublishOption {
+	return func(o *PublishOptions) {
+		o.Exchange = e
+	}
+}
+
 // WithBodyOnly publish only message body
+// DERECATED
 func WithBodyOnly(b bool) PublishOption {
 	return func(o *PublishOptions) {
 		o.BodyOnly = b
 	}
 }
 
+// PublishBodyOnly publish only message body
+func PublishBodyOnly(b bool) PublishOption {
+	return func(o *PublishOptions) {
+		o.BodyOnly = b
+	}
+}
+
 // PublishContext sets the context in publish options
 func PublishContext(ctx context.Context) PublishOption {
 	return func(o *PublishOptions) {
@@ -463,9 +479,9 @@ func WithDialTimeout(d time.Duration) CallOption {
 
 // WithAuthToken is a CallOption which overrides the
 // authorization header with the services own auth token
-func WithAuthToken() CallOption {
+func WithAuthToken(t string) CallOption {
 	return func(o *CallOptions) {
-		o.AuthToken = true
+		o.AuthToken = t
 	}
 }
 
@@ -498,12 +514,20 @@ func WithSelectOptions(sops ...selector.SelectOption) CallOption {
 }
 
 // WithMessageContentType sets the message content type
+// Deprecated
 func WithMessageContentType(ct string) MessageOption {
 	return func(o *MessageOptions) {
 		o.ContentType = ct
 	}
 }
 
+// MessageContentType sets the message content type
+func MessageContentType(ct string) MessageOption {
+	return func(o *MessageOptions) {
+		o.ContentType = ct
+	}
+}
+
 // StreamingRequest specifies that request is streaming
 func StreamingRequest(b bool) RequestOption {
 	return func(o *RequestOptions) {

codec/codec.go

@@ -25,7 +25,7 @@ var (
 
 var (
 	// DefaultMaxMsgSize specifies how much data codec can handle
-	DefaultMaxMsgSize int = 1024 * 1024 * 4 // 4Mb
+	DefaultMaxMsgSize = 1024 * 1024 * 4 // 4Mb
 	// DefaultCodec is the global default codec
 	DefaultCodec Codec = NewCodec()
 	// DefaultTagName specifies struct tag name to control codec Marshal/Unmarshal
@@ -41,11 +41,11 @@ type MessageType int
 // connection. ReadBody may be called with a nil argument to force the
 // body to be read and discarded.
 type Codec interface {
-	ReadHeader(io.Reader, *Message, MessageType) error
-	ReadBody(io.Reader, interface{}) error
-	Write(io.Writer, *Message, interface{}) error
-	Marshal(interface{}) ([]byte, error)
-	Unmarshal([]byte, interface{}) error
+	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
 }
 
@@ -58,7 +58,7 @@ type Message struct {
 	Method   string
 	Endpoint string
 	Error    string
-	Id       string
+	ID       string
 	Body     []byte
 	Type     MessageType
 }
@@ -67,3 +67,20 @@ type Message struct {
 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
+}

codec/context.go

@@ -0,0 +1,34 @@
+package codec
+
+import (
+	"context"
+)
+
+type codecKey struct{}
+
+// FromContext returns codec from context
+func FromContext(ctx context.Context) (Codec, bool) {
+	if ctx == nil {
+		return nil, false
+	}
+	c, ok := ctx.Value(codecKey{}).(Codec)
+	return c, ok
+}
+
+// NewContext put codec in context
+func NewContext(ctx context.Context, c Codec) context.Context {
+	if ctx == nil {
+		ctx = context.Background()
+	}
+	return context.WithValue(ctx, codecKey{}, 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)
+	}
+}

codec/frame.go

@@ -4,3 +4,31 @@ package codec
 type Frame struct {
 	Data []byte
 }
+
+func (m *Frame) MarshalJSON() ([]byte, error) {
+	return m.Data, nil
+}
+
+func (m *Frame) UnmarshalJSON(data []byte) error {
+	m.Data = data
+	return nil
+}
+
+func (m *Frame) ProtoMessage() {}
+
+func (m *Frame) Reset() {
+	*m = Frame{}
+}
+
+func (m *Frame) String() string {
+	return string(m.Data)
+}
+
+func (m *Frame) Marshal() ([]byte, error) {
+	return m.Data, nil
+}
+
+func (m *Frame) Unmarshal(data []byte) error {
+	m.Data = data
+	return nil
+}

codec/noop.go

@@ -5,7 +5,9 @@ import (
 	"io"
 )
 
-type noopCodec struct{}
+type noopCodec struct {
+	opts Options
+}
 
 func (c *noopCodec) ReadHeader(conn io.Reader, m *Message, t MessageType) error {
 	return nil
@@ -69,11 +71,11 @@ func (c *noopCodec) String() string {
 }
 
 // NewCodec returns new noop codec
-func NewCodec() Codec {
-	return &noopCodec{}
+func NewCodec(opts ...Option) Codec {
+	return &noopCodec{opts: NewOptions(opts...)}
 }
 
-func (c *noopCodec) Marshal(v interface{}) ([]byte, error) {
+func (c *noopCodec) Marshal(v interface{}, opts ...Option) ([]byte, error) {
 	if v == nil {
 		return nil, nil
 	}
@@ -96,7 +98,7 @@ func (c *noopCodec) Marshal(v interface{}) ([]byte, error) {
 	return json.Marshal(v)
 }
 
-func (c *noopCodec) Unmarshal(d []byte, v interface{}) error {
+func (c *noopCodec) Unmarshal(d []byte, v interface{}, opts ...Option) error {
 	if v == nil {
 		return nil
 	}

codec/options.go

@@ -1,6 +1,8 @@
 package codec
 
 import (
+	"context"
+
 	"github.com/unistack-org/micro/v3/logger"
 	"github.com/unistack-org/micro/v3/meter"
 	"github.com/unistack-org/micro/v3/tracer"
@@ -17,6 +19,10 @@ type Options struct {
 	Logger logger.Logger
 	// Tracer used for tracing
 	Tracer tracer.Tracer
+	// Context stores additional codec options
+	Context context.Context
+	// TagName specifies tag name in struct to control codec
+	TagName string
 	// MaxMsgSize specifies max messages size that reads by codec
 	MaxMsgSize int
 }
@@ -28,6 +34,13 @@ func MaxMsgSize(n int) Option {
 	}
 }
 
+// TagName sets the codec tag name in struct
+func TagName(n string) Option {
+	return func(o *Options) {
+		o.TagName = n
+	}
+}
+
 // Logger sets the logger
 func Logger(l logger.Logger) Option {
 	return func(o *Options) {
@@ -52,10 +65,12 @@ func Meter(m meter.Meter) Option {
 // NewOptions returns new options
 func NewOptions(opts ...Option) Options {
 	options := Options{
+		Context:    context.Background(),
 		Logger:     logger.DefaultLogger,
 		Meter:      meter.DefaultMeter,
 		Tracer:     tracer.DefaultTracer,
 		MaxMsgSize: DefaultMaxMsgSize,
+		TagName:    DefaultTagName,
 	}
 
 	for _, o := range opts {

config/config.go

@@ -4,11 +4,18 @@ package config
 import (
 	"context"
 	"errors"
+	"time"
 )
 
 // DefaultConfig default config
 var DefaultConfig Config = NewConfig()
 
+// DefaultWatcherMinInterval default min interval for poll changes
+var DefaultWatcherMinInterval = 5 * time.Second
+
+// DefaultWatcherMaxInterval default max interval for poll changes
+var DefaultWatcherMaxInterval = 9 * time.Second
+
 var (
 	// ErrCodecMissing is returned when codec needed and not specified
 	ErrCodecMissing = errors.New("codec missing")
@@ -30,28 +37,80 @@ type Config interface {
 	Load(context.Context, ...LoadOption) error
 	// Save config to sources
 	Save(context.Context, ...SaveOption) error
-	// Watch a value for changes
-	//Watch(context.Context) (Watcher, error)
+	// Watch a config for changes
+	Watch(context.Context, ...WatchOption) (Watcher, error)
 	// String returns config type name
 	String() string
 }
 
 // Watcher is the config watcher
 type Watcher interface {
-	// Next() (, error)
+	// Next blocks until update happens or error returned
+	Next() (map[string]interface{}, error)
+	// Stop stops watcher
 	Stop() error
 }
 
 // Load loads config from config sources
-func Load(ctx context.Context, cs ...Config) error {
+func Load(ctx context.Context, cs []Config, opts ...LoadOption) error {
 	var err error
 	for _, c := range cs {
 		if err = c.Init(); err != nil {
 			return err
 		}
-		if err = c.Load(ctx); err != nil {
+		if err = c.Load(ctx, opts...); err != nil {
 			return err
 		}
 	}
 	return nil
 }
+
+var (
+	DefaultAfterLoad = func(ctx context.Context, c Config) error {
+		for _, fn := range c.Options().AfterLoad {
+			if err := fn(ctx, c); err != nil {
+				c.Options().Logger.Errorf(ctx, "%s AfterLoad err: %v", c.String(), err)
+				if !c.Options().AllowFail {
+					return err
+				}
+			}
+		}
+		return nil
+	}
+
+	DefaultAfterSave = func(ctx context.Context, c Config) error {
+		for _, fn := range c.Options().AfterSave {
+			if err := fn(ctx, c); err != nil {
+				c.Options().Logger.Errorf(ctx, "%s AfterSave err: %v", c.String(), err)
+				if !c.Options().AllowFail {
+					return err
+				}
+			}
+		}
+		return nil
+	}
+
+	DefaultBeforeLoad = func(ctx context.Context, c Config) error {
+		for _, fn := range c.Options().BeforeLoad {
+			if err := fn(ctx, c); err != nil {
+				c.Options().Logger.Errorf(ctx, "%s BeforeLoad err: %v", c.String(), err)
+				if !c.Options().AllowFail {
+					return err
+				}
+			}
+		}
+		return nil
+	}
+
+	DefaultBeforeSave = func(ctx context.Context, c Config) error {
+		for _, fn := range c.Options().BeforeSave {
+			if err := fn(ctx, c); err != nil {
+				c.Options().Logger.Errorf(ctx, "%s BeforeSavec err: %v", c.String(), err)
+				if !c.Options().AllowFail {
+					return err
+				}
+			}
+		}
+		return nil
+	}
+)

config/default.go

@@ -2,6 +2,7 @@ package config
 
 import (
 	"context"
+	"fmt"
 	"reflect"
 	"strconv"
 	"strings"
@@ -26,10 +27,8 @@ func (c *defaultConfig) Init(opts ...Option) error {
 }
 
 func (c *defaultConfig) Load(ctx context.Context, opts ...LoadOption) error {
-	for _, fn := range c.opts.BeforeLoad {
-		if err := fn(ctx, c); err != nil && !c.opts.AllowFail {
-			return err
-		}
+	if err := DefaultBeforeLoad(ctx, c); err != nil {
+		return err
 	}
 
 	options := NewLoadOptions(opts...)
@@ -41,29 +40,39 @@ func (c *defaultConfig) Load(ctx context.Context, opts ...LoadOption) error {
 		mopts = append(mopts, mergo.WithAppendSlice)
 	}
 
-	src, err := rutil.Zero(c.opts.Struct)
-	if err == nil {
-		valueOf := reflect.ValueOf(src)
-		if err = c.fillValues(valueOf); err == nil {
-			err = mergo.Merge(c.opts.Struct, src, mopts...)
-		}
+	dst := c.opts.Struct
+	if options.Struct != nil {
+		dst = options.Struct
 	}
 
-	if err != nil && !c.opts.AllowFail {
-		return err
-	}
-
-	for _, fn := range c.opts.AfterLoad {
-		if err := fn(ctx, c); err != nil && !c.opts.AllowFail {
+	src, err := rutil.Zero(dst)
+	if err != nil {
+		if !c.opts.AllowFail {
 			return err
 		}
+		return DefaultAfterLoad(ctx, c)
+	}
+
+	if err = fillValues(reflect.ValueOf(src), c.opts.StructTag); err == nil {
+		err = mergo.Merge(dst, src, mopts...)
+	}
+
+	if err != nil {
+		c.opts.Logger.Errorf(ctx, "default load error: %v", err)
+		if !c.opts.AllowFail {
+			return err
+		}
+	}
+
+	if err := DefaultAfterLoad(ctx, c); err != nil {
+		return err
 	}
 
 	return nil
 }
 
 //nolint:gocyclo
-func (c *defaultConfig) fillValue(value reflect.Value, val string) error {
+func fillValue(value reflect.Value, val string) error {
 	if !rutil.IsEmpty(value) {
 		return nil
 	}
@@ -80,10 +89,10 @@ func (c *defaultConfig) fillValue(value reflect.Value, val string) error {
 			kv := strings.FieldsFunc(nval, func(c rune) bool { return c == '=' })
 			mkey := reflect.Indirect(reflect.New(kt))
 			mval := reflect.Indirect(reflect.New(et))
-			if err := c.fillValue(mkey, kv[0]); err != nil {
+			if err := fillValue(mkey, kv[0]); err != nil {
 				return err
 			}
-			if err := c.fillValue(mval, kv[1]); err != nil {
+			if err := fillValue(mval, kv[1]); err != nil {
 				return err
 			}
 			value.SetMapIndex(mkey, mval)
@@ -93,7 +102,7 @@ func (c *defaultConfig) fillValue(value reflect.Value, val string) error {
 		value.Set(reflect.MakeSlice(reflect.SliceOf(value.Type().Elem()), len(nvals), len(nvals)))
 		for idx, nval := range nvals {
 			nvalue := reflect.Indirect(reflect.New(value.Type().Elem()))
-			if err := c.fillValue(nvalue, nval); err != nil {
+			if err := fillValue(nvalue, nval); err != nil {
 				return err
 			}
 			value.Index(idx).Set(nvalue)
@@ -182,7 +191,7 @@ func (c *defaultConfig) fillValue(value reflect.Value, val string) error {
 	return nil
 }
 
-func (c *defaultConfig) fillValues(valueOf reflect.Value) error {
+func fillValues(valueOf reflect.Value, tname string) error {
 	var values reflect.Value
 
 	if valueOf.Kind() == reflect.Ptr {
@@ -209,7 +218,7 @@ func (c *defaultConfig) fillValues(valueOf reflect.Value) error {
 		switch value.Kind() {
 		case reflect.Struct:
 			value.Set(reflect.Indirect(reflect.New(value.Type())))
-			if err := c.fillValues(value); err != nil {
+			if err := fillValues(value, tname); err != nil {
 				return err
 			}
 			continue
@@ -223,17 +232,17 @@ func (c *defaultConfig) fillValues(valueOf reflect.Value) error {
 				value.Set(reflect.New(value.Type().Elem()))
 			}
 			value = value.Elem()
-			if err := c.fillValues(value); err != nil {
+			if err := fillValues(value, tname); err != nil {
 				return err
 			}
 			continue
 		}
-		tag, ok := field.Tag.Lookup(c.opts.StructTag)
+		tag, ok := field.Tag.Lookup(tname)
 		if !ok {
 			continue
 		}
 
-		if err := c.fillValue(value, tag); err != nil {
+		if err := fillValue(value, tag); err != nil {
 			return err
 		}
 	}
@@ -242,16 +251,12 @@ func (c *defaultConfig) fillValues(valueOf reflect.Value) error {
 }
 
 func (c *defaultConfig) Save(ctx context.Context, opts ...SaveOption) error {
-	for _, fn := range c.opts.BeforeSave {
-		if err := fn(ctx, c); err != nil && !c.opts.AllowFail {
-			return err
-		}
+	if err := DefaultBeforeSave(ctx, c); err != nil {
+		return err
 	}
 
-	for _, fn := range c.opts.AfterSave {
-		if err := fn(ctx, c); err != nil && !c.opts.AllowFail {
-			return err
-		}
+	if err := DefaultAfterSave(ctx, c); err != nil {
+		return err
 	}
 
 	return nil
@@ -265,6 +270,10 @@ func (c *defaultConfig) Name() string {
 	return c.opts.Name
 }
 
+func (c *defaultConfig) Watch(ctx context.Context, opts ...WatchOption) (Watcher, error) {
+	return nil, fmt.Errorf("not implemented")
+}
+
 // NewConfig returns new default config source
 func NewConfig(opts ...Option) Config {
 	options := NewOptions(opts...)

config/default_test.go

@@ -47,6 +47,6 @@ func TestDefault(t *testing.T) {
 	if conf.StringValue != "after_load" {
 		t.Fatal("AfterLoad option not working")
 	}
-
-	t.Logf("%#+v\n", conf)
+	_ = conf
+	// t.Logf("%#+v\n", conf)
 }

config/options.go

@@ -2,6 +2,7 @@ package config
 
 import (
 	"context"
+	"time"
 
 	"github.com/unistack-org/micro/v3/codec"
 	"github.com/unistack-org/micro/v3/logger"
@@ -62,6 +63,7 @@ type LoadOption func(o *LoadOptions)
 
 // LoadOptions struct
 type LoadOptions struct {
+	Struct   interface{}
 	Override bool
 	Append   bool
 }
@@ -88,13 +90,29 @@ func LoadAppend(b bool) LoadOption {
 	}
 }
 
+// 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{}
 }
 
+// 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 ...SaveOption) SaveOptions {
 	options := SaveOptions{}
 	for _, o := range opts {
@@ -186,3 +204,60 @@ func Name(n string) Option {
 		o.Name = n
 	}
 }
+
+// WatchOptions struuct
+type WatchOptions struct {
+	// Context used by non default options
+	Context context.Context
+	// Struct for filling
+	Struct interface{}
+	// MinInterval specifies the min time.Duration interval for poll changes
+	MinInterval time.Duration
+	// MaxInterval specifies the max time.Duration interval for poll changes
+	MaxInterval time.Duration
+	// Coalesce multiple events to one
+	Coalesce bool
+}
+
+type WatchOption func(*WatchOptions)
+
+func NewWatchOptions(opts ...WatchOption) WatchOptions {
+	options := WatchOptions{
+		Context:     context.Background(),
+		MinInterval: DefaultWatcherMinInterval,
+		MaxInterval: DefaultWatcherMaxInterval,
+	}
+	for _, o := range opts {
+		o(&options)
+	}
+	return options
+}
+
+// WatchContext pass context
+func WatchContext(ctx context.Context) WatchOption {
+	return func(o *WatchOptions) {
+		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) WatchOption {
+	return func(o *WatchOptions) {
+		o.MinInterval = min
+		o.MaxInterval = max
+	}
+}
+
+// WatchStruct overrides struct for fill
+func WatchStruct(src interface{}) WatchOption {
+	return func(o *WatchOptions) {
+		o.Struct = src
+	}
+}

config/reflect_test.go

@@ -1,26 +0,0 @@
-package config_test
-
-import (
-	"testing"
-
-	rutil "github.com/unistack-org/micro/v3/util/reflect"
-)
-
-type Config struct {
-	SubConfig *SubConfig
-	Config    *Config
-	Value     string
-}
-
-type SubConfig struct {
-	Value string
-}
-
-func TestReflect(t *testing.T) {
-	cfg1 := &Config{Value: "cfg1", Config: &Config{Value: "cfg1_1"}, SubConfig: &SubConfig{Value: "cfg1"}}
-	cfg2, err := rutil.Zero(cfg1)
-	if err != nil {
-		t.Fatal(err)
-	}
-	t.Logf("dst: %#+v\n", cfg2)
-}

errors/errors.go

@@ -37,8 +37,8 @@ var (
 
 // Error type
 type Error struct {
-	// Id holds error id or service, usually someting like my_service or uuid
-	Id string
+	// ID holds error id or service, usually someting like my_service or id
+	ID string
 	// Detail holds some useful details about error
 	Detail string
 	// Status usually holds text of http status
@@ -56,7 +56,7 @@ func (e *Error) Error() string {
 // New generates a custom error
 func New(id, detail string, code int32) error {
 	return &Error{
-		Id:     id,
+		ID:     id,
 		Code:   code,
 		Detail: detail,
 		Status: http.StatusText(int(code)),
@@ -77,7 +77,7 @@ func Parse(err string) *Error {
 // BadRequest generates a 400 error.
 func BadRequest(id, format string, a ...interface{}) error {
 	return &Error{
-		Id:     id,
+		ID:     id,
 		Code:   400,
 		Detail: fmt.Sprintf(format, a...),
 		Status: http.StatusText(400),
@@ -87,7 +87,7 @@ func BadRequest(id, format string, a ...interface{}) error {
 // Unauthorized generates a 401 error.
 func Unauthorized(id, format string, a ...interface{}) error {
 	return &Error{
-		Id:     id,
+		ID:     id,
 		Code:   401,
 		Detail: fmt.Sprintf(format, a...),
 		Status: http.StatusText(401),
@@ -97,7 +97,7 @@ func Unauthorized(id, format string, a ...interface{}) error {
 // Forbidden generates a 403 error.
 func Forbidden(id, format string, a ...interface{}) error {
 	return &Error{
-		Id:     id,
+		ID:     id,
 		Code:   403,
 		Detail: fmt.Sprintf(format, a...),
 		Status: http.StatusText(403),
@@ -107,7 +107,7 @@ func Forbidden(id, format string, a ...interface{}) error {
 // NotFound generates a 404 error.
 func NotFound(id, format string, a ...interface{}) error {
 	return &Error{
-		Id:     id,
+		ID:     id,
 		Code:   404,
 		Detail: fmt.Sprintf(format, a...),
 		Status: http.StatusText(404),
@@ -117,7 +117,7 @@ func NotFound(id, format string, a ...interface{}) error {
 // MethodNotAllowed generates a 405 error.
 func MethodNotAllowed(id, format string, a ...interface{}) error {
 	return &Error{
-		Id:     id,
+		ID:     id,
 		Code:   405,
 		Detail: fmt.Sprintf(format, a...),
 		Status: http.StatusText(405),
@@ -127,7 +127,7 @@ func MethodNotAllowed(id, format string, a ...interface{}) error {
 // Timeout generates a 408 error.
 func Timeout(id, format string, a ...interface{}) error {
 	return &Error{
-		Id:     id,
+		ID:     id,
 		Code:   408,
 		Detail: fmt.Sprintf(format, a...),
 		Status: http.StatusText(408),
@@ -137,7 +137,7 @@ func Timeout(id, format string, a ...interface{}) error {
 // Conflict generates a 409 error.
 func Conflict(id, format string, a ...interface{}) error {
 	return &Error{
-		Id:     id,
+		ID:     id,
 		Code:   409,
 		Detail: fmt.Sprintf(format, a...),
 		Status: http.StatusText(409),
@@ -147,7 +147,7 @@ func Conflict(id, format string, a ...interface{}) error {
 // InternalServerError generates a 500 error.
 func InternalServerError(id, format string, a ...interface{}) error {
 	return &Error{
-		Id:     id,
+		ID:     id,
 		Code:   500,
 		Detail: fmt.Sprintf(format, a...),
 		Status: http.StatusText(500),
@@ -157,7 +157,7 @@ func InternalServerError(id, format string, a ...interface{}) error {
 // NotImplemented generates a 501 error
 func NotImplemented(id, format string, a ...interface{}) error {
 	return &Error{
-		Id:     id,
+		ID:     id,
 		Code:   501,
 		Detail: fmt.Sprintf(format, a...),
 		Status: http.StatusText(501),
@@ -167,7 +167,7 @@ func NotImplemented(id, format string, a ...interface{}) error {
 // BadGateway generates a 502 error
 func BadGateway(id, format string, a ...interface{}) error {
 	return &Error{
-		Id:     id,
+		ID:     id,
 		Code:   502,
 		Detail: fmt.Sprintf(format, a...),
 		Status: http.StatusText(502),
@@ -177,7 +177,7 @@ func BadGateway(id, format string, a ...interface{}) error {
 // ServiceUnavailable generates a 503 error
 func ServiceUnavailable(id, format string, a ...interface{}) error {
 	return &Error{
-		Id:     id,
+		ID:     id,
 		Code:   503,
 		Detail: fmt.Sprintf(format, a...),
 		Status: http.StatusText(503),
@@ -187,7 +187,7 @@ func ServiceUnavailable(id, format string, a ...interface{}) error {
 // GatewayTimeout generates a 504 error
 func GatewayTimeout(id, format string, a ...interface{}) error {
 	return &Error{
-		Id:     id,
+		ID:     id,
 		Code:   504,
 		Detail: fmt.Sprintf(format, a...),
 		Status: http.StatusText(504),

errors/errors_test.go

@@ -9,12 +9,12 @@ import (
 func TestFromError(t *testing.T) {
 	err := NotFound("go.micro.test", "%s", "example")
 	merr := FromError(err)
-	if merr.Id != "go.micro.test" || merr.Code != 404 {
+	if merr.ID != "go.micro.test" || merr.Code != 404 {
 		t.Fatalf("invalid conversation %v != %v", err, merr)
 	}
 	err = er.New(err.Error())
 	merr = FromError(err)
-	if merr.Id != "go.micro.test" || merr.Code != 404 {
+	if merr.ID != "go.micro.test" || merr.Code != 404 {
 		t.Fatalf("invalid conversation %v != %v", err, merr)
 	}
 }
@@ -36,7 +36,7 @@ func TestEqual(t *testing.T) {
 func TestErrors(t *testing.T) {
 	testData := []*Error{
 		{
-			Id:     "test",
+			ID:     "test",
 			Code:   500,
 			Detail: "Internal server error",
 			Status: http.StatusText(500),
@@ -44,7 +44,7 @@ func TestErrors(t *testing.T) {
 	}
 
 	for _, e := range testData {
-		ne := New(e.Id, e.Detail, e.Code)
+		ne := New(e.ID, e.Detail, e.Code)
 
 		if e.Error() != ne.Error() {
 			t.Fatalf("Expected %s got %s", e.Error(), ne.Error())
@@ -56,8 +56,8 @@ func TestErrors(t *testing.T) {
 			t.Fatalf("Expected error got nil %v", pe)
 		}
 
-		if pe.Id != e.Id {
-			t.Fatalf("Expected %s got %s", e.Id, pe.Id)
+		if pe.ID != e.ID {
+			t.Fatalf("Expected %s got %s", e.ID, pe.ID)
 		}
 
 		if pe.Detail != e.Detail {

flow/context.go

@@ -0,0 +1,34 @@
+package flow
+
+import (
+	"context"
+)
+
+type flowKey struct{}
+
+// FromContext returns Flow from context
+func FromContext(ctx context.Context) (Flow, bool) {
+	if ctx == nil {
+		return nil, false
+	}
+	c, ok := ctx.Value(flowKey{}).(Flow)
+	return c, ok
+}
+
+// NewContext stores Flow to context
+func NewContext(ctx context.Context, f Flow) context.Context {
+	if ctx == nil {
+		ctx = context.Background()
+	}
+	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/default.go

@@ -0,0 +1,585 @@
+package flow
+
+import (
+	"context"
+	"fmt"
+	"path/filepath"
+	"sync"
+
+	"github.com/silas/dag"
+	"github.com/unistack-org/micro/v3/client"
+	"github.com/unistack-org/micro/v3/codec"
+	"github.com/unistack-org/micro/v3/logger"
+	"github.com/unistack-org/micro/v3/metadata"
+	"github.com/unistack-org/micro/v3/store"
+	"github.com/unistack-org/micro/v3/util/id"
+)
+
+type microFlow struct {
+	opts Options
+}
+
+type microWorkflow struct {
+	opts   Options
+	g      *dag.AcyclicGraph
+	steps  map[string]Step
+	id     string
+	status Status
+	sync.RWMutex
+	init bool
+}
+
+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 {
+	w.Lock()
+
+	for _, s := range steps {
+		w.steps[s.String()] = s
+		w.g.Add(s)
+	}
+
+	for _, dst := range steps {
+		for _, req := range dst.Requires() {
+			src, ok := w.steps[req]
+			if !ok {
+				return ErrStepNotExists
+			}
+			w.g.Connect(dag.BasicEdge(src, dst))
+		}
+	}
+
+	if err := w.g.Validate(); err != nil {
+		w.Unlock()
+		return err
+	}
+
+	w.g.TransitiveReduction()
+
+	w.Unlock()
+
+	return nil
+}
+
+func (w *microWorkflow) RemoveSteps(steps ...Step) error {
+	// TODO: handle case when some step requires or required by removed step
+
+	w.Lock()
+
+	for _, s := range steps {
+		delete(w.steps, s.String())
+		w.g.Remove(s)
+	}
+
+	for _, dst := range steps {
+		for _, req := range dst.Requires() {
+			src, ok := w.steps[req]
+			if !ok {
+				return ErrStepNotExists
+			}
+			w.g.Connect(dag.BasicEdge(src, dst))
+		}
+	}
+
+	if err := w.g.Validate(); err != nil {
+		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, 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, 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, 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 ...ExecuteOption) (string, error) {
+	w.Lock()
+	if !w.init {
+		if err := w.g.Validate(); err != nil {
+			w.Unlock()
+			return "", err
+		}
+		w.g.TransitiveReduction()
+		w.init = true
+	}
+	w.Unlock()
+
+	eid, err := id.New()
+	if err != nil {
+		return "", err
+	}
+
+	stepStore := store.NewNamespaceStore(w.opts.Store, filepath.Join("steps", eid))
+	workflowStore := store.NewNamespaceStore(w.opts.Store, filepath.Join("workflows", eid))
+
+	options := NewExecuteOptions(opts...)
+
+	steps, err := w.getSteps(options.Start, options.Reverse)
+	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([]ExecuteOption, 0, len(opts)+5)
+
+	nopts = append(nopts,
+		ExecuteClient(w.opts.Client),
+		ExecuteTracer(w.opts.Tracer),
+		ExecuteLogger(w.opts.Logger),
+		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 {
+		w.opts.Logger.Errorf(w.opts.Context, "store error: %v", werr)
+		return eid, werr
+	}
+	for idx := range steps {
+		for nidx := range steps[idx] {
+			cstep := steps[idx][nidx]
+			if werr := stepStore.Write(ctx, filepath.Join(cstep.ID(), "status"), &codec.Frame{Data: []byte(StatusPending.String())}); werr != nil {
+				return eid, werr
+			}
+		}
+	}
+
+	go func() {
+		for idx := range steps {
+			for nidx := range steps[idx] {
+				wStatus := &codec.Frame{}
+				if werr := workflowStore.Read(w.opts.Context, "status", wStatus); werr != nil {
+					cherr <- werr
+					return
+				}
+				if status := StringStatus[string(wStatus.Data)]; status != StatusRunning {
+					chstatus <- status
+					return
+				}
+				if w.opts.Logger.V(logger.TraceLevel) {
+					w.opts.Logger.Tracef(nctx, "will be executed %v", steps[idx][nidx])
+				}
+				cstep := steps[idx][nidx]
+				// nolint: nestif
+				if len(cstep.Requires()) == 0 {
+					wg.Add(1)
+					go func(step Step) {
+						defer wg.Done()
+						if werr := stepStore.Write(ctx, filepath.Join(step.ID(), "req"), req); werr != nil {
+							cherr <- werr
+							return
+						}
+						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, 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, 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, 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, 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
+						}
+					}(cstep)
+					wg.Wait()
+				} else {
+					if werr := stepStore.Write(ctx, filepath.Join(cstep.ID(), "req"), req); werr != nil {
+						cherr <- werr
+						return
+					}
+					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, 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, 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, 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, filepath.Join(cstep.ID(), "status"), &codec.Frame{Data: []byte(StatusSuccess.String())}); werr != nil {
+						cherr <- werr
+						return
+					}
+				}
+			}
+		}
+		close(done)
+	}()
+
+	if options.Async {
+		return eid, nil
+	}
+
+	logger.Tracef(ctx, "wait for finish or error")
+	select {
+	case <-nctx.Done():
+		err = nctx.Err()
+	case cerr := <-cherr:
+		err = cerr
+	case <-done:
+		close(cherr)
+	case <-chstatus:
+		close(chstatus)
+		return eid, nil
+	}
+
+	switch {
+	case nctx.Err() != nil:
+		if werr := workflowStore.Write(w.opts.Context, "status", &codec.Frame{Data: []byte(StatusAborted.String())}); werr != nil {
+			w.opts.Logger.Errorf(w.opts.Context, "store error: %v", werr)
+		}
+	case err == nil:
+		if werr := workflowStore.Write(w.opts.Context, "status", &codec.Frame{Data: []byte(StatusSuccess.String())}); werr != nil {
+			w.opts.Logger.Errorf(w.opts.Context, "store error: %v", werr)
+		}
+	case err != nil:
+		if werr := workflowStore.Write(w.opts.Context, "status", &codec.Frame{Data: []byte(StatusFailure.String())}); werr != nil {
+			w.opts.Logger.Errorf(w.opts.Context, "store error: %v", werr)
+		}
+	}
+
+	return eid, err
+}
+
+func NewFlow(opts ...Option) Flow {
+	options := NewOptions(opts...)
+	return &microFlow{opts: options}
+}
+
+func (f *microFlow) Options() Options {
+	return f.opts
+}
+
+func (f *microFlow) Init(opts ...Option) error {
+	for _, o := range opts {
+		o(&f.opts)
+	}
+	if err := f.opts.Client.Init(); err != nil {
+		return err
+	}
+	if err := f.opts.Tracer.Init(); err != nil {
+		return err
+	}
+	if err := f.opts.Logger.Init(); err != nil {
+		return err
+	}
+	if err := f.opts.Meter.Init(); err != nil {
+		return err
+	}
+	if err := f.opts.Store.Init(); err != nil {
+		return err
+	}
+	return nil
+}
+
+func (f *microFlow) WorkflowList(ctx context.Context) ([]Workflow, error) {
+	return nil, nil
+}
+
+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))}
+
+	for _, s := range steps {
+		w.steps[s.String()] = s
+		w.g.Add(s)
+	}
+
+	for _, dst := range steps {
+		for _, req := range dst.Requires() {
+			src, ok := w.steps[req]
+			if !ok {
+				return nil, ErrStepNotExists
+			}
+			w.g.Connect(dag.BasicEdge(src, dst))
+		}
+	}
+
+	if err := w.g.Validate(); err != nil {
+		return nil, err
+	}
+	w.g.TransitiveReduction()
+
+	w.init = true
+
+	return w, nil
+}
+
+func (f *microFlow) WorkflowRemove(ctx context.Context, id string) error {
+	return nil
+}
+
+func (f *microFlow) WorkflowSave(ctx context.Context, w Workflow) error {
+	return nil
+}
+
+func (f *microFlow) WorkflowLoad(ctx context.Context, id string) (Workflow, error) {
+	return nil, nil
+}
+
+type microCallStep struct {
+	rsp     *Message
+	req     *Message
+	service string
+	method  string
+	opts    StepOptions
+	status  Status
+}
+
+func (s *microCallStep) Request() *Message {
+	return s.req
+}
+
+func (s *microCallStep) Response() *Message {
+	return s.rsp
+}
+
+func (s *microCallStep) ID() string {
+	return s.String()
+}
+
+func (s *microCallStep) Options() StepOptions {
+	return s.opts
+}
+
+func (s *microCallStep) Endpoint() string {
+	return s.method
+}
+
+func (s *microCallStep) Requires() []string {
+	return s.opts.Requires
+}
+
+func (s *microCallStep) Require(steps ...Step) error {
+	for _, step := range steps {
+		s.opts.Requires = append(s.opts.Requires, step.String())
+	}
+	return nil
+}
+
+func (s *microCallStep) String() string {
+	if s.opts.ID != "" {
+		return s.opts.ID
+	}
+	return fmt.Sprintf("%s.%s", s.service, s.method)
+}
+
+func (s *microCallStep) Name() string {
+	return s.String()
+}
+
+func (s *microCallStep) Hashcode() interface{} {
+	return s.String()
+}
+
+func (s *microCallStep) GetStatus() Status {
+	return s.status
+}
+
+func (s *microCallStep) SetStatus(status Status) {
+	s.status = status
+}
+
+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 := []client.CallOption{client.WithRetries(0)}
+	if options.Timeout > 0 {
+		copts = append(copts,
+			client.WithRequestTimeout(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...)
+	if err != nil {
+		return nil, err
+	}
+	md, _ := metadata.FromOutgoingContext(nctx)
+	return &Message{Header: md, Body: rsp.Data}, err
+}
+
+type microPublishStep struct {
+	req    *Message
+	rsp    *Message
+	topic  string
+	opts   StepOptions
+	status Status
+}
+
+func (s *microPublishStep) Request() *Message {
+	return s.req
+}
+
+func (s *microPublishStep) Response() *Message {
+	return s.rsp
+}
+
+func (s *microPublishStep) ID() string {
+	return s.String()
+}
+
+func (s *microPublishStep) Options() StepOptions {
+	return s.opts
+}
+
+func (s *microPublishStep) Endpoint() string {
+	return s.topic
+}
+
+func (s *microPublishStep) Requires() []string {
+	return s.opts.Requires
+}
+
+func (s *microPublishStep) Require(steps ...Step) error {
+	for _, step := range steps {
+		s.opts.Requires = append(s.opts.Requires, step.String())
+	}
+	return nil
+}
+
+func (s *microPublishStep) String() string {
+	if s.opts.ID != "" {
+		return s.opts.ID
+	}
+	return s.topic
+}
+
+func (s *microPublishStep) Name() string {
+	return s.String()
+}
+
+func (s *microPublishStep) Hashcode() interface{} {
+	return s.String()
+}
+
+func (s *microPublishStep) GetStatus() Status {
+	return s.status
+}
+
+func (s *microPublishStep) SetStatus(status Status) {
+	s.status = status
+}
+
+func (s *microPublishStep) Execute(ctx context.Context, req *Message, opts ...ExecuteOption) (*Message, error) {
+	return nil, nil
+}
+
+func NewCallStep(service string, name string, method string, opts ...StepOption) Step {
+	options := NewStepOptions(opts...)
+	return &microCallStep{service: service, method: name + "." + method, opts: options}
+}
+
+func NewPublishStep(topic string, opts ...StepOption) Step {
+	options := NewStepOptions(opts...)
+	return &microPublishStep{topic: topic, opts: options}
+}

flow/flow.go

@@ -1,17 +1,152 @@
 // Package flow is an interface used for saga pattern microservice workflow
 package flow
 
+import (
+	"context"
+	"errors"
+	"sync"
+	"sync/atomic"
+
+	"github.com/unistack-org/micro/v3/metadata"
+)
+
+var (
+	ErrStepNotExists = errors.New("step not exists")
+	ErrMissingClient = errors.New("client not set")
+)
+
+// RawMessage is a raw encoded JSON value.
+// It implements Marshaler and Unmarshaler and can be used to delay decoding or precompute a encoding.
+type RawMessage []byte
+
+// MarshalJSON returns m as the JSON encoding of m.
+func (m *RawMessage) MarshalJSON() ([]byte, error) {
+	if m == nil {
+		return []byte("null"), nil
+	}
+	return *m, nil
+}
+
+// UnmarshalJSON sets *m to a copy of data.
+func (m *RawMessage) UnmarshalJSON(data []byte) error {
+	if m == nil {
+		return errors.New("RawMessage UnmarshalJSON on nil pointer")
+	}
+	*m = append((*m)[0:0], data...)
+	return nil
+}
+
+type Message struct {
+	Header metadata.Metadata
+	Body   RawMessage
+}
+
+// Step represents dedicated workflow step
 type Step interface {
+	// ID returns step id
+	ID() string
 	// Endpoint returns rpc endpoint service_name.service_method or broker topic
 	Endpoint() string
+	// Execute step run
+	Execute(ctx context.Context, req *Message, opts ...ExecuteOption) (*Message, error)
+	// Requires returns dependent steps
+	Requires() []string
+	// Options returns step options
+	Options() StepOptions
+	// Require add required steps
+	Require(steps ...Step) error
+	// String
+	String() string
+	// GetStatus returns step status
+	GetStatus() Status
+	// SetStatus sets the step status
+	SetStatus(Status)
+	// Request returns step request message
+	Request() *Message
+	// Response returns step response message
+	Response() *Message
 }
 
+type Status int
+
+func (status Status) String() string {
+	return StatusString[status]
+}
+
+const (
+	StatusPending Status = iota
+	StatusRunning
+	StatusFailure
+	StatusSuccess
+	StatusAborted
+	StatusSuspend
+)
+
+var (
+	StatusString = map[Status]string{
+		StatusPending: "StatusPending",
+		StatusRunning: "StatusRunning",
+		StatusFailure: "StatusFailure",
+		StatusSuccess: "StatusSuccess",
+		StatusAborted: "StatusAborted",
+		StatusSuspend: "StatusSuspend",
+	}
+	StringStatus = map[string]Status{
+		"StatusPending": StatusPending,
+		"StatusRunning": StatusRunning,
+		"StatusFailure": StatusFailure,
+		"StatusSuccess": StatusSuccess,
+		"StatusAborted": StatusAborted,
+		"StatusSuspend": StatusSuspend,
+	}
+)
+
+// Workflow contains all steps to execute
 type Workflow interface {
-	Steps() [][]Step
-	Stop() error
+	// ID returns id of the workflow
+	ID() string
+	// Execute workflow with args, return execution id and 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
+	Resume(ctx context.Context, id string) error
+	// Abort abort execution
+	Abort(ctx context.Context, id string) error
 }
 
+// Flow the base interface to interact with workflows
 type Flow interface {
-	Start(Workflow) error
-	Stop(Workflow)
+	// Options returns options
+	Options() Options
+	// Init initialize
+	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
+	WorkflowSave(ctx context.Context, w Workflow) error
+	// WorkflowLoad loads workflow with specific id
+	WorkflowLoad(ctx context.Context, id string) (Workflow, error)
+	// WorkflowList lists all workflows
+	WorkflowList(ctx context.Context) ([]Workflow, error)
+}
+
+var (
+	flowMu      sync.Mutex
+	atomicSteps atomic.Value
+)
+
+func RegisterStep(step Step) {
+	flowMu.Lock()
+	steps, _ := atomicSteps.Load().([]Step)
+	atomicSteps.Store(append(steps, step))
+	flowMu.Unlock()
 }

flow/options.go

@@ -0,0 +1,230 @@
+package flow
+
+import (
+	"context"
+	"time"
+
+	"github.com/unistack-org/micro/v3/client"
+	"github.com/unistack-org/micro/v3/logger"
+	"github.com/unistack-org/micro/v3/meter"
+	"github.com/unistack-org/micro/v3/store"
+	"github.com/unistack-org/micro/v3/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
+	Context context.Context
+	// Client holds the client.Client
+	Client client.Client
+	// Tracer holds the tracer
+	Tracer tracer.Tracer
+	// Logger holds the logger
+	Logger logger.Logger
+	// Meter holds the meter
+	Meter meter.Meter
+	// Store used for intermediate results
+	Store store.Store
+}
+
+// NewOptions returns new options struct with default or passed values
+func NewOptions(opts ...Option) Options {
+	options := Options{
+		Context: context.Background(),
+		Logger:  logger.DefaultLogger,
+		Meter:   meter.DefaultMeter,
+		Tracer:  tracer.DefaultTracer,
+		Client:  client.DefaultClient,
+	}
+
+	for _, o := range opts {
+		o(&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
+// 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
+	}
+}
+
+// WorflowOption 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
+	}
+}
+
+type ExecuteOptions struct {
+	// Client holds the client.Client
+	Client client.Client
+	// Tracer holds the tracer
+	Tracer tracer.Tracer
+	// Logger holds the logger
+	Logger logger.Logger
+	// Meter holds the meter
+	Meter meter.Meter
+	// Context can be used to abort execution or pass additional opts
+	Context context.Context
+	// Start step
+	Start string
+	// Timeout for execution
+	Timeout time.Duration
+	// Reverse execution
+	Reverse bool
+	// Async enables async execution
+	Async bool
+}
+
+type ExecuteOption func(*ExecuteOptions)
+
+func ExecuteClient(c client.Client) ExecuteOption {
+	return func(o *ExecuteOptions) {
+		o.Client = c
+	}
+}
+
+func ExecuteTracer(t tracer.Tracer) ExecuteOption {
+	return func(o *ExecuteOptions) {
+		o.Tracer = t
+	}
+}
+
+func ExecuteLogger(l logger.Logger) ExecuteOption {
+	return func(o *ExecuteOptions) {
+		o.Logger = l
+	}
+}
+
+func ExecuteMeter(m meter.Meter) ExecuteOption {
+	return func(o *ExecuteOptions) {
+		o.Meter = m
+	}
+}
+
+func ExecuteContext(ctx context.Context) ExecuteOption {
+	return func(o *ExecuteOptions) {
+		o.Context = ctx
+	}
+}
+
+func ExecuteReverse(b bool) ExecuteOption {
+	return func(o *ExecuteOptions) {
+		o.Reverse = b
+	}
+}
+
+func ExecuteTimeout(td time.Duration) ExecuteOption {
+	return func(o *ExecuteOptions) {
+		o.Timeout = td
+	}
+}
+
+func ExecuteAsync(b bool) ExecuteOption {
+	return func(o *ExecuteOptions) {
+		o.Async = b
+	}
+}
+
+func NewExecuteOptions(opts ...ExecuteOption) ExecuteOptions {
+	options := ExecuteOptions{
+		Client:  client.DefaultClient,
+		Logger:  logger.DefaultLogger,
+		Tracer:  tracer.DefaultTracer,
+		Meter:   meter.DefaultMeter,
+		Context: context.Background(),
+	}
+	for _, o := range opts {
+		o(&options)
+	}
+	return options
+}
+
+type StepOptions struct {
+	Context  context.Context
+	Fallback string
+	ID       string
+	Requires []string
+}
+
+type StepOption func(*StepOptions)
+
+func NewStepOptions(opts ...StepOption) StepOptions {
+	options := StepOptions{
+		Context: context.Background(),
+	}
+	for _, o := range opts {
+		o(&options)
+	}
+	return options
+}
+
+func StepID(id string) StepOption {
+	return func(o *StepOptions) {
+		o.ID = id
+	}
+}
+
+func StepRequires(steps ...string) StepOption {
+	return func(o *StepOptions) {
+		o.Requires = steps
+	}
+}
+
+func StepFallback(step string) StepOption {
+	return func(o *StepOptions) {
+		o.Fallback = step
+	}
+}

go.mod

@@ -3,11 +3,12 @@ module github.com/unistack-org/micro/v3
 go 1.16
 
 require (
-	github.com/dgrijalva/jwt-go v3.2.0+incompatible
 	github.com/ef-ds/deque v1.0.4
-	github.com/google/uuid v1.2.0
+	github.com/golang-jwt/jwt/v4 v4.1.0
 	github.com/imdario/mergo v0.3.12
 	github.com/patrickmn/go-cache v2.1.0+incompatible
-	github.com/silas/dag v0.0.0-20210121180416-41cf55125c34
-	golang.org/x/net v0.0.0-20210510120150-4163338589ed
+	github.com/silas/dag v0.0.0-20210626123444-3804bac2d6d4
+	github.com/unistack-org/micro-proto v0.0.9
+	golang.org/x/net v0.0.0-20210928044308-7d9f5e0b762b
+	golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 // indirect
 )

go.sum

@@ -1,22 +1,37 @@
-github.com/dgrijalva/jwt-go v3.2.0+incompatible h1:7qlOGliEKZXTDg6OTjfoBKDXWrumCAMpl/TFQ4/5kLM=
-github.com/dgrijalva/jwt-go v3.2.0+incompatible/go.mod h1:E3ru+11k8xSBh+hMPgOLZmtrrCbhqsmaPHjLKYnJCaQ=
 github.com/ef-ds/deque v1.0.4 h1:iFAZNmveMT9WERAkqLJ+oaABF9AcVQ5AjXem/hroniI=
 github.com/ef-ds/deque v1.0.4/go.mod h1:gXDnTC3yqvBcHbq2lcExjtAcVrOnJCbMcZXmuj8Z4tg=
-github.com/google/uuid v1.2.0 h1:qJYtXnJRWmpe7m/3XlyhrsLrEURqHRM2kxzoxXqyUDs=
-github.com/google/uuid v1.2.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
+github.com/golang-jwt/jwt/v4 v4.0.0 h1:RAqyYixv1p7uEnocuy8P1nru5wprCh/MH2BIlW5z5/o=
+github.com/golang-jwt/jwt/v4 v4.0.0/go.mod h1:/xlHOz8bRuivTWchD4jCa+NbatV+wEUSzwAxVc6locg=
+github.com/golang-jwt/jwt/v4 v4.1.0 h1:XUgk2Ex5veyVFVeLm0xhusUTQybEbexJXrvPNOKkSY0=
+github.com/golang-jwt/jwt/v4 v4.1.0/go.mod h1:/xlHOz8bRuivTWchD4jCa+NbatV+wEUSzwAxVc6locg=
+github.com/golang/protobuf v1.5.0/go.mod h1:FsONVRAS9T7sI+LIUmWTfcYkHO4aIWwzhcaSAoJOfIk=
+github.com/google/go-cmp v0.5.5 h1:Khx7svrCpmxxtHBq5j2mp/xVjsi8hQMfNLvJFAlrGgU=
+github.com/google/go-cmp v0.5.5/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
 github.com/imdario/mergo v0.3.12 h1:b6R2BslTbIEToALKP7LxUvijTsNI9TAe80pLWN2g/HU=
 github.com/imdario/mergo v0.3.12/go.mod h1:jmQim1M+e3UYxmgPu/WyfjB3N3VflVyUjjjwH0dnCYA=
 github.com/patrickmn/go-cache v2.1.0+incompatible h1:HRMgzkcYKYpi3C8ajMPV8OFXaaRUnok+kx1WdO15EQc=
 github.com/patrickmn/go-cache v2.1.0+incompatible/go.mod h1:3Qf8kWWT7OJRJbdiICTKqZju1ZixQ/KpMGzzAfe6+WQ=
 github.com/silas/dag v0.0.0-20210121180416-41cf55125c34 h1:vBfVmA5mZhsQa2jr1FOL9nfA37N/jnbBmi5XUfviVTI=
 github.com/silas/dag v0.0.0-20210121180416-41cf55125c34/go.mod h1:7RTUFBdIRC9nZ7/3RyRNH1bdqIShrDejd1YbLwgPS+I=
-golang.org/x/net v0.0.0-20210510120150-4163338589ed h1:p9UgmWI9wKpfYmgaV/IZKGdXc5qEK45tDwwwDyjS26I=
-golang.org/x/net v0.0.0-20210510120150-4163338589ed/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
+github.com/silas/dag v0.0.0-20210626123444-3804bac2d6d4 h1:fOH64AB0C3ixGf9emky61STvPJL3smxJg+1Zwx1oCdg=
+github.com/silas/dag v0.0.0-20210626123444-3804bac2d6d4/go.mod h1:7RTUFBdIRC9nZ7/3RyRNH1bdqIShrDejd1YbLwgPS+I=
+github.com/unistack-org/micro-proto v0.0.9 h1:KrWLS4FUX7UAWNAilQf70uad6ZPf/0EudeddCXllRVc=
+github.com/unistack-org/micro-proto v0.0.9/go.mod h1:Cckwmzd89gvS7ThxzZp9kQR/EOdksFQcsTAtDDyKwrg=
+golang.org/x/net v0.0.0-20210805182204-aaa1db679c0d h1:20cMwl2fHAzkJMEA+8J4JgqBQcQGzbisXo31MIeenXI=
+golang.org/x/net v0.0.0-20210805182204-aaa1db679c0d/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
+golang.org/x/net v0.0.0-20210928044308-7d9f5e0b762b h1:eB48h3HiRycXNy8E0Gf5e0hv7YT6Kt14L/D73G1fuwo=
+golang.org/x/net v0.0.0-20210928044308-7d9f5e0b762b/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
 golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20210423082822-04245dca01da/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
 golang.org/x/text v0.3.6/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
+golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
+golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 h1:go1bK/D/BFZV2I8cIQd1NKEZ+0owSTG1fDTci4IqFcE=
+golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
+google.golang.org/protobuf v1.26.0-rc.1/go.mod h1:jlhhOSvTdKEhbULTjvd4ARK9grFBp09yW+WbY/TyQbw=
+google.golang.org/protobuf v1.27.1 h1:SnqbnDw1V7RiZcXPx5MEeqPv2s79L9i7BJUlG/+RurQ=
+google.golang.org/protobuf v1.27.1/go.mod h1:9q0QmTI4eRPtz6boOQmLYwt+qCgq0jsYwAQnmE0givc=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v2 v2.3.0 h1:clyUAQHOM3G0M3f5vQj7LuJrETvjVot3Z5el9nffUtU=
 gopkg.in/yaml.v2 v2.3.0/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=

logger/default.go

@@ -11,18 +11,11 @@ import (
 	"time"
 )
 
-func init() {
-	lvl, err := GetLevel(os.Getenv("MICRO_LOG_LEVEL"))
-	if err != nil {
-		lvl = InfoLevel
-	}
-
-	DefaultLogger = NewLogger(WithLevel(lvl))
-}
-
 type defaultLogger struct {
-	enc  *json.Encoder
-	opts Options
+	enc      *json.Encoder
+	logFunc  LogFunc
+	logfFunc LogfFunc
+	opts     Options
 	sync.RWMutex
 }
 
@@ -33,6 +26,11 @@ func (l *defaultLogger) Init(opts ...Option) error {
 		o(&l.opts)
 	}
 	l.enc = json.NewEncoder(l.opts.Out)
+	// wrap the Log func
+	for i := len(l.opts.Wrappers); i > 0; i-- {
+		l.logFunc = l.opts.Wrappers[i-1].Log(l.logFunc)
+		l.logfFunc = l.opts.Wrappers[i-1].Logf(l.logfFunc)
+	}
 	l.Unlock()
 	return nil
 }
@@ -41,6 +39,28 @@ func (l *defaultLogger) String() string {
 	return "micro"
 }
 
+func (l *defaultLogger) Clone(opts ...Option) Logger {
+	newopts := NewOptions(opts...)
+	oldopts := l.opts
+	for _, o := range opts {
+		o(&newopts)
+		o(&oldopts)
+	}
+
+	oldopts.Wrappers = newopts.Wrappers
+	l.Lock()
+	cl := &defaultLogger{opts: oldopts, logFunc: l.logFunc, logfFunc: l.logfFunc}
+	l.Unlock()
+
+	// wrap the Log func
+	for i := len(newopts.Wrappers); i > 0; i-- {
+		cl.logFunc = newopts.Wrappers[i-1].Log(cl.logFunc)
+		cl.logfFunc = newopts.Wrappers[i-1].Logf(cl.logfFunc)
+	}
+
+	return cl
+}
+
 func (l *defaultLogger) V(level Level) bool {
 	l.RLock()
 	ok := l.opts.Level.Enabled(level)
@@ -48,26 +68,26 @@ func (l *defaultLogger) V(level Level) bool {
 	return ok
 }
 
-func (l *defaultLogger) Fields(fields map[string]interface{}) Logger {
-	nl := &defaultLogger{opts: l.opts, enc: l.enc}
-	nl.opts.Fields = make(map[string]interface{}, len(l.opts.Fields)+len(fields))
-	l.RLock()
-	for k, v := range l.opts.Fields {
-		nl.opts.Fields[k] = v
-	}
-	l.RUnlock()
+func (l *defaultLogger) Level(level Level) {
+	l.Lock()
+	l.opts.Level = level
+	l.Unlock()
+}
 
-	for k, v := range fields {
-		nl.opts.Fields[k] = v
+func (l *defaultLogger) Fields(fields ...interface{}) Logger {
+	nl := &defaultLogger{opts: l.opts, enc: l.enc}
+	if len(fields) == 0 {
+		return nl
+	} else if len(fields)%2 != 0 {
+		fields = fields[:len(fields)-1]
 	}
+	nl.opts.Fields = append(nl.opts.Fields, fields...)
 	return nl
 }
 
-func copyFields(src map[string]interface{}) map[string]interface{} {
-	dst := make(map[string]interface{}, len(src))
-	for k, v := range src {
-		dst[k] = v
-	}
+func copyFields(src []interface{}) []interface{} {
+	dst := make([]interface{}, len(src))
+	copy(dst, src)
 	return dst
 }
 
@@ -121,27 +141,27 @@ func (l *defaultLogger) Fatal(ctx context.Context, args ...interface{}) {
 }
 
 func (l *defaultLogger) Infof(ctx context.Context, msg string, args ...interface{}) {
-	l.Logf(ctx, InfoLevel, msg, args...)
+	l.logfFunc(ctx, InfoLevel, msg, args...)
 }
 
 func (l *defaultLogger) Errorf(ctx context.Context, msg string, args ...interface{}) {
-	l.Logf(ctx, ErrorLevel, msg, args...)
+	l.logfFunc(ctx, ErrorLevel, msg, args...)
 }
 
 func (l *defaultLogger) Debugf(ctx context.Context, msg string, args ...interface{}) {
-	l.Logf(ctx, DebugLevel, msg, args...)
+	l.logfFunc(ctx, DebugLevel, msg, args...)
 }
 
 func (l *defaultLogger) Warnf(ctx context.Context, msg string, args ...interface{}) {
-	l.Logf(ctx, WarnLevel, msg, args...)
+	l.logfFunc(ctx, WarnLevel, msg, args...)
 }
 
 func (l *defaultLogger) Tracef(ctx context.Context, msg string, args ...interface{}) {
-	l.Logf(ctx, TraceLevel, msg, args...)
+	l.logfFunc(ctx, TraceLevel, msg, args...)
 }
 
 func (l *defaultLogger) Fatalf(ctx context.Context, msg string, args ...interface{}) {
-	l.Logf(ctx, FatalLevel, msg, args...)
+	l.logfFunc(ctx, FatalLevel, msg, args...)
 	os.Exit(1)
 }
 
@@ -154,19 +174,23 @@ func (l *defaultLogger) Log(ctx context.Context, level Level, args ...interface{
 	fields := copyFields(l.opts.Fields)
 	l.RUnlock()
 
-	fields["level"] = level.String()
+	fields = append(fields, "level", level.String())
 
 	if _, file, line, ok := runtime.Caller(l.opts.CallerSkipCount); ok {
-		fields["caller"] = fmt.Sprintf("%s:%d", logCallerfilePath(file), line)
+		fields = append(fields, "caller", fmt.Sprintf("%s:%d", logCallerfilePath(file), line))
 	}
+	fields = append(fields, "timestamp", time.Now().Format("2006-01-02 15:04:05"))
 
-	fields["timestamp"] = time.Now().Format("2006-01-02 15:04:05")
 	if len(args) > 0 {
-		fields["msg"] = fmt.Sprint(args...)
+		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(fields)
+	_ = l.enc.Encode(out)
 	l.RUnlock()
 }
 
@@ -179,35 +203,39 @@ func (l *defaultLogger) Logf(ctx context.Context, level Level, msg string, args
 	fields := copyFields(l.opts.Fields)
 	l.RUnlock()
 
-	fields["level"] = level.String()
+	fields = append(fields, "level", level.String())
 
 	if _, file, line, ok := runtime.Caller(l.opts.CallerSkipCount); ok {
-		fields["caller"] = fmt.Sprintf("%s:%d", logCallerfilePath(file), line)
+		fields = append(fields, "caller", fmt.Sprintf("%s:%d", logCallerfilePath(file), line))
 	}
 
-	fields["timestamp"] = time.Now().Format("2006-01-02 15:04:05")
+	fields = append(fields, "timestamp", time.Now().Format("2006-01-02 15:04:05"))
 	if len(args) > 0 {
-		fields["msg"] = fmt.Sprintf(msg, args...)
+		fields = append(fields, "msg", fmt.Sprintf(msg, args...))
 	} else if msg != "" {
-		fields["msg"] = 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(fields)
+	_ = l.enc.Encode(out)
 	l.RUnlock()
 }
 
 func (l *defaultLogger) Options() Options {
-	// not guard against options Context values
-	l.RLock()
-	opts := l.opts
-	opts.Fields = copyFields(l.opts.Fields)
-	l.RUnlock()
-	return opts
+	return l.opts
 }
 
 // NewLogger builds a new logger based on options
 func NewLogger(opts ...Option) Logger {
-	l := &defaultLogger{opts: NewOptions(opts...)}
+	l := &defaultLogger{
+		opts: NewOptions(opts...),
+	}
+	l.logFunc = l.Log
+	l.logfFunc = l.Logf
 	l.enc = json.NewEncoder(l.opts.Out)
 	return l
 }

logger/level.go

@@ -1,24 +1,20 @@
 package logger
 
-import (
-	"fmt"
-)
-
 // Level means logger level
 type Level int8
 
 const (
-	// TraceLevel level. Designates finer-grained informational events than the Debug.
+	// TraceLevel level usually used to find bugs, very verbose
 	TraceLevel Level = iota - 2
-	// DebugLevel level. Usually only enabled when debugging. Very verbose logging.
+	// DebugLevel level used only when enabled debugging
 	DebugLevel
-	// InfoLevel level. General operational entries about what's going on inside the application.
+	// InfoLevel level used for general info about what's going on inside the application
 	InfoLevel
-	// WarnLevel level. Non-critical entries that deserve eyes.
+	// WarnLevel level used for non-critical entries
 	WarnLevel
-	// ErrorLevel level. Used for errors that should definitely be noted.
+	// ErrorLevel level used for errors that should definitely be noted
 	ErrorLevel
-	// FatalLevel level. Logs and then calls `os.Exit(1)`. highest level of severity.
+	// FatalLevel level used for critical errors and then calls `os.Exit(1)`
 	FatalLevel
 )
 
@@ -38,7 +34,7 @@ func (l Level) String() string {
 	case FatalLevel:
 		return "fatal"
 	}
-	return ""
+	return "info"
 }
 
 // Enabled returns true if the given level is at or above this level.
@@ -46,22 +42,22 @@ func (l Level) Enabled(lvl Level) bool {
 	return lvl >= l
 }
 
-// GetLevel converts a level string into a logger Level value.
-// returns an error if the input string does not match known values.
-func GetLevel(levelStr string) (Level, error) {
-	switch levelStr {
+// ParseLevel converts a level string into a logger Level value.
+// returns an InfoLevel if the input string does not match known values.
+func ParseLevel(lvl string) Level {
+	switch lvl {
 	case TraceLevel.String():
-		return TraceLevel, nil
+		return TraceLevel
 	case DebugLevel.String():
-		return DebugLevel, nil
+		return DebugLevel
 	case InfoLevel.String():
-		return InfoLevel, nil
+		return InfoLevel
 	case WarnLevel.String():
-		return WarnLevel, nil
+		return WarnLevel
 	case ErrorLevel.String():
-		return ErrorLevel, nil
+		return ErrorLevel
 	case FatalLevel.String():
-		return FatalLevel, nil
+		return FatalLevel
 	}
-	return InfoLevel, fmt.Errorf("unknown Level String: '%s', use InfoLevel", levelStr)
+	return InfoLevel
 }

logger/logger.go

@@ -1,25 +1,34 @@
 // Package logger provides a log interface
 package logger
 
-import "context"
+import (
+	"context"
+	"os"
+)
 
 var (
 	// DefaultLogger variable
-	DefaultLogger Logger = NewLogger()
+	DefaultLogger Logger = NewLogger(WithLevel(ParseLevel(os.Getenv("MICRO_LOG_LEVEL"))))
 	// DefaultLevel used by logger
 	DefaultLevel Level = InfoLevel
+	// DefaultCallerSkipCount used by logger
+	DefaultCallerSkipCount = 2
 )
 
 // Logger is a generic logging interface
 type Logger interface {
 	// Init initialises options
 	Init(opts ...Option) error
+	// Clone create logger copy with new options
+	Clone(opts ...Option) Logger
 	// V compare provided verbosity level with current log level
 	V(level Level) bool
+	// Level sets the log level for logger
+	Level(level Level)
 	// The Logger options
 	Options() Options
-	// Fields set fields to always be logged
-	Fields(fields map[string]interface{}) Logger
+	// Fields set fields to always be logged with keyval pairs
+	Fields(fields ...interface{}) Logger
 	// Info level message
 	Info(ctx context.Context, args ...interface{})
 	// Trace level message
@@ -52,6 +61,9 @@ type Logger interface {
 	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...)
@@ -123,6 +135,6 @@ func Init(opts ...Option) error {
 }
 
 // Fields create logger with specific fields
-func Fields(fields map[string]interface{}) Logger {
-	return DefaultLogger.Fields(fields)
+func Fields(fields ...interface{}) Logger {
+	return DefaultLogger.Fields(fields...)
 }

logger/logger_test.go

@@ -1,18 +1,117 @@
 package logger
 
 import (
+	"bytes"
 	"context"
+	"log"
 	"testing"
 )
 
+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()
-	l := NewLogger(WithLevel(TraceLevel))
+	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(map[string]interface{}{"error": "test"}).Info(ctx, "error message")
+	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())
+	}
+}
+
+func TestLoggerWrapper(t *testing.T) {
+	ctx := context.TODO()
+	buf := bytes.NewBuffer(nil)
+	l := NewLogger(WithLevel(TraceLevel), WithOutput(buf))
+	if err := l.Init(WrapLogger(NewOmitWrapper())); err != nil {
+		t.Fatal(err)
+	}
+	type secret struct {
+		Name  string
+		Passw string `logger:"omit"`
+	}
+	s := &secret{Name: "name", Passw: "secret"}
+	l.Errorf(ctx, "test %#+v", s)
+	if !bytes.Contains(buf.Bytes(), []byte(`logger.secret{Name:\"name\", Passw:\"\"}"`)) {
+		t.Fatalf("omit not works, struct: %v, output: %s", s, buf.Bytes())
+	}
+}
+
+func TestOmitLoggerWrapper(t *testing.T) {
+	ctx := context.TODO()
+	buf := bytes.NewBuffer(nil)
+	l := NewOmitLogger(NewLogger(WithLevel(TraceLevel), WithOutput(buf)))
+	if err := l.Init(); err != nil {
+		t.Fatal(err)
+	}
+	type secret struct {
+		Name  string
+		Passw string `logger:"omit"`
+	}
+	s := &secret{Name: "name", Passw: "secret"}
+	l.Errorf(ctx, "test %#+v", s)
+	if !bytes.Contains(buf.Bytes(), []byte(`logger.secret{Name:\"name\", Passw:\"\"}"`)) {
+		t.Fatalf("omit not works, struct: %v, output: %s", s, buf.Bytes())
+	}
 }

logger/options.go

@@ -16,22 +16,24 @@ type Options struct {
 	// Context holds exernal options
 	Context context.Context
 	// Fields holds additional metadata
-	Fields map[string]interface{}
+	Fields []interface{}
 	// Name holds the logger name
 	Name string
-	// CallerSkipCount number of frmaes to skip
-	CallerSkipCount int
+	// Wrappers logger wrapper that called before actual Log/Logf function
+	Wrappers []Wrapper
 	// The logging level the logger should log
 	Level Level
+	// CallerSkipCount number of frmaes to skip
+	CallerSkipCount int
 }
 
 // NewOptions creates new options struct
 func NewOptions(opts ...Option) Options {
 	options := Options{
 		Level:           DefaultLevel,
-		Fields:          make(map[string]interface{}),
+		Fields:          make([]interface{}, 0, 6),
 		Out:             os.Stderr,
-		CallerSkipCount: 0,
+		CallerSkipCount: DefaultCallerSkipCount,
 		Context:         context.Background(),
 	}
 	for _, o := range opts {
@@ -41,7 +43,7 @@ func NewOptions(opts ...Option) Options {
 }
 
 // WithFields set default fields for the logger
-func WithFields(fields map[string]interface{}) Option {
+func WithFields(fields ...interface{}) Option {
 	return func(o *Options) {
 		o.Fields = fields
 	}
@@ -81,3 +83,10 @@ func WithName(n string) Option {
 		o.Name = n
 	}
 }
+
+// WrapLogger adds a logger Wrapper to a list of options passed into the logger
+func WrapLogger(w Wrapper) Option {
+	return func(o *Options) {
+		o.Wrappers = append(o.Wrappers, w)
+	}
+}

logger/stdlogger.go

@@ -0,0 +1,35 @@
+package logger
+
+import (
+	"bytes"
+	"log"
+)
+
+type stdLogger struct {
+	l     Logger
+	level Level
+}
+
+func NewStdLogger(l Logger, level Level) *log.Logger {
+	return log.New(&stdLogger{l: l, level: level}, "" /* prefix */, 0 /* flags */)
+}
+
+func (sl *stdLogger) Write(p []byte) (int, error) {
+	p = bytes.TrimSpace(p)
+	sl.l.Log(sl.l.Options().Context, sl.level, string(p))
+	return len(p), nil
+}
+
+func RedirectStdLogger(l Logger, level Level) func() {
+	flags := log.Flags()
+	prefix := log.Prefix()
+	writer := log.Writer()
+	log.SetFlags(0)
+	log.SetPrefix("")
+	log.SetOutput(&stdLogger{l: l, level: level})
+	return func() {
+		log.SetFlags(flags)
+		log.SetPrefix(prefix)
+		log.SetOutput(writer)
+	}
+}

logger/wrapper.go

@@ -0,0 +1,166 @@
+package logger
+
+import (
+	"context"
+	"reflect"
+
+	rutil "github.com/unistack-org/micro/v3/util/reflect"
+)
+
+// LogFunc function used for Log method
+type LogFunc func(ctx context.Context, level Level, args ...interface{})
+
+// LogfFunc function used for Logf method
+type LogfFunc func(ctx context.Context, level Level, msg string, args ...interface{})
+
+type Wrapper interface {
+	// Log logs message with needed level
+	Log(LogFunc) LogFunc
+	// Logf logs message with needed level
+	Logf(LogfFunc) LogfFunc
+}
+
+var _ Logger = &OmitLogger{}
+
+type OmitLogger struct {
+	l Logger
+}
+
+func NewOmitLogger(l Logger) Logger {
+	return &OmitLogger{l: l}
+}
+
+func (w *OmitLogger) Init(opts ...Option) error {
+	return w.l.Init(append(opts, WrapLogger(NewOmitWrapper()))...)
+}
+
+func (w *OmitLogger) V(level Level) bool {
+	return w.l.V(level)
+}
+
+func (w *OmitLogger) Level(level Level) {
+	w.l.Level(level)
+}
+
+func (w *OmitLogger) Clone(opts ...Option) Logger {
+	return w.l.Clone(opts...)
+}
+
+func (w *OmitLogger) Options() Options {
+	return w.l.Options()
+}
+
+func (w *OmitLogger) Fields(fields ...interface{}) Logger {
+	return w.l.Fields(fields...)
+}
+
+func (w *OmitLogger) Info(ctx context.Context, args ...interface{}) {
+	w.l.Info(ctx, args...)
+}
+
+func (w *OmitLogger) Trace(ctx context.Context, args ...interface{}) {
+	w.l.Trace(ctx, args...)
+}
+
+func (w *OmitLogger) Debug(ctx context.Context, args ...interface{}) {
+	w.l.Debug(ctx, args...)
+}
+
+func (w *OmitLogger) Warn(ctx context.Context, args ...interface{}) {
+	w.l.Warn(ctx, args...)
+}
+
+func (w *OmitLogger) Error(ctx context.Context, args ...interface{}) {
+	w.l.Error(ctx, args...)
+}
+
+func (w *OmitLogger) Fatal(ctx context.Context, args ...interface{}) {
+	w.l.Fatal(ctx, args...)
+}
+
+func (w *OmitLogger) Infof(ctx context.Context, msg string, args ...interface{}) {
+	w.l.Infof(ctx, msg, args...)
+}
+
+func (w *OmitLogger) Tracef(ctx context.Context, msg string, args ...interface{}) {
+	w.l.Tracef(ctx, msg, args...)
+}
+
+func (w *OmitLogger) Debugf(ctx context.Context, msg string, args ...interface{}) {
+	w.l.Debugf(ctx, msg, args...)
+}
+
+func (w *OmitLogger) Warnf(ctx context.Context, msg string, args ...interface{}) {
+	w.l.Warnf(ctx, msg, args...)
+}
+
+func (w *OmitLogger) Errorf(ctx context.Context, msg string, args ...interface{}) {
+	w.l.Errorf(ctx, msg, args...)
+}
+
+func (w *OmitLogger) Fatalf(ctx context.Context, msg string, args ...interface{}) {
+	w.l.Fatalf(ctx, msg, args...)
+}
+
+func (w *OmitLogger) Log(ctx context.Context, level Level, args ...interface{}) {
+	w.l.Log(ctx, level, args...)
+}
+
+func (w *OmitLogger) Logf(ctx context.Context, level Level, msg string, args ...interface{}) {
+	w.l.Logf(ctx, level, msg, args...)
+}
+
+func (w *OmitLogger) String() string {
+	return w.l.String()
+}
+
+type OmitWrapper struct{}
+
+func NewOmitWrapper() Wrapper {
+	return &OmitWrapper{}
+}
+
+func getArgs(args []interface{}) []interface{} {
+	nargs := make([]interface{}, 0, len(args))
+	var err error
+	for _, arg := range args {
+		val := reflect.ValueOf(arg)
+		if val.Kind() == reflect.Ptr {
+			val = val.Elem()
+		}
+		narg := arg
+		if val.Kind() != reflect.Struct {
+			nargs = append(nargs, narg)
+			continue
+		}
+
+		if narg, err = rutil.Zero(arg); err != nil {
+			nargs = append(nargs, narg)
+			continue
+		}
+
+		rutil.CopyDefaults(narg, arg)
+		if flds, ferr := rutil.StructFields(narg); ferr == nil {
+			for _, fld := range flds {
+				if tv, ok := fld.Field.Tag.Lookup("logger"); ok && tv == "omit" {
+					fld.Value.Set(reflect.Zero(fld.Value.Type()))
+				}
+			}
+		}
+
+		nargs = append(nargs, narg)
+	}
+	return nargs
+}
+
+func (w *OmitWrapper) Log(fn LogFunc) LogFunc {
+	return func(ctx context.Context, level Level, args ...interface{}) {
+		fn(ctx, level, getArgs(args)...)
+	}
+}
+
+func (w *OmitWrapper) Logf(fn LogfFunc) LogfFunc {
+	return func(ctx context.Context, level Level, msg string, args ...interface{}) {
+		fn(ctx, level, msg, getArgs(args)...)
+	}
+}

metadata/metadata.go

@@ -6,8 +6,20 @@ import (
 	"sort"
 )
 
-// HeaderPrefix for all headers passed
-var HeaderPrefix = "Micro-"
+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
@@ -95,13 +107,16 @@ func New(size int) Metadata {
 
 // 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 {
-		if _, ok := nmd[key]; ok && !overwrite {
-			// skip
-		} else if val != "" {
+		_, ok = nmd[key]
+		switch {
+		case ok && !overwrite:
+			continue
+		case val != "":
 			nmd.Set(key, val)
-		} else {
+		case ok && val == "":
 			nmd.Del(key)
 		}
 	}

meter/generate.go

@@ -1,3 +1,12 @@
 package meter
 
-//go:generate protoc -I./handler -I../ -I/home/vtolstov/.cache/go-path/pkg/mod/github.com/unistack-org/micro-proto@v0.0.1 --micro_out=components=micro|http|server,standalone=false,debug=true,paths=source_relative:./handler handler/handler.proto
+//go:generate sh -c "protoc -I./handler -I../ -I$(go list -f '{{ .Dir }}' -m github.com/unistack-org/micro-proto) --go-micro_out='components=micro|http|server',standalone=false,debug=true,paths=source_relative:./handler handler/handler.proto"
+
+import (
+
+	// import required packages
+	_ "github.com/unistack-org/micro-proto/api"
+
+	// import required packages
+	_ "github.com/unistack-org/micro-proto/openapiv2"
+)

meter/handler/handler.proto

@@ -11,17 +11,17 @@ service Meter {
 	rpc Metrics(micro.codec.Frame) returns (micro.codec.Frame) {
 		option (micro.openapiv2.openapiv2_operation) = {
       operation_id: "Metrics";
-        responses: {
-          key: "default";
+      responses: {
+        response_code: {
+          name: "default";
           value: {
-            description: "Error response";
-            schema: {
-              json_schema: {
-                ref: "micro.codec.Frame";
-              }
-            }
-          }
-        }
+            json_reference: {
+              description: "Error response";
+              _ref: "micro.codec.Frame";
+            };
+          };
+        };
+      };
     };
 		option (micro.api.http) = { get: "/metrics"; };
   };

meter/handler/handler_micro.pb.go

@@ -1,22 +1,31 @@
-// Code generated by protoc-gen-micro
+// Code generated by protoc-gen-go-micro. DO NOT EDIT.
+// protoc-gen-go-micro version: v3.4.2
 // source: handler.proto
+
 package handler
 
 import (
 	context "context"
+
 	api "github.com/unistack-org/micro/v3/api"
 	codec "github.com/unistack-org/micro/v3/codec"
 )
 
-func NewMeterEndpoints() []*api.Endpoint {
-	return []*api.Endpoint{
-		&api.Endpoint{
+var (
+	MeterName = "Meter"
+
+	MeterEndpoints = []api.Endpoint{
+		{
 			Name:    "Meter.Metrics",
 			Path:    []string{"/metrics"},
 			Method:  []string{"GET"},
 			Handler: "rpc",
 		},
 	}
+)
+
+func NewMeterEndpoints() []api.Endpoint {
+	return MeterEndpoints
 }
 
 type MeterServer interface {

meter/handler/handler_micro_http.pb.go

@@ -1,9 +1,12 @@
-// Code generated by protoc-gen-micro
+// Code generated by protoc-gen-go-micro. DO NOT EDIT.
+// protoc-gen-go-micro version: v3.4.2
 // source: handler.proto
+
 package handler
 
 import (
 	context "context"
+
 	api "github.com/unistack-org/micro/v3/api"
 	codec "github.com/unistack-org/micro/v3/codec"
 	server "github.com/unistack-org/micro/v3/server"
@@ -26,8 +29,8 @@ func RegisterMeterServer(s server.Server, sh MeterServer, opts ...server.Handler
 	}
 	h := &meterServer{sh}
 	var nopts []server.HandlerOption
-	for _, endpoint := range NewMeterEndpoints() {
-		nopts = append(nopts, api.WithEndpoint(endpoint))
+	for _, endpoint := range MeterEndpoints {
+		nopts = append(nopts, api.WithEndpoint(&endpoint))
 	}
 	return s.Handle(s.NewHandler(&Meter{h}, append(nopts, opts...)...))
 }

meter/meter.go

@@ -3,8 +3,9 @@ package meter
 
 import (
 	"io"
-	"reflect"
 	"sort"
+	"strconv"
+	"strings"
 	"time"
 )
 
@@ -77,36 +78,62 @@ type Summary interface {
 	UpdateDuration(time.Time)
 }
 
+// sort labels alphabeticaly by label name
 type byKey []string
 
 func (k byKey) Len() int           { return len(k) / 2 }
 func (k byKey) Less(i, j int) bool { return k[i*2] < k[j*2] }
 func (k byKey) Swap(i, j int) {
-	k[i*2], k[i*2+1], k[j*2], k[j*2+1] = k[j*2], k[j*2+1], k[i*2], k[i*2+1]
+	k[i*2], k[j*2] = k[j*2], k[i*2]
+	k[i*2+1], k[j*2+1] = k[j*2+1], k[i*2+1]
 }
 
-func Sort(slice *[]string) {
-	bk := byKey(*slice)
-	if bk.Len() <= 1 {
-		return
+// BuildLables used to sort labels and delete duplicates.
+// Last value wins in case of duplicate label keys.
+func BuildLabels(labels ...string) []string {
+	if len(labels)%2 == 1 {
+		labels = labels[:len(labels)-1]
 	}
-	sort.Sort(bk)
-	v := reflect.ValueOf(slice).Elem()
-	cnt := 0
-	key := 0
-	val := 1
-	for key < v.Len() {
-		if len(bk) > key+2 && bk[key] == bk[key+2] {
-			key += 2
-			val += 2
-			continue
-		}
-		v.Index(cnt).Set(v.Index(key))
-		cnt++
-		v.Index(cnt).Set(v.Index(val))
-		cnt++
-		key += 2
-		val += 2
-	}
-	v.SetLen(cnt)
+	sort.Sort(byKey(labels))
+	return labels
+}
+
+// BuildName used to combine metric with labels.
+// If labels count is odd, drop last element
+func BuildName(name string, labels ...string) string {
+	if len(labels)%2 == 1 {
+		labels = labels[:len(labels)-1]
+	}
+
+	if len(labels) > 2 {
+		sort.Sort(byKey(labels))
+
+		idx := 0
+		for {
+			if labels[idx] == labels[idx+2] {
+				copy(labels[idx:], labels[idx+2:])
+				labels = labels[:len(labels)-2]
+			} else {
+				idx += 2
+			}
+			if idx+2 >= len(labels) {
+				break
+			}
+		}
+	}
+
+	var b strings.Builder
+	_, _ = b.WriteString(name)
+	_, _ = b.WriteRune('{')
+	for idx := 0; idx < len(labels); idx += 2 {
+		if idx > 0 {
+			_, _ = b.WriteRune(',')
+		}
+		_, _ = b.WriteString(labels[idx])
+		_, _ = b.WriteString(`=`)
+		_, _ = b.WriteString(strconv.Quote(labels[idx+1]))
+	}
+	_, _ = b.WriteRune('}')
+
+	return b.String()
 }

meter/meter_test.go

@@ -14,11 +14,57 @@ func TestNoopMeter(t *testing.T) {
 	cnt.Inc()
 }
 
-func TestLabelsSort(t *testing.T) {
-	ls := []string{"server", "http", "register", "mdns", "broker", "broker1", "broker", "broker2", "server", "tcp"}
-	Sort(&ls)
+func testEq(a, b []string) bool {
+	if len(a) != len(b) {
+		return false
+	}
+	for i := range a {
+		if a[i] != b[i] {
+			return false
+		}
+	}
+	return true
+}
 
-	if ls[0] != "broker" || ls[1] != "broker2" {
-		t.Fatalf("sort error: %v", ls)
+func TestBuildLabels(t *testing.T) {
+	type testData struct {
+		src []string
+		dst []string
+	}
+
+	data := []testData{
+		{
+			src: []string{"zerolabel", "value3", "firstlabel", "value2"},
+			dst: []string{"firstlabel", "value2", "zerolabel", "value3"},
+		},
+	}
+
+	for _, d := range data {
+		if !testEq(d.dst, BuildLabels(d.src...)) {
+			t.Fatalf("slices not properly sorted: %v %v", d.dst, d.src)
+		}
+	}
+}
+
+func TestBuildName(t *testing.T) {
+	data := map[string][]string{
+		`my_metric{firstlabel="value2",zerolabel="value3"}`: {
+			"my_metric",
+			"zerolabel", "value3", "firstlabel", "value2",
+		},
+		`my_metric{broker="broker2",register="mdns",server="tcp"}`: {
+			"my_metric",
+			"broker", "broker1", "broker", "broker2", "server", "http", "server", "tcp", "register", "mdns",
+		},
+		`my_metric{aaa="aaa"}`: {
+			"my_metric",
+			"aaa", "aaa",
+		},
+	}
+
+	for e, d := range data {
+		if x := BuildName(d[0], d[1:]...); x != e {
+			t.Fatalf("expect: %s, result: %s", e, x)
+		}
 	}
 }

network/options.go

@@ -1,13 +1,13 @@
 package network
 
 import (
-	"github.com/google/uuid"
 	"github.com/unistack-org/micro/v3/logger"
 	"github.com/unistack-org/micro/v3/meter"
 	"github.com/unistack-org/micro/v3/network/tunnel"
 	"github.com/unistack-org/micro/v3/proxy"
 	"github.com/unistack-org/micro/v3/router"
 	"github.com/unistack-org/micro/v3/tracer"
+	"github.com/unistack-org/micro/v3/util/id"
 )
 
 // Option func
@@ -27,8 +27,8 @@ type Options struct {
 	Tracer tracer.Tracer
 	// Tunnel used for transfer data
 	Tunnel tunnel.Tunnel
-	// Id of the node
-	Id string
+	// ID of the node
+	ID string
 	// Name of the network
 	Name string
 	// Address to bind to
@@ -39,10 +39,10 @@ type Options struct {
 	Nodes []string
 }
 
-// Id sets the id of the network node
-func Id(id string) Option {
+// ID sets the id of the network node
+func ID(id string) Option {
 	return func(o *Options) {
-		o.Id = id
+		o.ID = id
 	}
 }
 
@@ -119,7 +119,7 @@ func Tracer(t tracer.Tracer) Option {
 // NewOptions returns network default options
 func NewOptions(opts ...Option) Options {
 	options := Options{
-		Id:      uuid.New().String(),
+		ID:      id.Must(),
 		Name:    "go.micro",
 		Address: ":0",
 		Logger:  logger.DefaultLogger,

network/transport/memory_test.go

@@ -16,12 +16,14 @@ func TestMemoryTransport(t *testing.T) {
 	}
 	defer l.Close()
 
+	cherr := make(chan error, 1)
 	// accept
 	go func() {
-		if err := l.Accept(func(sock Socket) {
+		if nerr := l.Accept(func(sock Socket) {
 			for {
 				var m Message
-				if err := sock.Recv(&m); err != nil {
+				if rerr := sock.Recv(&m); rerr != nil {
+					cherr <- rerr
 					return
 				}
 				if len(os.Getenv("INTEGRATION_TESTS")) == 0 {
@@ -30,11 +32,12 @@ func TestMemoryTransport(t *testing.T) {
 				if cerr := sock.Send(&Message{
 					Body: []byte(`pong`),
 				}); cerr != nil {
+					cherr <- cerr
 					return
 				}
 			}
-		}); err != nil {
-			t.Fatalf("Unexpected error accepting %v", err)
+		}); nerr != nil {
+			cherr <- err
 		}
 	}()
 
@@ -45,19 +48,24 @@ func TestMemoryTransport(t *testing.T) {
 	}
 	defer c.Close()
 
-	// send <=> receive
-	for i := 0; i < 3; i++ {
-		if err := c.Send(&Message{
-			Body: []byte(`ping`),
-		}); err != nil {
-			return
-		}
-		var m Message
-		if err := c.Recv(&m); err != nil {
-			return
-		}
-		if len(os.Getenv("INTEGRATION_TESTS")) == 0 {
-			t.Logf("Client Received %s", string(m.Body))
+	select {
+	case err := <-cherr:
+		t.Fatal(err)
+	default:
+		// send <=> receive
+		for i := 0; i < 3; i++ {
+			if err := c.Send(&Message{
+				Body: []byte(`ping`),
+			}); err != nil {
+				return
+			}
+			var m Message
+			if err := c.Recv(&m); err != nil {
+				return
+			}
+			if len(os.Getenv("INTEGRATION_TESTS")) == 0 {
+				t.Logf("Client Received %s", string(m.Body))
+			}
 		}
 	}
 }

network/tunnel/broker/broker.go

@@ -7,6 +7,7 @@ import (
 
 	"github.com/unistack-org/micro/v3/broker"
 	"github.com/unistack-org/micro/v3/logger"
+	"github.com/unistack-org/micro/v3/metadata"
 	"github.com/unistack-org/micro/v3/network/transport"
 	"github.com/unistack-org/micro/v3/network/tunnel"
 )
@@ -24,7 +25,16 @@ type tunSubscriber struct {
 	opts     broker.SubscribeOptions
 }
 
+type tunBatchSubscriber struct {
+	listener tunnel.Listener
+	handler  broker.BatchHandler
+	closed   chan bool
+	topic    string
+	opts     broker.SubscribeOptions
+}
+
 type tunEvent struct {
+	err     error
 	message *broker.Message
 	topic   string
 }
@@ -62,6 +72,36 @@ func (t *tunBroker) Disconnect(ctx context.Context) error {
 	return t.tunnel.Close(ctx)
 }
 
+func (t *tunBroker) BatchPublish(ctx context.Context, msgs []*broker.Message, opts ...broker.PublishOption) error {
+	// TODO: this is probably inefficient, we might want to just maintain an open connection
+	// it may be easier to add broadcast to the tunnel
+	topicMap := make(map[string]tunnel.Session)
+
+	var err error
+	for _, msg := range msgs {
+		topic, _ := msg.Header.Get(metadata.HeaderTopic)
+		c, ok := topicMap[topic]
+		if !ok {
+			c, err = t.tunnel.Dial(ctx, topic, tunnel.DialMode(tunnel.Multicast))
+			if err != nil {
+				return err
+			}
+			defer c.Close()
+			topicMap[topic] = c
+		}
+
+		if err = c.Send(&transport.Message{
+			Header: msg.Header,
+			Body:   msg.Body,
+		}); err != nil {
+			//	msg.SetError(err)
+			return err
+		}
+	}
+
+	return nil
+}
+
 func (t *tunBroker) Publish(ctx context.Context, topic string, m *broker.Message, opts ...broker.PublishOption) error {
 	// TODO: this is probably inefficient, we might want to just maintain an open connection
 	// it may be easier to add broadcast to the tunnel
@@ -77,6 +117,26 @@ func (t *tunBroker) Publish(ctx context.Context, topic string, m *broker.Message
 	})
 }
 
+func (t *tunBroker) BatchSubscribe(ctx context.Context, topic string, h broker.BatchHandler, opts ...broker.SubscribeOption) (broker.Subscriber, error) {
+	l, err := t.tunnel.Listen(ctx, topic, tunnel.ListenMode(tunnel.Multicast))
+	if err != nil {
+		return nil, err
+	}
+
+	tunSub := &tunBatchSubscriber{
+		topic:    topic,
+		handler:  h,
+		opts:     broker.NewSubscribeOptions(opts...),
+		closed:   make(chan bool),
+		listener: l,
+	}
+
+	// start processing
+	go tunSub.run()
+
+	return tunSub, nil
+}
+
 func (t *tunBroker) Subscribe(ctx context.Context, topic string, h broker.Handler, opts ...broker.SubscribeOption) (broker.Subscriber, error) {
 	l, err := t.tunnel.Listen(ctx, topic, tunnel.ListenMode(tunnel.Multicast))
 	if err != nil {
@@ -101,6 +161,51 @@ func (t *tunBroker) String() string {
 	return "tunnel"
 }
 
+func (t *tunBatchSubscriber) run() {
+	for {
+		// accept a new connection
+		c, err := t.listener.Accept()
+		if err != nil {
+			select {
+			case <-t.closed:
+				return
+			default:
+				continue
+			}
+		}
+
+		// receive message
+		m := new(transport.Message)
+		if err := c.Recv(m); err != nil {
+			if logger.V(logger.ErrorLevel) {
+				logger.Error(t.opts.Context, err.Error())
+			}
+			if err = c.Close(); err != nil {
+				if logger.V(logger.ErrorLevel) {
+					logger.Error(t.opts.Context, err.Error())
+				}
+			}
+			continue
+		}
+
+		// close the connection
+		c.Close()
+
+		evts := broker.Events{&tunEvent{
+			topic: t.topic,
+			message: &broker.Message{
+				Header: m.Header,
+				Body:   m.Body,
+			},
+		}}
+		// handle the message
+		go func() {
+			_ = t.handler(evts)
+		}()
+
+	}
+}
+
 func (t *tunSubscriber) run() {
 	for {
 		// accept a new connection
@@ -132,13 +237,33 @@ func (t *tunSubscriber) run() {
 		c.Close()
 
 		// handle the message
-		go t.handler(&tunEvent{
-			topic: t.topic,
-			message: &broker.Message{
-				Header: m.Header,
-				Body:   m.Body,
-			},
-		})
+		go func() {
+			_ = t.handler(&tunEvent{
+				topic: t.topic,
+				message: &broker.Message{
+					Header: m.Header,
+					Body:   m.Body,
+				},
+			})
+		}()
+	}
+}
+
+func (t *tunBatchSubscriber) Options() broker.SubscribeOptions {
+	return t.opts
+}
+
+func (t *tunBatchSubscriber) Topic() string {
+	return t.topic
+}
+
+func (t *tunBatchSubscriber) Unsubscribe(ctx context.Context) error {
+	select {
+	case <-t.closed:
+		return nil
+	default:
+		close(t.closed)
+		return t.listener.Close()
 	}
 }
 
@@ -173,7 +298,11 @@ func (t *tunEvent) Ack() error {
 }
 
 func (t *tunEvent) Error() error {
-	return nil
+	return t.err
+}
+
+func (t *tunEvent) SetError(err error) {
+	t.err = err
 }
 
 // NewBroker returns new tunnel broker

network/tunnel/options.go

@@ -3,11 +3,11 @@ package tunnel
 import (
 	"time"
 
-	"github.com/google/uuid"
 	"github.com/unistack-org/micro/v3/logger"
 	"github.com/unistack-org/micro/v3/meter"
 	"github.com/unistack-org/micro/v3/network/transport"
 	"github.com/unistack-org/micro/v3/tracer"
+	"github.com/unistack-org/micro/v3/util/id"
 )
 
 var (
@@ -164,7 +164,7 @@ func DialWait(b bool) DialOption {
 // NewOptions returns router default options with filled values
 func NewOptions(opts ...Option) Options {
 	options := Options{
-		ID:      uuid.New().String(),
+		ID:      id.Must(),
 		Address: DefaultAddress,
 		Token:   DefaultToken,
 		Logger:  logger.DefaultLogger,

network/tunnel/transport/transport.go

@@ -37,7 +37,7 @@ func (t *tunTransport) Init(opts ...transport.Option) error {
 	// get the transport
 	tr, ok := t.options.Context.Value(transportKey{}).(transport.Transport)
 	if ok {
-		tun.Init(tunnel.Transport(tr))
+		_ = tun.Init(tunnel.Transport(tr))
 	}
 
 	// set the tunnel

profiler/pprof/pprof.go

@@ -31,7 +31,7 @@ func (p *profiler) writeHeap(f *os.File) {
 		select {
 		case <-t.C:
 			runtime.GC()
-			pprof.WriteHeapProfile(f)
+			_ = pprof.WriteHeapProfile(f)
 		case <-p.exit:
 			return
 		}

register/memory.go

@@ -6,8 +6,8 @@ import (
 	"sync"
 	"time"
 
-	"github.com/google/uuid"
 	"github.com/unistack-org/micro/v3/logger"
+	"github.com/unistack-org/micro/v3/util/id"
 )
 
 var (
@@ -378,13 +378,16 @@ func (m *memory) ListServices(ctx context.Context, opts ...ListOption) ([]*Servi
 }
 
 func (m *memory) Watch(ctx context.Context, opts ...WatchOption) (Watcher, error) {
+	id, err := id.New()
+	if err != nil {
+		return nil, err
+	}
 	wo := NewWatchOptions(opts...)
-
 	// construct the watcher
 	w := &watcher{
 		exit: make(chan bool),
 		res:  make(chan *Result),
-		id:   uuid.New().String(),
+		id:   id,
 		wo:   wo,
 	}
 

register/options.go

@@ -44,7 +44,7 @@ func NewOptions(opts ...Option) Options {
 	return options
 }
 
-// nolint: golint
+// nolint: golint,revive
 // RegisterOptions holds options for register method
 type RegisterOptions struct {
 	Context  context.Context
@@ -197,7 +197,7 @@ func TLSConfig(t *tls.Config) Option {
 	}
 }
 
-// nolint: golint
+// nolint: golint,revive
 // RegisterAttempts specifies register atempts count
 func RegisterAttempts(t int) RegisterOption {
 	return func(o *RegisterOptions) {
@@ -205,7 +205,7 @@ func RegisterAttempts(t int) RegisterOption {
 	}
 }
 
-// nolint: golint
+// nolint: golint,revive
 // RegisterTTL specifies register ttl
 func RegisterTTL(t time.Duration) RegisterOption {
 	return func(o *RegisterOptions) {
@@ -213,7 +213,7 @@ func RegisterTTL(t time.Duration) RegisterOption {
 	}
 }
 
-// nolint: golint
+// nolint: golint,revive
 // RegisterContext sets the register context
 func RegisterContext(ctx context.Context) RegisterOption {
 	return func(o *RegisterOptions) {
@@ -221,7 +221,7 @@ func RegisterContext(ctx context.Context) RegisterOption {
 	}
 }
 
-// nolint: golint
+// nolint: golint,revive
 // RegisterDomain secifies register domain
 func RegisterDomain(d string) RegisterOption {
 	return func(o *RegisterOptions) {

register/register.go

@@ -68,8 +68,8 @@ type Endpoint struct {
 // Option func signature
 type Option func(*Options)
 
+// nolint: golint,revive
 // RegisterOption option is used to register service
-// nolint: golint
 type RegisterOption func(*RegisterOptions)
 
 // WatchOption option is used to watch service changes

resolver/http/http.go

@@ -11,6 +11,7 @@ import (
 	"github.com/unistack-org/micro/v3/resolver"
 )
 
+// nolint: golint,revive
 // HTTPResolver is a HTTP network resolver
 type HTTPResolver struct {
 	// Proto if not set, defaults to http
@@ -53,6 +54,7 @@ func (r *HTTPResolver) Resolve(name string) ([]*resolver.Record, error) {
 	q.Set("name", name)
 	uri.RawQuery = q.Encode()
 
+	// nolint: noctx
 	rsp, err := http.Get(uri.String())
 	if err != nil {
 		return nil, err

router/dns.go

@@ -40,8 +40,9 @@ func (d *dns) Lookup(opts ...QueryOption) ([]Route, error) {
 	// check to see if we have the port provided in the service, e.g. go-micro-srv-foo:8000
 	host, port, err := net.SplitHostPort(options.Service)
 	if err == nil {
+		var ips []string
 		// lookup the service using A records
-		ips, err := net.LookupHost(host)
+		ips, err = net.LookupHost(host)
 		if err != nil {
 			return nil, err
 		}
@@ -53,7 +54,7 @@ func (d *dns) Lookup(opts ...QueryOption) ([]Route, error) {
 		for i, ip := range ips {
 			result[i] = Route{
 				Service: options.Service,
-				Address: fmt.Sprintf("%s:%d", ip, uint16(p)),
+				Address: fmt.Sprintf("%s:%d", ip, p),
 			}
 		}
 		return result, nil

router/options.go

@@ -3,9 +3,9 @@ package router
 import (
 	"context"
 
-	"github.com/google/uuid"
 	"github.com/unistack-org/micro/v3/logger"
 	"github.com/unistack-org/micro/v3/register"
+	"github.com/unistack-org/micro/v3/util/id"
 )
 
 // Options are router options
@@ -16,15 +16,15 @@ type Options struct {
 	Name     string
 	Gateway  string
 	Network  string
-	Id       string
+	ID       string
 	Address  string
 	Precache bool
 }
 
-// Id sets Router Id
-func Id(id string) Option {
+// ID sets Router Id
+func ID(id string) Option {
 	return func(o *Options) {
-		o.Id = id
+		o.ID = id
 	}
 }
 
@@ -80,7 +80,7 @@ func Name(n string) Option {
 // NewOptions returns router default options
 func NewOptions(opts ...Option) Options {
 	options := Options{
-		Id:       uuid.New().String(),
+		ID:       id.Must(),
 		Network:  DefaultNetwork,
 		Register: register.DefaultRegister,
 		Logger:   logger.DefaultLogger,

router/watcher.go

@@ -38,8 +38,8 @@ func (t EventType) String() string {
 type Event struct {
 	// Timestamp is event timestamp
 	Timestamp time.Time
-	// Id of the event
-	Id string
+	// ID of the event
+	ID string
 	// Route is table route
 	Route Route
 	// Type defines type of event

server/errors_test.go

@@ -13,7 +13,7 @@ func TestError(t *testing.T) {
 	if !ok {
 		t.Fatal("error not *errors.Error")
 	}
-	if merr.Id != "svc1" {
+	if merr.ID != "svc1" {
 		t.Fatal("id != svc1")
 	}
 }

server/generate.go

@@ -1,3 +1,12 @@
 package server
 
-//go:generate protoc -I./health -I../ -I/home/vtolstov/.cache/go-path/pkg/mod/github.com/unistack-org/micro-proto@v0.0.1 --micro_out=components=micro|http|server,standalone=false,debug=true,paths=source_relative:./health health/health.proto
+//go:generate sh -c "protoc -I./health -I../ -I$(go list -f '{{ .Dir }}' -m github.com/unistack-org/micro-proto) --go-micro_out='components=micro|http|server',standalone=false,debug=true,paths=source_relative:./health health/health.proto"
+
+import (
+
+	// import required packages
+	_ "github.com/unistack-org/micro-proto/api"
+
+	// import required packages
+	_ "github.com/unistack-org/micro-proto/openapiv2"
+)

server/health/health.proto

@@ -11,51 +11,51 @@ service Health {
 	rpc Live(micro.codec.Frame) returns (micro.codec.Frame) {
 		option (micro.openapiv2.openapiv2_operation) = {
       operation_id: "Live";
-        responses: {
-          key: "default";
+      responses: {
+        response_code: {
+          name: "default";
           value: {
-            description: "Error response";
-            schema: {
-              json_schema: {
-                ref: "micro.codec.Frame";
-              }
-            }
-          }
-        }
+            json_reference: {
+              description: "Error response";
+              _ref: "micro.codec.Frame";
+            };
+          };
+        };
+      };
     };
 		option (micro.api.http) = { get: "/live"; };
   };
 	rpc Ready(micro.codec.Frame) returns (micro.codec.Frame) {
 		option (micro.openapiv2.openapiv2_operation) = {
       operation_id: "Ready";
-        responses: {
-          key: "default";
+      responses: {
+        response_code: {
+          name: "default";
           value: {
-            description: "Error response";
-            schema: {
-              json_schema: {
-                ref: "micro.codec.Frame";
-              }
-            }
-          }
-        }
+            json_reference: {
+              description: "Error response";
+              _ref: "micro.codec.Frame";
+            };
+          };
+        };
+      };
     };
 		option (micro.api.http) = { get: "/ready"; };
   };
 	rpc Version(micro.codec.Frame) returns (micro.codec.Frame) {
 		option (micro.openapiv2.openapiv2_operation) = {
       operation_id: "Version";
-        responses: {
-          key: "default";
+      responses: {
+        response_code: {
+          name: "default";
           value: {
-            description: "Error response";
-            schema: {
-              json_schema: {
-                ref: "micro.codec.Frame";
-              }
-            }
-          }
-        }
+            json_reference: {
+              description: "Error response";
+              _ref: "micro.codec.Frame";
+            };
+          };
+        };
+      };
     };
 		option (micro.api.http) = { get: "/version"; };
   };

server/health/health_micro.pb.go

@@ -1,34 +1,43 @@
-// Code generated by protoc-gen-micro
+// Code generated by protoc-gen-go-micro. DO NOT EDIT.
+// protoc-gen-go-micro version: v3.4.2
 // source: health.proto
+
 package health
 
 import (
 	context "context"
+
 	api "github.com/unistack-org/micro/v3/api"
 	codec "github.com/unistack-org/micro/v3/codec"
 )
 
-func NewHealthEndpoints() []*api.Endpoint {
-	return []*api.Endpoint{
-		&api.Endpoint{
+var (
+	HealthName = "Health"
+
+	HealthEndpoints = []api.Endpoint{
+		{
 			Name:    "Health.Live",
 			Path:    []string{"/live"},
 			Method:  []string{"GET"},
 			Handler: "rpc",
 		},
-		&api.Endpoint{
+		{
 			Name:    "Health.Ready",
 			Path:    []string{"/ready"},
 			Method:  []string{"GET"},
 			Handler: "rpc",
 		},
-		&api.Endpoint{
+		{
 			Name:    "Health.Version",
 			Path:    []string{"/version"},
 			Method:  []string{"GET"},
 			Handler: "rpc",
 		},
 	}
+)
+
+func NewHealthEndpoints() []api.Endpoint {
+	return HealthEndpoints
 }
 
 type HealthServer interface {

server/health/health_micro_http.pb.go

@@ -1,9 +1,12 @@
-// Code generated by protoc-gen-micro
+// Code generated by protoc-gen-go-micro. DO NOT EDIT.
+// protoc-gen-go-micro version: v3.4.2
 // source: health.proto
+
 package health
 
 import (
 	context "context"
+
 	api "github.com/unistack-org/micro/v3/api"
 	codec "github.com/unistack-org/micro/v3/codec"
 	server "github.com/unistack-org/micro/v3/server"
@@ -36,8 +39,8 @@ func RegisterHealthServer(s server.Server, sh HealthServer, opts ...server.Handl
 	}
 	h := &healthServer{sh}
 	var nopts []server.HandlerOption
-	for _, endpoint := range NewHealthEndpoints() {
-		nopts = append(nopts, api.WithEndpoint(endpoint))
+	for _, endpoint := range HealthEndpoints {
+		nopts = append(nopts, api.WithEndpoint(&endpoint))
 	}
 	return s.Handle(s.NewHandler(&Health{h}, append(nopts, opts...)...))
 }

server/noop.go

@@ -6,11 +6,13 @@ import (
 	"sync"
 	"time"
 
-	//	cprotorpc "github.com/unistack-org/micro-codec-protorpc"
 	"github.com/unistack-org/micro/v3/broker"
 	"github.com/unistack-org/micro/v3/codec"
 	"github.com/unistack-org/micro/v3/logger"
 	"github.com/unistack-org/micro/v3/register"
+	maddr "github.com/unistack-org/micro/v3/util/addr"
+	mnet "github.com/unistack-org/micro/v3/util/net"
+	"github.com/unistack-org/micro/v3/util/rand"
 )
 
 // DefaultCodecs will be used to encode/decode
@@ -73,8 +75,7 @@ func (n *noopServer) Subscribe(sb Subscriber) error {
 	sub, ok := sb.(*subscriber)
 	if !ok {
 		return fmt.Errorf("invalid subscriber: expected *subscriber")
-	}
-	if len(sub.handlers) == 0 {
+	} else if len(sub.handlers) == 0 {
 		return fmt.Errorf("invalid subscriber: no handler functions")
 	}
 
@@ -107,11 +108,12 @@ func (n *noopServer) Init(opts ...Option) error {
 	}
 
 	if n.handlers == nil {
-		n.handlers = make(map[string]Handler)
+		n.handlers = make(map[string]Handler, 1)
 	}
 	if n.subscribers == nil {
-		n.subscribers = make(map[*subscriber][]broker.Subscriber)
+		n.subscribers = make(map[*subscriber][]broker.Subscriber, 1)
 	}
+
 	if n.exit == nil {
 		n.exit = make(chan chan error)
 	}
@@ -188,7 +190,7 @@ func (n *noopServer) Register() error {
 	}
 
 	// register the service
-	if err := DefaultRegisterFunc(service, config); err != nil {
+	if err = DefaultRegisterFunc(service, config); err != nil {
 		return err
 	}
 
@@ -202,26 +204,34 @@ func (n *noopServer) Register() error {
 
 	cx := config.Context
 
-	for sb := range n.subscribers {
-		handler := n.createSubHandler(sb, config)
-		var opts []broker.SubscribeOption
-		if queue := sb.Options().Queue; len(queue) > 0 {
-			opts = append(opts, broker.SubscribeGroup(queue))
-		}
+	var sub broker.Subscriber
 
+	for sb := range n.subscribers {
 		if sb.Options().Context != nil {
 			cx = sb.Options().Context
 		}
 
-		opts = append(opts, broker.SubscribeContext(cx), broker.SubscribeAutoAck(sb.Options().AutoAck))
+		opts := []broker.SubscribeOption{broker.SubscribeContext(cx), broker.SubscribeAutoAck(sb.Options().AutoAck)}
+		if queue := sb.Options().Queue; len(queue) > 0 {
+			opts = append(opts, broker.SubscribeGroup(queue))
+		}
+
+		if sb.Options().Batch {
+			// batch processing handler
+			sub, err = config.Broker.BatchSubscribe(cx, sb.Topic(), n.newBatchSubHandler(sb, config), opts...)
+		} else {
+			// single processing handler
+			sub, err = config.Broker.Subscribe(cx, sb.Topic(), n.newSubHandler(sb, config), opts...)
+		}
+
+		if err != nil {
+			return err
+		}
 
 		if config.Logger.V(logger.InfoLevel) {
 			config.Logger.Infof(n.opts.Context, "subscribing to topic: %s", sb.Topic())
 		}
-		sub, err := config.Broker.Subscribe(cx, sb.Topic(), handler, opts...)
-		if err != nil {
-			return err
-		}
+
 		n.subscribers[sb] = []broker.Subscriber{sub}
 	}
 
@@ -303,9 +313,22 @@ func (n *noopServer) Start() error {
 	config := n.Options()
 	n.RUnlock()
 
+	// 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)
+
+	config.Address = addr
+
 	if config.Logger.V(logger.InfoLevel) {
 		config.Logger.Infof(n.opts.Context, "server [noop] Listening on %s", config.Address)
 	}
+
 	n.Lock()
 	if len(config.Advertise) == 0 {
 		config.Advertise = config.Address

server/noop_test.go

@@ -0,0 +1,102 @@
+package server_test
+
+import (
+	"context"
+	"fmt"
+	"testing"
+
+	"github.com/unistack-org/micro/v3/broker"
+	"github.com/unistack-org/micro/v3/client"
+	"github.com/unistack-org/micro/v3/codec"
+	"github.com/unistack-org/micro/v3/metadata"
+	"github.com/unistack-org/micro/v3/server"
+)
+
+type TestHandler struct {
+	t *testing.T
+}
+
+type TestMessage struct {
+	Name string
+}
+
+func (h *TestHandler) SingleSubHandler(ctx context.Context, msg *codec.Frame) error {
+	// fmt.Printf("msg %s\n", msg.Data)
+	return nil
+}
+
+func (h *TestHandler) BatchSubHandler(ctxs []context.Context, msgs []*codec.Frame) error {
+	if len(msgs) != 8 {
+		h.t.Fatal("invalid number of messages received")
+	}
+	for idx := 0; idx < len(msgs); idx++ {
+		md, _ := metadata.FromIncomingContext(ctxs[idx])
+		_ = md
+		//	fmt.Printf("msg md %v\n", md)
+	}
+	return nil
+}
+
+func TestNoopSub(t *testing.T) {
+	ctx := context.Background()
+
+	b := broker.NewBroker()
+
+	if err := b.Init(); err != nil {
+		t.Fatal(err)
+	}
+
+	if err := b.Connect(ctx); err != nil {
+		t.Fatal(err)
+	}
+
+	s := server.NewServer(
+		server.Broker(b),
+		server.Codec("application/octet-stream", codec.NewCodec()),
+	)
+	if err := s.Init(); err != nil {
+		t.Fatal(err)
+	}
+
+	c := client.NewClient(
+		client.Broker(b),
+		client.Codec("application/octet-stream", codec.NewCodec()),
+		client.ContentType("application/octet-stream"),
+	)
+	if err := c.Init(); err != nil {
+		t.Fatal(err)
+	}
+	h := &TestHandler{t: t}
+
+	if err := s.Subscribe(s.NewSubscriber("single_topic", h.SingleSubHandler,
+		server.SubscriberQueue("queue"),
+	)); err != nil {
+		t.Fatal(err)
+	}
+
+	if err := s.Subscribe(s.NewSubscriber("batch_topic", h.BatchSubHandler,
+		server.SubscriberQueue("queue"),
+		server.SubscriberBatch(true),
+	)); err != nil {
+		t.Fatal(err)
+	}
+
+	if err := s.Start(); err != nil {
+		t.Fatal(err)
+	}
+
+	msgs := make([]client.Message, 0, 8)
+	for i := 0; i < 8; i++ {
+		msgs = append(msgs, c.NewMessage("batch_topic", &codec.Frame{Data: []byte(fmt.Sprintf(`{"name": "test_name %d"}`, i))}))
+	}
+
+	if err := c.BatchPublish(ctx, msgs); err != nil {
+		t.Fatal(err)
+	}
+
+	defer func() {
+		if err := s.Stop(); err != nil {
+			t.Fatal(err)
+		}
+	}()
+}

server/options.go

@@ -71,6 +71,8 @@ type Options struct {
 	Version string
 	// SubWrappers holds the server subscribe wrappers
 	SubWrappers []SubscriberWrapper
+	// BatchSubWrappers holds the server batch subscribe wrappers
+	BatchSubWrappers []BatchSubscriberWrapper
 	// HdlrWrappers holds the handler wrappers
 	HdlrWrappers []HandlerWrapper
 	// RegisterAttempts holds the number of register attempts before error
@@ -260,7 +262,7 @@ func TLSConfig(t *tls.Config) Option {
 		// already set. Required for Init call below.
 
 		// set the transport tls
-		o.Transport.Init(
+		_ = o.Transport.Init(
 			transport.TLSConfig(t),
 		)
 	}
@@ -302,6 +304,13 @@ func WrapSubscriber(w SubscriberWrapper) Option {
 	}
 }
 
+// WrapBatchSubscriber adds a batch subscriber Wrapper to a list of options passed into the server
+func WrapBatchSubscriber(w BatchSubscriberWrapper) Option {
+	return func(o *Options) {
+		o.BatchSubWrappers = append(o.BatchSubWrappers, w)
+	}
+}
+
 // MaxConn specifies maximum number of max simultaneous connections to server
 func MaxConn(n int) Option {
 	return func(o *Options) {
@@ -354,6 +363,12 @@ type SubscriberOptions struct {
 	AutoAck bool
 	// BodyOnly flag specifies that message without headers
 	BodyOnly bool
+	// Batch flag specifies that message processed in batches
+	Batch bool
+	// BatchSize flag specifies max size of batch
+	BatchSize int
+	// BatchWait flag specifies max wait time for batch filling
+	BatchWait time.Duration
 }
 
 // NewSubscriberOptions create new SubscriberOptions
@@ -413,3 +428,32 @@ func SubscriberContext(ctx context.Context) SubscriberOption {
 		o.Context = ctx
 	}
 }
+
+// SubscriberAck control auto ack processing for handler
+func SubscriberAck(b bool) SubscriberOption {
+	return func(o *SubscriberOptions) {
+		o.AutoAck = b
+	}
+}
+
+// SubscriberBatch control batch processing for handler
+func SubscriberBatch(b bool) SubscriberOption {
+	return func(o *SubscriberOptions) {
+		o.Batch = b
+	}
+}
+
+// SubscriberBatchSize control batch filling size for handler
+// Batch filling max waiting time controlled by SubscriberBatchWait
+func SubscriberBatchSize(n int) SubscriberOption {
+	return func(o *SubscriberOptions) {
+		o.BatchSize = n
+	}
+}
+
+// SubscriberBatchWait control batch filling wait time for handler
+func SubscriberBatchWait(td time.Duration) SubscriberOption {
+	return func(o *SubscriberOptions) {
+		o.BatchWait = td
+	}
+}

server/server.go

@@ -5,24 +5,24 @@ import (
 	"context"
 	"time"
 
-	"github.com/google/uuid"
 	"github.com/unistack-org/micro/v3/codec"
 	"github.com/unistack-org/micro/v3/metadata"
 	"github.com/unistack-org/micro/v3/register"
+	"github.com/unistack-org/micro/v3/util/id"
 )
 
 // DefaultServer default server
 var DefaultServer Server = NewServer()
 
 var (
-	// DefaultAddress will be used if no address passed
-	DefaultAddress = ":0"
+	// DefaultAddress will be used if no address passed, use secure localhost
+	DefaultAddress = "127.0.0.1:0"
 	// DefaultName will be used if no name passed
 	DefaultName = "server"
 	// DefaultVersion will be used if no version passed
 	DefaultVersion = "latest"
 	// DefaultID will be used if no id passed
-	DefaultID = uuid.New().String()
+	DefaultID = id.Must()
 	// DefaultRegisterCheck holds func that run before register server
 	DefaultRegisterCheck = func(context.Context) error { return nil }
 	// DefaultRegisterInterval holds interval for register

server/subscriber.go

@@ -11,6 +11,7 @@ import (
 	"unicode/utf8"
 
 	"github.com/unistack-org/micro/v3/broker"
+	"github.com/unistack-org/micro/v3/codec"
 	"github.com/unistack-org/micro/v3/errors"
 	"github.com/unistack-org/micro/v3/logger"
 	"github.com/unistack-org/micro/v3/metadata"
@@ -18,7 +19,8 @@ import (
 )
 
 const (
-	subSig = "func(context.Context, interface{}) error"
+	subSig      = "func(context.Context, interface{}) error"
+	batchSubSig = "func([]context.Context, []interface{}) error"
 )
 
 // Precompute the reflect type for error. Can't use error directly
@@ -32,13 +34,13 @@ type handler struct {
 }
 
 type subscriber struct {
-	opts       SubscriberOptions
 	typ        reflect.Type
 	subscriber interface{}
 	rcvr       reflect.Value
 	topic      string
-	handlers   []*handler
 	endpoints  []*register.Endpoint
+	handlers   []*handler
+	opts       SubscriberOptions
 }
 
 // Is this an exported - upper case - name?
@@ -57,26 +59,33 @@ func isExportedOrBuiltinType(t reflect.Type) bool {
 	return isExported(t.Name()) || t.PkgPath() == ""
 }
 
-// ValidateSubscriber func
+// ValidateSubscriber func signature
 func ValidateSubscriber(sub Subscriber) error {
 	typ := reflect.TypeOf(sub.Subscriber())
 	var argType reflect.Type
-
 	switch typ.Kind() {
 	case reflect.Func:
 		name := "Func"
 		switch typ.NumIn() {
 		case 2:
 			argType = typ.In(1)
+			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", name, typ.NumIn(), subSig)
+			return fmt.Errorf("subscriber %v takes wrong number of args: %v required signature %s or %s", name, typ.NumIn(), subSig, batchSubSig)
 		}
 		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 outs: %v require signature %s",
-				name, typ.NumOut(), subSig)
+			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())
@@ -87,13 +96,12 @@ func ValidateSubscriber(sub Subscriber) error {
 
 		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",
-					name, method.Name, method.Type.NumIn(), subSig)
+				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) {
@@ -101,8 +109,8 @@ func ValidateSubscriber(sub Subscriber) error {
 			}
 			if method.Type.NumOut() != 1 {
 				return fmt.Errorf(
-					"subscriber %v.%v has wrong number of outs: %v require signature %s",
-					name, method.Name, method.Type.NumOut(), subSig)
+					"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())
@@ -183,7 +191,125 @@ func newSubscriber(topic string, sub interface{}, opts ...SubscriberOption) Subs
 }
 
 //nolint:gocyclo
-func (n *noopServer) createSubHandler(sb *subscriber, opts Options) broker.Handler {
+func (n *noopServer) newBatchSubHandler(sb *subscriber, opts Options) broker.BatchHandler {
+	return func(ps broker.Events) (err error) {
+		defer func() {
+			if r := recover(); r != nil {
+				n.RLock()
+				config := n.opts
+				n.RUnlock()
+				if config.Logger.V(logger.ErrorLevel) {
+					config.Logger.Error(n.opts.Context, "panic recovered: ", r)
+					config.Logger.Error(n.opts.Context, string(debug.Stack()))
+				}
+				err = errors.InternalServerError(n.opts.Name+".subscriber", "panic recovered: %v", r)
+			}
+		}()
+
+		msgs := make([]Message, 0, len(ps))
+		ctxs := make([]context.Context, 0, len(ps))
+		for _, p := range ps {
+			msg := p.Message()
+			// if we don't have headers, create empty map
+			if msg.Header == nil {
+				msg.Header = metadata.New(2)
+			}
+
+			ct, _ := msg.Header.Get(metadata.HeaderContentType)
+			if len(ct) == 0 {
+				msg.Header.Set(metadata.HeaderContentType, defaultContentType)
+				ct = defaultContentType
+			}
+			hdr := metadata.Copy(msg.Header)
+			topic, _ := msg.Header.Get(metadata.HeaderTopic)
+			ctxs = append(ctxs, metadata.NewIncomingContext(sb.opts.Context, hdr))
+			msgs = append(msgs, &rpcMessage{
+				topic:       topic,
+				contentType: ct,
+				header:      msg.Header,
+				body:        msg.Body,
+			})
+		}
+		results := make(chan error, len(sb.handlers))
+
+		for i := 0; i < len(sb.handlers); i++ {
+			handler := sb.handlers[i]
+
+			var req reflect.Value
+
+			switch handler.reqType.Kind() {
+			case reflect.Ptr:
+				req = reflect.New(handler.reqType.Elem())
+			default:
+				req = reflect.New(handler.reqType.Elem()).Elem()
+			}
+
+			reqType := handler.reqType
+			var cf codec.Codec
+			for _, msg := range msgs {
+				cf, err = n.newCodec(msg.ContentType())
+				if err != nil {
+					return err
+				}
+				rb := reflect.New(req.Type().Elem())
+				if err = cf.ReadBody(bytes.NewReader(msg.Body()), rb.Interface()); err != nil {
+					return err
+				}
+				msg.(*rpcMessage).codec = cf
+				msg.(*rpcMessage).payload = rb.Interface()
+			}
+
+			fn := func(ctxs []context.Context, ms []Message) error {
+				var vals []reflect.Value
+				if sb.typ.Kind() != reflect.Func {
+					vals = append(vals, sb.rcvr)
+				}
+				if handler.ctxType != nil {
+					vals = append(vals, reflect.ValueOf(ctxs))
+				}
+				payloads := reflect.MakeSlice(reqType, 0, len(ms))
+				for _, m := range ms {
+					payloads = reflect.Append(payloads, reflect.ValueOf(m.Payload()))
+				}
+				vals = append(vals, payloads)
+
+				returnValues := handler.method.Call(vals)
+				if rerr := returnValues[0].Interface(); rerr != nil {
+					return rerr.(error)
+				}
+				return nil
+			}
+
+			for i := len(opts.BatchSubWrappers); i > 0; i-- {
+				fn = opts.BatchSubWrappers[i-1](fn)
+			}
+
+			if n.wg != nil {
+				n.wg.Add(1)
+			}
+			go func() {
+				if n.wg != nil {
+					defer n.wg.Done()
+				}
+				results <- fn(ctxs, msgs)
+			}()
+		}
+
+		var errors []string
+		for i := 0; i < len(sb.handlers); i++ {
+			if rerr := <-results; rerr != nil {
+				errors = append(errors, rerr.Error())
+			}
+		}
+		if len(errors) > 0 {
+			err = fmt.Errorf("subscriber error: %s", strings.Join(errors, "\n"))
+		}
+		return err
+	}
+}
+
+//nolint:gocyclo
+func (n *noopServer) newSubHandler(sb *subscriber, opts Options) broker.Handler {
 	return func(p broker.Event) (err error) {
 		defer func() {
 			if r := recover(); r != nil {
@@ -201,12 +327,12 @@ func (n *noopServer) createSubHandler(sb *subscriber, opts Options) broker.Handl
 		msg := p.Message()
 		// if we don't have headers, create empty map
 		if msg.Header == nil {
-			msg.Header = make(map[string]string)
+			msg.Header = metadata.New(2)
 		}
 
 		ct := msg.Header["Content-Type"]
 		if len(ct) == 0 {
-			msg.Header["Content-Type"] = defaultContentType
+			msg.Header.Set(metadata.HeaderContentType, defaultContentType)
 			ct = defaultContentType
 		}
 		cf, err := n.newCodec(ct)
@@ -214,12 +340,12 @@ func (n *noopServer) createSubHandler(sb *subscriber, opts Options) broker.Handl
 			return err
 		}
 
-		hdr := make(map[string]string, len(msg.Header))
+		hdr := metadata.New(len(msg.Header))
 		for k, v := range msg.Header {
 			if k == "Content-Type" {
 				continue
 			}
-			hdr[k] = v
+			hdr.Set(k, v)
 		}
 
 		ctx := metadata.NewIncomingContext(sb.opts.Context, hdr)
@@ -294,7 +420,6 @@ func (n *noopServer) createSubHandler(sb *subscriber, opts Options) broker.Handl
 		if len(errors) > 0 {
 			err = fmt.Errorf("subscriber error: %s", strings.Join(errors, "\n"))
 		}
-
 		return err
 	}
 }

server/wrapper.go

@@ -14,12 +14,20 @@ type HandlerFunc func(ctx context.Context, req Request, rsp interface{}) error
 // publication message.
 type SubscriberFunc func(ctx context.Context, msg Message) error
 
+// BatchSubscriberFunc represents a single method of a subscriber. It's used primarily
+// for the wrappers. What's handed to the actual method is the concrete
+// publication message. This func used by batch subscribers
+type BatchSubscriberFunc func(ctxs []context.Context, msgs []Message) error
+
 // HandlerWrapper wraps the HandlerFunc and returns the equivalent
 type HandlerWrapper func(HandlerFunc) HandlerFunc
 
 // SubscriberWrapper wraps the SubscriberFunc and returns the equivalent
 type SubscriberWrapper func(SubscriberFunc) SubscriberFunc
 
+// BatchSubscriberWrapper wraps the SubscriberFunc and returns the equivalent
+type BatchSubscriberWrapper func(BatchSubscriberFunc) BatchSubscriberFunc
+
 // StreamWrapper wraps a Stream interface and returns the equivalent.
 // Because streams exist for the lifetime of a method invocation this
 // is a convenient way to wrap a Stream as its in use for trace, monitoring,

store/memory.go

@@ -36,16 +36,6 @@ func (m *memoryStore) key(prefix, key string) string {
 	return filepath.Join(prefix, key)
 }
 
-func (m *memoryStore) prefix(database, table string) string {
-	if len(database) == 0 {
-		database = m.opts.Database
-	}
-	if len(table) == 0 {
-		table = m.opts.Table
-	}
-	return filepath.Join(database, table)
-}
-
 func (m *memoryStore) exists(prefix, key string) error {
 	key = m.key(prefix, key)
 
@@ -80,15 +70,17 @@ func (m *memoryStore) delete(prefix, key string) {
 
 func (m *memoryStore) list(prefix string, limit, offset uint) []string {
 	allItems := m.store.Items()
-	allKeys := make([]string, len(allItems))
-	i := 0
+	allKeys := make([]string, 0, len(allItems))
 
 	for k := range allItems {
-		if !strings.HasPrefix(k, prefix+"/") {
+		if !strings.HasPrefix(k, prefix) {
 			continue
 		}
-		allKeys[i] = strings.TrimPrefix(k, prefix+"/")
-		i++
+		k = strings.TrimPrefix(k, prefix)
+		if k[0] == '/' {
+			k = k[1:]
+		}
+		allKeys = append(allKeys, k)
 	}
 
 	if limit != 0 || offset != 0 {
@@ -107,7 +99,6 @@ func (m *memoryStore) list(prefix string, limit, offset uint) []string {
 		}
 		return allKeys[offset:end]
 	}
-
 	return allKeys
 }
 
@@ -127,37 +118,48 @@ func (m *memoryStore) Name() string {
 }
 
 func (m *memoryStore) Exists(ctx context.Context, key string, opts ...ExistsOption) error {
-	prefix := m.prefix(m.opts.Database, m.opts.Table)
-	return m.exists(prefix, key)
+	options := NewExistsOptions(opts...)
+	if options.Namespace == "" {
+		options.Namespace = m.opts.Namespace
+	}
+	return m.exists(options.Namespace, key)
 }
 
 func (m *memoryStore) Read(ctx context.Context, key string, val interface{}, opts ...ReadOption) error {
-	readOpts := NewReadOptions(opts...)
-	prefix := m.prefix(readOpts.Database, readOpts.Table)
-	return m.get(prefix, key, val)
+	options := NewReadOptions(opts...)
+	if options.Namespace == "" {
+		options.Namespace = m.opts.Namespace
+	}
+	return m.get(options.Namespace, key, val)
 }
 
 func (m *memoryStore) Write(ctx context.Context, key string, val interface{}, opts ...WriteOption) error {
-	writeOpts := NewWriteOptions(opts...)
+	options := NewWriteOptions(opts...)
+	if options.Namespace == "" {
+		options.Namespace = m.opts.Namespace
+	}
+	if options.TTL == 0 {
+		options.TTL = cache.NoExpiration
+	}
 
-	prefix := m.prefix(writeOpts.Database, writeOpts.Table)
-
-	key = m.key(prefix, key)
+	key = m.key(options.Namespace, key)
 
 	buf, err := m.opts.Codec.Marshal(val)
 	if err != nil {
 		return err
 	}
 
-	m.store.Set(key, buf, writeOpts.TTL)
+	m.store.Set(key, buf, options.TTL)
 	return nil
 }
 
 func (m *memoryStore) Delete(ctx context.Context, key string, opts ...DeleteOption) error {
-	deleteOptions := NewDeleteOptions(opts...)
+	options := NewDeleteOptions(opts...)
+	if options.Namespace == "" {
+		options.Namespace = m.opts.Namespace
+	}
 
-	prefix := m.prefix(deleteOptions.Database, deleteOptions.Table)
-	m.delete(prefix, key)
+	m.delete(options.Namespace, key)
 	return nil
 }
 
@@ -166,25 +168,27 @@ func (m *memoryStore) Options() Options {
 }
 
 func (m *memoryStore) List(ctx context.Context, opts ...ListOption) ([]string, error) {
-	listOptions := NewListOptions(opts...)
+	options := NewListOptions(opts...)
+	if options.Namespace == "" {
+		options.Namespace = m.opts.Namespace
+	}
 
-	prefix := m.prefix(listOptions.Database, listOptions.Table)
-	keys := m.list(prefix, listOptions.Limit, listOptions.Offset)
+	keys := m.list(options.Namespace, options.Limit, options.Offset)
 
-	if len(listOptions.Prefix) > 0 {
+	if len(options.Prefix) > 0 {
 		var prefixKeys []string
 		for _, k := range keys {
-			if strings.HasPrefix(k, listOptions.Prefix) {
+			if strings.HasPrefix(k, options.Prefix) {
 				prefixKeys = append(prefixKeys, k)
 			}
 		}
 		keys = prefixKeys
 	}
 
-	if len(listOptions.Suffix) > 0 {
+	if len(options.Suffix) > 0 {
 		var suffixKeys []string
 		for _, k := range keys {
-			if strings.HasSuffix(k, listOptions.Suffix) {
+			if strings.HasSuffix(k, options.Suffix) {
 				suffixKeys = append(suffixKeys, k)
 			}
 		}

store/memory_test.go

@@ -9,11 +9,11 @@ import (
 )
 
 func TestMemoryReInit(t *testing.T) {
-	s := store.NewStore(store.Table("aaa"))
-	if err := s.Init(store.Table("")); err != nil {
+	s := store.NewStore(store.Namespace("aaa"))
+	if err := s.Init(store.Namespace("")); err != nil {
 		t.Fatal(err)
 	}
-	if len(s.Options().Table) > 0 {
+	if len(s.Options().Namespace) > 0 {
 		t.Error("Init didn't reinitialise the store")
 	}
 }
@@ -28,7 +28,7 @@ func TestMemoryBasic(t *testing.T) {
 
 func TestMemoryPrefix(t *testing.T) {
 	s := store.NewStore()
-	if err := s.Init(store.Table("some-prefix")); err != nil {
+	if err := s.Init(store.Namespace("some-prefix")); err != nil {
 		t.Fatal(err)
 	}
 	basictest(s, t)
@@ -36,7 +36,7 @@ func TestMemoryPrefix(t *testing.T) {
 
 func TestMemoryNamespace(t *testing.T) {
 	s := store.NewStore()
-	if err := s.Init(store.Database("some-namespace")); err != nil {
+	if err := s.Init(store.Namespace("some-namespace")); err != nil {
 		t.Fatal(err)
 	}
 	basictest(s, t)
@@ -44,7 +44,7 @@ func TestMemoryNamespace(t *testing.T) {
 
 func TestMemoryNamespacePrefix(t *testing.T) {
 	s := store.NewStore()
-	if err := s.Init(store.Table("some-prefix"), store.Database("some-namespace")); err != nil {
+	if err := s.Init(store.Namespace("some-namespace")); err != nil {
 		t.Fatal(err)
 	}
 	basictest(s, t)

store/options.go

@@ -28,13 +28,12 @@ type Options struct {
 	TLSConfig *tls.Config
 	// Name specifies store name
 	Name string
-	// Database specifies store database
-	Database string
-	// Table specifies store table
-	Table string
-	// Nodes contains store address
-	// TODO: replace with Addrs
-	Nodes []string
+	// Namespace of the records
+	Namespace string
+	// Addrs contains store address
+	Addrs []string
+	// Wrappers store wrapper that called before actual functions
+	// Wrappers []Wrapper
 }
 
 // NewOptions creates options struct
@@ -90,13 +89,20 @@ func Meter(m meter.Meter) Option {
 	}
 }
 
-// Name the name
+// Name the name of the store
 func Name(n string) Option {
 	return func(o *Options) {
 		o.Name = n
 	}
 }
 
+// Namespace sets namespace of the store
+func Namespace(ns string) Option {
+	return func(o *Options) {
+		o.Namespace = ns
+	}
+}
+
 // Tracer sets the tracer
 func Tracer(t tracer.Tracer) Option {
 	return func(o *Options) {
@@ -104,27 +110,21 @@ func Tracer(t tracer.Tracer) Option {
 	}
 }
 
-// Nodes contains the addresses or other connection information of the backing storage.
+// Addrs contains the addresses or other connection information of the backing storage.
 // For example, an etcd implementation would contain the nodes of the cluster.
 // A SQL implementation could contain one or more connection strings.
-func Nodes(a ...string) Option {
+func Addrs(addrs ...string) Option {
 	return func(o *Options) {
-		o.Nodes = a
+		o.Addrs = addrs
 	}
 }
 
-// Database allows multiple isolated stores to be kept in one backend, if supported.
-func Database(db string) Option {
-	return func(o *Options) {
-		o.Database = db
-	}
-}
-
-// Table is analag for a table in database backends or a key prefix in KV backends
-func Table(t string) Option {
-	return func(o *Options) {
-		o.Table = t
-	}
+// ReadOptions configures an individual Read operation
+type ReadOptions struct {
+	// Context holds external options
+	Context context.Context
+	// Namespace holds namespace
+	Namespace string
 }
 
 // NewReadOptions fills ReadOptions struct with opts slice
@@ -136,29 +136,35 @@ func NewReadOptions(opts ...ReadOption) ReadOptions {
 	return options
 }
 
-// ReadOptions configures an individual Read operation
-type ReadOptions struct {
-	// Context holds external options
-	Context context.Context
-	// Database holds the database name
-	Database string
-	// Table holds table name
-	Table string
-	// Namespace holds namespace
-	Namespace string
-}
-
 // ReadOption sets values in ReadOptions
 type ReadOption func(r *ReadOptions)
 
-// ReadFrom the database and table
-func ReadFrom(database, table string) ReadOption {
-	return func(r *ReadOptions) {
-		r.Database = database
-		r.Table = table
+// ReadContext pass context.Context to ReadOptions
+func ReadContext(ctx context.Context) ReadOption {
+	return func(o *ReadOptions) {
+		o.Context = ctx
 	}
 }
 
+// ReadNamespace pass namespace to ReadOptions
+func ReadNamespace(ns string) ReadOption {
+	return func(o *ReadOptions) {
+		o.Namespace = ns
+	}
+}
+
+// WriteOptions configures an individual Write operation
+type WriteOptions struct {
+	// Context holds external options
+	Context context.Context
+	// Metadata contains additional metadata
+	Metadata metadata.Metadata
+	// Namespace holds namespace
+	Namespace string
+	// TTL specifies key TTL
+	TTL time.Duration
+}
+
 // NewWriteOptions fills WriteOptions struct with opts slice
 func NewWriteOptions(opts ...WriteOption) WriteOptions {
 	options := WriteOptions{}
@@ -168,47 +174,45 @@ func NewWriteOptions(opts ...WriteOption) WriteOptions {
 	return options
 }
 
-// WriteOptions configures an individual Write operation
-type WriteOptions struct {
-	// Context holds external options
-	Context context.Context
-	// Metadata contains additional metadata
-	Metadata metadata.Metadata
-	// Database holds database name
-	Database string
-	// Table holds table name
-	Table string
-	// Namespace holds namespace
-	Namespace string
-	// TTL specifies key TTL
-	TTL time.Duration
-}
-
 // WriteOption sets values in WriteOptions
 type WriteOption func(w *WriteOptions)
 
-// WriteTo the database and table
-func WriteTo(database, table string) WriteOption {
-	return func(w *WriteOptions) {
-		w.Database = database
-		w.Table = table
-	}
-}
-
-// WriteTTL is the time the record expires
-func WriteTTL(d time.Duration) WriteOption {
-	return func(w *WriteOptions) {
-		w.TTL = d
+// WriteContext pass context.Context to wirte options
+func WriteContext(ctx context.Context) WriteOption {
+	return func(o *WriteOptions) {
+		o.Context = ctx
 	}
 }
 
 // WriteMetadata add metadata.Metadata
 func WriteMetadata(md metadata.Metadata) WriteOption {
-	return func(w *WriteOptions) {
-		w.Metadata = metadata.Copy(md)
+	return func(o *WriteOptions) {
+		o.Metadata = metadata.Copy(md)
 	}
 }
 
+// WriteTTL is the time the record expires
+func WriteTTL(d time.Duration) WriteOption {
+	return func(o *WriteOptions) {
+		o.TTL = d
+	}
+}
+
+// WriteNamespace pass namespace to write options
+func WriteNamespace(ns string) WriteOption {
+	return func(o *WriteOptions) {
+		o.Namespace = ns
+	}
+}
+
+// DeleteOptions configures an individual Delete operation
+type DeleteOptions struct {
+	// Context holds external options
+	Context context.Context
+	// Namespace holds namespace
+	Namespace string
+}
+
 // NewDeleteOptions fills DeleteOptions struct with opts slice
 func NewDeleteOptions(opts ...DeleteOption) DeleteOptions {
 	options := DeleteOptions{}
@@ -218,29 +222,33 @@ func NewDeleteOptions(opts ...DeleteOption) DeleteOptions {
 	return options
 }
 
-// DeleteOptions configures an individual Delete operation
-type DeleteOptions struct {
-	// Context holds external options
-	Context context.Context
-	// Database holds database name
-	Database string
-	// Table holds table name
-	Table string
-	// Namespace holds namespace
-	Namespace string
-}
-
 // DeleteOption sets values in DeleteOptions
 type DeleteOption func(d *DeleteOptions)
 
-// DeleteFrom the database and table
-func DeleteFrom(database, table string) DeleteOption {
-	return func(d *DeleteOptions) {
-		d.Database = database
-		d.Table = table
+// DeleteContext pass context.Context to delete options
+func DeleteContext(ctx context.Context) DeleteOption {
+	return func(o *DeleteOptions) {
+		o.Context = ctx
 	}
 }
 
+// DeleteNamespace pass namespace to delete options
+func DeleteNamespace(ns string) DeleteOption {
+	return func(o *DeleteOptions) {
+		o.Namespace = ns
+	}
+}
+
+// ListOptions configures an individual List operation
+type ListOptions struct {
+	Context   context.Context
+	Prefix    string
+	Suffix    string
+	Namespace string
+	Limit     uint
+	Offset    uint
+}
+
 // NewListOptions fills ListOptions struct with opts slice
 func NewListOptions(opts ...ListOption) ListOptions {
 	options := ListOptions{}
@@ -250,59 +258,50 @@ func NewListOptions(opts ...ListOption) ListOptions {
 	return options
 }
 
-// ListOptions configures an individual List operation
-type ListOptions struct {
-	Context   context.Context
-	Database  string
-	Prefix    string
-	Suffix    string
-	Namespace string
-	Table     string
-	Limit     uint
-	Offset    uint
-}
-
 // ListOption sets values in ListOptions
 type ListOption func(l *ListOptions)
 
-// ListFrom the database and table
-func ListFrom(database, table string) ListOption {
-	return func(l *ListOptions) {
-		l.Database = database
-		l.Table = table
+// ListContext pass context.Context to list options
+func ListContext(ctx context.Context) ListOption {
+	return func(o *ListOptions) {
+		o.Context = ctx
 	}
 }
 
 // ListPrefix returns all keys that are prefixed with key
-func ListPrefix(p string) ListOption {
-	return func(l *ListOptions) {
-		l.Prefix = p
+func ListPrefix(s string) ListOption {
+	return func(o *ListOptions) {
+		o.Prefix = s
 	}
 }
 
 // ListSuffix returns all keys that end with key
 func ListSuffix(s string) ListOption {
-	return func(l *ListOptions) {
-		l.Suffix = s
+	return func(o *ListOptions) {
+		o.Suffix = s
 	}
 }
 
-// ListLimit limits the number of returned keys to l
-func ListLimit(l uint) ListOption {
-	return func(lo *ListOptions) {
-		lo.Limit = l
+// ListLimit limits the number of returned keys
+func ListLimit(n uint) ListOption {
+	return func(o *ListOptions) {
+		o.Limit = n
 	}
 }
 
-// ListOffset starts returning responses from o. Use in conjunction with Limit for pagination.
-func ListOffset(o uint) ListOption {
-	return func(l *ListOptions) {
-		l.Offset = o
+// ListOffset use with Limit for pagination
+func ListOffset(n uint) ListOption {
+	return func(o *ListOptions) {
+		o.Offset = n
 	}
 }
 
-// ExistsOption specifies Exists call options
-type ExistsOption func(*ExistsOptions)
+// ListNamespace pass namespace to list options
+func ListNamespace(ns string) ListOption {
+	return func(o *ListOptions) {
+		o.Namespace = ns
+	}
+}
 
 // ExistsOptions holds options for Exists method
 type ExistsOptions struct {
@@ -312,6 +311,9 @@ type ExistsOptions struct {
 	Namespace string
 }
 
+// ExistsOption specifies Exists call options
+type ExistsOption func(*ExistsOptions)
+
 // NewExistsOptions helper for Exists method
 func NewExistsOptions(opts ...ExistsOption) ExistsOptions {
 	options := ExistsOptions{
@@ -322,3 +324,26 @@ func NewExistsOptions(opts ...ExistsOption) ExistsOptions {
 	}
 	return options
 }
+
+// ExistsContext pass context.Context to exist options
+func ExistsContext(ctx context.Context) ExistsOption {
+	return func(o *ExistsOptions) {
+		o.Context = ctx
+	}
+}
+
+// ExistsNamespace pass namespace to exist options
+func ExistsNamespace(ns string) ExistsOption {
+	return func(o *ExistsOptions) {
+		o.Namespace = ns
+	}
+}
+
+/*
+// WrapStore adds a store Wrapper to a list of options passed into the store
+func WrapStore(w Wrapper) Option {
+	return func(o *Options) {
+		o.Wrappers = append(o.Wrappers, w)
+	}
+}
+*/

store/wrapper.go

@@ -0,0 +1,82 @@
+package store
+
+import (
+	"context"
+)
+
+// LogfFunc function used for Logf method
+// type LogfFunc func(ctx context.Context, level Level, msg string, args ...interface{})
+// type Wrapper interface {
+//   Logf logs message with needed level
+//   Logf(LogfFunc) LogfFunc
+// }
+
+// NamespaceStore wrap store with namespace
+type NamespaceStore struct {
+	s  Store
+	ns string
+}
+
+var _ Store = &NamespaceStore{}
+
+func NewNamespaceStore(s Store, ns string) Store {
+	return &NamespaceStore{s: s, ns: ns}
+}
+
+func (w *NamespaceStore) Init(opts ...Option) error {
+	return w.s.Init(opts...)
+}
+
+func (w *NamespaceStore) Connect(ctx context.Context) error {
+	return w.s.Connect(ctx)
+}
+
+func (w *NamespaceStore) Disconnect(ctx context.Context) error {
+	return w.s.Disconnect(ctx)
+}
+
+func (w *NamespaceStore) Read(ctx context.Context, key string, val interface{}, opts ...ReadOption) error {
+	return w.s.Read(ctx, key, val, append(opts, ReadNamespace(w.ns))...)
+}
+
+func (w *NamespaceStore) Write(ctx context.Context, key string, val interface{}, opts ...WriteOption) error {
+	return w.s.Write(ctx, key, val, append(opts, WriteNamespace(w.ns))...)
+}
+
+func (w *NamespaceStore) Delete(ctx context.Context, key string, opts ...DeleteOption) error {
+	return w.s.Delete(ctx, key, append(opts, DeleteNamespace(w.ns))...)
+}
+
+func (w *NamespaceStore) Exists(ctx context.Context, key string, opts ...ExistsOption) error {
+	return w.s.Exists(ctx, key, append(opts, ExistsNamespace(w.ns))...)
+}
+
+func (w *NamespaceStore) List(ctx context.Context, opts ...ListOption) ([]string, error) {
+	return w.s.List(ctx, append(opts, ListNamespace(w.ns))...)
+}
+
+func (w *NamespaceStore) Options() Options {
+	return w.s.Options()
+}
+
+func (w *NamespaceStore) Name() string {
+	return w.s.Name()
+}
+
+func (w *NamespaceStore) String() string {
+	return w.s.String()
+}
+
+// type NamespaceWrapper struct{}
+
+// func NewNamespaceWrapper() Wrapper {
+//	return &NamespaceWrapper{}
+// }
+
+/*
+func (w *OmitWrapper) Logf(fn LogfFunc) LogfFunc {
+	return func(ctx context.Context, level Level, msg string, args ...interface{}) {
+		fn(ctx, level, msg, getArgs(args)...)
+	}
+}
+*/

sync/memory.go

@@ -51,7 +51,7 @@ func (m *memorySync) Leader(id string, opts ...LeaderOption) (Leader, error) {
 		id:   id,
 		resign: func(id string) error {
 			once.Do(func() {
-				m.Unlock(id)
+				_ = m.Unlock(id)
 			})
 			return nil
 		},

util/auth/auth.go

@@ -4,9 +4,9 @@ import (
 	"context"
 	"time"
 
-	"github.com/google/uuid"
 	"github.com/unistack-org/micro/v3/auth"
 	"github.com/unistack-org/micro/v3/logger"
+	"github.com/unistack-org/micro/v3/util/id"
 )
 
 // Verify the auth credentials and refresh the auth token periodically
@@ -22,7 +22,11 @@ func Verify(a auth.Auth) error {
 			auth.WithScopes("service"),
 		}
 
-		acc, err := a.Generate(uuid.New().String(), opts...)
+		id, err := id.New()
+		if err != nil {
+			return err
+		}
+		acc, err := a.Generate(id, opts...)
 		if err != nil {
 			return err
 		}
@@ -44,7 +48,7 @@ func Verify(a auth.Auth) error {
 	}
 
 	// set the credentials and token in auth options
-	a.Init(
+	_ = a.Init(
 		auth.ClientToken(token),
 		auth.Credentials(accID, accSecret),
 	)
@@ -75,7 +79,7 @@ func Verify(a auth.Auth) error {
 			}
 
 			// set the token
-			a.Init(auth.ClientToken(tok))
+			_ = a.Init(auth.ClientToken(tok))
 		}
 	}()
 

util/http/http_test.go

@@ -3,6 +3,7 @@
 package http
 
 import (
+	"io"
 	"net"
 	"net/http"
 	"testing"
@@ -80,5 +81,4 @@ func TestRoundTripper(t *testing.T) {
 	if string(b) != "hello world" {
 		t.Fatal("response is", string(b))
 	}
-
 }

util/http/trie.go

@@ -0,0 +1,239 @@
+package http
+
+import (
+	"regexp"
+	"strings"
+	"sync"
+)
+
+// TrieOptions contains search options
+type TrieOptions struct {
+	IgnoreCase bool
+}
+
+// TrieOption func signature
+type TrieOption func(*TrieOptions)
+
+// IgnoreCase says that search must be case insensitive
+func IgnoreCase(b bool) TrieOption {
+	return func(o *TrieOptions) {
+		o.IgnoreCase = b
+	}
+}
+
+// Tree is a trie tree.
+type Trie struct {
+	node   *node
+	rcache map[string]*regexp.Regexp
+	rmu    sync.RWMutex
+}
+
+// node is a node of tree
+type node struct {
+	actions  map[string]interface{} // key is method, val is handler interface
+	children map[string]*node       // key is label of next nodes
+	label    string
+}
+
+const (
+	pathRoot          string = "/"
+	pathDelimiter     string = "/"
+	paramDelimiter    string = ":"
+	leftPtnDelimiter  string = "{"
+	rightPtnDelimiter string = "}"
+	ptnWildcard       string = "(.+)"
+)
+
+// NewTree creates a new trie tree.
+func NewTrie() *Trie {
+	return &Trie{
+		node: &node{
+			label:    pathRoot,
+			actions:  make(map[string]interface{}),
+			children: make(map[string]*node),
+		},
+		rcache: make(map[string]*regexp.Regexp),
+	}
+}
+
+// Insert inserts a route definition to tree.
+func (t *Trie) Insert(methods []string, path string, handler interface{}) {
+	curNode := t.node
+	if path == pathRoot {
+		curNode.label = path
+		for _, method := range methods {
+			curNode.actions[method] = handler
+		}
+		return
+	}
+	ep := splitPath(path)
+	for i, p := range ep {
+		nextNode, ok := curNode.children[p]
+		if ok {
+			curNode = nextNode
+		}
+		// Create a new node.
+		if !ok {
+			curNode.children[p] = &node{
+				label:    p,
+				actions:  make(map[string]interface{}),
+				children: make(map[string]*node),
+			}
+			curNode = curNode.children[p]
+		}
+		// last loop.
+		// If there is already registered data, overwrite it.
+		if i == len(ep)-1 {
+			curNode.label = p
+			for _, method := range methods {
+				curNode.actions[method] = handler
+			}
+			break
+		}
+	}
+}
+
+// Search searches a path from a tree.
+func (t *Trie) Search(method string, path string, opts ...TrieOption) (interface{}, map[string]string, bool) {
+	params := make(map[string]string)
+
+	options := TrieOptions{}
+	for _, o := range opts {
+		o(&options)
+	}
+
+	curNode := t.node
+
+nodeLoop:
+	for _, p := range splitPath(path) {
+		nextNode, ok := curNode.children[p]
+		if ok {
+			curNode = nextNode
+			continue nodeLoop
+		}
+		if options.IgnoreCase {
+			// additional loop for case insensitive matching
+			for k, v := range curNode.children {
+				if literalEqual(k, p, true) {
+					curNode = v
+					continue nodeLoop
+				}
+			}
+		}
+		if len(curNode.children) == 0 {
+			if !literalEqual(curNode.label, p, options.IgnoreCase) {
+				// no matching path was found
+				return nil, nil, false
+			}
+			break
+		}
+		isParamMatch := false
+		for c := range curNode.children {
+			if string([]rune(c)[0]) == leftPtnDelimiter {
+				ptn := getPattern(c)
+				t.rmu.RLock()
+				reg, ok := t.rcache[ptn]
+				t.rmu.RUnlock()
+				if !ok {
+					var err error
+					reg, err = regexp.Compile(ptn)
+					if err != nil {
+						return nil, nil, false
+					}
+					t.rmu.Lock()
+					t.rcache[ptn] = reg
+					t.rmu.Unlock()
+				}
+				if reg.Match([]byte(p)) {
+					pn := getParamName(c)
+					params[pn] = p
+					curNode = curNode.children[c]
+					isParamMatch = true
+					break
+				}
+				// no matching param was found.
+				return nil, nil, false
+			}
+		}
+		if !isParamMatch {
+			return nil, nil, false
+		}
+	}
+	if path == pathRoot {
+		if len(curNode.actions) == 0 {
+			return nil, nil, false
+		}
+	}
+
+	handler, ok := curNode.actions[method]
+	if !ok || handler == nil {
+		return nil, nil, false
+	}
+	return handler, params, true
+}
+
+// getPattern gets a pattern from a label
+// {id:[^\d+$]} -> ^\d+$
+// {id}         -> (.+)
+func getPattern(label string) string {
+	leftI := strings.Index(label, leftPtnDelimiter)
+	rightI := strings.Index(label, paramDelimiter)
+	// if label doesn't have any pattern, return wild card pattern as default.
+	if leftI == -1 || rightI == -1 {
+		return ptnWildcard
+	}
+	return label[rightI+1 : len(label)-1]
+}
+
+// getParamName gets a parameter from a label
+// {id:[^\d+$]} -> id
+// {id}         -> id
+func getParamName(label string) string {
+	leftI := strings.Index(label, leftPtnDelimiter)
+	rightI := func(l string) int {
+		r := []rune(l)
+
+		var n int
+
+	loop:
+		for i := 0; i < len(r); i++ {
+			n = i
+			switch string(r[i]) {
+			case paramDelimiter:
+				n = i
+				break loop
+			case rightPtnDelimiter:
+				n = i
+				break loop
+			}
+
+			if i == len(r)-1 {
+				n = i + 1
+				break loop
+			}
+		}
+
+		return n
+	}(label)
+
+	return label[leftI+1 : rightI]
+}
+
+// splitPath removes an empty value in slice.
+func splitPath(path string) []string {
+	s := strings.Split(path, pathDelimiter)
+	var r []string
+	for _, str := range s {
+		if str != "" {
+			r = append(r, str)
+		}
+	}
+	return r
+}
+
+func literalEqual(component, literal string, ignoreCase bool) bool {
+	if ignoreCase {
+		return strings.EqualFold(component, literal)
+	}
+	return component == literal
+}

util/http/trie_test.go

@@ -0,0 +1,95 @@
+package http
+
+import (
+	"net/http"
+	"testing"
+)
+
+func TestTrieIgnoreCase(t *testing.T) {
+	type handler struct {
+		name string
+	}
+	tr := NewTrie()
+	tr.Insert([]string{http.MethodPut}, "/v1/create/{id}", &handler{name: "test"})
+
+	_, _, ok := tr.Search(http.MethodPut, "/v1/CREATE/12", IgnoreCase(true))
+	if !ok {
+		t.Fatalf("unexpected error")
+	}
+}
+
+func TestTrieContentType(t *testing.T) {
+	type handler struct {
+		name string
+	}
+	tr := NewTrie()
+	tr.Insert([]string{"application/json"}, "/v1/create/{id}", &handler{name: "test"})
+
+	h, _, ok := tr.Search("application/json", "/v1/create/12")
+	if !ok {
+		t.Fatalf("must be found error")
+	}
+	if h.(*handler).name != "test" {
+		t.Fatalf("invalid handler %v", h)
+	}
+	_, _, ok = tr.Search("text/xml", "/v1/create/12")
+	if ok {
+		t.Fatalf("must be not found error")
+	}
+}
+
+func TestTrieNoMatchMethod(t *testing.T) {
+	tr := NewTrie()
+	tr.Insert([]string{http.MethodPut}, "/v1/create/{id}", nil)
+
+	_, _, ok := tr.Search(http.MethodPost, "/v1/create")
+	if ok {
+		t.Fatalf("must be not found error")
+	}
+}
+
+func TestTrieMatchRegexp(t *testing.T) {
+	type handler struct{}
+	tr := NewTrie()
+	tr.Insert([]string{http.MethodPut}, "/v1/create/{category}/{id:[0-9]+}", &handler{})
+
+	_, params, ok := tr.Search(http.MethodPut, "/v1/create/test_cat/12345")
+	switch {
+	case !ok:
+		t.Fatalf("route not found")
+	case len(params) != 2:
+		t.Fatalf("param matching error %v", params)
+	case params["category"] != "test_cat":
+		t.Fatalf("param matching error %v", params)
+	}
+}
+
+func TestTrieMatchRegexpFail(t *testing.T) {
+	type handler struct{}
+	tr := NewTrie()
+	tr.Insert([]string{http.MethodPut}, "/v1/create/{id:[a-z]+}", &handler{})
+
+	_, _, ok := tr.Search(http.MethodPut, "/v1/create/12345")
+	if ok {
+		t.Fatalf("route must not be not found")
+	}
+}
+
+func TestTrieMatchLongest(t *testing.T) {
+	type handler struct {
+		name string
+	}
+	tr := NewTrie()
+	tr.Insert([]string{http.MethodPut}, "/v1/create", &handler{name: "first"})
+	tr.Insert([]string{http.MethodPut}, "/v1/create/{id:[0-9]+}", &handler{name: "second"})
+	if h, _, ok := tr.Search(http.MethodPut, "/v1/create/12345"); !ok {
+		t.Fatalf("route must be found")
+	} else if h.(*handler).name != "second" {
+		t.Fatalf("invalid handler found: %s != %s", h.(*handler).name, "second")
+	}
+	if h, _, ok := tr.Search(http.MethodPut, "/v1/create"); !ok {
+		t.Fatalf("route must be found")
+	} else if h.(*handler).name != "first" {
+		t.Fatalf("invalid handler found: %s != %s", h.(*handler).name, "first")
+	}
+}

util/id/LICENSE

@@ -0,0 +1,22 @@
+The MIT License (MIT)
+
+Copyright (c) 2018-2021 Matous Dzivjak <matousdzivjak@gmail.com>
+Copyright (c) 2021 Unistack LLC <v.tolstov@unistack.org>
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.

util/id/id.go

@@ -0,0 +1,112 @@
+package id
+
+import (
+	"context"
+	"crypto/rand"
+	"errors"
+	"math"
+
+	"github.com/unistack-org/micro/v3/logger"
+)
+
+// DefaultAlphabet is the alphabet used for ID characters by default
+var DefaultAlphabet = []rune("6789BCDFGHJKLMNPQRTWbcdfghjkmnpqrtwz")
+
+// DefaultSize is the size used for ID by default
+// To get uuid like collision specify 21
+var DefaultSize = 16
+
+// getMask generates bit mask used to obtain bits from the random bytes that are used to get index of random character
+// from the alphabet. Example: if the alphabet has 6 = (110)_2 characters it is sufficient to use mask 7 = (111)_2
+func getMask(alphabetSize int) int {
+	for i := 1; i <= 8; i++ {
+		mask := (2 << uint(i)) - 1
+		if mask >= alphabetSize-1 {
+			return mask
+		}
+	}
+	return 0
+}
+
+// New returns new id or error
+func New(opts ...Option) (string, error) {
+	options := NewOptions(opts...)
+
+	if len(options.Alphabet) == 0 || len(options.Alphabet) > 255 {
+		return "", errors.New("alphabet must not be empty and contain no more than 255 chars")
+	}
+	if options.Size <= 0 {
+		return "", errors.New("size must be positive integer")
+	}
+
+	chars := options.Alphabet
+
+	mask := getMask(len(chars))
+	// estimate how many random bytes we will need for the ID, we might actually need more but this is tradeoff
+	// between average case and worst case
+	ceilArg := 1.6 * float64(mask*options.Size) / float64(len(options.Alphabet))
+	step := int(math.Ceil(ceilArg))
+
+	id := make([]rune, options.Size)
+	bytes := make([]byte, step)
+	for j := 0; ; {
+		_, err := rand.Read(bytes)
+		if err != nil {
+			return "", err
+		}
+		for i := 0; i < step; i++ {
+			currByte := bytes[i] & byte(mask)
+			if currByte < byte(len(chars)) {
+				id[j] = chars[currByte]
+				j++
+				if j == options.Size {
+					return string(id[:options.Size]), nil
+				}
+			}
+		}
+	}
+}
+
+// Must is the same as New but fatals on error
+func Must(opts ...Option) string {
+	id, err := New(opts...)
+	if err != nil {
+		logger.Fatal(context.TODO(), err)
+	}
+	return id
+}
+
+// Options contains id deneration options
+type Options struct {
+	Alphabet []rune
+	Size     int
+}
+
+// Option func signature
+type Option func(*Options)
+
+// Alphabet specifies alphabet to use
+func Alphabet(alphabet string) Option {
+	return func(o *Options) {
+		o.Alphabet = []rune(alphabet)
+	}
+}
+
+// Size specifies id size
+func Size(size int) Option {
+	return func(o *Options) {
+		o.Size = size
+	}
+}
+
+// NewOptions returns new Options struct filled by opts
+func NewOptions(opts ...Option) Options {
+	options := Options{
+		Alphabet: DefaultAlphabet,
+		Size:     DefaultSize,
+	}
+	for _, o := range opts {
+		o(&options)
+	}
+	return options
+}

util/jitter/random.go

@@ -7,8 +7,8 @@ import (
 	"github.com/unistack-org/micro/v3/util/rand"
 )
 
-// Do returns a random time to jitter with max cap specified
-func Do(d time.Duration) time.Duration {
+// Random returns a random time to jitter with max cap specified
+func Random(d time.Duration) time.Duration {
 	var rng rand.Rand
 	v := rng.Float64() * float64(d.Nanoseconds())
 	return time.Duration(v)

util/jitter/ticker.go

@@ -0,0 +1,65 @@
+package jitter
+
+import (
+	"time"
+
+	"github.com/unistack-org/micro/v3/util/rand"
+)
+
+// Ticker is similar to time.Ticker but ticks at random intervals between
+// the min and max duration values (stored internally as int64 nanosecond
+// counts).
+type Ticker struct {
+	C    chan time.Time
+	done chan chan struct{}
+	min  int64
+	max  int64
+	rng  rand.Rand
+}
+
+// NewTicker returns a pointer to an initialized instance of the Ticker.
+// Min and max are durations of the shortest and longest allowed
+// ticks. Ticker will run in a goroutine until explicitly stopped.
+func NewTicker(min, max time.Duration) *Ticker {
+	ticker := &Ticker{
+		C:    make(chan time.Time),
+		done: make(chan chan struct{}),
+		min:  min.Nanoseconds(),
+		max:  max.Nanoseconds(),
+	}
+	go ticker.run()
+	return ticker
+}
+
+// Stop terminates the ticker goroutine and closes the C channel.
+func (ticker *Ticker) Stop() {
+	c := make(chan struct{})
+	ticker.done <- c
+	<-c
+}
+
+func (ticker *Ticker) run() {
+	defer close(ticker.C)
+	t := time.NewTimer(ticker.nextInterval())
+	for {
+		// either a stop signal or a timeout
+		select {
+		case c := <-ticker.done:
+			t.Stop()
+			close(c)
+			return
+		case <-t.C:
+			select {
+			case ticker.C <- time.Now():
+				t.Stop()
+				t = time.NewTimer(ticker.nextInterval())
+			default:
+				// there could be noone receiving...
+			}
+		}
+	}
+}
+
+func (ticker *Ticker) nextInterval() time.Duration {
+	return time.Duration(ticker.rng.Int63n(ticker.max-ticker.min)+ticker.min) * time.Nanosecond
+}

util/pool/default.go

@@ -5,8 +5,8 @@ import (
 	"sync"
 	"time"
 
-	"github.com/google/uuid"
 	"github.com/unistack-org/micro/v3/network/transport"
+	"github.com/unistack-org/micro/v3/util/id"
 )
 
 type pool struct {
@@ -49,7 +49,7 @@ func (p *poolConn) Close() error {
 	return nil
 }
 
-func (p *poolConn) Id() string {
+func (p *poolConn) ID() string {
 	return p.id
 }
 
@@ -87,9 +87,13 @@ func (p *pool) Get(ctx context.Context, addr string, opts ...transport.DialOptio
 	if err != nil {
 		return nil, err
 	}
+	id, err := id.New()
+	if err != nil {
+		return nil, err
+	}
 	return &poolConn{
 		Client:  c,
-		id:      uuid.New().String(),
+		id:      id,
 		created: time.Now(),
 	}, nil
 }

util/pool/pool.go

@@ -21,7 +21,7 @@ type Pool interface {
 // Conn conn pool interface
 type Conn interface {
 	// unique id of connection
-	Id() string
+	ID() string
 	// time it was created
 	Created() time.Time
 	// embedded connection

util/qson/qson.go

@@ -16,7 +16,7 @@ import (
 var (
 	// ErrInvalidParam is returned when invalid data is provided to the ToJSON or Unmarshal function.
 	// Specifically, this will be returned when there is no equals sign present in the URL query parameter.
-	ErrInvalidParam error = errors.New("qson: invalid url query param provided")
+	ErrInvalidParam = errors.New("qson: invalid url query param provided")
 
 	bracketSplitter *regexp.Regexp
 )

util/rand/rand.go

@@ -1,17 +1,17 @@
 package rand
 
 import (
-	"crypto/rand"
+	crand "crypto/rand"
 	"encoding/binary"
 )
 
-// Rand is a wrapper around crypto/rand that adds some convenience functions known from math/rand.
+// Rand is a wrapper around crypto/rand that adds some convenience functions known from math/rand
 type Rand struct {
 	buf [8]byte
 }
 
 func (r *Rand) Int31() int32 {
-	_, _ = rand.Read(r.buf[:4])
+	_, _ = crand.Read(r.buf[:4])
 	return int32(binary.BigEndian.Uint32(r.buf[:4]) & ^uint32(1<<31))
 }
 
@@ -54,11 +54,11 @@ func (r *Rand) Intn(n int) int {
 }
 
 func (r *Rand) Int63() int64 {
-	_, _ = rand.Read(r.buf[:])
+	_, _ = crand.Read(r.buf[:])
 	return int64(binary.BigEndian.Uint64(r.buf[:]) & ^uint64(1<<63))
 }
 
-// copied from the standard library math/rand implementation of Int63n
+// Int31n copied from the standard library math/rand implementation of Int31n
 func (r *Rand) Int31n(n int32) int32 {
 	if n&(n-1) == 0 { // n is power of two, can mask
 		return r.Int31() & (n - 1)
@@ -71,6 +71,7 @@ func (r *Rand) Int31n(n int32) int32 {
 	return v % n
 }
 
+// Int63n copied from the standard library math/rand implementation of Int63n
 func (r *Rand) Int63n(n int64) int64 {
 	if n&(n-1) == 0 { // n is power of two, can mask
 		return r.Int63() & (n - 1)
@@ -82,3 +83,26 @@ func (r *Rand) Int63n(n int64) int64 {
 	}
 	return v % n
 }
+
+// Shuffle copied from the standard library math/rand implementation of Shuffle
+func (r *Rand) Shuffle(n int, swap func(i, j int)) {
+	if n < 0 {
+		panic("invalid argument to Shuffle")
+	}
+
+	// Fisher-Yates shuffle: https://en.wikipedia.org/wiki/Fisher%E2%80%93Yates_shuffle
+	// Shuffle really ought not be called with n that doesn't fit in 32 bits.
+	// Not only will it take a very long time, but with 2³¹! possible permutations,
+	// there's no way that any PRNG can have a big enough internal state to
+	// generate even a minuscule percentage of the possible permutations.
+	// Nevertheless, the right API signature accepts an int n, so handle it as best we can.
+	i := n - 1
+	for ; i > 1<<31-1-1; i-- {
+		j := int(r.Int63n(int64(i + 1)))
+		swap(i, j)
+	}
+	for ; i > 0; i-- {
+		j := int(r.Int31n(int32(i + 1)))
+		swap(i, j)
+	}
+}

util/reflect/path.go

@@ -82,9 +82,9 @@ func getValueByName(v reflect.Value, key string) (reflect.Value, error) {
 	case reflect.Struct:
 		value = v.FieldByName(key)
 	case reflect.Map:
-		kValue := reflect.Indirect(reflect.New(v.Type().Key()))
-		kValue.SetString(key)
-		value = v.MapIndex(kValue)
+		kvalue := reflect.Indirect(reflect.New(v.Type().Key()))
+		kvalue.SetString(key)
+		value = v.MapIndex(kvalue)
 	}
 
 	if !value.IsValid() {

util/reflect/struct.go

@@ -7,21 +7,24 @@ import (
 	"reflect"
 	"regexp"
 	"strings"
-	"time"
 )
 
 // ErrInvalidParam specifies invalid url query params
 var ErrInvalidParam = errors.New("invalid url query param provided")
 
+// var timeKind = reflect.ValueOf(time.Time{}).Kind()
+
+// bracketSplitter
 var bracketSplitter = regexp.MustCompile(`\[|\]`)
 
-var timeKind = reflect.TypeOf(time.Time{}).Kind()
-
+// StructField contains struct field path its value and field
 type StructField struct {
-	Field reflect.StructField
+	Path  string
 	Value reflect.Value
+	Field reflect.StructField
 }
 
+// StructFieldByTag get struct field by tag key and its value
 func StructFieldByTag(src interface{}, tkey string, tval string) (interface{}, error) {
 	sv := reflect.ValueOf(src)
 	if sv.Kind() == reflect.Ptr {
@@ -35,7 +38,7 @@ func StructFieldByTag(src interface{}, tkey string, tval string) (interface{}, e
 	for idx := 0; idx < typ.NumField(); idx++ {
 		fld := typ.Field(idx)
 		val := sv.Field(idx)
-		if !val.CanSet() || len(fld.PkgPath) != 0 {
+		if len(fld.PkgPath) != 0 {
 			continue
 		}
 
@@ -66,6 +69,19 @@ func StructFieldByTag(src interface{}, tkey string, tval string) (interface{}, e
 	return nil, ErrNotFound
 }
 
+// StructFieldByPath get struct field by its path
+func StructFieldByPath(src interface{}, path string) (interface{}, error) {
+	var err error
+	for _, p := range strings.Split(path, ".") {
+		src, err = StructFieldByName(src, p)
+		if err != nil {
+			return nil, err
+		}
+	}
+	return src, err
+}
+
+// StructFieldByName get struct field by its name
 func StructFieldByName(src interface{}, tkey string) (interface{}, error) {
 	sv := reflect.ValueOf(src)
 	if sv.Kind() == reflect.Ptr {
@@ -79,7 +95,7 @@ func StructFieldByName(src interface{}, tkey string) (interface{}, error) {
 	for idx := 0; idx < typ.NumField(); idx++ {
 		fld := typ.Field(idx)
 		val := sv.Field(idx)
-		if !val.CanSet() || len(fld.PkgPath) != 0 {
+		if len(fld.PkgPath) != 0 {
 			continue
 		}
 		if fld.Name == tkey {
@@ -105,6 +121,19 @@ func StructFieldByName(src interface{}, tkey string) (interface{}, error) {
 	return nil, ErrNotFound
 }
 
+// StructFieldsMap returns struct map[string]interface{} or error
+func StructFieldsMap(src interface{}) (map[string]interface{}, error) {
+	fields, err := StructFields(src)
+	if err != nil {
+		return nil, err
+	}
+	mp := make(map[string]interface{}, len(fields))
+	for _, field := range fields {
+		mp[field.Path] = field.Value.Interface()
+	}
+	return mp, nil
+}
+
 // StructFields returns slice of struct fields
 func StructFields(src interface{}) ([]StructField, error) {
 	var fields []StructField
@@ -116,25 +145,29 @@ func StructFields(src interface{}) ([]StructField, error) {
 	if sv.Kind() != reflect.Struct {
 		return nil, ErrInvalidStruct
 	}
-
 	typ := sv.Type()
 	for idx := 0; idx < typ.NumField(); idx++ {
 		fld := typ.Field(idx)
 		val := sv.Field(idx)
-		if !val.CanSet() || len(fld.PkgPath) != 0 {
+		if !val.IsValid() || len(fld.PkgPath) != 0 {
 			continue
 		}
+
 		switch val.Kind() {
-		case timeKind:
-			fields = append(fields, StructField{Field: fld, Value: val})
+		// case timeKind:
+		// fmt.Printf("GGG\n")
+		// fields = append(fields, StructField{Field: fld, Value: val, Path: fld.Name})
 		case reflect.Struct:
 			infields, err := StructFields(val.Interface())
 			if err != nil {
 				return nil, err
 			}
-			fields = append(fields, infields...)
+			for _, infield := range infields {
+				infield.Path = fmt.Sprintf("%s.%s", fld.Name, infield.Path)
+				fields = append(fields, infield)
+			}
 		default:
-			fields = append(fields, StructField{Field: fld, Value: val})
+			fields = append(fields, StructField{Field: fld, Value: val, Path: fld.Name})
 		}
 	}
 
@@ -179,6 +212,7 @@ func CopyFrom(a, b interface{}) {
 	}
 }
 
+// StructURLValues get struct fields via url.Values
 func StructURLValues(src interface{}, pref string, tags []string) (url.Values, error) {
 	data := url.Values{}
 
@@ -194,7 +228,7 @@ func StructURLValues(src interface{}, pref string, tags []string) (url.Values, e
 	for idx := 0; idx < typ.NumField(); idx++ {
 		fld := typ.Field(idx)
 		val := sv.Field(idx)
-		if !val.CanSet() || len(fld.PkgPath) != 0 || !val.IsValid() {
+		if len(fld.PkgPath) != 0 || !val.IsValid() {
 			continue
 		}
 

util/reflect/struct_test.go

@@ -1,10 +1,82 @@
-package reflect
+package reflect_test
 
 import (
 	"net/url"
+	"reflect"
 	"testing"
+
+	rutil "github.com/unistack-org/micro/v3/util/reflect"
 )
 
+func TestStructFieldsMap(t *testing.T) {
+	type NestedStr struct {
+		BBB string
+		CCC int
+	}
+	type Str struct {
+		Name   []string `json:"name" codec:"flatten"`
+		XXX    string   `json:"xxx"`
+		Nested NestedStr
+	}
+
+	val := &Str{Name: []string{"first", "second"}, XXX: "ttt", Nested: NestedStr{BBB: "ddd", CCC: 9}}
+	fields, err := rutil.StructFieldsMap(val)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if v, ok := fields["Nested.BBB"]; !ok || v != "ddd" {
+		t.Fatalf("invalid field from %v", fields)
+	}
+}
+
+func TestStructFields(t *testing.T) {
+	type NestedStr struct {
+		BBB string
+		CCC int
+	}
+	type Str struct {
+		Name   []string `json:"name" codec:"flatten"`
+		XXX    string   `json:"xxx"`
+		Nested NestedStr
+	}
+
+	val := &Str{Name: []string{"first", "second"}, XXX: "ttt", Nested: NestedStr{BBB: "ddd", CCC: 9}}
+	fields, err := rutil.StructFields(val)
+	if err != nil {
+		t.Fatal(err)
+	}
+	var ok bool
+	for _, field := range fields {
+		if field.Path == "Nested.CCC" {
+			ok = true
+		}
+	}
+	if !ok {
+		t.Fatalf("struct fields returns invalid path: %v", fields)
+	}
+}
+
+func TestStructByPath(t *testing.T) {
+	type NestedStr struct {
+		BBB string
+		CCC int
+	}
+	type Str struct {
+		Name   []string `json:"name" codec:"flatten"`
+		XXX    string   `json:"xxx"`
+		Nested NestedStr
+	}
+
+	val := &Str{Name: []string{"first", "second"}, XXX: "ttt", Nested: NestedStr{BBB: "ddd", CCC: 9}}
+	field, err := rutil.StructFieldByPath(val, "Nested.CCC")
+	if err != nil {
+		t.Fatal(err)
+	}
+	if reflect.Indirect(reflect.ValueOf(field)).Int() != 9 {
+		t.Fatalf("invalid elem returned: %v", field)
+	}
+}
+
 func TestStructByTag(t *testing.T) {
 	type Str struct {
 		Name []string `json:"name" codec:"flatten"`
@@ -12,7 +84,7 @@ func TestStructByTag(t *testing.T) {
 
 	val := &Str{Name: []string{"first", "second"}}
 
-	iface, err := StructFieldByTag(val, "codec", "flatten")
+	iface, err := rutil.StructFieldByTag(val, "codec", "flatten")
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -31,7 +103,7 @@ func TestStructByName(t *testing.T) {
 
 	val := &Str{Name: []string{"first", "second"}}
 
-	iface, err := StructFieldByName(val, "Name")
+	iface, err := rutil.StructFieldByName(val, "Name")
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -51,7 +123,7 @@ func TestStructURLValues(t *testing.T) {
 	}
 
 	val := &Str{Name: "test_name", Args: []int{1, 2, 3}, Str: &Str{Name: "nested_name"}}
-	data, err := StructURLValues(val, "", []string{"json"})
+	data, err := rutil.StructURLValues(val, "", []string{"json"})
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -67,7 +139,7 @@ func TestURLSliceVars(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	mp, err := URLMap(u.RawQuery)
+	mp, err := rutil.URLMap(u.RawQuery)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -93,7 +165,7 @@ func TestURLVars(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	mp, err := URLMap(u.RawQuery)
+	mp, err := rutil.URLMap(u.RawQuery)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -113,14 +185,14 @@ func TestIsZero(t *testing.T) {
 	}
 	testStr1.Nested.NestedName = "nested_name"
 
-	if ok := IsZero(testStr1); ok {
+	if ok := rutil.IsZero(testStr1); ok {
 		t.Fatalf("zero ret on non zero struct: %#+v", testStr1)
 	}
 
 	testStr1.Name = ""
 	testStr1.Value = ""
 	testStr1.Nested.NestedName = ""
-	if ok := IsZero(testStr1); !ok {
+	if ok := rutil.IsZero(testStr1); !ok {
 		t.Fatalf("non zero ret on zero struct: %#+v", testStr1)
 	}
 
@@ -135,12 +207,12 @@ func TestIsZero(t *testing.T) {
 		Name:   "test_name",
 		Nested: &testStr3{Nested: "nested_name"},
 	}
-	if ok := IsZero(vtest); ok {
+	if ok := rutil.IsZero(vtest); ok {
 		t.Fatalf("zero ret on non zero struct: %#+v", vtest)
 	}
 	vtest.Nested = nil
 	vtest.Name = ""
-	if ok := IsZero(vtest); !ok {
+	if ok := rutil.IsZero(vtest); !ok {
 		t.Fatalf("non zero ret on zero struct: %#+v", vtest)
 	}
 

util/ring/buffer.go

@@ -5,7 +5,7 @@ import (
 	"sync"
 	"time"
 
-	"github.com/google/uuid"
+	"github.com/unistack-org/micro/v3/util/id"
 )
 
 // Buffer is ring buffer
@@ -28,8 +28,8 @@ type Stream struct {
 	Entries chan *Entry
 	// Stop channel
 	Stop chan bool
-	// Id of the stream
-	Id string
+	// ID of the stream
+	ID string
 }
 
 // Put adds a new value to ring buffer
@@ -53,7 +53,7 @@ func (b *Buffer) Put(v interface{}) {
 	for _, stream := range b.streams {
 		select {
 		case <-stream.Stop:
-			delete(b.streams, stream.Id)
+			delete(b.streams, stream.ID)
 			close(stream.Entries)
 		case stream.Entries <- entry:
 		}
@@ -112,11 +112,11 @@ func (b *Buffer) Stream() (<-chan *Entry, chan bool) {
 	defer b.Unlock()
 
 	entries := make(chan *Entry, 128)
-	id := uuid.New().String()
+	id := id.Must()
 	stop := make(chan bool)
 
 	b.streams[id] = &Stream{
-		Id:      id,
+		ID:      id,
 		Entries: entries,
 		Stop:    stop,
 	}

util/router/LICENSE.txt

@@ -1,27 +0,0 @@
-Copyright (c) 2015, Gengo, Inc.
-All rights reserved.
-
-Redistribution and use in source and binary forms, with or without modification,
-are permitted provided that the following conditions are met:
-
-    * Redistributions of source code must retain the above copyright notice,
-      this list of conditions and the following disclaimer.
-
-    * Redistributions in binary form must reproduce the above copyright notice,
-      this list of conditions and the following disclaimer in the documentation
-      and/or other materials provided with the distribution.
-
-    * Neither the name of Gengo, Inc. nor the names of its
-      contributors may be used to endorse or promote products derived from this
-      software without specific prior written permission.
-
-THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
-ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
-WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
-DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
-ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
-(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
-LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
-ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
-SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

util/router/compile.go

@@ -1,110 +0,0 @@
-package router
-
-// download from https://raw.githubusercontent.com/grpc-ecosystem/grpc-gateway/master/protoc-gen-grpc-gateway/httprule/compile.go
-
-const (
-	opcodeVersion = 1
-)
-
-// Template is a compiled representation of path templates.
-type Template struct {
-	// Verb is a VERB part in the template
-	Verb string
-	// Original template (example: /v1/a_bit_of_everything)
-	Template string
-	// OpCodes is a sequence of operations
-	OpCodes []int
-	// Pool is a constant pool
-	Pool []string
-	// Fields is a list of field paths bound in this template
-	Fields []string
-	// Version is the version number of the format
-	Version int
-}
-
-// Compiler compiles utilities representation of path templates into marshallable operations.
-// They can be unmarshalled by runtime.NewPattern.
-type Compiler interface {
-	Compile() Template
-}
-
-type op struct {
-	str     string
-	code    OpCode
-	operand int
-}
-
-func (w wildcard) compile() []op {
-	return []op{
-		{code: OpPush},
-	}
-}
-
-func (w deepWildcard) compile() []op {
-	return []op{
-		{code: OpPushM},
-	}
-}
-
-func (l literal) compile() []op {
-	return []op{
-		{
-			code: OpLitPush,
-			str:  string(l),
-		},
-	}
-}
-
-func (v variable) compile() []op {
-	ops := make([]op, 0, len(v.segments))
-	for _, s := range v.segments {
-		ops = append(ops, s.compile()...)
-	}
-	ops = append(ops, op{
-		code:    OpConcatN,
-		operand: len(v.segments),
-	}, op{
-		code: OpCapture,
-		str:  v.path,
-	})
-
-	return ops
-}
-
-func (t template) Compile() Template {
-	rawOps := make([]op, 0, len(t.segments))
-	for _, s := range t.segments {
-		rawOps = append(rawOps, s.compile()...)
-	}
-
-	// ops := make([]int, 0, len(rawOps))
-	var (
-		ops    []int
-		pool   []string
-		fields []string
-	)
-	consts := make(map[string]int)
-	for _, op := range rawOps {
-		ops = append(ops, int(op.code))
-		if op.str == "" {
-			ops = append(ops, op.operand)
-		} else {
-			if _, ok := consts[op.str]; !ok {
-				consts[op.str] = len(pool)
-				pool = append(pool, op.str)
-			}
-			ops = append(ops, consts[op.str])
-		}
-		if op.code == OpCapture {
-			fields = append(fields, op.str)
-		}
-	}
-	return Template{
-		Version:  opcodeVersion,
-		OpCodes:  ops,
-		Pool:     pool,
-		Verb:     t.verb,
-		Fields:   fields,
-		Template: t.template,
-	}
-}

util/router/compile_test.go

@@ -1,122 +0,0 @@
-package router
-
-// download from https://raw.githubusercontent.com/grpc-ecosystem/grpc-gateway/master/protoc-gen-grpc-gateway/httprule/compile_test.go
-
-import (
-	"reflect"
-	"testing"
-)
-
-const (
-	operandFiller = 0
-)
-
-func TestCompile(t *testing.T) {
-	for _, spec := range []struct {
-		segs []segment
-		verb string
-
-		ops    []int
-		pool   []string
-		fields []string
-	}{
-		{},
-		{
-			segs: []segment{
-				wildcard{},
-			},
-			ops: []int{int(OpPush), operandFiller},
-		},
-		{
-			segs: []segment{
-				deepWildcard{},
-			},
-			ops: []int{int(OpPushM), operandFiller},
-		},
-		{
-			segs: []segment{
-				literal("v1"),
-			},
-			ops:  []int{int(OpLitPush), 0},
-			pool: []string{"v1"},
-		},
-		{
-			segs: []segment{
-				literal("v1"),
-			},
-			verb: "LOCK",
-			ops:  []int{int(OpLitPush), 0},
-			pool: []string{"v1"},
-		},
-		{
-			segs: []segment{
-				variable{
-					path: "name.nested",
-					segments: []segment{
-						wildcard{},
-					},
-				},
-			},
-			ops: []int{
-				int(OpPush), operandFiller,
-				int(OpConcatN), 1,
-				int(OpCapture), 0,
-			},
-			pool:   []string{"name.nested"},
-			fields: []string{"name.nested"},
-		},
-		{
-			segs: []segment{
-				literal("obj"),
-				variable{
-					path: "name.nested",
-					segments: []segment{
-						literal("a"),
-						wildcard{},
-						literal("b"),
-					},
-				},
-				variable{
-					path: "obj",
-					segments: []segment{
-						deepWildcard{},
-					},
-				},
-			},
-			ops: []int{
-				int(OpLitPush), 0,
-				int(OpLitPush), 1,
-				int(OpPush), operandFiller,
-				int(OpLitPush), 2,
-				int(OpConcatN), 3,
-				int(OpCapture), 3,
-				int(OpPushM), operandFiller,
-				int(OpConcatN), 1,
-				int(OpCapture), 0,
-			},
-			pool:   []string{"obj", "a", "b", "name.nested"},
-			fields: []string{"name.nested", "obj"},
-		},
-	} {
-		tmpl := template{
-			segments: spec.segs,
-			verb:     spec.verb,
-		}
-		compiled := tmpl.Compile()
-		if got, want := compiled.Version, opcodeVersion; got != want {
-			t.Errorf("tmpl.Compile().Version = %d; want %d; segs=%#v, verb=%q", got, want, spec.segs, spec.verb)
-		}
-		if got, want := compiled.OpCodes, spec.ops; !reflect.DeepEqual(got, want) {
-			t.Errorf("tmpl.Compile().OpCodes = %v; want %v; segs=%#v, verb=%q", got, want, spec.segs, spec.verb)
-		}
-		if got, want := compiled.Pool, spec.pool; !reflect.DeepEqual(got, want) {
-			t.Errorf("tmpl.Compile().Pool = %q; want %q; segs=%#v, verb=%q", got, want, spec.segs, spec.verb)
-		}
-		if got, want := compiled.Verb, spec.verb; got != want {
-			t.Errorf("tmpl.Compile().Verb = %q; want %q; segs=%#v, verb=%q", got, want, spec.segs, spec.verb)
-		}
-		if got, want := compiled.Fields, spec.fields; !reflect.DeepEqual(got, want) {
-			t.Errorf("tmpl.Compile().Fields = %q; want %q; segs=%#v, verb=%q", got, want, spec.segs, spec.verb)
-		}
-	}
-}

util/router/parse.go

@@ -1,363 +0,0 @@
-package router
-
-// download from https://raw.githubusercontent.com/grpc-ecosystem/grpc-gateway/master/protoc-gen-grpc-gateway/httprule/parse.go
-
-import (
-	"context"
-	"fmt"
-	"strings"
-
-	"github.com/unistack-org/micro/v3/logger"
-)
-
-// InvalidTemplateError indicates that the path template is not valid.
-type InvalidTemplateError struct {
-	tmpl string
-	msg  string
-}
-
-func (e InvalidTemplateError) Error() string {
-	return fmt.Sprintf("%s: %s", e.msg, e.tmpl)
-}
-
-// Parse parses the string representation of path template
-func Parse(tmpl string) (Compiler, error) {
-	if !strings.HasPrefix(tmpl, "/") {
-		return template{}, InvalidTemplateError{tmpl: tmpl, msg: "no leading /"}
-	}
-	tokens, verb := tokenize(tmpl[1:])
-
-	p := parser{tokens: tokens}
-	segs, err := p.topLevelSegments()
-	if err != nil {
-		return template{}, InvalidTemplateError{tmpl: tmpl, msg: err.Error()}
-	}
-
-	return template{
-		segments: segs,
-		verb:     verb,
-		template: tmpl,
-	}, nil
-}
-
-func tokenize(path string) (tokens []string, verb string) {
-	if path == "" {
-		return []string{eof}, ""
-	}
-
-	const (
-		init = iota
-		field
-		nested
-	)
-	st := init
-	for path != "" {
-		var idx int
-		switch st {
-		case init:
-			idx = strings.IndexAny(path, "/{")
-		case field:
-			idx = strings.IndexAny(path, ".=}")
-		case nested:
-			idx = strings.IndexAny(path, "/}")
-		}
-		if idx < 0 {
-			tokens = append(tokens, path)
-			break
-		}
-		switch r := path[idx]; r {
-		case '/', '.':
-		case '{':
-			st = field
-		case '=':
-			st = nested
-		case '}':
-			st = init
-		}
-		if idx == 0 {
-			tokens = append(tokens, path[idx:idx+1])
-		} else {
-			tokens = append(tokens, path[:idx], path[idx:idx+1])
-		}
-		path = path[idx+1:]
-	}
-
-	l := len(tokens)
-	t := tokens[l-1]
-	if idx := strings.LastIndex(t, ":"); idx == 0 {
-		tokens, verb = tokens[:l-1], t[1:]
-	} else if idx > 0 {
-		tokens[l-1], verb = t[:idx], t[idx+1:]
-	}
-	tokens = append(tokens, eof)
-	return tokens, verb
-}
-
-// parser is a parser of the template syntax defined in github.com/googleapis/googleapis/google/api/http.proto.
-type parser struct {
-	tokens   []string
-	accepted []string
-}
-
-// topLevelSegments is the target of this parser.
-func (p *parser) topLevelSegments() ([]segment, error) {
-	if logger.V(logger.TraceLevel) {
-		logger.Debug(context.TODO(), "Parsing %q", p.tokens)
-	}
-	segs, err := p.segments()
-	if err != nil {
-		return nil, err
-	}
-	if logger.V(logger.TraceLevel) {
-		logger.Trace(context.TODO(), "accept segments: %q; %q", p.accepted, p.tokens)
-	}
-	if _, err := p.accept(typeEOF); err != nil {
-		return nil, fmt.Errorf("unexpected token %q after segments %q", p.tokens[0], strings.Join(p.accepted, ""))
-	}
-	if logger.V(logger.TraceLevel) {
-		logger.Trace(context.TODO(), "accept eof: %q; %q", p.accepted, p.tokens)
-	}
-	return segs, nil
-}
-
-func (p *parser) segments() ([]segment, error) {
-	s, err := p.segment()
-	if err != nil {
-		return nil, err
-	}
-
-	if logger.V(logger.TraceLevel) {
-		logger.Trace(context.TODO(), "accept segment: %q; %q", p.accepted, p.tokens)
-	}
-	segs := []segment{s}
-	for {
-		if _, err := p.accept("/"); err != nil {
-			return segs, nil
-		}
-		s, err := p.segment()
-		if err != nil {
-			return segs, err
-		}
-		segs = append(segs, s)
-		if logger.V(logger.TraceLevel) {
-			logger.Trace(context.TODO(), "accept segment: %q; %q", p.accepted, p.tokens)
-		}
-	}
-}
-
-func (p *parser) segment() (segment, error) {
-	if _, err := p.accept("*"); err == nil {
-		return wildcard{}, nil
-	}
-	if _, err := p.accept("**"); err == nil {
-		return deepWildcard{}, nil
-	}
-	if l, err := p.literal(); err == nil {
-		return l, nil
-	}
-
-	v, err := p.variable()
-	if err != nil {
-		return nil, fmt.Errorf("segment neither wildcards, literal or variable: %v", err)
-	}
-	return v, err
-}
-
-func (p *parser) literal() (segment, error) {
-	lit, err := p.accept(typeLiteral)
-	if err != nil {
-		return nil, err
-	}
-	return literal(lit), nil
-}
-
-func (p *parser) variable() (segment, error) {
-	if _, err := p.accept("{"); err != nil {
-		return nil, err
-	}
-
-	path, err := p.fieldPath()
-	if err != nil {
-		return nil, err
-	}
-
-	var segs []segment
-	if _, err := p.accept("="); err == nil {
-		segs, err = p.segments()
-		if err != nil {
-			return nil, fmt.Errorf("invalid segment in variable %q: %v", path, err)
-		}
-	} else {
-		segs = []segment{wildcard{}}
-	}
-
-	if _, err := p.accept("}"); err != nil {
-		return nil, fmt.Errorf("unterminated variable segment: %s", path)
-	}
-	return variable{
-		path:     path,
-		segments: segs,
-	}, nil
-}
-
-func (p *parser) fieldPath() (string, error) {
-	c, err := p.accept(typeIdent)
-	if err != nil {
-		return "", err
-	}
-	components := []string{c}
-	for {
-		if _, err = p.accept("."); err != nil {
-			return strings.Join(components, "."), nil
-		}
-		c, err := p.accept(typeIdent)
-		if err != nil {
-			return "", fmt.Errorf("invalid field path component: %v", err)
-		}
-		components = append(components, c)
-	}
-}
-
-// A termType is a type of terminal symbols.
-type termType string
-
-// These constants define some of valid values of termType.
-// They improve readability of parse functions.
-//
-// You can also use "/", "*", "**", "." or "=" as valid values.
-const (
-	typeIdent   = termType("ident")
-	typeLiteral = termType("literal")
-	typeEOF     = termType("$")
-)
-
-const (
-	// eof is the terminal symbol which always appears at the end of token sequence.
-	eof = "\u0000"
-)
-
-// accept tries to accept a token in "p".
-// This function consumes a token and returns it if it matches to the specified "term".
-// If it doesn't match, the function does not consume any tokens and return an error.
-func (p *parser) accept(term termType) (string, error) {
-	t := p.tokens[0]
-	switch term {
-	case "/", "*", "**", ".", "=", "{", "}":
-		if t != string(term) && t != "/" {
-			return "", fmt.Errorf("expected %q but got %q", term, t)
-		}
-	case typeEOF:
-		if t != eof {
-			return "", fmt.Errorf("expected EOF but got %q", t)
-		}
-	case typeIdent:
-		if err := expectIdent(t); err != nil {
-			return "", err
-		}
-	case typeLiteral:
-		if err := expectPChars(t); err != nil {
-			return "", err
-		}
-	default:
-		return "", fmt.Errorf("unknown termType %q", term)
-	}
-	p.tokens = p.tokens[1:]
-	p.accepted = append(p.accepted, t)
-	return t, nil
-}
-
-// expectPChars determines if "t" consists of only pchars defined in RFC3986.
-//
-// https://www.ietf.org/rfc/rfc3986.txt, P.49
-//   pchar         = unreserved / pct-encoded / sub-delims / ":" / "@"
-//   unreserved    = ALPHA / DIGIT / "-" / "." / "_" / "~"
-//   sub-delims    = "!" / "$" / "&" / "'" / "(" / ")"
-//                 / "*" / "+" / "," / ";" / "="
-//   pct-encoded   = "%" HEXDIG HEXDIG
-//nolint:gocyclo
-func expectPChars(t string) error {
-	const (
-		init = iota
-		pct1
-		pct2
-	)
-	st := init
-	for _, r := range t {
-		if st != init {
-			if !isHexDigit(r) {
-				return fmt.Errorf("invalid hexdigit: %c(%U)", r, r)
-			}
-			switch st {
-			case pct1:
-				st = pct2
-			case pct2:
-				st = init
-			}
-			continue
-		}
-
-		// unreserved
-		switch {
-		case 'A' <= r && r <= 'Z':
-			continue
-		case 'a' <= r && r <= 'z':
-			continue
-		case '0' <= r && r <= '9':
-			continue
-		}
-		switch r {
-		case '-', '.', '_', '~':
-			// unreserved
-		case '!', '$', '&', '\'', '(', ')', '*', '+', ',', ';', '=':
-			// sub-delims
-		case ':', '@':
-			// rest of pchar
-		case '%':
-			// pct-encoded
-			st = pct1
-		default:
-			return fmt.Errorf("invalid character in path segment: %q(%U)", r, r)
-		}
-	}
-	if st != init {
-		return fmt.Errorf("invalid percent-encoding in %q", t)
-	}
-	return nil
-}
-
-// expectIdent determines if "ident" is a valid identifier in .proto schema ([[:alpha:]_][[:alphanum:]_]*).
-func expectIdent(ident string) error {
-	if ident == "" {
-		return fmt.Errorf("empty identifier")
-	}
-	for pos, r := range ident {
-		switch {
-		case '0' <= r && r <= '9':
-			if pos == 0 {
-				return fmt.Errorf("identifier starting with digit: %s", ident)
-			}
-			continue
-		case 'A' <= r && r <= 'Z':
-			continue
-		case 'a' <= r && r <= 'z':
-			continue
-		case r == '_':
-			continue
-		default:
-			return fmt.Errorf("invalid character %q(%U) in identifier: %s", r, r, ident)
-		}
-	}
-	return nil
-}
-
-func isHexDigit(r rune) bool {
-	switch {
-	case '0' <= r && r <= '9':
-		return true
-	case 'A' <= r && r <= 'F':
-		return true
-	case 'a' <= r && r <= 'f':
-		return true
-	}
-	return false
-}

util/router/parse_test.go

@@ -1,323 +0,0 @@
-package router
-
-// download from https://raw.githubusercontent.com/grpc-ecosystem/grpc-gateway/master/protoc-gen-grpc-gateway/httprule/parse_test.go
-
-import (
-	"context"
-	"flag"
-	"fmt"
-	"reflect"
-	"testing"
-
-	"github.com/unistack-org/micro/v3/logger"
-)
-
-func TestTokenize(t *testing.T) {
-	for _, spec := range []struct {
-		src    string
-		tokens []string
-	}{
-		{
-			src:    "",
-			tokens: []string{eof},
-		},
-		{
-			src:    "v1",
-			tokens: []string{"v1", eof},
-		},
-		{
-			src:    "v1/b",
-			tokens: []string{"v1", "/", "b", eof},
-		},
-		{
-			src:    "v1/endpoint/*",
-			tokens: []string{"v1", "/", "endpoint", "/", "*", eof},
-		},
-		{
-			src:    "v1/endpoint/**",
-			tokens: []string{"v1", "/", "endpoint", "/", "**", eof},
-		},
-		{
-			src: "v1/b/{bucket_name=*}",
-			tokens: []string{
-				"v1", "/",
-				"b", "/",
-				"{", "bucket_name", "=", "*", "}",
-				eof,
-			},
-		},
-		{
-			src: "v1/b/{bucket_name=buckets/*}",
-			tokens: []string{
-				"v1", "/",
-				"b", "/",
-				"{", "bucket_name", "=", "buckets", "/", "*", "}",
-				eof,
-			},
-		},
-		{
-			src: "v1/b/{bucket_name=buckets/*}/o",
-			tokens: []string{
-				"v1", "/",
-				"b", "/",
-				"{", "bucket_name", "=", "buckets", "/", "*", "}", "/",
-				"o",
-				eof,
-			},
-		},
-		{
-			src: "v1/b/{bucket_name=buckets/*}/o/{name}",
-			tokens: []string{
-				"v1", "/",
-				"b", "/",
-				"{", "bucket_name", "=", "buckets", "/", "*", "}", "/",
-				"o", "/", "{", "name", "}",
-				eof,
-			},
-		},
-		{
-			src: "v1/a=b&c=d;e=f:g/endpoint.rdf",
-			tokens: []string{
-				"v1", "/",
-				"a=b&c=d;e=f:g", "/",
-				"endpoint.rdf",
-				eof,
-			},
-		},
-	} {
-		tokens, verb := tokenize(spec.src)
-		if got, want := tokens, spec.tokens; !reflect.DeepEqual(got, want) {
-			t.Errorf("tokenize(%q) = %q, _; want %q, _", spec.src, got, want)
-		}
-		if got, want := verb, ""; got != want {
-			t.Errorf("tokenize(%q) = _, %q; want _, %q", spec.src, got, want)
-		}
-
-		src := fmt.Sprintf("%s:%s", spec.src, "LOCK")
-		tokens, verb = tokenize(src)
-		if got, want := tokens, spec.tokens; !reflect.DeepEqual(got, want) {
-			t.Errorf("tokenize(%q) = %q, _; want %q, _", src, got, want)
-		}
-		if got, want := verb, "LOCK"; got != want {
-			t.Errorf("tokenize(%q) = _, %q; want _, %q", src, got, want)
-		}
-	}
-}
-
-func TestParseSegments(t *testing.T) {
-	flag.Set("v", "3")
-	for _, spec := range []struct {
-		tokens []string
-		want   []segment
-	}{
-		{
-			tokens: []string{"v1", eof},
-			want: []segment{
-				literal("v1"),
-			},
-		},
-		{
-			tokens: []string{"/", eof},
-			want: []segment{
-				wildcard{},
-			},
-		},
-		{
-			tokens: []string{"-._~!$&'()*+,;=:@", eof},
-			want: []segment{
-				literal("-._~!$&'()*+,;=:@"),
-			},
-		},
-		{
-			tokens: []string{"%e7%ac%ac%e4%b8%80%e7%89%88", eof},
-			want: []segment{
-				literal("%e7%ac%ac%e4%b8%80%e7%89%88"),
-			},
-		},
-		{
-			tokens: []string{"v1", "/", "*", eof},
-			want: []segment{
-				literal("v1"),
-				wildcard{},
-			},
-		},
-		{
-			tokens: []string{"v1", "/", "**", eof},
-			want: []segment{
-				literal("v1"),
-				deepWildcard{},
-			},
-		},
-		{
-			tokens: []string{"{", "name", "}", eof},
-			want: []segment{
-				variable{
-					path: "name",
-					segments: []segment{
-						wildcard{},
-					},
-				},
-			},
-		},
-		{
-			tokens: []string{"{", "name", "=", "*", "}", eof},
-			want: []segment{
-				variable{
-					path: "name",
-					segments: []segment{
-						wildcard{},
-					},
-				},
-			},
-		},
-		{
-			tokens: []string{"{", "field", ".", "nested", ".", "nested2", "=", "*", "}", eof},
-			want: []segment{
-				variable{
-					path: "field.nested.nested2",
-					segments: []segment{
-						wildcard{},
-					},
-				},
-			},
-		},
-		{
-			tokens: []string{"{", "name", "=", "a", "/", "b", "/", "*", "}", eof},
-			want: []segment{
-				variable{
-					path: "name",
-					segments: []segment{
-						literal("a"),
-						literal("b"),
-						wildcard{},
-					},
-				},
-			},
-		},
-		{
-			tokens: []string{
-				"v1", "/",
-				"{",
-				"name", ".", "nested", ".", "nested2",
-				"=",
-				"a", "/", "b", "/", "*",
-				"}", "/",
-				"o", "/",
-				"{",
-				"another_name",
-				"=",
-				"a", "/", "b", "/", "*", "/", "c",
-				"}", "/",
-				"**",
-				eof,
-			},
-			want: []segment{
-				literal("v1"),
-				variable{
-					path: "name.nested.nested2",
-					segments: []segment{
-						literal("a"),
-						literal("b"),
-						wildcard{},
-					},
-				},
-				literal("o"),
-				variable{
-					path: "another_name",
-					segments: []segment{
-						literal("a"),
-						literal("b"),
-						wildcard{},
-						literal("c"),
-					},
-				},
-				deepWildcard{},
-			},
-		},
-	} {
-		p := parser{tokens: spec.tokens}
-		segs, err := p.topLevelSegments()
-		if err != nil {
-			t.Errorf("parser{%q}.segments() failed with %v; want success", spec.tokens, err)
-			continue
-		}
-		if got, want := segs, spec.want; !reflect.DeepEqual(got, want) {
-			t.Errorf("parser{%q}.segments() = %#v; want %#v", spec.tokens, got, want)
-		}
-		if got := p.tokens; len(got) > 0 {
-			t.Errorf("p.tokens = %q; want []; spec.tokens=%q", got, spec.tokens)
-		}
-	}
-}
-
-func TestParseSegmentsWithErrors(t *testing.T) {
-	flag.Set("v", "3")
-	for _, spec := range []struct {
-		tokens []string
-	}{
-		{
-			// double slash
-			tokens: []string{"//", eof},
-		},
-		{
-			// invalid literal
-			tokens: []string{"a?b", eof},
-		},
-		{
-			// invalid percent-encoding
-			tokens: []string{"%", eof},
-		},
-		{
-			// invalid percent-encoding
-			tokens: []string{"%2", eof},
-		},
-		{
-			// invalid percent-encoding
-			tokens: []string{"a%2z", eof},
-		},
-		{
-			// empty segments
-			tokens: []string{eof},
-		},
-		{
-			// unterminated variable
-			tokens: []string{"{", "name", eof},
-		},
-		{
-			// unterminated variable
-			tokens: []string{"{", "name", "=", eof},
-		},
-		{
-			// unterminated variable
-			tokens: []string{"{", "name", "=", "*", eof},
-		},
-		{
-			// empty component in field path
-			tokens: []string{"{", "name", ".", "}", eof},
-		},
-		{
-			// empty component in field path
-			tokens: []string{"{", "name", ".", ".", "nested", "}", eof},
-		},
-		{
-			// invalid character in identifier
-			tokens: []string{"{", "field-name", "}", eof},
-		},
-		{
-			// no slash between segments
-			tokens: []string{"v1", "endpoint", eof},
-		},
-		{
-			// no slash between segments
-			tokens: []string{"v1", "{", "name", "}", eof},
-		},
-	} {
-		p := parser{tokens: spec.tokens}
-		segs, err := p.topLevelSegments()
-		if err == nil {
-			t.Errorf("parser{%q}.segments() succeeded; want InvalidTemplateError; accepted %#v", spec.tokens, segs)
-			continue
-		}
-		logger.Info(context.TODO(), err.Error())
-	}
-}

util/router/pattern.go

@@ -1,24 +0,0 @@
-package router
-
-// download from https://raw.githubusercontent.com/grpc-ecosystem/grpc-gateway/master/utilities/pattern.go
-
-// An OpCode is a opcode of compiled path patterns.
-type OpCode int
-
-// These constants are the valid values of OpCode.
-const (
-	// OpNop does nothing
-	OpNop = OpCode(iota)
-	// OpPush pushes a component to stack
-	OpPush
-	// OpLitPush pushes a component to stack if it matches to the literal
-	OpLitPush
-	// OpPushM concatenates the remaining components and pushes it to stack
-	OpPushM
-	// OpConcatN pops N items from stack, concatenates them and pushes it back to stack
-	OpConcatN
-	// OpCapture pops an item and binds it to the variable
-	OpCapture
-	// OpEnd is the least positive invalid opcode.
-	OpEnd
-)

util/router/router.go

@@ -1,32 +0,0 @@
-package router
-
-import (
-	"github.com/unistack-org/micro/v3/register"
-	"github.com/unistack-org/micro/v3/router"
-)
-
-type apiRouter struct {
-	router.Router
-	routes []router.Route
-}
-
-func (r *apiRouter) Lookup(...router.QueryOption) ([]router.Route, error) {
-	return r.routes, nil
-}
-
-func (r *apiRouter) String() string {
-	return "api"
-}
-
-// New router is a hack for API routing
-func New(srvs []*register.Service) router.Router {
-	var routes []router.Route
-
-	for _, srv := range srvs {
-		for _, n := range srv.Nodes {
-			routes = append(routes, router.Route{Address: n.Address, Metadata: n.Metadata})
-		}
-	}
-
-	return &apiRouter{routes: routes}
-}

util/router/runtime.go

@@ -1,284 +0,0 @@
-package router
-
-// download from https://raw.githubusercontent.com/grpc-ecosystem/grpc-gateway/master/runtime/pattern.go
-
-import (
-	"context"
-	"errors"
-	"fmt"
-	"strings"
-
-	"github.com/unistack-org/micro/v3/logger"
-)
-
-var (
-	// ErrNotMatch indicates that the given HTTP request path does not match to the pattern.
-	ErrNotMatch = errors.New("not match to the path pattern")
-	// ErrInvalidPattern indicates that the given definition of Pattern is not valid.
-	ErrInvalidPattern = errors.New("invalid pattern")
-)
-
-type rop struct {
-	code    OpCode
-	operand int
-}
-
-// Pattern is a template pattern of http request paths defined in github.com/googleapis/googleapis/google/api/http.proto.
-type Pattern struct {
-	verb string
-	// ops is a list of operations
-	ops []rop
-	// pool is a constant pool indexed by the operands or vars
-	pool []string
-	// vars is a list of variables names to be bound by this pattern
-	vars []string
-	// stacksize is the max depth of the stack
-	stacksize int
-	// tailLen is the length of the fixed-size segments after a deep wildcard
-	tailLen int
-	// assumeColonVerb indicates whether a path suffix after a final
-	// colon may only be interpreted as a verb.
-	assumeColonVerb bool
-}
-
-type patternOptions struct {
-	assumeColonVerb bool
-}
-
-// PatternOpt is an option for creating Patterns.
-type PatternOpt func(*patternOptions)
-
-// NewPattern returns a new Pattern from the given definition values.
-// "ops" is a sequence of op codes. "pool" is a constant pool.
-// "verb" is the verb part of the pattern. It is empty if the pattern does not have the part.
-// "version" must be 1 for now.
-// It returns an error if the given definition is invalid.
-//nolint:gocyclo
-func NewPattern(version int, ops []int, pool []string, verb string, opts ...PatternOpt) (Pattern, error) {
-	options := patternOptions{
-		assumeColonVerb: true,
-	}
-	for _, o := range opts {
-		o(&options)
-	}
-
-	if version != 1 {
-		if logger.V(logger.DebugLevel) {
-			logger.Debug(context.TODO(), "unsupported version: %d", version)
-		}
-		return Pattern{}, ErrInvalidPattern
-	}
-
-	l := len(ops)
-	if l%2 != 0 {
-		if logger.V(logger.DebugLevel) {
-			logger.Debug(context.TODO(), "odd number of ops codes: %d", l)
-		}
-		return Pattern{}, ErrInvalidPattern
-	}
-
-	var (
-		typedOps        []rop
-		stack, maxstack int
-		tailLen         int
-		pushMSeen       bool
-		vars            []string
-	)
-	for i := 0; i < l; i += 2 {
-		op := rop{code: OpCode(ops[i]), operand: ops[i+1]}
-		switch op.code {
-		case OpNop:
-			continue
-		case OpPush:
-			if pushMSeen {
-				tailLen++
-			}
-			stack++
-		case OpPushM:
-			if pushMSeen {
-				if logger.V(logger.TraceLevel) {
-					logger.Trace(context.TODO(), "pushM appears twice")
-				}
-				return Pattern{}, ErrInvalidPattern
-			}
-			pushMSeen = true
-			stack++
-		case OpLitPush:
-			if op.operand < 0 || len(pool) <= op.operand {
-				if logger.V(logger.TraceLevel) {
-					logger.Trace(context.TODO(), "negative literal index: %d", op.operand)
-				}
-				return Pattern{}, ErrInvalidPattern
-			}
-			if pushMSeen {
-				tailLen++
-			}
-			stack++
-		case OpConcatN:
-			if op.operand <= 0 {
-				if logger.V(logger.TraceLevel) {
-					logger.Trace(context.TODO(), "negative concat size: %d", op.operand)
-				}
-				return Pattern{}, ErrInvalidPattern
-			}
-			stack -= op.operand
-			if stack < 0 {
-				if logger.V(logger.TraceLevel) {
-					logger.Trace(context.TODO(), "stack underflow")
-				}
-				return Pattern{}, ErrInvalidPattern
-			}
-			stack++
-		case OpCapture:
-			if op.operand < 0 || len(pool) <= op.operand {
-				if logger.V(logger.TraceLevel) {
-					logger.Trace(context.TODO(), "variable name index out of bound: %d", op.operand)
-				}
-				return Pattern{}, ErrInvalidPattern
-			}
-			v := pool[op.operand]
-			op.operand = len(vars)
-			vars = append(vars, v)
-			stack--
-			if stack < 0 {
-				if logger.V(logger.DebugLevel) {
-					logger.Trace(context.TODO(), "stack underflow")
-				}
-				return Pattern{}, ErrInvalidPattern
-			}
-		default:
-			if logger.V(logger.DebugLevel) {
-				logger.Trace(context.TODO(), "invalid opcode: %d", op.code)
-			}
-			return Pattern{}, ErrInvalidPattern
-		}
-
-		if maxstack < stack {
-			maxstack = stack
-		}
-		typedOps = append(typedOps, op)
-	}
-	return Pattern{
-		ops:             typedOps,
-		pool:            pool,
-		vars:            vars,
-		stacksize:       maxstack,
-		tailLen:         tailLen,
-		verb:            verb,
-		assumeColonVerb: options.assumeColonVerb,
-	}, nil
-}
-
-// MustPattern is a helper function which makes it easier to call NewPattern in variable initialization.
-func MustPattern(p Pattern, err error) Pattern {
-	if err != nil {
-		if logger.V(logger.FatalLevel) {
-			logger.Fatal(context.TODO(), "Pattern initialization failed: %v", err)
-		}
-	}
-	return p
-}
-
-// Match examines components if it matches to the Pattern.
-// If it matches, the function returns a mapping from field paths to their captured values.
-// If otherwise, the function returns an error.
-//nolint:gocyclo
-func (p Pattern) Match(components []string, verb string) (map[string]string, error) {
-	if p.verb != verb {
-		if p.assumeColonVerb || p.verb != "" {
-			return nil, ErrNotMatch
-		}
-		if len(components) == 0 {
-			components = []string{":" + verb}
-		} else {
-			components = append([]string{}, components...)
-			components[len(components)-1] += ":" + verb
-		}
-	}
-
-	var pos int
-	stack := make([]string, 0, p.stacksize)
-	captured := make([]string, len(p.vars))
-	l := len(components)
-	for _, op := range p.ops {
-		switch op.code {
-		case OpNop:
-			continue
-		case OpPush, OpLitPush:
-			if pos >= l {
-				return nil, ErrNotMatch
-			}
-			c := components[pos]
-			if op.code == OpLitPush {
-				if lit := p.pool[op.operand]; c != lit {
-					return nil, ErrNotMatch
-				}
-			}
-			stack = append(stack, c)
-			pos++
-		case OpPushM:
-			end := len(components)
-			if end < pos+p.tailLen {
-				return nil, ErrNotMatch
-			}
-			end -= p.tailLen
-			stack = append(stack, strings.Join(components[pos:end], "/"))
-			pos = end
-		case OpConcatN:
-			n := op.operand
-			l := len(stack) - n
-			stack = append(stack[:l], strings.Join(stack[l:], "/"))
-		case OpCapture:
-			n := len(stack) - 1
-			captured[op.operand] = stack[n]
-			stack = stack[:n]
-		}
-	}
-	if pos < l {
-		return nil, ErrNotMatch
-	}
-	bindings := make(map[string]string, len(captured))
-	for i, val := range captured {
-		bindings[p.vars[i]] = val
-	}
-	return bindings, nil
-}
-
-// Verb returns the verb part of the Pattern.
-func (p Pattern) Verb() string { return p.verb }
-
-func (p Pattern) String() string {
-	var stack []string
-	for _, op := range p.ops {
-		switch op.code {
-		case OpNop:
-			continue
-		case OpPush:
-			stack = append(stack, "*")
-		case OpLitPush:
-			stack = append(stack, p.pool[op.operand])
-		case OpPushM:
-			stack = append(stack, "**")
-		case OpConcatN:
-			n := op.operand
-			l := len(stack) - n
-			stack = append(stack[:l], strings.Join(stack[l:], "/"))
-		case OpCapture:
-			n := len(stack) - 1
-			stack[n] = fmt.Sprintf("{%s=%s}", p.vars[op.operand], stack[n])
-		}
-	}
-	segs := strings.Join(stack, "/")
-	if p.verb != "" {
-		return fmt.Sprintf("/%s:%s", segs, p.verb)
-	}
-	return "/" + segs
-}
-
-// AssumeColonVerbOpt indicates whether a path suffix after a final
-// colon may only be interpreted as a verb.
-func AssumeColonVerbOpt(val bool) PatternOpt {
-	return PatternOpt(func(o *patternOptions) {
-		o.assumeColonVerb = val
-	})
-}