merge stable changes (#61)

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/build.yml

@@ -3,6 +3,7 @@ on:
   push:
     branches:
     - master
+    - v3
 jobs:
   test:
     name: test

.github/workflows/codeql-analysis.yml

@@ -0,0 +1,78 @@
+# 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, v3 ]
+  pull_request:
+    # The branches below must be a subset of the branches above
+    branches: [ master, v3 ]
+  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
+      uses: actions/checkout@v2
+    - name: setup
+      uses: actions/setup-go@v2
+      with:
+        go-version: 1.16
+    # Initializes the CodeQL tools for scanning.
+    - name: init
+      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: analyze
+      uses: github/codeql-action/analyze@v1

.github/workflows/dependabot-automerge.yml

@@ -0,0 +1,31 @@
+name: "prautomerge"
+
+on:
+  pull_request_target:
+    types: [assigned, opened, synchronize, reopened]
+
+permissions:
+  pull-requests: write
+  contents: write
+
+jobs:
+  dependabot:
+    runs-on: ubuntu-latest
+    if: ${{ github.actor == 'dependabot[bot]' }}
+    steps:
+      - name: metadata
+        id: metadata
+        uses: dependabot/fetch-metadata@v1.1.1
+        with:
+          github-token: "${{ secrets.TOKEN }}"
+      - name: approve
+        run: gh pr review --approve "$PR_URL"
+        env:
+          PR_URL: ${{github.event.pull_request.html_url}}
+          GITHUB_TOKEN: ${{secrets.TOKEN}}
+      - name: merge
+        if: ${{contains(steps.metadata.outputs.dependency-names, 'go.unistack.org')}}
+        run: gh pr merge --auto --merge "$PR_URL"
+        env:
+          PR_URL: ${{github.event.pull_request.html_url}}
+          GITHUB_TOKEN: ${{secrets.TOKEN}}

.github/workflows/pr.yml

@@ -3,6 +3,7 @@ on:
   pull_request:
     branches:
     - master
+    - v3
 jobs:
   test:
     name: test

.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

@@ -1,15 +1,16 @@
-package api
+package api // import "go.unistack.org/micro/v3/api"
 
 import (
 	"errors"
 	"regexp"
 	"strings"
 
-	"github.com/unistack-org/micro/v3/metadata"
-	"github.com/unistack-org/micro/v3/register"
-	"github.com/unistack-org/micro/v3/server"
+	"go.unistack.org/micro/v3/metadata"
+	"go.unistack.org/micro/v3/register"
+	"go.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")
 		}
 	}

api/handler/handler.go

@@ -1,5 +1,5 @@
 // Package handler provides http handlers
-package handler
+package handler // import "go.unistack.org/micro/v3/api/handler"
 
 import (
 	"net/http"

api/handler/options.go

@@ -1,9 +1,9 @@
 package handler
 
 import (
-	"github.com/unistack-org/micro/v3/api/router"
-	"github.com/unistack-org/micro/v3/client"
-	"github.com/unistack-org/micro/v3/logger"
+	"go.unistack.org/micro/v3/api/router"
+	"go.unistack.org/micro/v3/client"
+	"go.unistack.org/micro/v3/logger"
 )
 
 // DefaultMaxRecvSize specifies max recv size for handler

api/resolver/grpc/grpc.go

@@ -1,12 +1,12 @@
 // Package grpc resolves a grpc service like /greeter.Say/Hello to greeter service
-package grpc
+package grpc // import "go.unistack.org/micro/v3/api/resolver/grpc"
 
 import (
 	"errors"
 	"net/http"
 	"strings"
 
-	"github.com/unistack-org/micro/v3/api/resolver"
+	"go.unistack.org/micro/v3/api/resolver"
 )
 
 // Resolver struct

api/resolver/host/host.go

@@ -1,10 +1,10 @@
 // Package host resolves using http host
-package host
+package host // import "go.unistack.org/micro/v3/api/resolver/host"
 
 import (
 	"net/http"
 
-	"github.com/unistack-org/micro/v3/api/resolver"
+	"go.unistack.org/micro/v3/api/resolver"
 )
 
 type hostResolver struct {

api/resolver/options.go

@@ -3,7 +3,7 @@ package resolver
 import (
 	"context"
 
-	"github.com/unistack-org/micro/v3/register"
+	"go.unistack.org/micro/v3/register"
 )
 
 // Options struct

api/resolver/path/path.go

@@ -1,11 +1,11 @@
 // Package path resolves using http path
-package path
+package path // import "go.unistack.org/micro/v3/api/resolver/path"
 
 import (
 	"net/http"
 	"strings"
 
-	"github.com/unistack-org/micro/v3/api/resolver"
+	"go.unistack.org/micro/v3/api/resolver"
 )
 
 // Resolver the path resolver

api/resolver/resolver.go

@@ -1,5 +1,5 @@
 // Package resolver resolves a http request to an endpoint
-package resolver
+package resolver // import "go.unistack.org/micro/v3/api/resolver"
 
 import (
 	"errors"

api/resolver/subdomain/subdomain.go

@@ -1,14 +1,14 @@
 // Package subdomain is a resolver which uses the subdomain to determine the domain to route to. It
 // offloads the endpoint resolution to a child resolver which is provided in New.
-package subdomain
+package subdomain // import "go.unistack.org/micro/v3/api/resolver/subdomain"
 
 import (
 	"net"
 	"net/http"
 	"strings"
 
-	"github.com/unistack-org/micro/v3/api/resolver"
-	"github.com/unistack-org/micro/v3/logger"
+	"go.unistack.org/micro/v3/api/resolver"
+	"go.unistack.org/micro/v3/logger"
 	"golang.org/x/net/publicsuffix"
 )
 

api/resolver/subdomain/subdomain_test.go

@@ -5,7 +5,7 @@ import (
 	"net/url"
 	"testing"
 
-	"github.com/unistack-org/micro/v3/api/resolver/vpath"
+	"go.unistack.org/micro/v3/api/resolver/vpath"
 )
 
 func TestResolve(t *testing.T) {

api/resolver/vpath/vpath.go

@@ -1,5 +1,5 @@
 // Package vpath resolves using http path and recognised versioned urls
-package vpath
+package vpath // import "go.unistack.org/micro/v3/api/resolver/vpath"
 
 import (
 	"errors"
@@ -7,7 +7,7 @@ import (
 	"regexp"
 	"strings"
 
-	"github.com/unistack-org/micro/v3/api/resolver"
+	"go.unistack.org/micro/v3/api/resolver"
 )
 
 // NewResolver creates new vpath api resolver

api/router/options.go

@@ -3,10 +3,10 @@ package router
 import (
 	"context"
 
-	"github.com/unistack-org/micro/v3/api/resolver"
-	"github.com/unistack-org/micro/v3/api/resolver/vpath"
-	"github.com/unistack-org/micro/v3/logger"
-	"github.com/unistack-org/micro/v3/register"
+	"go.unistack.org/micro/v3/api/resolver"
+	"go.unistack.org/micro/v3/api/resolver/vpath"
+	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v3/register"
 )
 
 // Options holds the options for api router

api/router/router.go

@@ -1,10 +1,10 @@
 // Package router provides api service routing
-package router
+package router // import "go.unistack.org/micro/v3/api/router"
 
 import (
 	"net/http"
 
-	"github.com/unistack-org/micro/v3/api"
+	"go.unistack.org/micro/v3/api"
 )
 
 // DefaultRouter contains default router implementation

auth/auth.go

@@ -1,12 +1,12 @@
 // Package auth provides authentication and authorization capability
-package auth
+package auth // import "go.unistack.org/micro/v3/auth"
 
 import (
 	"context"
 	"errors"
 	"time"
 
-	"github.com/unistack-org/micro/v3/metadata"
+	"go.unistack.org/micro/v3/metadata"
 )
 
 const (
@@ -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"
+	"go.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

auth/options.go

@@ -4,11 +4,11 @@ import (
 	"context"
 	"time"
 
-	"github.com/unistack-org/micro/v3/logger"
-	"github.com/unistack-org/micro/v3/metadata"
-	"github.com/unistack-org/micro/v3/meter"
-	"github.com/unistack-org/micro/v3/store"
-	"github.com/unistack-org/micro/v3/tracer"
+	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v3/metadata"
+	"go.unistack.org/micro/v3/meter"
+	"go.unistack.org/micro/v3/store"
+	"go.unistack.org/micro/v3/tracer"
 )
 
 // NewOptions creates Options struct from slice of options

broker/broker.go

@@ -1,38 +1,86 @@
 // Package broker is an interface used for asynchronous messaging
-package broker
+package broker // import "go.unistack.org/micro/v3/broker"
 
 import (
 	"context"
 	"errors"
 
-	"github.com/unistack-org/micro/v3/metadata"
+	"go.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.
@@ -42,7 +90,7 @@ type RawMessage []byte
 // MarshalJSON returns m as the JSON encoding of m.
 func (m *RawMessage) MarshalJSON() ([]byte, error) {
 	if m == nil {
-		return nil, nil
+		return []byte("null"), nil
 	}
 	return *m, nil
 }
@@ -58,13 +106,25 @@ func (m *RawMessage) UnmarshalJSON(data []byte) error {
 
 // Message is used to transfer data
 type Message struct {
-	Header metadata.Metadata // contains message metadata
-	Body   RawMessage        // 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"
-	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"
+	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v3/metadata"
+	maddr "go.unistack.org/micro/v3/util/addr"
+	"go.unistack.org/micro/v3/util/id"
+	mnet "go.unistack.org/micro/v3/util/net"
+	"go.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"
+
+	"go.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"`),
 		}
+		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

@@ -3,12 +3,13 @@ package broker
 import (
 	"context"
 	"crypto/tls"
+	"time"
 
-	"github.com/unistack-org/micro/v3/codec"
-	"github.com/unistack-org/micro/v3/logger"
-	"github.com/unistack-org/micro/v3/meter"
-	"github.com/unistack-org/micro/v3/register"
-	"github.com/unistack-org/micro/v3/tracer"
+	"go.unistack.org/micro/v3/codec"
+	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v3/meter"
+	"go.unistack.org/micro/v3/register"
+	"go.unistack.org/micro/v3/tracer"
 )
 
 // Options struct
@@ -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
+}

build/build.go

@@ -1,5 +1,5 @@
 // Package build is for building source into a package
-package build
+package build // import "go.unistack.org/micro/v3/build"
 
 // Build is an interface for building packages
 type Build interface {

client/backoff.go

@@ -4,7 +4,7 @@ import (
 	"context"
 	"time"
 
-	"github.com/unistack-org/micro/v3/util/backoff"
+	"go.unistack.org/micro/v3/util/backoff"
 )
 
 // BackoffFunc is the backoff call func

client/client.go

@@ -1,12 +1,12 @@
 // Package client is an interface for an RPC client
-package client
+package client // import "go.unistack.org/micro/v3/client"
 
 import (
 	"context"
 	"time"
 
-	"github.com/unistack-org/micro/v3/codec"
-	"github.com/unistack-org/micro/v3/metadata"
+	"go.unistack.org/micro/v3/codec"
+	"go.unistack.org/micro/v3/metadata"
 )
 
 var (
@@ -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/lookup.go

@@ -4,8 +4,8 @@ import (
 	"context"
 	"sort"
 
-	"github.com/unistack-org/micro/v3/errors"
-	"github.com/unistack-org/micro/v3/router"
+	"go.unistack.org/micro/v3/errors"
+	"go.unistack.org/micro/v3/router"
 )
 
 // LookupFunc is used to lookup routes for a service

client/noop.go

@@ -3,10 +3,10 @@ package client
 import (
 	"context"
 
-	"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/metadata"
+	"go.unistack.org/micro/v3/broker"
+	"go.unistack.org/micro/v3/codec"
+	"go.unistack.org/micro/v3/errors"
+	"go.unistack.org/micro/v3/metadata"
 )
 
 // DefaultCodecs will be used to encode/decode data
@@ -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

@@ -5,20 +5,22 @@ import (
 	"crypto/tls"
 	"time"
 
-	"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/meter"
-	"github.com/unistack-org/micro/v3/network/transport"
-	"github.com/unistack-org/micro/v3/register"
-	"github.com/unistack-org/micro/v3/router"
-	"github.com/unistack-org/micro/v3/selector"
-	"github.com/unistack-org/micro/v3/selector/random"
-	"github.com/unistack-org/micro/v3/tracer"
+	"go.unistack.org/micro/v3/broker"
+	"go.unistack.org/micro/v3/codec"
+	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v3/meter"
+	"go.unistack.org/micro/v3/network/transport"
+	"go.unistack.org/micro/v3/register"
+	"go.unistack.org/micro/v3/router"
+	"go.unistack.org/micro/v3/selector"
+	"go.unistack.org/micro/v3/selector/random"
+	"go.unistack.org/micro/v3/tracer"
 )
 
 // 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) {

client/retry.go

@@ -3,7 +3,7 @@ package client
 import (
 	"context"
 
-	"github.com/unistack-org/micro/v3/errors"
+	"go.unistack.org/micro/v3/errors"
 )
 
 // RetryFunc that returning either false or a non-nil error will result in the call not being retried

client/test_request.go

@@ -1,7 +1,7 @@
 package client
 
 import (
-	"github.com/unistack-org/micro/v3/codec"
+	"go.unistack.org/micro/v3/codec"
 )
 
 type testRequest struct {

codec/codec.go

@@ -1,11 +1,11 @@
 // Package codec is an interface for encoding messages
-package codec
+package codec // import "go.unistack.org/micro/v3/codec"
 
 import (
 	"errors"
 	"io"
 
-	"github.com/unistack-org/micro/v3/metadata"
+	"go.unistack.org/micro/v3/metadata"
 )
 
 // Message types
@@ -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/frame.proto

@@ -17,7 +17,7 @@ syntax = "proto3";
 package micro.codec;
 
 option cc_enable_arenas = true;
-option go_package = "github.com/unistack-org/micro/v3/codec;codec";
+option go_package = "go.unistack.org/micro/v3/codec;codec";
 option java_multiple_files = true;
 option java_outer_classname = "MicroCodec";
 option java_package = "micro.codec";

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

@@ -1,9 +1,11 @@
 package codec
 
 import (
-	"github.com/unistack-org/micro/v3/logger"
-	"github.com/unistack-org/micro/v3/meter"
-	"github.com/unistack-org/micro/v3/tracer"
+	"context"
+
+	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v3/meter"
+	"go.unistack.org/micro/v3/tracer"
 )
 
 // Option func
@@ -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

@@ -1,14 +1,21 @@
 // Package config is an interface for dynamic configuration.
-package config
+package config // import "go.unistack.org/micro/v3/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")
@@ -30,15 +37,17 @@ 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
 }
 
@@ -55,3 +64,53 @@ func Load(ctx context.Context, cs []Config, opts ...LoadOption) error {
 	}
 	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/context.go

@@ -32,3 +32,23 @@ func SetOption(k, v interface{}) Option {
 		o.Context = context.WithValue(o.Context, k, v)
 	}
 }
+
+// SetSaveOption returns a function to setup a context with given value
+func SetSaveOption(k, v interface{}) SaveOption {
+	return func(o *SaveOptions) {
+		if o.Context == nil {
+			o.Context = context.Background()
+		}
+		o.Context = context.WithValue(o.Context, k, v)
+	}
+}
+
+// SetLoadOption returns a function to setup a context with given value
+func SetLoadOption(k, v interface{}) LoadOption {
+	return func(o *LoadOptions) {
+		if o.Context == nil {
+			o.Context = context.Background()
+		}
+		o.Context = context.WithValue(o.Context, k, v)
+	}
+}

config/default.go

@@ -2,12 +2,13 @@ package config
 
 import (
 	"context"
+	"fmt"
 	"reflect"
 	"strconv"
 	"strings"
 
 	"github.com/imdario/mergo"
-	rutil "github.com/unistack-org/micro/v3/util/reflect"
+	rutil "go.unistack.org/micro/v3/util/reflect"
 )
 
 type defaultConfig struct {
@@ -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

@@ -5,7 +5,7 @@ import (
 	"fmt"
 	"testing"
 
-	"github.com/unistack-org/micro/v3/config"
+	"go.unistack.org/micro/v3/config"
 )
 
 type Cfg struct {
@@ -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

@@ -2,11 +2,12 @@ package config
 
 import (
 	"context"
+	"time"
 
-	"github.com/unistack-org/micro/v3/codec"
-	"github.com/unistack-org/micro/v3/logger"
-	"github.com/unistack-org/micro/v3/meter"
-	"github.com/unistack-org/micro/v3/tracer"
+	"go.unistack.org/micro/v3/codec"
+	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v3/meter"
+	"go.unistack.org/micro/v3/tracer"
 )
 
 // Options hold the config options
@@ -62,8 +63,10 @@ type LoadOption func(o *LoadOptions)
 
 // LoadOptions struct
 type LoadOptions struct {
+	Struct   interface{}
 	Override bool
 	Append   bool
+	Context  context.Context
 }
 
 func NewLoadOptions(opts ...LoadOption) LoadOptions {
@@ -88,13 +91,30 @@ 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{}
+	Context context.Context
 }
 
+// SaveStruct override struct for save to config
+func SaveStruct(src interface{}) SaveOption {
+	return func(o *SaveOptions) {
+		o.Struct = src
+	}
+}
+
+// NewSaveOptions fill SaveOptions struct
 func NewSaveOptions(opts ...SaveOption) SaveOptions {
 	options := SaveOptions{}
 	for _, o := range opts {
@@ -186,3 +206,60 @@ 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

@@ -1,6 +1,6 @@
 // Package errors provides a way to return detailed information
 // for an RPC request error. The error is normally JSON encoded.
-package errors
+package errors // import "go.unistack.org/micro/v3/errors"
 
 import (
 	"encoding/json"
@@ -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 {

event.go

@@ -3,7 +3,7 @@ package micro
 import (
 	"context"
 
-	"github.com/unistack-org/micro/v3/client"
+	"go.unistack.org/micro/v3/client"
 )
 
 // Event is used to publish messages to a topic

flow/default.go

@@ -3,12 +3,16 @@ package flow
 import (
 	"context"
 	"fmt"
+	"path/filepath"
 	"sync"
 
-	"github.com/google/uuid"
 	"github.com/silas/dag"
-	"github.com/unistack-org/micro/v3/client"
-	"github.com/unistack-org/micro/v3/codec"
+	"go.unistack.org/micro/v3/client"
+	"go.unistack.org/micro/v3/codec"
+	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v3/metadata"
+	"go.unistack.org/micro/v3/store"
+	"go.unistack.org/micro/v3/util/id"
 )
 
 type microFlow struct {
@@ -16,49 +20,94 @@ type microFlow struct {
 }
 
 type microWorkflow struct {
-	id   string
-	g    *dag.AcyclicGraph
-	init bool
+	opts   Options
+	g      *dag.AcyclicGraph
+	steps  map[string]Step
+	id     string
+	status Status
 	sync.RWMutex
-	opts  Options
-	steps map[string]Step
+	init bool
 }
 
 func (w *microWorkflow) ID() string {
 	return w.id
 }
 
-func (w *microWorkflow) Steps() [][]Step {
-	return nil
+func (w *microWorkflow) Steps() ([][]Step, error) {
+	return w.getSteps("", false)
 }
 
-func (w *microWorkflow) AppendSteps(ctx context.Context, steps ...Step) error {
-	return nil
+func (w *microWorkflow) Status() Status {
+	return w.status
 }
 
-func (w *microWorkflow) RemoveSteps(ctx context.Context, steps ...Step) error {
-	return nil
-}
-
-func (w *microWorkflow) Execute(ctx context.Context, req interface{}, opts ...ExecuteOption) (string, error) {
+func (w *microWorkflow) AppendSteps(steps ...Step) error {
 	w.Lock()
-	if !w.init {
-		if err := w.g.Validate(); err != nil {
-			w.Unlock()
-			return "", err
-		}
-		w.g.TransitiveReduction()
-		w.init = true
+
+	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()
 
-	uid, err := uuid.NewRandom()
-	if err != nil {
-		return "", err
+	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)
 	}
 
-	options := NewExecuteOptions(opts...)
+	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)
@@ -73,59 +122,231 @@ func (w *microWorkflow) Execute(ctx context.Context, req interface{}, opts ...Ex
 		return nil
 	}
 
-	var root dag.Vertex
-	if options.Start != "" {
+	if start != "" {
 		var ok bool
 		w.RLock()
-		root, ok = w.steps[options.Start]
+		root, ok = w.steps[start]
 		w.RUnlock()
 		if !ok {
-			return "", ErrStepNotExists
+			return nil, ErrStepNotExists
 		}
 	} else {
 		root, err = w.g.Root()
 		if err != nil {
-			return "", err
+			return nil, err
 		}
 	}
-	if options.Reverse {
+
+	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)
-	defer close(cherr)
+	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), ExecuteStore(w.opts.Store))
+
+	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 {
-			wg.Add(len(steps[idx]))
 			for nidx := range steps[idx] {
-				go func(step Step) {
-					defer wg.Done()
-					if err = step.Execute(nctx, req, nopts...); err != nil {
-						cherr <- err
-						cancel()
+				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
 					}
-				}(steps[idx][nidx])
+					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
+					}
+				}
 			}
-			wg.Wait()
 		}
-		cherr <- nil
+		close(done)
 	}()
 
-	err = <-cherr
+	if options.Async {
+		return eid, nil
+	}
 
-	return uid.String(), err
+	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 {
@@ -204,9 +425,20 @@ func (f *microFlow) WorkflowLoad(ctx context.Context, id string) (Workflow, erro
 }
 
 type microCallStep struct {
-	opts    StepOptions
+	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 {
@@ -247,23 +479,49 @@ func (s *microCallStep) Hashcode() interface{} {
 	return s.String()
 }
 
-func (s *microCallStep) Execute(ctx context.Context, req interface{}, opts ...ExecuteOption) error {
+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 fmt.Errorf("client not set")
+		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))
+		copts = append(copts,
+			client.WithRequestTimeout(options.Timeout),
+			client.WithDialTimeout(options.Timeout))
 	}
-	err := options.Client.Call(ctx, options.Client.NewRequest(s.service, s.method, req), rsp)
-	return err
+	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 {
-	opts  StepOptions
-	topic string
+	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 {
@@ -293,7 +551,7 @@ func (s *microPublishStep) String() string {
 	if s.opts.ID != "" {
 		return s.opts.ID
 	}
-	return fmt.Sprintf("%s", s.topic)
+	return s.topic
 }
 
 func (s *microPublishStep) Name() string {
@@ -304,13 +562,21 @@ func (s *microPublishStep) Hashcode() interface{} {
 	return s.String()
 }
 
-func (s *microPublishStep) Execute(ctx context.Context, req interface{}, opts ...ExecuteOption) error {
-	return nil
+func (s *microPublishStep) GetStatus() Status {
+	return s.status
 }
 
-func NewCallStep(service string, method string, opts ...StepOption) Step {
+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: method, opts: options}
+	return &microCallStep{service: service, method: name + "." + method, opts: options}
 }
 
 func NewPublishStep(topic string, opts ...StepOption) Step {

flow/flow.go

@@ -1,15 +1,46 @@
 // Package flow is an interface used for saga pattern microservice workflow
-package flow
+package flow // import "go.unistack.org/micro/v3/flow"
 
 import (
 	"context"
 	"errors"
+	"sync"
+	"sync/atomic"
+
+	"go.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
@@ -17,7 +48,7 @@ type Step interface {
 	// Endpoint returns rpc endpoint service_name.service_method or broker topic
 	Endpoint() string
 	// Execute step run
-	Execute(ctx context.Context, req interface{}, opts ...ExecuteOption) error
+	Execute(ctx context.Context, req *Message, opts ...ExecuteOption) (*Message, error)
 	// Requires returns dependent steps
 	Requires() []string
 	// Options returns step options
@@ -26,20 +57,70 @@ type Step interface {
 	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 {
 	// ID returns id of the workflow
 	ID() string
-	// Steps returns steps slice where parallel steps returned on the same level
-	Steps() [][]Step
 	// Execute workflow with args, return execution id and error
-	Execute(ctx context.Context, req interface{}, opts ...ExecuteOption) (string, error)
+	Execute(ctx context.Context, req *Message, opts ...ExecuteOption) (string, error)
 	// RemoveSteps remove steps from workflow
-	RemoveSteps(ctx context.Context, steps ...Step) error
+	RemoveSteps(steps ...Step) error
 	// AppendSteps append steps to workflow
-	AppendSteps(ctx context.Context, steps ...Step) error
+	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
@@ -57,3 +138,15 @@ type Flow interface {
 	// 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

@@ -4,11 +4,11 @@ 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"
+	"go.unistack.org/micro/v3/client"
+	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v3/meter"
+	"go.unistack.org/micro/v3/store"
+	"go.unistack.org/micro/v3/tracer"
 )
 
 // Option func
@@ -96,8 +96,8 @@ type WorkflowOption func(*WorkflowOptions)
 
 // WorkflowOptions holds workflow options
 type WorkflowOptions struct {
-	ID      string
 	Context context.Context
+	ID      string
 }
 
 // WorkflowID set workflow id
@@ -116,16 +116,16 @@ type ExecuteOptions struct {
 	Logger logger.Logger
 	// Meter holds the meter
 	Meter meter.Meter
-	// Store used for intermediate results
-	Store store.Store
 	// Context can be used to abort execution or pass additional opts
 	Context context.Context
 	// Start step
 	Start string
-	// Reverse execution
-	Reverse bool
 	// Timeout for execution
 	Timeout time.Duration
+	// Reverse execution
+	Reverse bool
+	// Async enables async execution
+	Async bool
 }
 
 type ExecuteOption func(*ExecuteOptions)
@@ -154,12 +154,6 @@ func ExecuteMeter(m meter.Meter) ExecuteOption {
 	}
 }
 
-func ExecuteStore(s store.Store) ExecuteOption {
-	return func(o *ExecuteOptions) {
-		o.Store = s
-	}
-}
-
 func ExecuteContext(ctx context.Context) ExecuteOption {
 	return func(o *ExecuteOptions) {
 		o.Context = ctx
@@ -178,8 +172,20 @@ func ExecuteTimeout(td time.Duration) ExecuteOption {
 	}
 }
 
+func ExecuteAsync(b bool) ExecuteOption {
+	return func(o *ExecuteOptions) {
+		o.Async = b
+	}
+}
+
 func NewExecuteOptions(opts ...ExecuteOption) ExecuteOptions {
-	options := ExecuteOptions{}
+	options := ExecuteOptions{
+		Client:  client.DefaultClient,
+		Logger:  logger.DefaultLogger,
+		Tracer:  tracer.DefaultTracer,
+		Meter:   meter.DefaultMeter,
+		Context: context.Background(),
+	}
 	for _, o := range opts {
 		o(&options)
 	}
@@ -187,16 +193,18 @@ func NewExecuteOptions(opts ...ExecuteOption) ExecuteOptions {
 }
 
 type StepOptions struct {
-	ID       string
 	Context  context.Context
-	Requires []string
 	Fallback string
+	ID       string
+	Requires []string
 }
 
 type StepOption func(*StepOptions)
 
 func NewStepOptions(opts ...StepOption) StepOptions {
-	options := StepOptions{Context: context.Background()}
+	options := StepOptions{
+		Context: context.Background(),
+	}
 	for _, o := range opts {
 		o(&options)
 	}

function.go

@@ -6,7 +6,7 @@ import (
 	"context"
 	"time"
 
-	"github.com/unistack-org/micro/v3/server"
+	"go.unistack.org/micro/v3/server"
 )
 
 // Function is a one time executing Service

function_test.go

@@ -8,7 +8,7 @@ import (
 	"sync"
 	"testing"
 
-	"github.com/unistack-org/micro/v3/register"
+	"go.unistack.org/micro/v3/register"
 )
 
 func TestFunction(t *testing.T) {

go.mod

@@ -1,13 +1,14 @@
-module github.com/unistack-org/micro/v3
+module go.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
+	go.unistack.org/micro-proto/v3 v3.1.0
+	golang.org/x/net v0.0.0-20210928044308-7d9f5e0b762b
+	golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 // indirect
 )

go.sum

@@ -1,22 +1,31 @@
-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 v4.1.0 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=
+go.unistack.org/micro-proto/v3 v3.1.0 h1:q39FwjFiRZn+Ux/tt+d3bJTmDtsQQWa+3SLYVo1vLfA=
+go.unistack.org/micro-proto/v3 v3.1.0/go.mod h1:DpRhYCBXlmSJ/AAXTmntvlh7kQkYU6eFvlmYAx4BQS8=
+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
+package logger // import "go.unistack.org/micro/v3/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 "go.unistack.org/micro/v3/logger/wrapper"
+
+import (
+	"context"
+	"reflect"
+
+	rutil "go.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)...)
+	}
+}

logger/wrapper/wrapper.go

@@ -5,9 +5,9 @@ import (
 	"context"
 	"fmt"
 
-	"github.com/unistack-org/micro/v3/client"
-	"github.com/unistack-org/micro/v3/logger"
-	"github.com/unistack-org/micro/v3/server"
+	"go.unistack.org/micro/v3/client"
+	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v3/server"
 )
 
 var (

metadata/metadata.go

@@ -1,13 +1,25 @@
 // Package metadata is a way of defining message headers
-package metadata
+package metadata // import "go.unistack.org/micro/v3/metadata"
 
 import (
 	"net/textproto"
 	"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 go.unistack.org/micro-proto/v3) --go-micro_out='components=micro|http|server',standalone=false,debug=true,paths=source_relative:./handler handler/handler.proto"
+
+import (
+
+	// import required packages
+	_ "go.unistack.org/micro-proto/v3/api"
+
+	// import required packages
+	_ "go.unistack.org/micro-proto/v3/openapiv3"
+)

meter/handler/handler.go

@@ -1,12 +1,12 @@
-package handler
+package handler // import "go.unistack.org/micro/v3/meter/handler"
 
 import (
 	"bytes"
 	"context"
 
-	"github.com/unistack-org/micro/v3/codec"
-	"github.com/unistack-org/micro/v3/errors"
-	"github.com/unistack-org/micro/v3/meter"
+	"go.unistack.org/micro/v3/codec"
+	"go.unistack.org/micro/v3/errors"
+	"go.unistack.org/micro/v3/meter"
 )
 
 // guard to fail early

meter/handler/handler.proto

@@ -1,27 +1,23 @@
 syntax = "proto3";
 
 package micro.meter.handler;
-option go_package = "github.com/unistack-org/micro/v3/meter/handler;handler";
+option go_package = "go.unistack.org/micro/v3/meter/handler;handler";
 
 import "api/annotations.proto";
-import "openapiv2/annotations.proto";
+import "openapiv3/annotations.proto";
 import "codec/frame.proto";
 
 service Meter {
 	rpc Metrics(micro.codec.Frame) returns (micro.codec.Frame) {
-		option (micro.openapiv2.openapiv2_operation) = {
+		option (micro.openapiv3.openapiv3_operation) = {
       operation_id: "Metrics";
-        responses: {
-          key: "default";
-          value: {
-            description: "Error response";
-            schema: {
-              json_schema: {
-                ref: "micro.codec.Frame";
-              }
-            }
-          }
-        }
+      responses: {
+        default: {
+          reference: {
+            _ref: "micro.codec.Frame";
+          };
+        };
+      };
     };
 		option (micro.api.http) = { get: "/metrics"; };
   };

meter/handler/handler_micro.pb.go

@@ -1,22 +1,30 @@
-// Code generated by protoc-gen-micro
+// Code generated by protoc-gen-go-micro. DO NOT EDIT.
+// protoc-gen-go-micro version: v3.5.2
 // source: handler.proto
+
 package handler
 
 import (
 	context "context"
-	api "github.com/unistack-org/micro/v3/api"
-	codec "github.com/unistack-org/micro/v3/codec"
+	api "go.unistack.org/micro/v3/api"
+	codec "go.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

@@ -1,12 +1,14 @@
-// Code generated by protoc-gen-micro
+// Code generated by protoc-gen-go-micro. DO NOT EDIT.
+// protoc-gen-go-micro version: v3.5.2
 // 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"
+	api "go.unistack.org/micro/v3/api"
+	codec "go.unistack.org/micro/v3/codec"
+	server "go.unistack.org/micro/v3/server"
 )
 
 type meterServer struct {
@@ -26,8 +28,8 @@ 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

@@ -1,10 +1,11 @@
 // Package meter is for instrumentation
-package meter
+package meter // import "go.unistack.org/micro/v3/meter"
 
 import (
 	"io"
-	"reflect"
 	"sort"
+	"strconv"
+	"strings"
 	"time"
 )
 
@@ -27,17 +28,31 @@ var (
 
 // Meter is an interface for collecting and instrumenting metrics
 type Meter interface {
+	// Name returns meter name
 	Name() string
+	// Init initialize meter
 	Init(opts ...Option) error
+	// Clone create meter copy with new options
+	Clone(opts ...Option) Meter
+	// Counter get or create counter
 	Counter(name string, labels ...string) Counter
+	// FloatCounter get or create float counter
 	FloatCounter(name string, labels ...string) FloatCounter
+	// Gauge get or create gauge
 	Gauge(name string, fn func() float64, labels ...string) Gauge
+	// Set create new meter metrics set
 	Set(opts ...Option) Meter
+	// Histogram get or create histogram
 	Histogram(name string, labels ...string) Histogram
+	// Summary get or create summary
 	Summary(name string, labels ...string) Summary
+	// SummaryExt get or create summary with spcified quantiles and window time
 	SummaryExt(name string, window time.Duration, quantiles []float64, labels ...string) Summary
+	// Write writes metrics to io.Writer
 	Write(w io.Writer, opts ...Option) error
+	// Options returns meter options
 	Options() Options
+	// String return meter type
 	String() string
 }
 
@@ -77,36 +92,62 @@ 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)
+		}
 	}
 }

meter/noop.go

@@ -15,6 +15,15 @@ func NewMeter(opts ...Option) Meter {
 	return &noopMeter{opts: NewOptions(opts...)}
 }
 
+// Clone return old meter with new options
+func (r *noopMeter) Clone(opts ...Option) Meter {
+	options := r.opts
+	for _, o := range opts {
+		o(&options)
+	}
+	return &noopMeter{opts: options}
+}
+
 func (r *noopMeter) Name() string {
 	return r.opts.Name
 }

meter/options.go

@@ -3,7 +3,7 @@ package meter
 import (
 	"context"
 
-	"github.com/unistack-org/micro/v3/logger"
+	"go.unistack.org/micro/v3/logger"
 )
 
 // Option powers the configuration for metrics implementations:
@@ -51,6 +51,20 @@ func NewOptions(opt ...Option) Options {
 	return opts
 }
 
+// LabelPrefix sets the labels prefix
+func LabelPrefix(pref string) Option {
+	return func(o *Options) {
+		o.LabelPrefix = pref
+	}
+}
+
+// MetricPrefix sets the metric prefix
+func MetricPrefix(pref string) Option {
+	return func(o *Options) {
+		o.MetricPrefix = pref
+	}
+}
+
 // Context sets the metrics context
 func Context(ctx context.Context) Option {
 	return func(o *Options) {

meter/wrapper/wrapper.go

@@ -1,13 +1,13 @@
-package wrapper
+package wrapper // import "go.unistack.org/micro/v3/meter/wrapper"
 
 import (
 	"context"
 	"fmt"
 	"time"
 
-	"github.com/unistack-org/micro/v3/client"
-	"github.com/unistack-org/micro/v3/meter"
-	"github.com/unistack-org/micro/v3/server"
+	"go.unistack.org/micro/v3/client"
+	"go.unistack.org/micro/v3/meter"
+	"go.unistack.org/micro/v3/server"
 )
 
 var (

micro.go

@@ -0,0 +1 @@
+package micro // import "go.unistack.org/micro/v3"

model/model.go

@@ -1,35 +0,0 @@
-// +build ignore
-
-// Package model is an interface for data modelling
-package model
-
-// Model provides an interface for data modelling
-type Model interface {
-	// Initialise options
-	Init(...Option) error
-	// NewEntity creates a new entity to store or access
-	NewEntity(name string, value interface{}) Entity
-	// Create a value
-	Create(Entity) error
-	// Read values
-	Read(...ReadOption) ([]Entity, error)
-	// Update the value
-	Update(Entity) error
-	// Delete an entity
-	Delete(...DeleteOption) error
-	// Implementation of the model
-	String() string
-}
-
-type Entity interface {
-	// Unique id of the entity
-	Id() string
-	// Name of the entity
-	Name() string
-	// The value associated with the entity
-	Value() interface{}
-	// Attributes of the entity
-	Attributes() map[string]interface{}
-	// Read a value as a concrete type
-	Read(v interface{}) error
-}

model/options.go

@@ -1,41 +0,0 @@
-// +build ignore
-
-// Package model is an interface for data modelling
-package model
-
-import (
-	"github.com/unistack-org/micro/v3/codec"
-	"github.com/unistack-org/micro/v3/logger"
-	"github.com/unistack-org/micro/v3/store"
-	"github.com/unistack-org/micro/v3/sync"
-)
-
-type Options struct {
-	// Database to write to
-	Database string
-	// for serialising
-	Codec codec.Codec
-	// for locking
-	Sync sync.Sync
-	// for storage
-	Store store.Store
-	// for logger
-	Logger logger.Logger
-}
-
-type Option func(o *Options)
-
-// Logger sets the logger
-func Logger(l logger.Logger) Option {
-	return func(o *Options) {
-		o.Logger = l
-	}
-}
-
-type ReadOptions struct{}
-
-type ReadOption func(o *ReadOptions)
-
-type DeleteOptions struct{}
-
-type DeleteOption func(o *DeleteOptions)

network/network.go

@@ -1,9 +1,9 @@
 // Package network is for creating internetworks
-package network
+package network // import "go.unistack.org/micro/v3/network"
 
 import (
-	"github.com/unistack-org/micro/v3/client"
-	"github.com/unistack-org/micro/v3/server"
+	"go.unistack.org/micro/v3/client"
+	"go.unistack.org/micro/v3/server"
 )
 
 // Error is network node errors

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"
+	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v3/meter"
+	"go.unistack.org/micro/v3/network/tunnel"
+	"go.unistack.org/micro/v3/proxy"
+	"go.unistack.org/micro/v3/router"
+	"go.unistack.org/micro/v3/tracer"
+	"go.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.go

@@ -8,9 +8,9 @@ import (
 	"sync"
 	"time"
 
-	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"
+	maddr "go.unistack.org/micro/v3/util/addr"
+	mnet "go.unistack.org/micro/v3/util/net"
+	"go.unistack.org/micro/v3/util/rand"
 )
 
 type memorySocket struct {

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/transport/options.go

@@ -5,10 +5,10 @@ import (
 	"crypto/tls"
 	"time"
 
-	"github.com/unistack-org/micro/v3/codec"
-	"github.com/unistack-org/micro/v3/logger"
-	"github.com/unistack-org/micro/v3/meter"
-	"github.com/unistack-org/micro/v3/tracer"
+	"go.unistack.org/micro/v3/codec"
+	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v3/meter"
+	"go.unistack.org/micro/v3/tracer"
 )
 
 // Options struct holds the transport options

network/transport/transport.go

@@ -1,11 +1,11 @@
 // Package transport is an interface for synchronous connection based communication
-package transport
+package transport // import "go.unistack.org/micro/v3/network/transport"
 
 import (
 	"context"
 	"time"
 
-	"github.com/unistack-org/micro/v3/metadata"
+	"go.unistack.org/micro/v3/metadata"
 )
 
 var (

network/tunnel/broker/broker.go

@@ -1,14 +1,15 @@
 // Package broker is a tunnel broker
-package broker
+package broker // import "go.unistack.org/micro/v3/network/tunnel/broker"
 
 import (
 	"context"
 	"fmt"
 
-	"github.com/unistack-org/micro/v3/broker"
-	"github.com/unistack-org/micro/v3/logger"
-	"github.com/unistack-org/micro/v3/network/transport"
-	"github.com/unistack-org/micro/v3/network/tunnel"
+	"go.unistack.org/micro/v3/broker"
+	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v3/metadata"
+	"go.unistack.org/micro/v3/network/transport"
+	"go.unistack.org/micro/v3/network/tunnel"
 )
 
 type tunBroker struct {
@@ -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"
+	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v3/meter"
+	"go.unistack.org/micro/v3/network/transport"
+	"go.unistack.org/micro/v3/tracer"
+	"go.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/listener.go

@@ -1,8 +1,8 @@
 package transport
 
 import (
-	"github.com/unistack-org/micro/v3/network/transport"
-	"github.com/unistack-org/micro/v3/network/tunnel"
+	"go.unistack.org/micro/v3/network/transport"
+	"go.unistack.org/micro/v3/network/tunnel"
 )
 
 type tunListener struct {

network/tunnel/transport/transport.go

@@ -1,12 +1,12 @@
 // Package transport provides a tunnel transport
-package transport
+package transport // import "go.unistack.org/micro/v3/network/tunnel/transport"
 
 import (
 	"context"
 	"fmt"
 
-	"github.com/unistack-org/micro/v3/network/transport"
-	"github.com/unistack-org/micro/v3/network/tunnel"
+	"go.unistack.org/micro/v3/network/transport"
+	"go.unistack.org/micro/v3/network/tunnel"
 )
 
 type tunTransport struct {
@@ -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

network/tunnel/tunnel.go

@@ -1,12 +1,12 @@
 // Package tunnel provides gre network tunnelling
-package tunnel
+package tunnel // import "go.unistack.org/micro/v3/network/transport/tunnel"
 
 import (
 	"context"
 	"errors"
 	"time"
 
-	"github.com/unistack-org/micro/v3/network/transport"
+	"go.unistack.org/micro/v3/network/transport"
 )
 
 // DefaultTunnel contains default tunnel implementation

options.go

@@ -5,18 +5,18 @@ import (
 	"fmt"
 	"time"
 
-	"github.com/unistack-org/micro/v3/auth"
-	"github.com/unistack-org/micro/v3/broker"
-	"github.com/unistack-org/micro/v3/client"
-	"github.com/unistack-org/micro/v3/config"
-	"github.com/unistack-org/micro/v3/logger"
-	"github.com/unistack-org/micro/v3/metadata"
-	"github.com/unistack-org/micro/v3/meter"
-	"github.com/unistack-org/micro/v3/register"
-	"github.com/unistack-org/micro/v3/router"
-	"github.com/unistack-org/micro/v3/server"
-	"github.com/unistack-org/micro/v3/store"
-	"github.com/unistack-org/micro/v3/tracer"
+	"go.unistack.org/micro/v3/auth"
+	"go.unistack.org/micro/v3/broker"
+	"go.unistack.org/micro/v3/client"
+	"go.unistack.org/micro/v3/config"
+	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v3/metadata"
+	"go.unistack.org/micro/v3/meter"
+	"go.unistack.org/micro/v3/register"
+	"go.unistack.org/micro/v3/router"
+	"go.unistack.org/micro/v3/server"
+	"go.unistack.org/micro/v3/store"
+	"go.unistack.org/micro/v3/tracer"
 )
 
 // Options for micro service

profiler/http/http.go

@@ -1,5 +1,5 @@
 // Package http enables the http profiler
-package http
+package http // import "go.unistack.org/micro/v3/profiler/http"
 
 import (
 	"context"
@@ -7,7 +7,7 @@ import (
 	"net/http/pprof"
 	"sync"
 
-	profile "github.com/unistack-org/micro/v3/profiler"
+	profile "go.unistack.org/micro/v3/profiler"
 )
 
 type httpProfile struct {

profiler/pprof/pprof.go

@@ -1,5 +1,5 @@
 // Package pprof provides a pprof profiler which writes output to /tmp/[name].{cpu,mem}.pprof
-package pprof
+package pprof // import "go.unistack.org/micro/v3/profiler/pprof"
 
 import (
 	"os"
@@ -9,7 +9,7 @@ import (
 	"sync"
 	"time"
 
-	profile "github.com/unistack-org/micro/v3/profiler"
+	profile "go.unistack.org/micro/v3/profiler"
 )
 
 type profiler struct {
@@ -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
 		}

profiler/profile.go

@@ -1,5 +1,5 @@
 // Package profiler is for profilers
-package profiler
+package profiler // import "go.unistack.org/micro/v3/profiler"
 
 // Profiler interface
 type Profiler interface {

proxy/options.go

@@ -2,11 +2,11 @@
 package proxy
 
 import (
-	"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/router"
-	"github.com/unistack-org/micro/v3/tracer"
+	"go.unistack.org/micro/v3/client"
+	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v3/meter"
+	"go.unistack.org/micro/v3/router"
+	"go.unistack.org/micro/v3/tracer"
 )
 
 // Options for proxy

proxy/proxy.go

@@ -1,10 +1,10 @@
 // Package proxy is a transparent proxy built on the micro/server
-package proxy
+package proxy // import "go.unistack.org/micro/v3/proxy"
 
 import (
 	"context"
 
-	"github.com/unistack-org/micro/v3/server"
+	"go.unistack.org/micro/v3/server"
 )
 
 // DefaultEndpoint holds default proxy address

register/extractor.go

@@ -6,7 +6,7 @@ import (
 	"unicode"
 	"unicode/utf8"
 
-	"github.com/unistack-org/micro/v3/metadata"
+	"go.unistack.org/micro/v3/metadata"
 )
 
 // ExtractValue from reflect.Type from specified depth

register/memory.go

@@ -6,8 +6,8 @@ import (
 	"sync"
 	"time"
 
-	"github.com/google/uuid"
-	"github.com/unistack-org/micro/v3/logger"
+	"go.unistack.org/micro/v3/logger"
+	"go.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

@@ -5,9 +5,9 @@ import (
 	"crypto/tls"
 	"time"
 
-	"github.com/unistack-org/micro/v3/logger"
-	"github.com/unistack-org/micro/v3/meter"
-	"github.com/unistack-org/micro/v3/tracer"
+	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v3/meter"
+	"go.unistack.org/micro/v3/tracer"
 )
 
 // Options holds options for register
@@ -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

@@ -1,11 +1,11 @@
 // Package register is an interface for service discovery
-package register
+package register // import "go.unistack.org/micro/v3/register"
 
 import (
 	"context"
 	"errors"
 
-	"github.com/unistack-org/micro/v3/metadata"
+	"go.unistack.org/micro/v3/metadata"
 )
 
 const (
@@ -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