meter: improve meter usage across micro framework (#409)

Reviewed-on: #409
Co-authored-by: Vasiliy Tolstov <v.tolstov@unistack.org>
Co-committed-by: Vasiliy Tolstov <v.tolstov@unistack.org>

.github/workflows/job_sync.yml

@@ -0,0 +1,94 @@
+name: sync
+
+on:
+  schedule:
+    - cron: '*/5 * * * *'
+  # Allows you to run this workflow manually from the Actions tab
+  workflow_dispatch:
+
+jobs:
+  sync:
+    if: github.server_url != 'https://github.com'
+    runs-on: ubuntu-latest
+    steps:
+    - name: init
+      run: |
+        git config --global user.email "vtolstov <vtolstov@users.noreply.github.com>"
+        git config --global user.name "github-actions[bot]"
+        echo "machine git.unistack.org login vtolstov password ${{ secrets.TOKEN_GITEA }}" >> /root/.netrc
+        echo "machine github.com login vtolstov password ${{ secrets.TOKEN_GITHUB }}" >> /root/.netrc
+
+    - name: check master
+      id: check_master
+      run: |
+        src_hash=$(git ls-remote https://github.com/${GITHUB_REPOSITORY} refs/heads/master | cut -f1)
+        dst_hash=$(git ls-remote ${GITHUB_SERVER_URL}/${GITHUB_REPOSITORY} refs/heads/master | cut -f1)
+        echo "src_hash=$src_hash"
+        echo "dst_hash=$dst_hash"
+        if [ "$src_hash" != "$dst_hash" ]; then
+          echo "sync_needed=true" >> $GITHUB_OUTPUT
+        else
+          echo "sync_needed=false" >> $GITHUB_OUTPUT
+        fi
+
+    - name: sync master
+      if: steps.check_master.outputs.sync_needed == 'true'
+      run: |
+        git clone --filter=blob:none --filter=tree:0 --branch master --single-branch ${GITHUB_SERVER_URL}/${GITHUB_REPOSITORY} repo
+        cd repo
+        git remote add --no-tags --fetch --track master upstream https://github.com/${GITHUB_REPOSITORY}
+        git pull --rebase upstream master
+        git push upstream master --progress
+        git push origin master --progress
+        cd ../
+        rm -rf repo
+
+    - name: check v3
+      id: check_v3
+      run: |
+        src_hash=$(git ls-remote https://github.com/${GITHUB_REPOSITORY} refs/heads/v3 | cut -f1)
+        dst_hash=$(git ls-remote ${GITHUB_SERVER_URL}/${GITHUB_REPOSITORY} refs/heads/v3 | cut -f1)
+        echo "src_hash=$src_hash"
+        echo "dst_hash=$dst_hash"
+        if [ "$src_hash" != "$dst_hash" ]; then
+          echo "sync_needed=true" >> $GITHUB_OUTPUT
+        else
+          echo "sync_needed=false" >> $GITHUB_OUTPUT
+        fi
+
+    - name: sync v3
+      if: steps.check_v3.outputs.sync_needed == 'true'
+      run: |
+        git clone --filter=blob:none --filter=tree:0 --branch v3 --single-branch ${GITHUB_SERVER_URL}/${GITHUB_REPOSITORY} repo
+        cd repo
+        git remote add --no-tags --fetch --track v3 upstream https://github.com/${GITHUB_REPOSITORY}
+        git pull --rebase upstream v3
+        git push upstream v3 --progress
+        git push origin v3 --progress
+        cd ../
+        rm -rf repo
+
+    - name: check v4
+      id: check_v4
+      run: |
+        src_hash=$(git ls-remote https://github.com/${GITHUB_REPOSITORY} refs/heads/v4 | cut -f1)
+        dst_hash=$(git ls-remote ${GITHUB_SERVER_URL}/${GITHUB_REPOSITORY} refs/heads/v4 | cut -f1)
+        echo "src_hash=$src_hash"
+        echo "dst_hash=$dst_hash"
+        if [ "$src_hash" != "$dst_hash" ]; then
+          echo "sync_needed=true" >> $GITHUB_OUTPUT
+        else
+          echo "sync_needed=false" >> $GITHUB_OUTPUT
+        fi
+
+    - name: sync v4
+      if: steps.check_v4.outputs.sync_needed == 'true'
+      run: |
+        git clone --filter=blob:none --filter=tree:0 --branch v4 --single-branch ${GITHUB_SERVER_URL}/${GITHUB_REPOSITORY} repo
+        cd repo
+        git remote add --no-tags --fetch --track v4 upstream https://github.com/${GITHUB_REPOSITORY}
+        git pull --rebase upstream v4
+        git push upstream v4 --progress
+        git push origin v4 --progress
+        cd ../
+        rm -rf repo

README.md

@@ -1,28 +1,28 @@
 # Micro
 ![Coverage](https://img.shields.io/badge/Coverage-34.1%25-yellow)
 [![License](https://img.shields.io/:license-apache-blue.svg)](https://opensource.org/licenses/Apache-2.0)
-[![Doc](https://img.shields.io/badge/go.dev-reference-007d9c?logo=go&logoColor=white&style=flat-square)](https://pkg.go.dev/go.unistack.org/micro/v3?tab=overview)
-[![Status](https://git.unistack.org/unistack-org/micro/actions/workflows/job_tests.yml/badge.svg?branch=v3)](https://git.unistack.org/unistack-org/micro/actions?query=workflow%3Abuild+branch%3Av3+event%3Apush)
-[![Lint](https://goreportcard.com/badge/go.unistack.org/micro/v3)](https://goreportcard.com/report/go.unistack.org/micro/v3)
+[![Doc](https://img.shields.io/badge/go.dev-reference-007d9c?logo=go&logoColor=white&style=flat-square)](https://pkg.go.dev/go.unistack.org/micro/v4?tab=overview)
+[![Status](https://git.unistack.org/unistack-org/micro/actions/workflows/job_tests.yml/badge.svg?branch=v4)](https://git.unistack.org/unistack-org/micro/actions?query=workflow%3Abuild+branch%3Av4+event%3Apush)
+[![Lint](https://goreportcard.com/badge/go.unistack.org/micro/v4)](https://goreportcard.com/report/go.unistack.org/micro/v4)
 
 Micro is a standard library for microservices.
 
 ## Overview
 
-Micro provides the core requirements for distributed systems development including SYNC and ASYNC communication. 
+Micro provides the core requirements for distributed systems development including RPC and Event driven communication. 
 
 ## Features
 
-Micro abstracts away the details of distributed systems. Main features:
+Micro abstracts away the details of distributed systems. Here are the main features.
 
 - **Dynamic Config** - Load and hot reload dynamic config from anywhere. The config interface provides a way to load application 
-level config from any source such as env vars, cmdline, file, consul, vault, etc... You can merge the sources and even define fallbacks.
+level config from any source such as env vars, cmdline, file, consul, vault... You can merge the sources and even define fallbacks.
 
 - **Data Storage** - A simple data store interface to read, write and delete records. It includes support for memory, file and 
 s3. State and persistence becomes a core requirement beyond prototyping and Micro looks to build that into the framework.
 
 - **Service Discovery** - Automatic service registration and name resolution. Service discovery is at the core of micro service 
-development.
+development. When service A needs to speak to service B it needs the location of that service.
 
 - **Message Encoding** - Dynamic message encoding based on content-type. The client and server will use codecs along with content-type 
 to seamlessly encode and decode Go types for you. Any variety of messages could be encoded and sent from different clients. The client 

broker/broker.go

@@ -6,8 +6,8 @@ import (
 	"errors"
 	"time"
 
-	"go.unistack.org/micro/v3/codec"
-	"go.unistack.org/micro/v3/metadata"
+	"go.unistack.org/micro/v4/codec"
+	"go.unistack.org/micro/v4/metadata"
 )
 
 // DefaultBroker default memory broker
@@ -18,6 +18,10 @@ var (
 	ErrNotConnected = errors.New("broker not connected")
 	// ErrDisconnected returns when broker disconnected
 	ErrDisconnected = errors.New("broker disconnected")
+	// ErrInvalidMessage returns when invalid Message passed
+	ErrInvalidMessage = errors.New("invalid message")
+	// ErrInvalidHandler returns when subscriber passed to Subscribe
+	ErrInvalidHandler = errors.New("invalid handler, ony func(Message) error and func([]Message) error supported")
 	// DefaultGracefulTimeout
 	DefaultGracefulTimeout = 5 * time.Second
 )
@@ -36,14 +40,12 @@ type Broker interface {
 	Connect(ctx context.Context) error
 	// Disconnect disconnect from broker
 	Disconnect(ctx context.Context) error
+	// NewMessage create new broker message to publish.
+	NewMessage(ctx context.Context, hdr metadata.Metadata, body interface{}, opts ...MessageOption) (Message, error)
 	// Publish message to broker topic
-	Publish(ctx context.Context, topic string, msg *Message, opts ...PublishOption) error
+	Publish(ctx context.Context, topic string, messages ...Message) 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)
+	Subscribe(ctx context.Context, topic string, handler interface{}, opts ...SubscribeOption) (Subscriber, error)
 	// String type of broker
 	String() string
 	// Live returns broker liveness
@@ -55,72 +57,27 @@ type Broker interface {
 }
 
 type (
-	FuncPublish        func(ctx context.Context, topic string, msg *Message, opts ...PublishOption) error
-	HookPublish        func(next FuncPublish) FuncPublish
-	FuncBatchPublish   func(ctx context.Context, msgs []*Message, opts ...PublishOption) error
-	HookBatchPublish   func(next FuncBatchPublish) FuncBatchPublish
-	FuncSubscribe      func(ctx context.Context, topic string, h Handler, opts ...SubscribeOption) (Subscriber, error)
-	HookSubscribe      func(next FuncSubscribe) FuncSubscribe
-	FuncBatchSubscribe func(ctx context.Context, topic string, h BatchHandler, opts ...SubscribeOption) (Subscriber, error)
-	HookBatchSubscribe func(next FuncBatchSubscribe) FuncBatchSubscribe
+	FuncPublish   func(ctx context.Context, topic string, messages ...Message) error
+	HookPublish   func(next FuncPublish) FuncPublish
+	FuncSubscribe func(ctx context.Context, topic string, handler interface{}, opts ...SubscribeOption) (Subscriber, error)
+	HookSubscribe func(next FuncSubscribe) FuncSubscribe
 )
 
-// Handler is used to process messages via a subscription of a topic.
-type Handler func(Event) error
-
-// Events contains multiple events
-type Events []Event
-
-// Ack try to ack all events and return
-func (evs Events) Ack() error {
-	var err error
-	for _, ev := range evs {
-		if err = ev.Ack(); err != nil {
-			return err
-		}
-	}
-	return nil
-}
-
-// SetError sets error on event
-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 {
-	// Context return context.Context for event
+// Message is given to a subscription handler for processing
+type Message interface {
+	// Context for the message.
 	Context() context.Context
-	// Topic returns event topic
+	// Topic returns message destination topic.
 	Topic() string
-	// Message returns broker message
-	Message() *Message
-	// Ack acknowledge message
+	// Header returns message headers.
+	Header() metadata.Metadata
+	// Body returns broker message []byte slice
+	Body() []byte
+	// Unmarshal try to decode message body to dst.
+	// This is helper method that uses codec.Unmarshal.
+	Unmarshal(dst interface{}, opts ...codec.Option) error
+	// Ack acknowledge message if supported.
 	Ack() error
-	// Error returns message error (like decoding errors or some other)
-	Error() error
-	// SetError set event processing error
-	SetError(err error)
-}
-
-// Message is used to transfer data
-type Message struct {
-	// Header contains message metadata
-	Header metadata.Metadata
-	// Body contains message body
-	Body codec.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

broker/context.go

@@ -42,6 +42,16 @@ func SetSubscribeOption(k, v interface{}) SubscribeOption {
 	}
 }
 
+// SetMessageOption returns a function to setup a context with given value
+func SetMessageOption(k, v interface{}) MessageOption {
+	return func(o *MessageOptions) {
+		if o.Context == nil {
+			o.Context = context.Background()
+		}
+		o.Context = context.WithValue(o.Context, k, v)
+	}
+}
+
 // SetOption returns a function to setup a context with given value
 func SetOption(k, v interface{}) Option {
 	return func(o *Options) {
@@ -51,13 +61,3 @@ func SetOption(k, v interface{}) Option {
 		o.Context = context.WithValue(o.Context, k, v)
 	}
 }
-
-// SetPublishOption returns a function to setup a context with given value
-func SetPublishOption(k, v interface{}) PublishOption {
-	return func(o *PublishOptions) {
-		if o.Context == nil {
-			o.Context = context.Background()
-		}
-		o.Context = context.WithValue(o.Context, k, v)
-	}
-}

broker/context_test.go

@@ -49,17 +49,6 @@ func TestSetSubscribeOption(t *testing.T) {
 	}
 }
 
-func TestSetPublishOption(t *testing.T) {
-	type key struct{}
-	o := SetPublishOption(key{}, "test")
-	opts := &PublishOptions{}
-	o(opts)
-
-	if v, ok := opts.Context.Value(key{}).(string); !ok || v == "" {
-		t.Fatal("SetPublishOption not works")
-	}
-}
-
 func TestSetOption(t *testing.T) {
 	type key struct{}
 	o := SetOption(key{}, "test")

broker/memory/memory.go

@@ -2,66 +2,104 @@ package broker
 
 import (
 	"context"
+	"strings"
 	"sync"
 
-	"go.unistack.org/micro/v3/broker"
-	"go.unistack.org/micro/v3/logger"
-	"go.unistack.org/micro/v3/metadata"
-	"go.unistack.org/micro/v3/options"
-	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"
+	"go.unistack.org/micro/v4/broker"
+	"go.unistack.org/micro/v4/codec"
+	"go.unistack.org/micro/v4/logger"
+	"go.unistack.org/micro/v4/metadata"
+	"go.unistack.org/micro/v4/options"
+	maddr "go.unistack.org/micro/v4/util/addr"
+	"go.unistack.org/micro/v4/util/id"
+	mnet "go.unistack.org/micro/v4/util/net"
+	"go.unistack.org/micro/v4/util/rand"
 )
 
-type memoryBroker struct {
-	funcPublish        broker.FuncPublish
-	funcBatchPublish   broker.FuncBatchPublish
-	funcSubscribe      broker.FuncSubscribe
-	funcBatchSubscribe broker.FuncBatchSubscribe
-	subscribers        map[string][]*memorySubscriber
-	addr               string
-	opts               broker.Options
-	sync.RWMutex
-	connected bool
+type Broker struct {
+	funcPublish   broker.FuncPublish
+	funcSubscribe broker.FuncSubscribe
+	subscribers   map[string][]*Subscriber
+	addr          string
+	opts          broker.Options
+	mu            sync.RWMutex
+	connected     bool
 }
 
-type memoryEvent struct {
-	err     error
-	message interface{}
+type memoryMessage struct {
+	c     codec.Codec
+	topic string
+	ctx   context.Context
+	body  []byte
+	hdr   metadata.Metadata
+	opts  broker.MessageOptions
+}
+
+func (m *memoryMessage) Ack() error {
+	return nil
+}
+
+func (m *memoryMessage) Body() []byte {
+	return m.body
+}
+
+func (m *memoryMessage) Header() metadata.Metadata {
+	return m.hdr
+}
+
+func (m *memoryMessage) Context() context.Context {
+	return m.ctx
+}
+
+func (m *memoryMessage) Topic() string {
+	return ""
+}
+
+func (m *memoryMessage) Unmarshal(dst interface{}, opts ...codec.Option) error {
+	return m.c.Unmarshal(m.body, dst)
+}
+
+type Subscriber struct {
+	ctx     context.Context
+	exit    chan bool
+	handler interface{}
+	id      string
 	topic   string
-	opts    broker.Options
+	opts    broker.SubscribeOptions
 }
 
-type memorySubscriber struct {
-	ctx          context.Context
-	exit         chan bool
-	handler      broker.Handler
-	batchhandler broker.BatchHandler
-	id           string
-	topic        string
-	opts         broker.SubscribeOptions
+func (b *Broker) newCodec(ct string) (codec.Codec, error) {
+	if idx := strings.IndexRune(ct, ';'); idx >= 0 {
+		ct = ct[:idx]
+	}
+	b.mu.RLock()
+	c, ok := b.opts.Codecs[ct]
+	b.mu.RUnlock()
+	if ok {
+		return c, nil
+	}
+	return nil, codec.ErrUnknownContentType
 }
 
-func (m *memoryBroker) Options() broker.Options {
-	return m.opts
+func (b *Broker) Options() broker.Options {
+	return b.opts
 }
 
-func (m *memoryBroker) Address() string {
-	return m.addr
+func (b *Broker) Address() string {
+	return b.addr
 }
 
-func (m *memoryBroker) Connect(ctx context.Context) error {
+func (b *Broker) Connect(ctx context.Context) error {
 	select {
 	case <-ctx.Done():
 		return ctx.Err()
 	default:
 	}
 
-	m.Lock()
-	defer m.Unlock()
+	b.mu.Lock()
+	defer b.mu.Unlock()
 
-	if m.connected {
+	if b.connected {
 		return nil
 	}
 
@@ -75,154 +113,129 @@ func (m *memoryBroker) Connect(ctx context.Context) error {
 	// set addr with port
 	addr = mnet.HostPort(addr, 10000+i)
 
-	m.addr = addr
-	m.connected = true
+	b.addr = addr
+	b.connected = true
 
 	return nil
 }
 
-func (m *memoryBroker) Disconnect(ctx context.Context) error {
+func (b *Broker) Disconnect(ctx context.Context) error {
 	select {
 	case <-ctx.Done():
 		return ctx.Err()
 	default:
 	}
 
-	m.Lock()
-	defer m.Unlock()
+	b.mu.Lock()
+	defer b.mu.Unlock()
 
-	if !m.connected {
+	if !b.connected {
 		return nil
 	}
 
-	m.connected = false
+	b.connected = false
 	return nil
 }
 
-func (m *memoryBroker) Init(opts ...broker.Option) error {
+func (b *Broker) Init(opts ...broker.Option) error {
 	for _, o := range opts {
-		o(&m.opts)
+		o(&b.opts)
 	}
 
-	m.funcPublish = m.fnPublish
-	m.funcBatchPublish = m.fnBatchPublish
-	m.funcSubscribe = m.fnSubscribe
-	m.funcBatchSubscribe = m.fnBatchSubscribe
+	b.funcPublish = b.fnPublish
+	b.funcSubscribe = b.fnSubscribe
 
-	m.opts.Hooks.EachPrev(func(hook options.Hook) {
+	b.opts.Hooks.EachPrev(func(hook options.Hook) {
 		switch h := hook.(type) {
 		case broker.HookPublish:
-			m.funcPublish = h(m.funcPublish)
-		case broker.HookBatchPublish:
-			m.funcBatchPublish = h(m.funcBatchPublish)
+			b.funcPublish = h(b.funcPublish)
 		case broker.HookSubscribe:
-			m.funcSubscribe = h(m.funcSubscribe)
-		case broker.HookBatchSubscribe:
-			m.funcBatchSubscribe = h(m.funcBatchSubscribe)
+			b.funcSubscribe = h(b.funcSubscribe)
 		}
 	})
 
 	return nil
 }
 
-func (m *memoryBroker) Publish(ctx context.Context, topic string, msg *broker.Message, opts ...broker.PublishOption) error {
-	return m.funcPublish(ctx, topic, msg, opts...)
+func (b *Broker) NewMessage(ctx context.Context, hdr metadata.Metadata, body interface{}, opts ...broker.MessageOption) (broker.Message, error) {
+	options := broker.NewMessageOptions(opts...)
+	if options.ContentType == "" {
+		options.ContentType = b.opts.ContentType
+	}
+	m := &memoryMessage{ctx: ctx, hdr: hdr, opts: options}
+	c, err := b.newCodec(m.opts.ContentType)
+	if err == nil {
+		m.body, err = c.Marshal(body)
+	}
+	if err != nil {
+		return nil, err
+	}
+
+	return m, nil
 }
 
-func (m *memoryBroker) fnPublish(ctx context.Context, topic string, msg *broker.Message, opts ...broker.PublishOption) error {
-	msg.Header.Set(metadata.HeaderTopic, topic)
-	return m.publish(ctx, []*broker.Message{msg}, opts...)
+func (b *Broker) Publish(ctx context.Context, topic string, messages ...broker.Message) error {
+	return b.funcPublish(ctx, topic, messages...)
 }
 
-func (m *memoryBroker) BatchPublish(ctx context.Context, msgs []*broker.Message, opts ...broker.PublishOption) error {
-	return m.funcBatchPublish(ctx, msgs, opts...)
+func (b *Broker) fnPublish(ctx context.Context, topic string, messages ...broker.Message) error {
+	return b.publish(ctx, topic, messages...)
 }
 
-func (m *memoryBroker) fnBatchPublish(ctx context.Context, msgs []*broker.Message, opts ...broker.PublishOption) error {
-	return m.publish(ctx, msgs, opts...)
-}
-
-func (m *memoryBroker) publish(ctx context.Context, msgs []*broker.Message, opts ...broker.PublishOption) error {
-	m.RLock()
-	if !m.connected {
-		m.RUnlock()
+func (b *Broker) publish(ctx context.Context, topic string, messages ...broker.Message) error {
+	b.mu.RLock()
+	if !b.connected {
+		b.mu.RUnlock()
 		return broker.ErrNotConnected
 	}
-	m.RUnlock()
-
-	var err error
+	b.mu.RUnlock()
 
 	select {
 	case <-ctx.Done():
 		return ctx.Err()
 	default:
-		options := broker.NewPublishOptions(opts...)
+	}
 
-		msgTopicMap := make(map[string]broker.Events)
-		for _, v := range msgs {
-			p := &memoryEvent{opts: m.opts}
+	b.mu.RLock()
+	subs, ok := b.subscribers[topic]
+	b.mu.RUnlock()
+	if !ok {
+		return nil
+	}
 
-			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
-				}
+	var err error
+
+	for _, sub := range subs {
+		switch s := sub.handler.(type) {
+		default:
+			if b.opts.Logger.V(logger.ErrorLevel) {
+				b.opts.Logger.Error(ctx, "broker  handler error", broker.ErrInvalidHandler)
 			}
-			msgTopicMap[p.topic] = append(msgTopicMap[p.topic], p)
-		}
-
-		beh := m.opts.BatchErrorHandler
-		eh := m.opts.ErrorHandler
-
-		for t, ms := range msgTopicMap {
-			m.RLock()
-			subs, ok := m.subscribers[t]
-			m.RUnlock()
-			if !ok {
-				continue
-			}
-
-			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.Error(m.opts.Context, "broker ack error", err)
-						}
+		case func(broker.Message) error:
+			for _, message := range messages {
+				msg, ok := message.(*memoryMessage)
+				if !ok {
+					if b.opts.Logger.V(logger.ErrorLevel) {
+						b.opts.Logger.Error(ctx, "broker handler error", broker.ErrInvalidMessage)
 					}
-					// 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, "broker handler error", err)
-							}
-						} else if sub.opts.AutoAck {
-							if err = p.Ack(); err != nil {
-								m.opts.Logger.Error(m.opts.Context, "broker ack error", err)
-							}
+				}
+				msg.topic = topic
+				if err = s(msg); err == nil && sub.opts.AutoAck {
+					err = msg.Ack()
+				}
+				if err != nil {
+					if b.opts.Logger.V(logger.ErrorLevel) {
+						b.opts.Logger.Error(ctx, "broker handler error", err)
+					}
+				}
+			}
+		case func([]broker.Message) error:
+			if err = s(messages); err == nil && sub.opts.AutoAck {
+				for _, message := range messages {
+					err = message.Ack()
+					if err != nil {
+						if b.opts.Logger.V(logger.ErrorLevel) {
+							b.opts.Logger.Error(ctx, "broker handler error", err)
 						}
 					}
 				}
@@ -233,17 +246,21 @@ func (m *memoryBroker) publish(ctx context.Context, msgs []*broker.Message, opts
 	return nil
 }
 
-func (m *memoryBroker) BatchSubscribe(ctx context.Context, topic string, handler broker.BatchHandler, opts ...broker.SubscribeOption) (broker.Subscriber, error) {
-	return m.funcBatchSubscribe(ctx, topic, handler, opts...)
+func (b *Broker) Subscribe(ctx context.Context, topic string, handler interface{}, opts ...broker.SubscribeOption) (broker.Subscriber, error) {
+	return b.funcSubscribe(ctx, topic, handler, opts...)
 }
 
-func (m *memoryBroker) fnBatchSubscribe(ctx context.Context, topic string, handler broker.BatchHandler, opts ...broker.SubscribeOption) (broker.Subscriber, error) {
-	m.RLock()
-	if !m.connected {
-		m.RUnlock()
+func (b *Broker) fnSubscribe(ctx context.Context, topic string, handler interface{}, opts ...broker.SubscribeOption) (broker.Subscriber, error) {
+	if err := broker.IsValidHandler(handler); err != nil {
+		return nil, err
+	}
+
+	b.mu.RLock()
+	if !b.connected {
+		b.mu.RUnlock()
 		return nil, broker.ErrNotConnected
 	}
-	m.RUnlock()
+	b.mu.RUnlock()
 
 	sid, err := id.New()
 	if err != nil {
@@ -252,56 +269,7 @@ func (m *memoryBroker) fnBatchSubscribe(ctx context.Context, topic string, handl
 
 	options := broker.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 broker.Handler, opts ...broker.SubscribeOption) (broker.Subscriber, error) {
-	return m.funcSubscribe(ctx, topic, handler, opts...)
-}
-
-func (m *memoryBroker) fnSubscribe(ctx context.Context, topic string, handler broker.Handler, opts ...broker.SubscribeOption) (broker.Subscriber, error) {
-	m.RLock()
-	if !m.connected {
-		m.RUnlock()
-		return nil, broker.ErrNotConnected
-	}
-	m.RUnlock()
-
-	sid, err := id.New()
-	if err != nil {
-		return nil, err
-	}
-
-	options := broker.NewSubscribeOptions(opts...)
-
-	sub := &memorySubscriber{
+	sub := &Subscriber{
 		exit:    make(chan bool, 1),
 		id:      sid,
 		topic:   topic,
@@ -310,102 +278,64 @@ func (m *memoryBroker) fnSubscribe(ctx context.Context, topic string, handler br
 		ctx:     ctx,
 	}
 
-	m.Lock()
-	m.subscribers[topic] = append(m.subscribers[topic], sub)
-	m.Unlock()
+	b.mu.Lock()
+	b.subscribers[topic] = append(b.subscribers[topic], sub)
+	b.mu.Unlock()
 
 	go func() {
 		<-sub.exit
-		m.Lock()
-		newSubscribers := make([]*memorySubscriber, 0, len(m.subscribers)-1)
-		for _, sb := range m.subscribers[topic] {
+		b.mu.Lock()
+		newSubscribers := make([]*Subscriber, 0, len(b.subscribers)-1)
+		for _, sb := range b.subscribers[topic] {
 			if sb.id == sub.id {
 				continue
 			}
 			newSubscribers = append(newSubscribers, sb)
 		}
-		m.subscribers[topic] = newSubscribers
-		m.Unlock()
+		b.subscribers[topic] = newSubscribers
+		b.mu.Unlock()
 	}()
 
 	return sub, nil
 }
 
-func (m *memoryBroker) String() string {
+func (b *Broker) String() string {
 	return "memory"
 }
 
-func (m *memoryBroker) Name() string {
-	return m.opts.Name
+func (b *Broker) Name() string {
+	return b.opts.Name
 }
 
-func (m *memoryBroker) Live() bool {
+func (b *Broker) Live() bool {
 	return true
 }
 
-func (m *memoryBroker) Ready() bool {
+func (b *Broker) Ready() bool {
 	return true
 }
 
-func (m *memoryBroker) Health() bool {
+func (b *Broker) Health() bool {
 	return true
 }
 
-func (m *memoryEvent) Topic() string {
-	return m.topic
-}
-
-func (m *memoryEvent) Message() *broker.Message {
-	switch v := m.message.(type) {
-	case *broker.Message:
-		return v
-	case []byte:
-		msg := &broker.Message{}
-		if err := m.opts.Codec.Unmarshal(v, msg); err != nil {
-			if m.opts.Logger.V(logger.ErrorLevel) {
-				m.opts.Logger.Error(m.opts.Context, "[memory]: failed to unmarshal: %v", err)
-			}
-			return nil
-		}
-		return msg
-	}
-
-	return nil
-}
-
-func (m *memoryEvent) Ack() error {
-	return nil
-}
-
-func (m *memoryEvent) Error() error {
-	return m.err
-}
-
-func (m *memoryEvent) SetError(err error) {
-	m.err = err
-}
-
-func (m *memoryEvent) Context() context.Context {
-	return m.opts.Context
-}
-
-func (m *memorySubscriber) Options() broker.SubscribeOptions {
+func (m *Subscriber) Options() broker.SubscribeOptions {
 	return m.opts
 }
 
-func (m *memorySubscriber) Topic() string {
+func (m *Subscriber) Topic() string {
 	return m.topic
 }
 
-func (m *memorySubscriber) Unsubscribe(ctx context.Context) error {
+func (m *Subscriber) Unsubscribe(ctx context.Context) error {
 	m.exit <- true
 	return nil
 }
 
 // NewBroker return new memory broker
 func NewBroker(opts ...broker.Option) broker.Broker {
-	return &memoryBroker{
+	return &Broker{
 		opts:        broker.NewOptions(opts...),
-		subscribers: make(map[string][]*memorySubscriber),
+		subscribers: make(map[string][]*Subscriber),
 	}
 }

broker/memory/memory_test.go

@@ -5,62 +5,23 @@ import (
 	"fmt"
 	"testing"
 
-	"go.unistack.org/micro/v3/broker"
-	"go.unistack.org/micro/v3/metadata"
+	"go.uber.org/atomic"
+	"go.unistack.org/micro/v4/broker"
+	"go.unistack.org/micro/v4/codec"
+	"go.unistack.org/micro/v4/metadata"
 )
 
-func TestMemoryBatchBroker(t *testing.T) {
-	b := NewBroker()
-	ctx := context.Background()
+type hldr struct {
+	c atomic.Int64
+}
 
-	if err := b.Init(); err != nil {
-		t.Fatalf("Unexpected init error %v", err)
-	}
-
-	if err := b.Connect(ctx); err != nil {
-		t.Fatalf("Unexpected connect error %v", err)
-	}
-
-	topic := "test"
-	count := 10
-
-	fn := func(evts broker.Events) error {
-		return evts.Ack()
-	}
-
-	sub, err := b.BatchSubscribe(ctx, topic, fn)
-	if err != nil {
-		t.Fatalf("Unexpected error subscribing %v", err)
-	}
-
-	msgs := make([]*broker.Message, 0, count)
-	for i := 0; i < count; i++ {
-		message := &broker.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 (h *hldr) Handler(m broker.Message) error {
+	h.c.Add(1)
+	return nil
 }
 
 func TestMemoryBroker(t *testing.T) {
-	b := NewBroker()
+	b := NewBroker(broker.Codec("application/octet-stream", codec.NewCodec()))
 	ctx := context.Background()
 
 	if err := b.Init(); err != nil {
@@ -72,38 +33,33 @@ func TestMemoryBroker(t *testing.T) {
 	}
 
 	topic := "test"
-	count := 10
+	count := int64(10)
 
-	fn := func(_ broker.Event) error {
-		return nil
-	}
+	h := &hldr{}
 
-	sub, err := b.Subscribe(ctx, topic, fn)
+	sub, err := b.Subscribe(ctx, topic, h.Handler)
 	if err != nil {
 		t.Fatalf("Unexpected error subscribing %v", err)
 	}
 
-	msgs := make([]*broker.Message, 0, count)
-	for i := 0; i < count; i++ {
-		message := &broker.Message{
-			Header: map[string]string{
-				metadata.HeaderTopic: topic,
-				"foo":                "bar",
-				"id":                 fmt.Sprintf("%d", i),
-			},
-			Body: []byte(`"hello world"`),
+	for i := int64(0); i < count; i++ {
+		message, err := b.NewMessage(ctx,
+			metadata.Pairs(
+				"foo", "bar",
+				"id", fmt.Sprintf("%d", i),
+			),
+			[]byte(`"hello world"`),
+			broker.MessageContentType("application/octet-stream"),
+		)
+		if err != nil {
+			t.Fatal(err)
 		}
-		msgs = append(msgs, message)
 
 		if err := b.Publish(ctx, topic, message); err != nil {
 			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)
 	}
@@ -111,4 +67,8 @@ func TestMemoryBroker(t *testing.T) {
 	if err := b.Disconnect(ctx); err != nil {
 		t.Fatalf("Unexpected connect error %v", err)
 	}
+
+	if h.c.Load() != count {
+		t.Fatal("invalid messages count received")
+	}
 }

broker/noop.go

@@ -3,24 +3,37 @@ package broker
 import (
 	"context"
 	"strings"
+	"sync"
 
-	"go.unistack.org/micro/v3/options"
+	"go.unistack.org/micro/v4/codec"
+	"go.unistack.org/micro/v4/metadata"
+	"go.unistack.org/micro/v4/options"
 )
 
 type NoopBroker struct {
-	funcPublish        FuncPublish
-	funcBatchPublish   FuncBatchPublish
-	funcSubscribe      FuncSubscribe
-	funcBatchSubscribe FuncBatchSubscribe
-	opts               Options
+	funcPublish   FuncPublish
+	funcSubscribe FuncSubscribe
+	opts          Options
+	mu            sync.RWMutex
+}
+
+func (b *NoopBroker) newCodec(ct string) (codec.Codec, error) {
+	if idx := strings.IndexRune(ct, ';'); idx >= 0 {
+		ct = ct[:idx]
+	}
+	b.mu.RLock()
+	c, ok := b.opts.Codecs[ct]
+	b.mu.RUnlock()
+	if ok {
+		return c, nil
+	}
+	return nil, codec.ErrUnknownContentType
 }
 
 func NewBroker(opts ...Option) *NoopBroker {
 	b := &NoopBroker{opts: NewOptions(opts...)}
 	b.funcPublish = b.fnPublish
-	b.funcBatchPublish = b.fnBatchPublish
 	b.funcSubscribe = b.fnSubscribe
-	b.funcBatchSubscribe = b.fnBatchSubscribe
 
 	return b
 }
@@ -55,20 +68,14 @@ func (b *NoopBroker) Init(opts ...Option) error {
 	}
 
 	b.funcPublish = b.fnPublish
-	b.funcBatchPublish = b.fnBatchPublish
 	b.funcSubscribe = b.fnSubscribe
-	b.funcBatchSubscribe = b.fnBatchSubscribe
 
 	b.opts.Hooks.EachPrev(func(hook options.Hook) {
 		switch h := hook.(type) {
 		case HookPublish:
 			b.funcPublish = h(b.funcPublish)
-		case HookBatchPublish:
-			b.funcBatchPublish = h(b.funcBatchPublish)
 		case HookSubscribe:
 			b.funcSubscribe = h(b.funcSubscribe)
-		case HookBatchSubscribe:
-			b.funcBatchSubscribe = h(b.funcBatchSubscribe)
 		}
 	})
 
@@ -87,43 +94,75 @@ func (b *NoopBroker) Address() string {
 	return strings.Join(b.opts.Addrs, ",")
 }
 
-func (b *NoopBroker) fnBatchPublish(_ context.Context, _ []*Message, _ ...PublishOption) error {
+type noopMessage struct {
+	c    codec.Codec
+	ctx  context.Context
+	body []byte
+	hdr  metadata.Metadata
+	opts MessageOptions
+}
+
+func (m *noopMessage) Ack() error {
 	return nil
 }
 
-func (b *NoopBroker) BatchPublish(ctx context.Context, msgs []*Message, opts ...PublishOption) error {
-	return b.funcBatchPublish(ctx, msgs, opts...)
+func (m *noopMessage) Body() []byte {
+	return m.body
 }
 
-func (b *NoopBroker) fnPublish(_ context.Context, _ string, _ *Message, _ ...PublishOption) error {
+func (m *noopMessage) Header() metadata.Metadata {
+	return m.hdr
+}
+
+func (m *noopMessage) Context() context.Context {
+	return m.ctx
+}
+
+func (m *noopMessage) Topic() string {
+	return ""
+}
+
+func (m *noopMessage) Unmarshal(dst interface{}, opts ...codec.Option) error {
+	return m.c.Unmarshal(m.body, dst)
+}
+
+func (b *NoopBroker) NewMessage(ctx context.Context, hdr metadata.Metadata, body interface{}, opts ...MessageOption) (Message, error) {
+	options := NewMessageOptions(opts...)
+	if options.ContentType == "" {
+		options.ContentType = b.opts.ContentType
+	}
+	m := &noopMessage{ctx: ctx, hdr: hdr, opts: options}
+	c, err := b.newCodec(m.opts.ContentType)
+	if err == nil {
+		m.body, err = c.Marshal(body)
+	}
+	if err != nil {
+		return nil, err
+	}
+
+	return m, nil
+}
+
+func (b *NoopBroker) fnPublish(_ context.Context, _ string, _ ...Message) error {
 	return nil
 }
 
-func (b *NoopBroker) Publish(ctx context.Context, topic string, msg *Message, opts ...PublishOption) error {
-	return b.funcPublish(ctx, topic, msg, opts...)
+func (b *NoopBroker) Publish(ctx context.Context, topic string, msg ...Message) error {
+	return b.funcPublish(ctx, topic, msg...)
 }
 
 type NoopSubscriber struct {
-	ctx          context.Context
-	topic        string
-	handler      Handler
-	batchHandler BatchHandler
-	opts         SubscribeOptions
+	ctx     context.Context
+	topic   string
+	handler interface{}
+	opts    SubscribeOptions
 }
 
-func (b *NoopBroker) fnBatchSubscribe(ctx context.Context, topic string, handler BatchHandler, opts ...SubscribeOption) (Subscriber, error) {
-	return &NoopSubscriber{ctx: ctx, topic: topic, opts: NewSubscribeOptions(opts...), batchHandler: handler}, nil
-}
-
-func (b *NoopBroker) BatchSubscribe(ctx context.Context, topic string, handler BatchHandler, opts ...SubscribeOption) (Subscriber, error) {
-	return b.funcBatchSubscribe(ctx, topic, handler, opts...)
-}
-
-func (b *NoopBroker) fnSubscribe(ctx context.Context, topic string, handler Handler, opts ...SubscribeOption) (Subscriber, error) {
+func (b *NoopBroker) fnSubscribe(ctx context.Context, topic string, handler interface{}, opts ...SubscribeOption) (Subscriber, error) {
 	return &NoopSubscriber{ctx: ctx, topic: topic, opts: NewSubscribeOptions(opts...), handler: handler}, nil
 }
 
-func (b *NoopBroker) Subscribe(ctx context.Context, topic string, handler Handler, opts ...SubscribeOption) (Subscriber, error) {
+func (b *NoopBroker) Subscribe(ctx context.Context, topic string, handler interface{}, opts ...SubscribeOption) (Subscriber, error) {
 	return b.funcSubscribe(ctx, topic, handler, opts...)
 }
 

broker/noop_test.go

@@ -10,9 +10,9 @@ type testHook struct {
 }
 
 func (t *testHook) Publish1(fn FuncPublish) FuncPublish {
-	return func(ctx context.Context, topic string, msg *Message, opts ...PublishOption) error {
+	return func(ctx context.Context, topic string, messages ...Message) error {
 		t.f = true
-		return fn(ctx, topic, msg, opts...)
+		return fn(ctx, topic, messages...)
 	}
 }
 

broker/options.go

@@ -5,13 +5,13 @@ import (
 	"crypto/tls"
 	"time"
 
-	"go.unistack.org/micro/v3/codec"
-	"go.unistack.org/micro/v3/logger"
-	"go.unistack.org/micro/v3/meter"
-	"go.unistack.org/micro/v3/options"
-	"go.unistack.org/micro/v3/register"
-	"go.unistack.org/micro/v3/sync"
-	"go.unistack.org/micro/v3/tracer"
+	"go.unistack.org/micro/v4/codec"
+	"go.unistack.org/micro/v4/logger"
+	"go.unistack.org/micro/v4/meter"
+	"go.unistack.org/micro/v4/options"
+	"go.unistack.org/micro/v4/register"
+	"go.unistack.org/micro/v4/sync"
+	"go.unistack.org/micro/v4/tracer"
 )
 
 // Options struct
@@ -23,8 +23,8 @@ type Options struct {
 	Tracer tracer.Tracer
 	// Register can be used for clustering
 	Register register.Register
-	// Codec holds the codec for marshal/unmarshal
-	Codec codec.Codec
+	// Codecs holds the codecs for marshal/unmarshal based on content-type
+	Codecs map[string]codec.Codec
 	// Logger used for logging
 	Logger logger.Logger
 	// Meter used for metrics
@@ -37,11 +37,6 @@ type Options struct {
 	// TLSConfig holds tls.TLSConfig options
 	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
-
 	// Addrs holds the broker address
 	Addrs []string
 	// Hooks can be run before broker Publish/BatchPublish and
@@ -50,6 +45,9 @@ type Options struct {
 
 	// GracefulTimeout contains time to wait to finish in flight requests
 	GracefulTimeout time.Duration
+
+	// ContentType will be used if no content-type set when creating message
+	ContentType string
 }
 
 // NewOptions create new Options
@@ -59,16 +57,22 @@ func NewOptions(opts ...Option) Options {
 		Logger:          logger.DefaultLogger,
 		Context:         context.Background(),
 		Meter:           meter.DefaultMeter,
-		Codec:           codec.DefaultCodec,
+		Codecs:          make(map[string]codec.Codec),
 		Tracer:          tracer.DefaultTracer,
 		GracefulTimeout: DefaultGracefulTimeout,
+		ContentType:     DefaultContentType,
 	}
+
 	for _, o := range opts {
 		o(&options)
 	}
+
 	return options
 }
 
+// DefaultContentType is the default content-type if not specified
+var DefaultContentType = ""
+
 // Context sets the context option
 func Context(ctx context.Context) Option {
 	return func(o *Options) {
@@ -76,17 +80,27 @@ func Context(ctx context.Context) Option {
 	}
 }
 
-// PublishOptions struct
-type PublishOptions struct {
-	// Context holds external options
-	Context context.Context
-	// BodyOnly flag says the message contains raw body bytes
-	BodyOnly bool
+// ContentType used by default if not specified
+func ContentType(ct string) Option {
+	return func(o *Options) {
+		o.ContentType = ct
+	}
 }
 
-// NewPublishOptions creates PublishOptions struct
-func NewPublishOptions(opts ...PublishOption) PublishOptions {
-	options := PublishOptions{
+// MessageOptions struct
+type MessageOptions struct {
+	// ContentType for message body
+	ContentType string
+	// BodyOnly flag says the message contains raw body bytes and don't need
+	// codec Marshal method
+	BodyOnly bool
+	// Context holds custom options
+	Context context.Context
+}
+
+// NewMessageOptions creates MessageOptions struct
+func NewMessageOptions(opts ...MessageOption) MessageOptions {
+	options := MessageOptions{
 		Context: context.Background(),
 	}
 	for _, o := range opts {
@@ -99,10 +113,6 @@ func NewPublishOptions(opts ...PublishOption) PublishOptions {
 type SubscribeOptions struct {
 	// Context holds external options
 	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
@@ -118,20 +128,20 @@ type SubscribeOptions struct {
 // Option func
 type Option func(*Options)
 
-// PublishOption func
-type PublishOption func(*PublishOptions)
+// MessageOption func
+type MessageOption func(*MessageOptions)
 
-// PublishBodyOnly publish only body of the message
-func PublishBodyOnly(b bool) PublishOption {
-	return func(o *PublishOptions) {
-		o.BodyOnly = b
+// MessageContentType sets message content-type that used to Marshal
+func MessageContentType(ct string) MessageOption {
+	return func(o *MessageOptions) {
+		o.ContentType = ct
 	}
 }
 
-// PublishContext sets the context
-func PublishContext(ctx context.Context) PublishOption {
-	return func(o *PublishOptions) {
-		o.Context = ctx
+// MessageBodyOnly publish only body of the message
+func MessageBodyOnly(b bool) MessageOption {
+	return func(o *MessageOptions) {
+		o.BodyOnly = b
 	}
 }
 
@@ -142,51 +152,10 @@ func Addrs(addrs ...string) Option {
 	}
 }
 
-// Codec sets the codec used for encoding/decoding used where
-// a broker does not support headers
-func Codec(c codec.Codec) Option {
+// Codec sets the codec used for encoding/decoding messages
+func Codec(ct string, c codec.Codec) Option {
 	return func(o *Options) {
-		o.Codec = c
-	}
-}
-
-// ErrorHandler will catch all broker errors that cant be handled
-// in normal way, for example Codec errors
-func ErrorHandler(h Handler) Option {
-	return func(o *Options) {
-		o.ErrorHandler = h
-	}
-}
-
-// 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 {
-	return func(o *SubscribeOptions) {
-		o.ErrorHandler = h
-	}
-}
-
-// 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 {
-	return func(o *SubscribeOptions) {
-		o.Group = name
+		o.Codecs[ct] = c
 	}
 }
 
@@ -253,14 +222,6 @@ func SubscribeContext(ctx context.Context) SubscribeOption {
 	}
 }
 
-// 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 {

broker/subscriber.go

@@ -0,0 +1,14 @@
+package broker
+
+// IsValidHandler func signature
+func IsValidHandler(sub interface{}) error {
+	switch sub.(type) {
+	default:
+		return ErrInvalidHandler
+	case func(Message) error:
+		break
+	case func([]Message) error:
+		break
+	}
+	return nil
+}

client/backoff.go

@@ -5,7 +5,7 @@ import (
 	"math"
 	"time"
 
-	"go.unistack.org/micro/v3/util/backoff"
+	"go.unistack.org/micro/v4/util/backoff"
 )
 
 // BackoffFunc is the backoff call func

client/client.go

@@ -5,8 +5,8 @@ import (
 	"context"
 	"time"
 
-	"go.unistack.org/micro/v3/codec"
-	"go.unistack.org/micro/v3/metadata"
+	"go.unistack.org/micro/v4/codec"
+	"go.unistack.org/micro/v4/metadata"
 )
 
 var (
@@ -29,40 +29,24 @@ var (
 )
 
 // Client is the interface used to make requests to services.
-// It supports Request/Response via Transport and Publishing via the Broker.
 // It also supports bidirectional streaming of requests.
 type Client interface {
 	Name() string
 	Init(opts ...Option) error
 	Options() Options
-	NewMessage(topic string, msg interface{}, opts ...MessageOption) Message
 	NewRequest(service string, endpoint string, req interface{}, opts ...RequestOption) Request
 	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
 }
 
 type (
-	FuncCall         func(ctx context.Context, req Request, rsp interface{}, opts ...CallOption) error
-	HookCall         func(next FuncCall) FuncCall
-	FuncStream       func(ctx context.Context, req Request, opts ...CallOption) (Stream, error)
-	HookStream       func(next FuncStream) FuncStream
-	FuncPublish      func(ctx context.Context, msg Message, opts ...PublishOption) error
-	HookPublish      func(next FuncPublish) FuncPublish
-	FuncBatchPublish func(ctx context.Context, msg []Message, opts ...PublishOption) error
-	HookBatchPublish func(next FuncBatchPublish) FuncBatchPublish
+	FuncCall   func(ctx context.Context, req Request, rsp interface{}, opts ...CallOption) error
+	HookCall   func(next FuncCall) FuncCall
+	FuncStream func(ctx context.Context, req Request, opts ...CallOption) (Stream, error)
+	HookStream func(next FuncStream) FuncStream
 )
 
-// Message is the interface for publishing asynchronously
-type Message interface {
-	Topic() string
-	Payload() interface{}
-	ContentType() string
-	Metadata() metadata.Metadata
-}
-
 // Request is the interface for a synchronous request used by Call or Stream
 type Request interface {
 	// The service to call
@@ -121,11 +105,5 @@ type Option func(*Options)
 // CallOption used by Call or Stream
 type CallOption func(*CallOptions)
 
-// PublishOption used by Publish
-type PublishOption func(*PublishOptions)
-
-// MessageOption used by NewMessage
-type MessageOption func(*MessageOptions)
-
 // RequestOption used by NewRequest
 type RequestOption func(*RequestOptions)

client/context.go

@@ -32,16 +32,6 @@ func NewContext(ctx context.Context, c Client) context.Context {
 	return context.WithValue(ctx, clientKey{}, c)
 }
 
-// SetPublishOption returns a function to setup a context with given value
-func SetPublishOption(k, v interface{}) PublishOption {
-	return func(o *PublishOptions) {
-		if o.Context == nil {
-			o.Context = context.Background()
-		}
-		o.Context = context.WithValue(o.Context, k, v)
-	}
-}
-
 // SetCallOption returns a function to setup a context with given value
 func SetCallOption(k, v interface{}) CallOption {
 	return func(o *CallOptions) {

client/context_test.go

@@ -39,17 +39,6 @@ func TestNewNilContext(t *testing.T) {
 	}
 }
 
-func TestSetPublishOption(t *testing.T) {
-	type key struct{}
-	o := SetPublishOption(key{}, "test")
-	opts := &PublishOptions{}
-	o(opts)
-
-	if v, ok := opts.Context.Value(key{}).(string); !ok || v == "" {
-		t.Fatal("SetPublishOption not works")
-	}
-}
-
 func TestSetCallOption(t *testing.T) {
 	type key struct{}
 	o := SetCallOption(key{}, "test")

client/lookup.go

@@ -4,8 +4,8 @@ import (
 	"context"
 	"sort"
 
-	"go.unistack.org/micro/v3/errors"
-	"go.unistack.org/micro/v3/router"
+	"go.unistack.org/micro/v4/errors"
+	"go.unistack.org/micro/v4/router"
 )
 
 // LookupFunc is used to lookup routes for a service

client/noop.go

@@ -3,32 +3,27 @@ package client
 import (
 	"context"
 	"fmt"
-	"os"
 	"strconv"
 	"time"
 
-	"go.unistack.org/micro/v3/broker"
-	"go.unistack.org/micro/v3/codec"
-	"go.unistack.org/micro/v3/errors"
-	"go.unistack.org/micro/v3/metadata"
-	"go.unistack.org/micro/v3/options"
-	"go.unistack.org/micro/v3/selector"
-	"go.unistack.org/micro/v3/semconv"
-	"go.unistack.org/micro/v3/tracer"
+	"go.unistack.org/micro/v4/codec"
+	"go.unistack.org/micro/v4/errors"
+	"go.unistack.org/micro/v4/metadata"
+	"go.unistack.org/micro/v4/options"
+	"go.unistack.org/micro/v4/selector"
+	"go.unistack.org/micro/v4/semconv"
+	"go.unistack.org/micro/v4/tracer"
 )
 
-type noopClient struct {
-	funcPublish      FuncPublish
-	funcBatchPublish FuncBatchPublish
-	funcCall         FuncCall
-	funcStream       FuncStream
-	opts             Options
+// DefaultCodecs will be used to encode/decode data
+var DefaultCodecs = map[string]codec.Codec{
+	"application/octet-stream": codec.NewCodec(),
 }
 
-type noopMessage struct {
-	topic   string
-	payload interface{}
-	opts    MessageOptions
+type noopClient struct {
+	funcCall   FuncCall
+	funcStream FuncStream
+	opts       Options
 }
 
 type noopRequest struct {
@@ -47,8 +42,6 @@ func NewClient(opts ...Option) Client {
 
 	n.funcCall = n.fnCall
 	n.funcStream = n.fnStream
-	n.funcPublish = n.fnPublish
-	n.funcBatchPublish = n.fnBatchPublish
 
 	return n
 }
@@ -153,29 +146,6 @@ func (n *noopStream) CloseSend() error {
 	return n.err
 }
 
-func (n *noopMessage) Topic() string {
-	return n.topic
-}
-
-func (n *noopMessage) Payload() interface{} {
-	return n.payload
-}
-
-func (n *noopMessage) ContentType() string {
-	return n.opts.ContentType
-}
-
-func (n *noopMessage) Metadata() metadata.Metadata {
-	return n.opts.Metadata
-}
-
-func (n *noopClient) newCodec(contentType string) (codec.Codec, error) {
-	if cf, ok := n.opts.Codecs[contentType]; ok {
-		return cf, nil
-	}
-	return nil, codec.ErrUnknownContentType
-}
-
 func (n *noopClient) Init(opts ...Option) error {
 	for _, o := range opts {
 		o(&n.opts)
@@ -183,8 +153,6 @@ func (n *noopClient) Init(opts ...Option) error {
 
 	n.funcCall = n.fnCall
 	n.funcStream = n.fnStream
-	n.funcPublish = n.fnPublish
-	n.funcBatchPublish = n.fnBatchPublish
 
 	n.opts.Hooks.EachPrev(func(hook options.Hook) {
 		switch h := hook.(type) {
@@ -192,10 +160,6 @@ func (n *noopClient) Init(opts ...Option) error {
 			n.funcCall = h(n.funcCall)
 		case HookStream:
 			n.funcStream = h(n.funcStream)
-		case HookPublish:
-			n.funcPublish = h(n.funcPublish)
-		case HookBatchPublish:
-			n.funcBatchPublish = h(n.funcBatchPublish)
 		}
 	})
 
@@ -368,11 +332,6 @@ func (n *noopClient) NewRequest(service, endpoint string, _ interface{}, _ ...Re
 	return &noopRequest{service: service, endpoint: endpoint}
 }
 
-func (n *noopClient) NewMessage(topic string, msg interface{}, opts ...MessageOption) Message {
-	options := NewMessageOptions(append([]MessageOption{MessageContentType(n.opts.ContentType)}, opts...)...)
-	return &noopMessage{topic: topic, payload: msg, opts: options}
-}
-
 func (n *noopClient) Stream(ctx context.Context, req Request, opts ...CallOption) (Stream, error) {
 	ts := time.Now()
 	n.opts.Meter.Counter(semconv.ClientRequestInflight, "endpoint", req.Endpoint()).Inc()
@@ -541,90 +500,3 @@ func (n *noopClient) fnStream(ctx context.Context, req Request, opts ...CallOpti
 func (n *noopClient) stream(ctx context.Context, _ string, _ Request, _ CallOptions) (Stream, error) {
 	return &noopStream{ctx: ctx}, nil
 }
-
-func (n *noopClient) BatchPublish(ctx context.Context, ps []Message, opts ...PublishOption) error {
-	return n.funcBatchPublish(ctx, ps, opts...)
-}
-
-func (n *noopClient) fnBatchPublish(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.funcPublish(ctx, p, opts...)
-}
-
-func (n *noopClient) fnPublish(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...)
-
-	msgs := make([]*broker.Message, 0, len(ps))
-
-	// get proxy
-	exchange := ""
-	if v, ok := os.LookupEnv("MICRO_PROXY"); ok {
-		exchange = v
-	}
-	// get the exchange
-	if len(options.Exchange) > 0 {
-		exchange = options.Exchange
-	}
-
-	omd, ok := metadata.FromOutgoingContext(ctx)
-	if !ok {
-		omd = metadata.New(0)
-	}
-
-	for _, p := range ps {
-		md := metadata.Copy(omd)
-		topic := p.Topic()
-		if len(exchange) > 0 {
-			topic = exchange
-		}
-		md[metadata.HeaderTopic] = topic
-		iter := p.Metadata().Iterator()
-		var k, v string
-		for iter.Next(&k, &v) {
-			md.Set(k, v)
-		}
-
-		md[metadata.HeaderContentType] = p.ContentType()
-
-		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", "%s", err)
-			}
-
-			// set the body
-			b, err := cf.Marshal(p.Payload())
-			if err != nil {
-				return errors.InternalServerError("go.micro.client", "%s", err)
-			}
-			body = b
-		}
-
-		msgs = append(msgs, &broker.Message{Header: md, Body: body})
-	}
-
-	if len(msgs) == 1 {
-		return n.opts.Broker.Publish(ctx, msgs[0].Header[metadata.HeaderTopic], msgs[0],
-			broker.PublishContext(options.Context),
-			broker.PublishBodyOnly(options.BodyOnly),
-		)
-	}
-
-	return n.opts.Broker.BatchPublish(ctx, msgs,
-		broker.PublishContext(options.Context),
-		broker.PublishBodyOnly(options.BodyOnly),
-	)
-}

client/noop_test.go

@@ -1,37 +0,0 @@
-package client
-
-import (
-	"context"
-	"testing"
-
-	"go.unistack.org/micro/v3/codec"
-)
-
-type testHook struct {
-	f bool
-}
-
-func (t *testHook) Publish(fn FuncPublish) FuncPublish {
-	return func(ctx context.Context, msg Message, opts ...PublishOption) error {
-		t.f = true
-		return fn(ctx, msg, opts...)
-	}
-}
-
-func TestNoopHook(t *testing.T) {
-	h := &testHook{}
-
-	c := NewClient(Codec("application/octet-stream", codec.NewCodec()), Hooks(HookPublish(h.Publish)))
-
-	if err := c.Init(); err != nil {
-		t.Fatal(err)
-	}
-
-	if err := c.Publish(context.TODO(), c.NewMessage("", nil, MessageContentType("application/octet-stream"))); err != nil {
-		t.Fatal(err)
-	}
-
-	if !h.f {
-		t.Fatal("hook not works")
-	}
-}

client/options.go

@@ -6,17 +6,17 @@ import (
 	"net"
 	"time"
 
-	"go.unistack.org/micro/v3/broker"
-	"go.unistack.org/micro/v3/codec"
-	"go.unistack.org/micro/v3/logger"
-	"go.unistack.org/micro/v3/metadata"
-	"go.unistack.org/micro/v3/meter"
-	"go.unistack.org/micro/v3/options"
-	"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"
+	"go.unistack.org/micro/v4/broker"
+	"go.unistack.org/micro/v4/codec"
+	"go.unistack.org/micro/v4/logger"
+	"go.unistack.org/micro/v4/metadata"
+	"go.unistack.org/micro/v4/meter"
+	"go.unistack.org/micro/v4/options"
+	"go.unistack.org/micro/v4/register"
+	"go.unistack.org/micro/v4/router"
+	"go.unistack.org/micro/v4/selector"
+	"go.unistack.org/micro/v4/selector/random"
+	"go.unistack.org/micro/v4/tracer"
 )
 
 // Options holds client options
@@ -137,43 +137,6 @@ func Context(ctx context.Context) Option {
 	}
 }
 
-// NewPublishOptions create new PublishOptions struct from option
-func NewPublishOptions(opts ...PublishOption) PublishOptions {
-	options := PublishOptions{}
-	for _, o := range opts {
-		o(&options)
-	}
-	return options
-}
-
-// PublishOptions holds publish options
-type PublishOptions struct {
-	// 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
-func NewMessageOptions(opts ...MessageOption) MessageOptions {
-	options := MessageOptions{Metadata: metadata.New(1)}
-	for _, o := range opts {
-		o(&options)
-	}
-	return options
-}
-
-// MessageOptions holds client message options
-type MessageOptions struct {
-	// Metadata additional metadata
-	Metadata metadata.Metadata
-	// ContentType specify content-type of message
-	// deprecated
-	ContentType string
-}
-
 // NewRequestOptions creates new RequestOptions struct
 func NewRequestOptions(opts ...RequestOption) RequestOptions {
 	options := RequestOptions{}
@@ -198,7 +161,7 @@ func NewOptions(opts ...Option) Options {
 	options := Options{
 		Context:     context.Background(),
 		ContentType: DefaultContentType,
-		Codecs:      make(map[string]codec.Codec),
+		Codecs:      DefaultCodecs,
 		CallOptions: CallOptions{
 			Context:        context.Background(),
 			Backoff:        DefaultBackoff,
@@ -374,43 +337,6 @@ 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) {
-		o.Context = ctx
-	}
-}
-
 // WithContextDialer pass ContextDialer to client call
 func WithContextDialer(fn func(context.Context, string) (net.Conn, error)) CallOption {
 	return func(o *CallOptions) {
@@ -522,30 +448,6 @@ func WithSelectOptions(sops ...selector.SelectOption) CallOption {
 	}
 }
 
-// WithMessageContentType sets the message content type
-// Deprecated
-func WithMessageContentType(ct string) MessageOption {
-	return func(o *MessageOptions) {
-		o.Metadata.Set(metadata.HeaderContentType, ct)
-		o.ContentType = ct
-	}
-}
-
-// MessageContentType sets the message content type
-func MessageContentType(ct string) MessageOption {
-	return func(o *MessageOptions) {
-		o.Metadata.Set(metadata.HeaderContentType, ct)
-		o.ContentType = ct
-	}
-}
-
-// MessageMetadata sets the message metadata
-func MessageMetadata(k, v string) MessageOption {
-	return func(o *MessageOptions) {
-		o.Metadata.Set(k, v)
-	}
-}
-
 // 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"
 
-	"go.unistack.org/micro/v3/errors"
+	"go.unistack.org/micro/v4/errors"
 )
 
 // RetryFunc that returning either false or a non-nil error will result in the call not being retried

client/retry_test.go

@@ -5,7 +5,7 @@ import (
 	"fmt"
 	"testing"
 
-	"go.unistack.org/micro/v3/errors"
+	"go.unistack.org/micro/v4/errors"
 )
 
 func TestRetryAlways(t *testing.T) {

client/test_request.go

@@ -1,7 +1,7 @@
 package client
 
 import (
-	"go.unistack.org/micro/v3/codec"
+	"go.unistack.org/micro/v4/codec"
 )
 
 type testRequest struct {

cluster/cluster.go

@@ -3,7 +3,7 @@ package cluster
 import (
 	"context"
 
-	"go.unistack.org/micro/v3/metadata"
+	"go.unistack.org/micro/v4/metadata"
 )
 
 // Message sent to member in cluster

cluster/sql/cluster.go

@@ -1,531 +0,0 @@
-package sql
-
-import (
-	"context"
-	"database/sql"
-	"errors"
-	"fmt"
-	"math"
-	"reflect"
-	"time"
-	"unsafe"
-
-	"golang.yandex/hasql/v2"
-)
-
-var errNoAliveNodes = errors.New("no alive nodes")
-
-func newSQLRowError() *sql.Row {
-	row := &sql.Row{}
-	t := reflect.TypeOf(row).Elem()
-	field, _ := t.FieldByName("err")
-	rowPtr := unsafe.Pointer(row)
-	errFieldPtr := unsafe.Pointer(uintptr(rowPtr) + field.Offset)
-	errPtr := (*error)(errFieldPtr)
-	*errPtr = errNoAliveNodes
-	return row
-}
-
-type ClusterQuerier interface {
-	Querier
-	WaitForNodes(ctx context.Context, criterion ...hasql.NodeStateCriterion) error
-}
-
-type Querier interface {
-	// Basic connection methods
-	PingContext(ctx context.Context) error
-	Close() error
-
-	// Query methods with context
-	ExecContext(ctx context.Context, query string, args ...interface{}) (sql.Result, error)
-	QueryContext(ctx context.Context, query string, args ...interface{}) (*sql.Rows, error)
-	QueryRowContext(ctx context.Context, query string, args ...interface{}) *sql.Row
-
-	// Prepared statements with context
-	PrepareContext(ctx context.Context, query string) (*sql.Stmt, error)
-
-	// Transaction management with context
-	BeginTx(ctx context.Context, opts *sql.TxOptions) (*sql.Tx, error)
-
-	// Connection pool management
-	SetConnMaxLifetime(d time.Duration)
-	SetConnMaxIdleTime(d time.Duration)
-	SetMaxOpenConns(n int)
-	SetMaxIdleConns(n int)
-	Stats() sql.DBStats
-
-	Conn(ctx context.Context) (*sql.Conn, error)
-}
-
-var (
-	ErrClusterChecker    = errors.New("cluster node checker required")
-	ErrClusterDiscoverer = errors.New("cluster node discoverer required")
-	ErrClusterPicker     = errors.New("cluster node picker required")
-)
-
-type Cluster struct {
-	hasql   *hasql.Cluster[Querier]
-	options ClusterOptions
-}
-
-// NewCluster returns Querier that provides cluster of nodes
-func NewCluster[T Querier](opts ...ClusterOption) (ClusterQuerier, error) {
-	options := ClusterOptions{Context: context.Background()}
-	for _, opt := range opts {
-		opt(&options)
-	}
-	if options.NodeChecker == nil {
-		return nil, ErrClusterChecker
-	}
-	if options.NodeDiscoverer == nil {
-		return nil, ErrClusterDiscoverer
-	}
-	if options.NodePicker == nil {
-		return nil, ErrClusterPicker
-	}
-
-	if options.Retries < 1 {
-		options.Retries = 1
-	}
-
-	if options.NodeStateCriterion == 0 {
-		options.NodeStateCriterion = hasql.Primary
-	}
-
-	options.Options = append(options.Options, hasql.WithNodePicker(options.NodePicker))
-	if p, ok := options.NodePicker.(*CustomPicker[Querier]); ok {
-		p.opts.Priority = options.NodePriority
-	}
-
-	c, err := hasql.NewCluster(
-		options.NodeDiscoverer,
-		options.NodeChecker,
-		options.Options...,
-	)
-	if err != nil {
-		return nil, err
-	}
-
-	return &Cluster{hasql: c, options: options}, nil
-}
-
-// compile time guard
-var _ hasql.NodePicker[Querier] = (*CustomPicker[Querier])(nil)
-
-type nodeStateCriterionKey struct{}
-
-// NodeStateCriterion inject hasql.NodeStateCriterion to context
-func NodeStateCriterion(ctx context.Context, c hasql.NodeStateCriterion) context.Context {
-	return context.WithValue(ctx, nodeStateCriterionKey{}, c)
-}
-
-// CustomPickerOptions holds options to pick nodes
-type CustomPickerOptions struct {
-	MaxLag   int
-	Priority map[string]int32
-	Retries  int
-}
-
-// CustomPickerOption func apply option to CustomPickerOptions
-type CustomPickerOption func(*CustomPickerOptions)
-
-// CustomPickerMaxLag specifies max lag for which node can be used
-func CustomPickerMaxLag(n int) CustomPickerOption {
-	return func(o *CustomPickerOptions) {
-		o.MaxLag = n
-	}
-}
-
-// NewCustomPicker creates new node picker
-func NewCustomPicker[T Querier](opts ...CustomPickerOption) *CustomPicker[Querier] {
-	options := CustomPickerOptions{}
-	for _, o := range opts {
-		o(&options)
-	}
-	return &CustomPicker[Querier]{opts: options}
-}
-
-// CustomPicker holds node picker options
-type CustomPicker[T Querier] struct {
-	opts CustomPickerOptions
-}
-
-// PickNode used to return specific node
-func (p *CustomPicker[T]) PickNode(cnodes []hasql.CheckedNode[T]) hasql.CheckedNode[T] {
-	for _, n := range cnodes {
-		fmt.Printf("node %s\n", n.Node.String())
-	}
-	return cnodes[0]
-}
-
-func (p *CustomPicker[T]) getPriority(nodeName string) int32 {
-	if prio, ok := p.opts.Priority[nodeName]; ok {
-		return prio
-	}
-	return math.MaxInt32 // Default to lowest priority
-}
-
-// CompareNodes used to sort nodes
-func (p *CustomPicker[T]) CompareNodes(a, b hasql.CheckedNode[T]) int {
-	fmt.Printf("CompareNodes %s %s\n", a.Node.String(), b.Node.String())
-	// Get replication lag values
-	aLag := a.Info.(interface{ ReplicationLag() int }).ReplicationLag()
-	bLag := b.Info.(interface{ ReplicationLag() int }).ReplicationLag()
-
-	// First check that lag lower then MaxLag
-	if aLag > p.opts.MaxLag && bLag > p.opts.MaxLag {
-		fmt.Printf("CompareNodes aLag > p.opts.MaxLag && bLag > p.opts.MaxLag\n")
-		return 0 // both are equal
-	}
-
-	// If one node exceeds MaxLag and the other doesn't, prefer the one that doesn't
-	if aLag > p.opts.MaxLag {
-		fmt.Printf("CompareNodes aLag > p.opts.MaxLag\n")
-		return 1 // b is better
-	}
-	if bLag > p.opts.MaxLag {
-		fmt.Printf("CompareNodes bLag > p.opts.MaxLag\n")
-		return -1 // a is better
-	}
-
-	// Get node priorities
-	aPrio := p.getPriority(a.Node.String())
-	bPrio := p.getPriority(b.Node.String())
-
-	// if both priority equals
-	if aPrio == bPrio {
-		fmt.Printf("CompareNodes aPrio == bPrio\n")
-		// First compare by replication lag
-		if aLag < bLag {
-			fmt.Printf("CompareNodes aLag < bLag\n")
-			return -1
-		}
-		if aLag > bLag {
-			fmt.Printf("CompareNodes aLag > bLag\n")
-			return 1
-		}
-		// If replication lag is equal, compare by latency
-		aLatency := a.Info.(interface{ Latency() time.Duration }).Latency()
-		bLatency := b.Info.(interface{ Latency() time.Duration }).Latency()
-
-		if aLatency < bLatency {
-			return -1
-		}
-		if aLatency > bLatency {
-			return 1
-		}
-
-		// If lag and latency is equal
-		return 0
-	}
-
-	// If priorities are different, prefer the node with lower priority value
-	if aPrio < bPrio {
-		return -1
-	}
-
-	return 1
-}
-
-// ClusterOptions contains cluster specific options
-type ClusterOptions struct {
-	NodeChecker        hasql.NodeChecker
-	NodePicker         hasql.NodePicker[Querier]
-	NodeDiscoverer     hasql.NodeDiscoverer[Querier]
-	Options            []hasql.ClusterOpt[Querier]
-	Context            context.Context
-	Retries            int
-	NodePriority       map[string]int32
-	NodeStateCriterion hasql.NodeStateCriterion
-}
-
-// ClusterOption apply cluster options to ClusterOptions
-type ClusterOption func(*ClusterOptions)
-
-// WithClusterNodeChecker pass hasql.NodeChecker to cluster options
-func WithClusterNodeChecker(c hasql.NodeChecker) ClusterOption {
-	return func(o *ClusterOptions) {
-		o.NodeChecker = c
-	}
-}
-
-// WithClusterNodePicker pass hasql.NodePicker to cluster options
-func WithClusterNodePicker(p hasql.NodePicker[Querier]) ClusterOption {
-	return func(o *ClusterOptions) {
-		o.NodePicker = p
-	}
-}
-
-// WithClusterNodeDiscoverer pass hasql.NodeDiscoverer to cluster options
-func WithClusterNodeDiscoverer(d hasql.NodeDiscoverer[Querier]) ClusterOption {
-	return func(o *ClusterOptions) {
-		o.NodeDiscoverer = d
-	}
-}
-
-// WithRetries retry count on other nodes in case of error
-func WithRetries(n int) ClusterOption {
-	return func(o *ClusterOptions) {
-		o.Retries = n
-	}
-}
-
-// WithClusterContext pass context.Context to cluster options and used for checks
-func WithClusterContext(ctx context.Context) ClusterOption {
-	return func(o *ClusterOptions) {
-		o.Context = ctx
-	}
-}
-
-// WithClusterOptions pass hasql.ClusterOpt
-func WithClusterOptions(opts ...hasql.ClusterOpt[Querier]) ClusterOption {
-	return func(o *ClusterOptions) {
-		o.Options = append(o.Options, opts...)
-	}
-}
-
-// WithClusterNodeStateCriterion pass default hasql.NodeStateCriterion
-func WithClusterNodeStateCriterion(c hasql.NodeStateCriterion) ClusterOption {
-	return func(o *ClusterOptions) {
-		o.NodeStateCriterion = c
-	}
-}
-
-type ClusterNode struct {
-	Name     string
-	DB       Querier
-	Priority int32
-}
-
-// WithClusterNodes create cluster with static NodeDiscoverer
-func WithClusterNodes(cns ...ClusterNode) ClusterOption {
-	return func(o *ClusterOptions) {
-		nodes := make([]*hasql.Node[Querier], 0, len(cns))
-		if o.NodePriority == nil {
-			o.NodePriority = make(map[string]int32, len(cns))
-		}
-		for _, cn := range cns {
-			nodes = append(nodes, hasql.NewNode(cn.Name, cn.DB))
-			if cn.Priority == 0 {
-				cn.Priority = math.MaxInt32
-			}
-			o.NodePriority[cn.Name] = cn.Priority
-		}
-		o.NodeDiscoverer = hasql.NewStaticNodeDiscoverer(nodes...)
-	}
-}
-
-func (c *Cluster) BeginTx(ctx context.Context, opts *sql.TxOptions) (*sql.Tx, error) {
-	var tx *sql.Tx
-	var err error
-
-	retries := 0
-	c.hasql.NodesIter(c.getNodeStateCriterion(ctx))(func(n *hasql.Node[Querier]) bool {
-		for ; retries < c.options.Retries; retries++ {
-			if tx, err = n.DB().BeginTx(ctx, opts); err != nil && retries >= c.options.Retries {
-				return true
-			}
-		}
-		return false
-	})
-
-	if tx == nil && err == nil {
-		err = errNoAliveNodes
-	}
-
-	return tx, err
-}
-
-func (c *Cluster) Close() error {
-	return c.hasql.Close()
-}
-
-func (c *Cluster) Conn(ctx context.Context) (*sql.Conn, error) {
-	var conn *sql.Conn
-	var err error
-
-	retries := 0
-	c.hasql.NodesIter(c.getNodeStateCriterion(ctx))(func(n *hasql.Node[Querier]) bool {
-		for ; retries < c.options.Retries; retries++ {
-			if conn, err = n.DB().Conn(ctx); err != nil && retries >= c.options.Retries {
-				return true
-			}
-		}
-		return false
-	})
-
-	if conn == nil && err == nil {
-		err = errNoAliveNodes
-	}
-
-	return conn, err
-}
-
-func (c *Cluster) ExecContext(ctx context.Context, query string, args ...interface{}) (sql.Result, error) {
-	var res sql.Result
-	var err error
-
-	retries := 0
-	c.hasql.NodesIter(c.getNodeStateCriterion(ctx))(func(n *hasql.Node[Querier]) bool {
-		for ; retries < c.options.Retries; retries++ {
-			if res, err = n.DB().ExecContext(ctx, query, args...); err != nil && retries >= c.options.Retries {
-				return true
-			}
-		}
-		return false
-	})
-
-	if res == nil && err == nil {
-		err = errNoAliveNodes
-	}
-
-	return res, err
-}
-
-func (c *Cluster) PrepareContext(ctx context.Context, query string) (*sql.Stmt, error) {
-	var res *sql.Stmt
-	var err error
-
-	retries := 0
-	c.hasql.NodesIter(c.getNodeStateCriterion(ctx))(func(n *hasql.Node[Querier]) bool {
-		for ; retries < c.options.Retries; retries++ {
-			if res, err = n.DB().PrepareContext(ctx, query); err != nil && retries >= c.options.Retries {
-				return true
-			}
-		}
-		return false
-	})
-
-	if res == nil && err == nil {
-		err = errNoAliveNodes
-	}
-
-	return res, err
-}
-
-func (c *Cluster) QueryContext(ctx context.Context, query string, args ...interface{}) (*sql.Rows, error) {
-	var res *sql.Rows
-	var err error
-
-	retries := 0
-	c.hasql.NodesIter(c.getNodeStateCriterion(ctx))(func(n *hasql.Node[Querier]) bool {
-		for ; retries < c.options.Retries; retries++ {
-			if res, err = n.DB().QueryContext(ctx, query); err != nil && err != sql.ErrNoRows && retries >= c.options.Retries {
-				return true
-			}
-		}
-		return false
-	})
-
-	if res == nil && err == nil {
-		err = errNoAliveNodes
-	}
-
-	return res, err
-}
-
-func (c *Cluster) QueryRowContext(ctx context.Context, query string, args ...interface{}) *sql.Row {
-	var res *sql.Row
-
-	retries := 0
-	c.hasql.NodesIter(c.getNodeStateCriterion(ctx))(func(n *hasql.Node[Querier]) bool {
-		for ; retries < c.options.Retries; retries++ {
-			res = n.DB().QueryRowContext(ctx, query, args...)
-			if res.Err() == nil {
-				return false
-			} else if res.Err() != nil && retries >= c.options.Retries {
-				return false
-			}
-		}
-		return true
-	})
-
-	if res == nil {
-		res = newSQLRowError()
-	}
-
-	return res
-}
-
-func (c *Cluster) PingContext(ctx context.Context) error {
-	var err error
-	var ok bool
-
-	retries := 0
-	c.hasql.NodesIter(c.getNodeStateCriterion(ctx))(func(n *hasql.Node[Querier]) bool {
-		ok = true
-		for ; retries < c.options.Retries; retries++ {
-			if err = n.DB().PingContext(ctx); err != nil && retries >= c.options.Retries {
-				return true
-			}
-		}
-		return false
-	})
-
-	if !ok {
-		err = errNoAliveNodes
-	}
-
-	return err
-}
-
-func (c *Cluster) WaitForNodes(ctx context.Context, criterions ...hasql.NodeStateCriterion) error {
-	for _, criterion := range criterions {
-		if _, err := c.hasql.WaitForNode(ctx, criterion); err != nil {
-			return err
-		}
-	}
-	return nil
-}
-
-func (c *Cluster) SetConnMaxLifetime(td time.Duration) {
-	c.hasql.NodesIter(hasql.NodeStateCriterion(hasql.Alive))(func(n *hasql.Node[Querier]) bool {
-		n.DB().SetConnMaxIdleTime(td)
-		return false
-	})
-}
-
-func (c *Cluster) SetConnMaxIdleTime(td time.Duration) {
-	c.hasql.NodesIter(hasql.NodeStateCriterion(hasql.Alive))(func(n *hasql.Node[Querier]) bool {
-		n.DB().SetConnMaxIdleTime(td)
-		return false
-	})
-}
-
-func (c *Cluster) SetMaxOpenConns(nc int) {
-	c.hasql.NodesIter(hasql.NodeStateCriterion(hasql.Alive))(func(n *hasql.Node[Querier]) bool {
-		n.DB().SetMaxOpenConns(nc)
-		return false
-	})
-}
-
-func (c *Cluster) SetMaxIdleConns(nc int) {
-	c.hasql.NodesIter(hasql.NodeStateCriterion(hasql.Alive))(func(n *hasql.Node[Querier]) bool {
-		n.DB().SetMaxIdleConns(nc)
-		return false
-	})
-}
-
-func (c *Cluster) Stats() sql.DBStats {
-	s := sql.DBStats{}
-	c.hasql.NodesIter(hasql.NodeStateCriterion(hasql.Alive))(func(n *hasql.Node[Querier]) bool {
-		st := n.DB().Stats()
-		s.Idle += st.Idle
-		s.InUse += st.InUse
-		s.MaxIdleClosed += st.MaxIdleClosed
-		s.MaxIdleTimeClosed += st.MaxIdleTimeClosed
-		s.MaxOpenConnections += st.MaxOpenConnections
-		s.OpenConnections += st.OpenConnections
-		s.WaitCount += st.WaitCount
-		s.WaitDuration += st.WaitDuration
-		return false
-	})
-	return s
-}
-
-func (c *Cluster) getNodeStateCriterion(ctx context.Context) hasql.NodeStateCriterion {
-	if v, ok := ctx.Value(nodeStateCriterionKey{}).(hasql.NodeStateCriterion); ok {
-		return v
-	}
-	return c.options.NodeStateCriterion
-}

cluster/sql/cluster_test.go

@@ -1,171 +0,0 @@
-package sql
-
-import (
-	"context"
-	"fmt"
-	"testing"
-	"time"
-
-	"github.com/DATA-DOG/go-sqlmock"
-	"golang.yandex/hasql/v2"
-)
-
-func TestNewCluster(t *testing.T) {
-	dbMaster, dbMasterMock, err := sqlmock.New(sqlmock.MonitorPingsOption(true))
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer dbMaster.Close()
-	dbMasterMock.MatchExpectationsInOrder(false)
-
-	dbMasterMock.ExpectQuery(`.*pg_is_in_recovery.*`).WillReturnRows(
-		sqlmock.NewRowsWithColumnDefinition(
-			sqlmock.NewColumn("role").OfType("int8", 0),
-			sqlmock.NewColumn("replication_lag").OfType("int8", 0)).
-			AddRow(1, 0)).
-		RowsWillBeClosed().
-		WithoutArgs()
-
-	dbMasterMock.ExpectQuery(`SELECT node_name as name`).WillReturnRows(
-		sqlmock.NewRows([]string{"name"}).
-			AddRow("master-dc1"))
-
-	dbDRMaster, dbDRMasterMock, err := sqlmock.New(sqlmock.MonitorPingsOption(true))
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer dbDRMaster.Close()
-	dbDRMasterMock.MatchExpectationsInOrder(false)
-
-	dbDRMasterMock.ExpectQuery(`.*pg_is_in_recovery.*`).WillReturnRows(
-		sqlmock.NewRowsWithColumnDefinition(
-			sqlmock.NewColumn("role").OfType("int8", 0),
-			sqlmock.NewColumn("replication_lag").OfType("int8", 0)).
-			AddRow(2, 40)).
-		RowsWillBeClosed().
-		WithoutArgs()
-
-	dbDRMasterMock.ExpectQuery(`SELECT node_name as name`).WillReturnRows(
-		sqlmock.NewRows([]string{"name"}).
-			AddRow("drmaster1-dc2"))
-
-	dbDRMasterMock.ExpectQuery(`SELECT node_name as name`).WillReturnRows(
-		sqlmock.NewRows([]string{"name"}).
-			AddRow("drmaster"))
-
-	dbSlaveDC1, dbSlaveDC1Mock, err := sqlmock.New(sqlmock.MonitorPingsOption(true))
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer dbSlaveDC1.Close()
-	dbSlaveDC1Mock.MatchExpectationsInOrder(false)
-
-	dbSlaveDC1Mock.ExpectQuery(`.*pg_is_in_recovery.*`).WillReturnRows(
-		sqlmock.NewRowsWithColumnDefinition(
-			sqlmock.NewColumn("role").OfType("int8", 0),
-			sqlmock.NewColumn("replication_lag").OfType("int8", 0)).
-			AddRow(2, 50)).
-		RowsWillBeClosed().
-		WithoutArgs()
-
-	dbSlaveDC1Mock.ExpectQuery(`SELECT node_name as name`).WillReturnRows(
-		sqlmock.NewRows([]string{"name"}).
-			AddRow("slave-dc1"))
-
-	dbSlaveDC2, dbSlaveDC2Mock, err := sqlmock.New(sqlmock.MonitorPingsOption(true))
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer dbSlaveDC2.Close()
-	dbSlaveDC1Mock.MatchExpectationsInOrder(false)
-
-	dbSlaveDC2Mock.ExpectQuery(`.*pg_is_in_recovery.*`).WillReturnRows(
-		sqlmock.NewRowsWithColumnDefinition(
-			sqlmock.NewColumn("role").OfType("int8", 0),
-			sqlmock.NewColumn("replication_lag").OfType("int8", 0)).
-			AddRow(2, 50)).
-		RowsWillBeClosed().
-		WithoutArgs()
-
-	dbSlaveDC2Mock.ExpectQuery(`SELECT node_name as name`).WillReturnRows(
-		sqlmock.NewRows([]string{"name"}).
-			AddRow("slave-dc1"))
-
-	tctx, cancel := context.WithTimeout(t.Context(), 10*time.Second)
-	defer cancel()
-
-	c, err := NewCluster[Querier](
-		WithClusterContext(tctx),
-		WithClusterNodeChecker(hasql.PostgreSQLChecker),
-		WithClusterNodePicker(NewCustomPicker[Querier](
-			CustomPickerMaxLag(100),
-		)),
-		WithClusterNodes(
-			ClusterNode{"slave-dc1", dbSlaveDC1, 1},
-			ClusterNode{"master-dc1", dbMaster, 1},
-			ClusterNode{"slave-dc2", dbSlaveDC2, 2},
-			ClusterNode{"drmaster1-dc2", dbDRMaster, 0},
-		),
-		WithClusterOptions(
-			hasql.WithUpdateInterval[Querier](2*time.Second),
-			hasql.WithUpdateTimeout[Querier](1*time.Second),
-		),
-	)
-	if err != nil {
-		t.Fatal(err)
-	}
-	defer c.Close()
-
-	if err = c.WaitForNodes(tctx, hasql.Primary, hasql.Standby); err != nil {
-		t.Fatal(err)
-	}
-
-	time.Sleep(500 * time.Millisecond)
-
-	node1Name := ""
-	fmt.Printf("check for Standby\n")
-	if row := c.QueryRowContext(NodeStateCriterion(tctx, hasql.Standby), "SELECT node_name as name"); row.Err() != nil {
-		t.Fatal(row.Err())
-	} else if err = row.Scan(&node1Name); err != nil {
-		t.Fatal(err)
-	} else if "slave-dc1" != node1Name {
-		t.Fatalf("invalid node name %s != %s", "slave-dc1", node1Name)
-	}
-
-	dbSlaveDC1Mock.ExpectQuery(`SELECT node_name as name`).WillReturnRows(
-		sqlmock.NewRows([]string{"name"}).
-			AddRow("slave-dc1"))
-
-	node2Name := ""
-	fmt.Printf("check for PreferStandby\n")
-	if row := c.QueryRowContext(NodeStateCriterion(tctx, hasql.PreferStandby), "SELECT node_name as name"); row.Err() != nil {
-		t.Fatal(row.Err())
-	} else if err = row.Scan(&node2Name); err != nil {
-		t.Fatal(err)
-	} else if "slave-dc1" != node2Name {
-		t.Fatalf("invalid node name %s != %s", "slave-dc1", node2Name)
-	}
-
-	node3Name := ""
-	fmt.Printf("check for PreferPrimary\n")
-	if row := c.QueryRowContext(NodeStateCriterion(tctx, hasql.PreferPrimary), "SELECT node_name as name"); row.Err() != nil {
-		t.Fatal(row.Err())
-	} else if err = row.Scan(&node3Name); err != nil {
-		t.Fatal(err)
-	} else if "master-dc1" != node3Name {
-		t.Fatalf("invalid node name %s != %s", "master-dc1", node3Name)
-	}
-
-	dbSlaveDC1Mock.ExpectQuery(`.*`).WillReturnRows(sqlmock.NewRows([]string{"role"}).RowError(1, fmt.Errorf("row error")))
-
-	time.Sleep(2 * time.Second)
-
-	fmt.Printf("check for PreferStandby\n")
-	if row := c.QueryRowContext(NodeStateCriterion(tctx, hasql.PreferStandby), "SELECT node_name as name"); row.Err() == nil {
-		t.Fatal("must return error")
-	}
-
-	if dbMasterErr := dbMasterMock.ExpectationsWereMet(); dbMasterErr != nil {
-		t.Error(dbMasterErr)
-	}
-}

codec/codec.go

@@ -3,8 +3,6 @@ package codec
 
 import (
 	"errors"
-
-	"gopkg.in/yaml.v3"
 )
 
 var (
@@ -68,10 +66,10 @@ func (m *RawMessage) MarshalYAML() ([]byte, error) {
 }
 
 // UnmarshalYAML sets *m to a copy of data.
-func (m *RawMessage) UnmarshalYAML(n *yaml.Node) error {
+func (m *RawMessage) UnmarshalYAML(data []byte) error {
 	if m == nil {
 		return errors.New("RawMessage UnmarshalYAML on nil pointer")
 	}
-	*m = append((*m)[0:0], []byte(n.Value)...)
+	*m = append((*m)[0:0], data...)
 	return nil
 }

codec/frame.go

@@ -1,7 +1,5 @@
 package codec
 
-import "gopkg.in/yaml.v3"
-
 // Frame gives us the ability to define raw data to send over the pipes
 type Frame struct {
 	Data []byte
@@ -28,8 +26,8 @@ func (m *Frame) MarshalYAML() ([]byte, error) {
 }
 
 // UnmarshalYAML set frame data
-func (m *Frame) UnmarshalYAML(n *yaml.Node) error {
-	m.Data = []byte(n.Value)
+func (m *Frame) UnmarshalYAML(data []byte) error {
+	m.Data = append((m.Data)[0:0], data...)
 	return nil
 }
 

codec/frame.proto

@@ -17,7 +17,7 @@ syntax = "proto3";
 package micro.codec;
 
 option cc_enable_arenas = true;
-option go_package = "go.unistack.org/micro/v3/codec;codec";
+option go_package = "go.unistack.org/micro/v4/codec;codec";
 option java_multiple_files = true;
 option java_outer_classname = "MicroCodec";
 option java_package = "micro.codec";

codec/noop.go

@@ -3,7 +3,7 @@ package codec
 import (
 	"encoding/json"
 
-	codecpb "go.unistack.org/micro-proto/v3/codec"
+	codecpb "go.unistack.org/micro-proto/v4/codec"
 )
 
 type noopCodec struct {

codec/options.go

@@ -3,9 +3,9 @@ package codec
 import (
 	"context"
 
-	"go.unistack.org/micro/v3/logger"
-	"go.unistack.org/micro/v3/meter"
-	"go.unistack.org/micro/v3/tracer"
+	"go.unistack.org/micro/v4/logger"
+	"go.unistack.org/micro/v4/meter"
+	"go.unistack.org/micro/v4/tracer"
 )
 
 // Option func

config/default.go

@@ -9,10 +9,10 @@ import (
 
 	"dario.cat/mergo"
 	"github.com/google/uuid"
-	"go.unistack.org/micro/v3/options"
-	mid "go.unistack.org/micro/v3/util/id"
-	rutil "go.unistack.org/micro/v3/util/reflect"
-	mtime "go.unistack.org/micro/v3/util/time"
+	"go.unistack.org/micro/v4/options"
+	mid "go.unistack.org/micro/v4/util/id"
+	rutil "go.unistack.org/micro/v4/util/reflect"
+	mtime "go.unistack.org/micro/v4/util/time"
 )
 
 type defaultConfig struct {
@@ -210,7 +210,7 @@ func fillValue(value reflect.Value, val string) error {
 				return err
 			}
 			value.Set(reflect.ValueOf(v))
-		case value.Type().String() == "time.Duration" && value.Type().PkgPath() == "go.unistack.org/micro/v3/util/time":
+		case value.Type().String() == "time.Duration" && value.Type().PkgPath() == "go.unistack.org/micro/v4/util/time":
 			v, err := mtime.ParseDuration(val)
 			if err != nil {
 				return err

config/default_test.go

@@ -7,8 +7,8 @@ import (
 	"testing"
 	"time"
 
-	"go.unistack.org/micro/v3/config"
-	mtime "go.unistack.org/micro/v3/util/time"
+	"go.unistack.org/micro/v4/config"
+	mtime "go.unistack.org/micro/v4/util/time"
 )
 
 type cfg struct {

config/options.go

@@ -4,11 +4,11 @@ import (
 	"context"
 	"time"
 
-	"go.unistack.org/micro/v3/codec"
-	"go.unistack.org/micro/v3/logger"
-	"go.unistack.org/micro/v3/meter"
-	"go.unistack.org/micro/v3/options"
-	"go.unistack.org/micro/v3/tracer"
+	"go.unistack.org/micro/v4/codec"
+	"go.unistack.org/micro/v4/logger"
+	"go.unistack.org/micro/v4/meter"
+	"go.unistack.org/micro/v4/options"
+	"go.unistack.org/micro/v4/tracer"
 )
 
 // Options hold the config options

errors/errors.proto

@@ -17,7 +17,7 @@ syntax = "proto3";
 package micro.errors;
 
 option cc_enable_arenas = true;
-option go_package = "go.unistack.org/micro/v3/errors;errors";
+option go_package = "go.unistack.org/micro/v4/errors;errors";
 option java_multiple_files = true;
 option java_outer_classname = "MicroErrors";
 option java_package = "micro.errors";

event.go

@@ -1,27 +0,0 @@
-package micro
-
-import (
-	"context"
-
-	"go.unistack.org/micro/v3/client"
-)
-
-// Event is used to publish messages to a topic
-type Event interface {
-	// Publish publishes a message to the event topic
-	Publish(ctx context.Context, msg interface{}, opts ...client.PublishOption) error
-}
-
-type event struct {
-	c     client.Client
-	topic string
-}
-
-// NewEvent creates a new event publisher
-func NewEvent(topic string, c client.Client) Event {
-	return &event{c, topic}
-}
-
-func (e *event) Publish(ctx context.Context, msg interface{}, opts ...client.PublishOption) error {
-	return e.c.Publish(ctx, e.c.NewMessage(e.topic, msg), opts...)
-}

flow/context.go

@@ -15,15 +15,6 @@ func FromContext(ctx context.Context) (Flow, bool) {
 	return c, ok
 }
 
-// MustContext returns Flow from context
-func MustContext(ctx context.Context) Flow {
-	f, ok := FromContext(ctx)
-	if !ok {
-		panic("missing flow")
-	}
-	return f
-}
-
 // NewContext stores Flow to context
 func NewContext(ctx context.Context, f Flow) context.Context {
 	if ctx == nil {

flow/context_test.go

@@ -1,3 +1,5 @@
+//go:build ignore
+
 package flow
 
 import (

flow/default.go

@@ -1,17 +1,19 @@
+//go:build ignore
+
 package flow
 
 import (
 	"context"
 	"fmt"
+	"path/filepath"
 	"sync"
 
-	"github.com/silas/dag"
-	"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"
+	"github.com/heimdalr/dag"
+	"go.unistack.org/micro/v4/client"
+	"go.unistack.org/micro/v4/codec"
+	"go.unistack.org/micro/v4/metadata"
+	"go.unistack.org/micro/v4/store"
+	"go.unistack.org/micro/v4/util/id"
 )
 
 type microFlow struct {
@@ -20,7 +22,7 @@ type microFlow struct {
 
 type microWorkflow struct {
 	opts   Options
-	g      *dag.AcyclicGraph
+	g      *dag.DAG
 	steps  map[string]Step
 	id     string
 	status Status
@@ -32,20 +34,20 @@ func (w *microWorkflow) ID() string {
 	return w.id
 }
 
-func (w *microWorkflow) Steps() ([][]Step, error) {
-	return w.getSteps("", false)
-}
-
 func (w *microWorkflow) Status() Status {
 	return w.status
 }
 
 func (w *microWorkflow) AppendSteps(steps ...Step) error {
+	var err error
 	w.Lock()
+	defer w.Unlock()
 
 	for _, s := range steps {
 		w.steps[s.String()] = s
-		w.g.Add(s)
+		if _, err = w.g.AddVertex(s); err != nil {
+			return err
+		}
 	}
 
 	for _, dst := range steps {
@@ -54,18 +56,13 @@ func (w *microWorkflow) AppendSteps(steps ...Step) error {
 			if !ok {
 				return ErrStepNotExists
 			}
-			w.g.Connect(dag.BasicEdge(src, dst))
+			if err = w.g.AddEdge(src.String(), dst.String()); err != nil {
+				return err
+			}
 		}
 	}
 
-	if err := w.g.Validate(); err != nil {
-		w.Unlock()
-		return err
-	}
-
-	w.g.TransitiveReduction()
-
-	w.Unlock()
+	w.g.ReduceTransitively()
 
 	return nil
 }
@@ -74,10 +71,11 @@ func (w *microWorkflow) RemoveSteps(steps ...Step) error {
 	// TODO: handle case when some step requires or required by removed step
 
 	w.Lock()
+	defer w.Unlock()
 
 	for _, s := range steps {
 		delete(w.steps, s.String())
-		w.g.Remove(s)
+		w.g.DeleteVertex(s.String())
 	}
 
 	for _, dst := range steps {
@@ -86,91 +84,34 @@ func (w *microWorkflow) RemoveSteps(steps ...Step) error {
 			if !ok {
 				return ErrStepNotExists
 			}
-			w.g.Connect(dag.BasicEdge(src, dst))
+			w.g.AddEdge(src.String(), dst.String())
 		}
 	}
 
-	if err := w.g.Validate(); err != nil {
-		w.Unlock()
-		return err
-	}
-
-	w.g.TransitiveReduction()
-
-	w.Unlock()
+	w.g.ReduceTransitively()
 
 	return nil
 }
 
-func (w *microWorkflow) getSteps(start string, reverse bool) ([][]Step, error) {
-	var steps [][]Step
-	var root dag.Vertex
-	var err error
-
-	fn := func(n dag.Vertex, idx int) error {
-		if idx == 0 {
-			steps = make([][]Step, 1)
-			steps[0] = make([]Step, 0, 1)
-		} else if idx >= len(steps) {
-			tsteps := make([][]Step, idx+1)
-			copy(tsteps, steps)
-			steps = tsteps
-			steps[idx] = make([]Step, 0, 1)
-		}
-		steps[idx] = append(steps[idx], n.(Step))
-		return nil
-	}
-
-	if start != "" {
-		var ok bool
-		w.RLock()
-		root, ok = w.steps[start]
-		w.RUnlock()
-		if !ok {
-			return nil, ErrStepNotExists
-		}
-	} else {
-		root, err = w.g.Root()
-		if err != nil {
-			return nil, err
-		}
-	}
-
-	if reverse {
-		err = w.g.SortedReverseDepthFirstWalk([]dag.Vertex{root}, fn)
-	} else {
-		err = w.g.SortedDepthFirstWalk([]dag.Vertex{root}, fn)
-	}
-	if err != nil {
-		return nil, err
-	}
-
-	return steps, nil
-}
-
 func (w *microWorkflow) Abort(ctx context.Context, id string) error {
-	workflowStore := store.NewNamespaceStore(w.opts.Store, "workflows"+w.opts.Store.Options().Separator+id)
+	workflowStore := store.NewNamespaceStore(w.opts.Store, filepath.Join("workflows", id))
 	return workflowStore.Write(ctx, "status", &codec.Frame{Data: []byte(StatusAborted.String())})
 }
 
 func (w *microWorkflow) Suspend(ctx context.Context, id string) error {
-	workflowStore := store.NewNamespaceStore(w.opts.Store, "workflows"+w.opts.Store.Options().Separator+id)
+	workflowStore := store.NewNamespaceStore(w.opts.Store, filepath.Join("workflows", id))
 	return workflowStore.Write(ctx, "status", &codec.Frame{Data: []byte(StatusSuspend.String())})
 }
 
 func (w *microWorkflow) Resume(ctx context.Context, id string) error {
-	workflowStore := store.NewNamespaceStore(w.opts.Store, "workflows"+w.opts.Store.Options().Separator+id)
+	workflowStore := store.NewNamespaceStore(w.opts.Store, filepath.Join("workflows", id))
 	return workflowStore.Write(ctx, "status", &codec.Frame{Data: []byte(StatusRunning.String())})
 }
 
 func (w *microWorkflow) Execute(ctx context.Context, req *Message, opts ...ExecuteOption) (string, error) {
 	w.Lock()
 	if !w.init {
-		if err := w.g.Validate(); err != nil {
-			w.Unlock()
-			return "", err
-		}
-		w.g.TransitiveReduction()
+		w.g.ReduceTransitively()
 		w.init = true
 	}
 	w.Unlock()
@@ -180,26 +121,11 @@ func (w *microWorkflow) Execute(ctx context.Context, req *Message, opts ...Execu
 		return "", err
 	}
 
-	stepStore := store.NewNamespaceStore(w.opts.Store, "steps"+w.opts.Store.Options().Separator+eid)
-	workflowStore := store.NewNamespaceStore(w.opts.Store, "workflows"+w.opts.Store.Options().Separator+eid)
+	//	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.Error(w.opts.Context, "store write error", werr)
-		}
-		return "", err
-	}
-
-	var wg sync.WaitGroup
-	cherr := make(chan error, 1)
-	chstatus := make(chan Status, 1)
-
-	nctx, cancel := context.WithCancel(ctx)
-	defer cancel()
-
 	nopts := make([]ExecuteOption, 0, len(opts)+5)
 
 	nopts = append(nopts,
@@ -209,143 +135,274 @@ func (w *microWorkflow) Execute(ctx context.Context, req *Message, opts ...Execu
 		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.Error(w.opts.Context, "store write error", werr)
+	if werr := workflowStore.Write(ctx, "status", &codec.Frame{Data: []byte(StatusRunning.String())}); werr != nil {
+		w.opts.Logger.Error(ctx, "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, cstep.ID()+w.opts.Store.Options().Separator+"status", &codec.Frame{Data: []byte(StatusPending.String())}); werr != nil {
-				return eid, werr
+
+	var startID string
+	if options.Start == "" {
+		mp := w.g.GetRoots()
+		if len(mp) != 1 {
+			return eid, ErrStepNotExists
+		}
+		for k := range mp {
+			startID = k
+		}
+	} else {
+		for k, v := range w.g.GetVertices() {
+			if v == options.Start {
+				startID = k
 			}
 		}
 	}
 
-	go func() {
-		for idx := range steps {
-			for nidx := range steps[idx] {
-				wStatus := &codec.Frame{}
-				if werr := workflowStore.Read(w.opts.Context, "status", wStatus); werr != nil {
-					cherr <- werr
-					return
+	if startID == "" {
+		return eid, ErrStepNotExists
+	}
+
+	if options.Async {
+		go w.handleWorkflow(startID, nopts...)
+		return eid, nil
+	}
+
+	return eid, w.handleWorkflow(startID, nopts...)
+}
+
+func (w *microWorkflow) handleWorkflow(startID string, opts ...ExecuteOption) error {
+	w.RLock()
+	defer w.RUnlock()
+
+	//	stepStore := store.NewNamespaceStore(w.opts.Store, filepath.Join("steps", eid))
+	// workflowStore := store.NewNamespaceStore(w.opts.Store, filepath.Join("workflows", eid))
+
+	// Get IDs of all descendant vertices.
+	flowIDs, errDes := w.g.GetDescendants(startID)
+	if errDes != nil {
+		return errDes
+	}
+
+	// inputChannels provides for input channels for each of the descendant vertices (+ the start-vertex).
+	inputChannels := make(map[string]chan FlowResult, len(flowIDs)+1)
+
+	// Iterate vertex IDs and create an input channel for each of them and a single
+	// output channel for leaves. Note, this "pre-flight" is needed to ensure we
+	// really have an input channel regardless of how we traverse the tree and spawn
+	// workers.
+	leafCount := 0
+
+	for id := range flowIDs {
+
+		// Get all parents of this vertex.
+		parents, errPar := w.g.GetParents(id)
+		if errPar != nil {
+			return errPar
+		}
+
+		// Create a buffered input channel that has capacity for all parent results.
+		inputChannels[id] = make(chan FlowResult, len(parents))
+
+		if ok, err := w.g.IsLeaf(id); ok && err == nil {
+			leafCount += 1
+		}
+	}
+
+	// outputChannel caries the results of leaf vertices.
+	outputChannel := make(chan FlowResult, leafCount)
+
+	// To also process the start vertex and to have its results being passed to its
+	// children, add it to the vertex IDs. Also add an input channel for the start
+	// vertex and feed the inputs to this channel.
+	flowIDs[startID] = struct{}{}
+	inputChannels[startID] = make(chan FlowResult, len(inputs))
+	for _, i := range inputs {
+		inputChannels[startID] <- i
+	}
+
+	wg := sync.WaitGroup{}
+
+	// Iterate all vertex IDs (now incl. start vertex) and handle each worker (incl.
+	// inputs and outputs) in a separate goroutine.
+	for id := range flowIDs {
+
+		// Get all children of this vertex that later need to be notified. Note, we
+		// collect all children before the goroutine to be able to release the read
+		// lock as early as possible.
+		children, errChildren := w.g.GetChildren(id)
+		if errChildren != nil {
+			return errChildren
+		}
+
+		// Remember to wait for this goroutine.
+		wg.Add(1)
+
+		go func(id string) {
+			// Get this vertex's input channel.
+			// Note, only concurrent read here, which is fine.
+			c := inputChannels[id]
+
+			// Await all parent inputs and stuff them into a slice.
+			parentCount := cap(c)
+			parentResults := make([]FlowResult, parentCount)
+			for i := 0; i < parentCount; i++ {
+				parentResults[i] = <-c
+			}
+
+			// Execute the worker.
+			errWorker := callback(w.g, id, parentResults)
+			if errWorker != nil {
+				return errWorker
+			}
+
+			// Send this worker's FlowResult onto all children's input channels or, if it is
+			// a leaf (i.e. no children), send the result onto the output channel.
+			if len(children) > 0 {
+				for child := range children {
+					inputChannels[child] <- flowResult
 				}
-				if status := StringStatus[string(wStatus.Data)]; status != StatusRunning {
-					chstatus <- status
-					return
-				}
-				if w.opts.Logger.V(logger.TraceLevel) {
-					w.opts.Logger.Trace(nctx, fmt.Sprintf("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, step.ID()+w.opts.Store.Options().Separator+"req", req); werr != nil {
-							cherr <- werr
-							return
-						}
-						if werr := stepStore.Write(ctx, step.ID()+w.opts.Store.Options().Separator+"status", &codec.Frame{Data: []byte(StatusRunning.String())}); werr != nil {
-							cherr <- werr
-							return
-						}
-						rsp, serr := step.Execute(nctx, req, nopts...)
-						if serr != nil {
-							step.SetStatus(StatusFailure)
-							if werr := stepStore.Write(ctx, step.ID()+w.opts.Store.Options().Separator+"rsp", serr); werr != nil && w.opts.Logger.V(logger.ErrorLevel) {
-								w.opts.Logger.Error(ctx, "store write error", werr)
+			} else {
+				outputChannel <- flowResult
+			}
+
+			// "Sign off".
+			wg.Done()
+		}(id)
+	}
+
+	// Wait for all go routines to finish.
+	wg.Wait()
+
+	// Await all leaf vertex results and stuff them into a slice.
+	resultCount := cap(outputChannel)
+	results := make([]FlowResult, resultCount)
+	for i := 0; i < resultCount; i++ {
+		results[i] = <-outputChannel
+	}
+
+	/*
+		go func() {
+			for idx := range steps {
+				for nidx := range steps[idx] {
+					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, step.ID()+w.opts.Store.Options().Separator+"status", &codec.Frame{Data: []byte(StatusFailure.String())}); werr != nil && w.opts.Logger.V(logger.ErrorLevel) {
-								w.opts.Logger.Error(ctx, "store write error", werr)
+							if werr := stepStore.Write(ctx, filepath.Join(step.ID(), "status"), &codec.Frame{Data: []byte(StatusRunning.String())}); werr != nil {
+								cherr <- werr
+								return
+							}
+							rsp, serr := step.Execute(nctx, req, nopts...)
+							if serr != nil {
+								step.SetStatus(StatusFailure)
+								if werr := stepStore.Write(ctx, filepath.Join(step.ID(), "rsp"), serr); werr != nil && w.opts.Logger.V(logger.ErrorLevel) {
+									w.opts.Logger.Errorf(ctx, "store write error: %v", werr)
+								}
+								if werr := stepStore.Write(ctx, filepath.Join(step.ID(), "status"), &codec.Frame{Data: []byte(StatusFailure.String())}); werr != nil && w.opts.Logger.V(logger.ErrorLevel) {
+									w.opts.Logger.Errorf(ctx, "store write error: %v", werr)
+								}
+								cherr <- serr
+								return
+							}
+							if werr := stepStore.Write(ctx, filepath.Join(step.ID(), "rsp"), rsp); werr != nil {
+								w.opts.Logger.Errorf(ctx, "store write error: %v", werr)
+								cherr <- werr
+								return
+							}
+							if werr := stepStore.Write(ctx, filepath.Join(step.ID(), "status"), &codec.Frame{Data: []byte(StatusSuccess.String())}); werr != nil {
+								w.opts.Logger.Errorf(ctx, "store write error: %v", werr)
+								cherr <- werr
+								return
+							}
+						}(cstep)
+						wg.Wait()
+					} else {
+						if werr := stepStore.Write(ctx, filepath.Join(cstep.ID(), "req"), req); werr != nil {
+							cherr <- werr
+							return
+						}
+						if werr := stepStore.Write(ctx, filepath.Join(cstep.ID(), "status"), &codec.Frame{Data: []byte(StatusRunning.String())}); werr != nil {
+							cherr <- werr
+							return
+						}
+						rsp, serr := cstep.Execute(nctx, req, nopts...)
+						if serr != nil {
+							cstep.SetStatus(StatusFailure)
+							if werr := stepStore.Write(ctx, filepath.Join(cstep.ID(), "rsp"), serr); werr != nil && w.opts.Logger.V(logger.ErrorLevel) {
+								w.opts.Logger.Errorf(ctx, "store write error: %v", werr)
+							}
+							if werr := stepStore.Write(ctx, filepath.Join(cstep.ID(), "status"), &codec.Frame{Data: []byte(StatusFailure.String())}); werr != nil && w.opts.Logger.V(logger.ErrorLevel) {
+								w.opts.Logger.Errorf(ctx, "store write error: %v", werr)
 							}
 							cherr <- serr
 							return
 						}
-						if werr := stepStore.Write(ctx, step.ID()+w.opts.Store.Options().Separator+"rsp", rsp); werr != nil {
-							w.opts.Logger.Error(ctx, "store write error", werr)
+						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, step.ID()+w.opts.Store.Options().Separator+"status", &codec.Frame{Data: []byte(StatusSuccess.String())}); werr != nil {
-							w.opts.Logger.Error(ctx, "store write error", werr)
+						if werr := stepStore.Write(ctx, filepath.Join(cstep.ID(), "status"), &codec.Frame{Data: []byte(StatusSuccess.String())}); werr != nil {
 							cherr <- werr
 							return
 						}
-					}(cstep)
-					wg.Wait()
-				} else {
-					if werr := stepStore.Write(ctx, cstep.ID()+w.opts.Store.Options().Separator+"req", req); werr != nil {
-						cherr <- werr
-						return
-					}
-					if werr := stepStore.Write(ctx, cstep.ID()+w.opts.Store.Options().Separator+"status", &codec.Frame{Data: []byte(StatusRunning.String())}); werr != nil {
-						cherr <- werr
-						return
-					}
-					rsp, serr := cstep.Execute(nctx, req, nopts...)
-					if serr != nil {
-						cstep.SetStatus(StatusFailure)
-						if werr := stepStore.Write(ctx, cstep.ID()+w.opts.Store.Options().Separator+"rsp", serr); werr != nil && w.opts.Logger.V(logger.ErrorLevel) {
-							w.opts.Logger.Error(ctx, "store write error", werr)
-						}
-						if werr := stepStore.Write(ctx, cstep.ID()+w.opts.Store.Options().Separator+"status", &codec.Frame{Data: []byte(StatusFailure.String())}); werr != nil && w.opts.Logger.V(logger.ErrorLevel) {
-							w.opts.Logger.Error(ctx, "store write error", werr)
-						}
-						cherr <- serr
-						return
-					}
-					if werr := stepStore.Write(ctx, cstep.ID()+w.opts.Store.Options().Separator+"rsp", rsp); werr != nil {
-						w.opts.Logger.Error(ctx, "store write error", werr)
-						cherr <- werr
-						return
-					}
-					if werr := stepStore.Write(ctx, cstep.ID()+w.opts.Store.Options().Separator+"status", &codec.Frame{Data: []byte(StatusSuccess.String())}); werr != nil {
-						cherr <- werr
-						return
 					}
 				}
 			}
-		}
-		close(done)
-	}()
+			close(done)
+		}()
 
-	if options.Async {
-		return eid, nil
-	}
-
-	logger.DefaultLogger.Trace(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.Error(w.opts.Context, "store write error", werr)
+		if options.Async {
+			return eid, nil
 		}
-	case err == nil:
-		if werr := workflowStore.Write(w.opts.Context, "status", &codec.Frame{Data: []byte(StatusSuccess.String())}); werr != nil {
-			w.opts.Logger.Error(w.opts.Context, "store write error", werr)
-		}
-	case err != nil:
-		if werr := workflowStore.Write(w.opts.Context, "status", &codec.Frame{Data: []byte(StatusFailure.String())}); werr != nil {
-			w.opts.Logger.Error(w.opts.Context, "store write error", werr)
-		}
-	}
 
-	return eid, 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 err
 }
 
 // NewFlow create new flow
@@ -385,11 +442,11 @@ func (f *microFlow) WorkflowList(ctx context.Context) ([]Workflow, error) {
 }
 
 func (f *microFlow) WorkflowCreate(ctx context.Context, id string, steps ...Step) (Workflow, error) {
-	w := &microWorkflow{opts: f.opts, id: id, g: &dag.AcyclicGraph{}, steps: make(map[string]Step, len(steps))}
+	w := &microWorkflow{opts: f.opts, id: id, g: &dag.DAG{}, steps: make(map[string]Step, len(steps))}
 
 	for _, s := range steps {
 		w.steps[s.String()] = s
-		w.g.Add(s)
+		w.g.AddVertex(s)
 	}
 
 	for _, dst := range steps {
@@ -398,14 +455,11 @@ func (f *microFlow) WorkflowCreate(ctx context.Context, id string, steps ...Step
 			if !ok {
 				return nil, ErrStepNotExists
 			}
-			w.g.Connect(dag.BasicEdge(src, dst))
+			w.g.AddEdge(src.String(), dst.String())
 		}
 	}
 
-	if err := w.g.Validate(); err != nil {
-		return nil, err
-	}
-	w.g.TransitiveReduction()
+	w.g.ReduceTransitively()
 
 	w.init = true
 

flow/flow.go

@@ -1,5 +1,5 @@
 // Package flow is an interface used for saga pattern microservice workflow
-package flow
+package flow // import "go.unistack.org/micro/v4/flow"
 
 import (
 	"context"
@@ -7,7 +7,7 @@ import (
 	"sync"
 	"sync/atomic"
 
-	"go.unistack.org/micro/v3/metadata"
+	"go.unistack.org/micro/v4/metadata"
 )
 
 var (
@@ -125,8 +125,6 @@ type Workflow interface {
 	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

flow/options.go

@@ -4,11 +4,11 @@ import (
 	"context"
 	"time"
 
-	"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"
+	"go.unistack.org/micro/v4/client"
+	"go.unistack.org/micro/v4/logger"
+	"go.unistack.org/micro/v4/meter"
+	"go.unistack.org/micro/v4/store"
+	"go.unistack.org/micro/v4/tracer"
 )
 
 // Option func
@@ -123,8 +123,6 @@ type ExecuteOptions struct {
 	Start string
 	// Timeout for execution
 	Timeout time.Duration
-	// Reverse execution
-	Reverse bool
 	// Async enables async execution
 	Async bool
 }
@@ -167,13 +165,6 @@ func ExecuteContext(ctx context.Context) ExecuteOption {
 	}
 }
 
-// ExecuteReverse says that dag must be run in reverse order
-func ExecuteReverse(b bool) ExecuteOption {
-	return func(o *ExecuteOptions) {
-		o.Reverse = b
-	}
-}
-
 // ExecuteTimeout pass timeout time.Duration for execution
 func ExecuteTimeout(td time.Duration) ExecuteOption {
 	return func(o *ExecuteOptions) {

fsm/fsm_test.go

@@ -5,7 +5,7 @@ import (
 	"fmt"
 	"testing"
 
-	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v4/logger"
 )
 
 func TestFSMStart(t *testing.T) {

go.mod

@@ -1,44 +1,35 @@
-module go.unistack.org/micro/v3
+module go.unistack.org/micro/v4
 
-go 1.24.0
+go 1.24
 
 require (
 	dario.cat/mergo v1.0.1
 	github.com/DATA-DOG/go-sqlmock v1.5.2
-	github.com/KimMachineGun/automemlimit v0.6.1
-	github.com/ash3in/uuidv8 v1.2.0
+	github.com/KimMachineGun/automemlimit v0.7.0
+	github.com/goccy/go-yaml v1.17.1
 	github.com/google/uuid v1.6.0
 	github.com/matoous/go-nanoid v1.5.1
 	github.com/patrickmn/go-cache v2.1.0+incompatible
 	github.com/silas/dag v0.0.0-20220518035006-a7e85ada93c5
+	github.com/spf13/cast v1.7.1
 	github.com/stretchr/testify v1.10.0
+	go.uber.org/atomic v1.11.0
 	go.uber.org/automaxprocs v1.6.0
-	go.unistack.org/micro-proto/v3 v3.4.1
+	go.unistack.org/micro-proto/v4 v4.1.0
 	golang.org/x/sync v0.10.0
 	golang.yandex/hasql/v2 v2.1.0
-	google.golang.org/grpc v1.69.2
-	google.golang.org/protobuf v1.36.1
-	gopkg.in/yaml.v3 v3.0.1
+	google.golang.org/grpc v1.69.4
+	google.golang.org/protobuf v1.36.3
 )
 
 require (
-	github.com/cilium/ebpf v0.16.0 // indirect
-	github.com/containerd/cgroups/v3 v3.0.4 // indirect
-	github.com/containerd/log v0.1.0 // indirect
-	github.com/coreos/go-systemd/v22 v22.5.0 // indirect
 	github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc // indirect
-	github.com/docker/go-units v0.5.0 // indirect
-	github.com/godbus/dbus/v5 v5.1.0 // indirect
-	github.com/moby/sys/userns v0.1.0 // indirect
-	github.com/opencontainers/runtime-spec v1.2.0 // indirect
 	github.com/pbnjay/memory v0.0.0-20210728143218-7b4eea64cf58 // indirect
 	github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2 // indirect
 	github.com/rogpeppe/go-internal v1.13.1 // indirect
-	github.com/sirupsen/logrus v1.9.3 // indirect
-	go.uber.org/goleak v1.3.0 // indirect
-	golang.org/x/exp v0.0.0-20241210194714-1829a127f884 // indirect
-	golang.org/x/net v0.33.0 // indirect
-	golang.org/x/sys v0.28.0 // indirect
+	golang.org/x/net v0.34.0 // indirect
+	golang.org/x/sys v0.29.0 // indirect
 	google.golang.org/genproto/googleapis/rpc v0.0.0-20241216192217-9240e9c98484 // indirect
 	gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
 )

go.sum

@@ -2,39 +2,20 @@ dario.cat/mergo v1.0.1 h1:Ra4+bf83h2ztPIQYNP99R6m+Y7KfnARDfID+a+vLl4s=
 dario.cat/mergo v1.0.1/go.mod h1:uNxQE+84aUszobStD9th8a29P2fMDhsBdgRYvZOxGmk=
 github.com/DATA-DOG/go-sqlmock v1.5.2 h1:OcvFkGmslmlZibjAjaHm3L//6LiuBgolP7OputlJIzU=
 github.com/DATA-DOG/go-sqlmock v1.5.2/go.mod h1:88MAG/4G7SMwSE3CeA0ZKzrT5CiOU3OJ+JlNzwDqpNU=
-github.com/KimMachineGun/automemlimit v0.6.1 h1:ILa9j1onAAMadBsyyUJv5cack8Y1WT26yLj/V+ulKp8=
-github.com/KimMachineGun/automemlimit v0.6.1/go.mod h1:T7xYht7B8r6AG/AqFcUdc7fzd2bIdBKmepfP2S1svPY=
-github.com/ash3in/uuidv8 v1.2.0 h1:2oogGdtCPwaVtyvPPGin4TfZLtOGE5F+W++E880G6SI=
-github.com/ash3in/uuidv8 v1.2.0/go.mod h1:BnU0wJBxnzdEKmVg4xckBkD+VZuecTFTUP3M0dWgyY4=
-github.com/cilium/ebpf v0.16.0 h1:+BiEnHL6Z7lXnlGUsXQPPAE7+kenAd4ES8MQ5min0Ok=
-github.com/cilium/ebpf v0.16.0/go.mod h1:L7u2Blt2jMM/vLAVgjxluxtBKlz3/GWjB0dMOEngfwE=
-github.com/containerd/cgroups/v3 v3.0.4 h1:2fs7l3P0Qxb1nKWuJNFiwhp2CqiKzho71DQkDrHJIo4=
-github.com/containerd/cgroups/v3 v3.0.4/go.mod h1:SA5DLYnXO8pTGYiAHXz94qvLQTKfVM5GEVisn4jpins=
-github.com/containerd/log v0.1.0 h1:TCJt7ioM2cr/tfR8GPbGf9/VRAX8D2B4PjzCpfX540I=
-github.com/containerd/log v0.1.0/go.mod h1:VRRf09a7mHDIRezVKTRCrOq78v577GXq3bSa3EhrzVo=
-github.com/coreos/go-systemd/v22 v22.5.0 h1:RrqgGjYQKalulkV8NGVIfkXQf6YYmOyiJKk8iXXhfZs=
-github.com/coreos/go-systemd/v22 v22.5.0/go.mod h1:Y58oyj3AT4RCenI/lSvhwexgC+NSVTIJ3seZv2GcEnc=
-github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
-github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/KimMachineGun/automemlimit v0.7.0 h1:7G06p/dMSf7G8E6oq+f2uOPuVncFyIlDI/pBWK49u88=
+github.com/KimMachineGun/automemlimit v0.7.0/go.mod h1:QZxpHaGOQoYvFhv/r4u3U0JTC2ZcOwbSr11UZF46UBM=
 github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc h1:U9qPSI2PIWSS1VwoXQT9A3Wy9MM3WgvqSxFWenqJduM=
 github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
-github.com/docker/go-units v0.5.0 h1:69rxXcBk27SvSaaxTtLh/8llcHD8vYHT7WSdRZ/jvr4=
-github.com/docker/go-units v0.5.0/go.mod h1:fgPhTUdO+D/Jk86RDLlptpiXQzgHJF7gydDDbaIK4Dk=
-github.com/go-quicktest/qt v1.101.0 h1:O1K29Txy5P2OK0dGo59b7b0LR6wKfIhttaAhHUyn7eI=
-github.com/go-quicktest/qt v1.101.0/go.mod h1:14Bz/f7NwaXPtdYEgzsx46kqSxVwTbzVZsDC26tQJow=
-github.com/godbus/dbus/v5 v5.0.4/go.mod h1:xhWf0FNVPg57R7Z0UbKHbJfkEywrmjJnf7w5xrFpKfA=
-github.com/godbus/dbus/v5 v5.1.0 h1:4KLkAxT3aOY8Li4FRJe/KvhoNFFxo0m6fNuFUO8QJUk=
-github.com/godbus/dbus/v5 v5.1.0/go.mod h1:xhWf0FNVPg57R7Z0UbKHbJfkEywrmjJnf7w5xrFpKfA=
+github.com/frankban/quicktest v1.14.6 h1:7Xjx+VpznH+oBnejlPUj8oUpdxnVs4f8XU8WnHkI4W8=
+github.com/frankban/quicktest v1.14.6/go.mod h1:4ptaffx2x8+WTWXmUCuVU6aPUX1/Mz7zb5vbUoiM6w0=
+github.com/goccy/go-yaml v1.17.1 h1:LI34wktB2xEE3ONG/2Ar54+/HJVBriAGJ55PHls4YuY=
+github.com/goccy/go-yaml v1.17.1/go.mod h1:XBurs7gK8ATbW4ZPGKgcbrY1Br56PdM69F7LkFRi1kA=
 github.com/golang/protobuf v1.5.4 h1:i7eJL8qZTpSEXOPTxNKhASYpMn+8e5Q6AdndVa1dWek=
 github.com/golang/protobuf v1.5.4/go.mod h1:lnTiLA8Wa4RWRcIUkrtSVa5nRhsEGBg48fD6rSs7xps=
 github.com/google/go-cmp v0.6.0 h1:ofyhxvXcZhMsU5ulbFiLKl/XBFqE1GSq7atu8tAmTRI=
 github.com/google/go-cmp v0.6.0/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
 github.com/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
 github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
-github.com/josharian/native v1.1.0 h1:uuaP0hAbW7Y4l0ZRQ6C9zfb7Mg1mbFKry/xzDAfmtLA=
-github.com/josharian/native v1.1.0/go.mod h1:7X/raswPFr05uY3HiLlYeyQntB6OO7E/d2Cu7qoaN2w=
-github.com/jsimonetti/rtnetlink/v2 v2.0.1 h1:xda7qaHDSVOsADNouv7ukSuicKZO7GgVUCXxpaIEIlM=
-github.com/jsimonetti/rtnetlink/v2 v2.0.1/go.mod h1:7MoNYNbb3UaDHtF8udiJo/RH6VsTKP1pqKLUTVCvToE=
 github.com/kisielk/sqlstruct v0.0.0-20201105191214-5f3e10d3ab46/go.mod h1:yyMNCyc/Ib3bDTKd379tNMpB/7/H5TjM2Y9QJ5THLbE=
 github.com/kr/pretty v0.2.1/go.mod h1:ipq/a2n7PKx3OHsz4KJII5eveXtPO4qwEXGdVfWzfnI=
 github.com/kr/pretty v0.3.1 h1:flRD4NNwYAUpkphVc1HcthR4KEIFJ65n8Mw5qdRn3LE=
@@ -45,19 +26,10 @@ github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY=
 github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE=
 github.com/matoous/go-nanoid v1.5.1 h1:aCjdvTyO9LLnTIi0fgdXhOPPvOHjpXN6Ik9DaNjIct4=
 github.com/matoous/go-nanoid v1.5.1/go.mod h1:zyD2a71IubI24efhpvkJz+ZwfwagzgSO6UNiFsZKN7U=
-github.com/mdlayher/netlink v1.7.2 h1:/UtM3ofJap7Vl4QWCPDGXY8d3GIY2UGSDbK+QWmY8/g=
-github.com/mdlayher/netlink v1.7.2/go.mod h1:xraEF7uJbxLhc5fpHL4cPe221LI2bdttWlU+ZGLfQSw=
-github.com/mdlayher/socket v0.4.1 h1:eM9y2/jlbs1M615oshPQOHZzj6R6wMT7bX5NPiQvn2U=
-github.com/mdlayher/socket v0.4.1/go.mod h1:cAqeGjoufqdxWkD7DkpyS+wcefOtmu5OQ8KuoJGIReA=
-github.com/moby/sys/userns v0.1.0 h1:tVLXkFOxVu9A64/yh59slHVv9ahO9UIev4JZusOLG/g=
-github.com/moby/sys/userns v0.1.0/go.mod h1:IHUYgu/kao6N8YZlp9Cf444ySSvCmDlmzUcYfDHOl28=
-github.com/opencontainers/runtime-spec v1.2.0 h1:z97+pHb3uELt/yiAWD691HNHQIF07bE7dzrbT927iTk=
-github.com/opencontainers/runtime-spec v1.2.0/go.mod h1:jwyrGlmzljRJv/Fgzds9SsS/C5hL+LL3ko9hs6T5lQ0=
 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/pbnjay/memory v0.0.0-20210728143218-7b4eea64cf58 h1:onHthvaw9LFnH4t2DcNVpwGmV9E1BkGknEliJkfwQj0=
 github.com/pbnjay/memory v0.0.0-20210728143218-7b4eea64cf58/go.mod h1:DXv8WO4yhMYhSNPKjeNKa5WY9YCIEBRbNzFFPJbWO6Y=
-github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2 h1:Jamvg5psRIccs7FGNTlIRMkT8wgtp5eCXdBlqhYGL6U=
 github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/prashantv/gostub v1.1.0 h1:BTyx3RfQjRHnUWaGF9oQos79AlQ5k8WNktv7VGvVH4g=
@@ -66,40 +38,34 @@ github.com/rogpeppe/go-internal v1.13.1 h1:KvO1DLK/DRN07sQ1LQKScxyZJuNnedQ5/wKSR
 github.com/rogpeppe/go-internal v1.13.1/go.mod h1:uMEvuHeurkdAXX61udpOXGD/AzZDWNMNyH2VO9fmH0o=
 github.com/silas/dag v0.0.0-20220518035006-a7e85ada93c5 h1:G/FZtUu7a6NTWl3KUHMV9jkLAh/Rvtf03NWMHaEDl+E=
 github.com/silas/dag v0.0.0-20220518035006-a7e85ada93c5/go.mod h1:7RTUFBdIRC9nZ7/3RyRNH1bdqIShrDejd1YbLwgPS+I=
-github.com/sirupsen/logrus v1.9.3 h1:dueUQJ1C2q9oE3F7wvmSGAaVtTmUizReu6fjN8uqzbQ=
-github.com/sirupsen/logrus v1.9.3/go.mod h1:naHLuLoDiP4jHNo9R0sCBMtWGeIprob74mVsIT4qYEQ=
-github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
-github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+github.com/spf13/cast v1.7.1 h1:cuNEagBQEHWN1FnbGEjCXL2szYEXqfJPbP2HNUaca9Y=
+github.com/spf13/cast v1.7.1/go.mod h1:ancEpBxwJDODSW/UG4rDrAqiKolqNNh2DX3mk86cAdo=
 github.com/stretchr/testify v1.10.0 h1:Xv5erBjTwe/5IxqUQTdXv5kgmIvbHo3QQyRwhJsOfJA=
 github.com/stretchr/testify v1.10.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=
+go.uber.org/atomic v1.11.0 h1:ZvwS0R+56ePWxUNi+Atn9dWONBPp/AUETXlHW0DxSjE=
+go.uber.org/atomic v1.11.0/go.mod h1:LUxbIzbOniOlMKjJjyPfpl4v+PKK2cNJn91OQbhoJI0=
 go.uber.org/automaxprocs v1.6.0 h1:O3y2/QNTOdbF+e/dpXNNW7Rx2hZ4sTIPyybbxyNqTUs=
 go.uber.org/automaxprocs v1.6.0/go.mod h1:ifeIMSnPZuznNm6jmdzmU3/bfk01Fe2fotchwEFJ8r8=
-go.uber.org/goleak v1.3.0 h1:2K3zAYmnTNqV73imy9J1T3WC+gmCePx2hEGkimedGto=
-go.uber.org/goleak v1.3.0/go.mod h1:CoHD4mav9JJNrW/WLlf7HGZPjdw8EucARQHekz1X6bE=
-go.unistack.org/micro-proto/v3 v3.4.1 h1:UTjLSRz2YZuaHk9iSlVqqsA50JQNAEK2ZFboGqtEa9Q=
-go.unistack.org/micro-proto/v3 v3.4.1/go.mod h1:okx/cnOhzuCX0ggl/vToatbCupi0O44diiiLLsZ93Zo=
-golang.org/x/exp v0.0.0-20241210194714-1829a127f884 h1:Y/Mj/94zIQQGHVSv1tTtQBDaQaJe62U9bkDZKKyhPCU=
-golang.org/x/exp v0.0.0-20241210194714-1829a127f884/go.mod h1:qj5a5QZpwLU2NLQudwIN5koi3beDhSAlJwa67PuM98c=
-golang.org/x/net v0.33.0 h1:74SYHlV8BIgHIFC/LrYkOGIwL19eTYXQ5wc6TBuO36I=
-golang.org/x/net v0.33.0/go.mod h1:HXLR5J+9DxmrqMwG9qjGCxZ+zKXxBru04zlTvWlWuN4=
+go.unistack.org/micro-proto/v4 v4.1.0 h1:qPwL2n/oqh9RE3RTTDgt28XK3QzV597VugQPaw9lKUk=
+go.unistack.org/micro-proto/v4 v4.1.0/go.mod h1:ArmK7o+uFvxSY3dbJhKBBX4Pm1rhWdLEFf3LxBrMtec=
+golang.org/x/net v0.34.0 h1:Mb7Mrk043xzHgnRM88suvJFwzVrRfHEHJEl5/71CKw0=
+golang.org/x/net v0.34.0/go.mod h1:di0qlW3YNM5oh6GqDGQr92MyTozJPmybPK4Ev/Gm31k=
 golang.org/x/sync v0.10.0 h1:3NQrjDixjgGwUOCaF8w2+VYHv0Ve/vGYSbdkTa98gmQ=
 golang.org/x/sync v0.10.0/go.mod h1:Czt+wKu1gCyEFDUtn0jG5QVvpJ6rzVqr5aXyt9drQfk=
-golang.org/x/sys v0.0.0-20220715151400-c0bba94af5f8/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.28.0 h1:Fksou7UEQUWlKvIdsqzJmUmCX3cZuD2+P3XyyzwMhlA=
-golang.org/x/sys v0.28.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
+golang.org/x/sys v0.29.0 h1:TPYlXGxvx1MGTn2GiZDhnjPA9wZzZeGKHHmKhHYvgaU=
+golang.org/x/sys v0.29.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
 golang.org/x/text v0.21.0 h1:zyQAAkrwaneQ066sspRyJaG9VNi/YJ1NfzcGB3hZ/qo=
 golang.org/x/text v0.21.0/go.mod h1:4IBbMaMmOPCJ8SecivzSH54+73PCFmPWxNTLm+vZkEQ=
 golang.yandex/hasql/v2 v2.1.0 h1:7CaFFWeHoK5TvA+QvZzlKHlIN5sqNpqM8NSrXskZD/k=
 golang.yandex/hasql/v2 v2.1.0/go.mod h1:3Au1AxuJDCTXmS117BpbI6e+70kGWeyLR1qJAH6HdtA=
 google.golang.org/genproto/googleapis/rpc v0.0.0-20241216192217-9240e9c98484 h1:Z7FRVJPSMaHQxD0uXU8WdgFh8PseLM8Q8NzhnpMrBhQ=
 google.golang.org/genproto/googleapis/rpc v0.0.0-20241216192217-9240e9c98484/go.mod h1:lcTa1sDdWEIHMWlITnIczmw5w60CF9ffkb8Z+DVmmjA=
-google.golang.org/grpc v1.69.2 h1:U3S9QEtbXC0bYNvRtcoklF3xGtLViumSYxWykJS+7AU=
-google.golang.org/grpc v1.69.2/go.mod h1:vyjdE6jLBI76dgpDojsFGNaHlxdjXN9ghpnd2o7JGZ4=
-google.golang.org/protobuf v1.36.1 h1:yBPeRvTftaleIgM3PZ/WBIZ7XM/eEYAaEyCwvyjq/gk=
-google.golang.org/protobuf v1.36.1/go.mod h1:9fA7Ob0pmnwhb644+1+CVWFRbNajQ6iRojtC/QF5bRE=
+google.golang.org/grpc v1.69.4 h1:MF5TftSMkd8GLw/m0KM6V8CMOCY6NZ1NQDPGFgbTt4A=
+google.golang.org/grpc v1.69.4/go.mod h1:vyjdE6jLBI76dgpDojsFGNaHlxdjXN9ghpnd2o7JGZ4=
+google.golang.org/protobuf v1.36.3 h1:82DV7MYdb8anAVi3qge1wSnMDrnKK7ebr+I0hHRN1BU=
+google.golang.org/protobuf v1.36.3/go.mod h1:9fA7Ob0pmnwhb644+1+CVWFRbNajQ6iRojtC/QF5bRE=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c h1:Hei/4ADfdWqJk1ZMxUNpqntNwaWcugrBjAiHlqqRiVk=
 gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c/go.mod h1:JHkPIbrfpd72SG/EVd6muEfDQjcINNoR0C8j2r3qZ4Q=
-gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
 gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
 gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

hooks/metadata/metadata.go

@@ -3,74 +3,115 @@ package metadata
 import (
 	"context"
 
-	"go.unistack.org/micro/v3/client"
-	"go.unistack.org/micro/v3/metadata"
-	"go.unistack.org/micro/v3/server"
+	"go.unistack.org/micro/v4/client"
+	"go.unistack.org/micro/v4/metadata"
+	"go.unistack.org/micro/v4/server"
 )
 
-var DefaultMetadataKeys = []string{"x-request-id"}
-
-type hook struct {
+type wrapper struct {
 	keys []string
+
+	client.Client
 }
 
-func NewHook(keys ...string) *hook {
-	return &hook{keys: keys}
+func NewClientWrapper(keys ...string) client.Wrapper {
+	return func(c client.Client) client.Client {
+		handler := &wrapper{
+			Client: c,
+			keys:   keys,
+		}
+		return handler
+	}
 }
 
-func metadataCopy(ctx context.Context, keys []string) context.Context {
-	if keys == nil {
-		return ctx
+func NewClientCallWrapper(keys ...string) client.CallWrapper {
+	return func(fn client.CallFunc) client.CallFunc {
+		return func(ctx context.Context, addr string, req client.Request, rsp interface{}, opts client.CallOptions) error {
+			if keys == nil {
+				return fn(ctx, addr, req, rsp, opts)
+			}
+			if imd, iok := metadata.FromIncomingContext(ctx); iok && imd != nil {
+				omd, ook := metadata.FromOutgoingContext(ctx)
+				if !ook || omd == nil {
+					omd = metadata.New(len(imd))
+				}
+				for _, k := range keys {
+					if v := imd.Get(k); v != nil {
+						omd.Set(k, v...)
+					}
+				}
+				if !ook {
+					ctx = metadata.NewOutgoingContext(ctx, omd)
+				}
+			}
+			return fn(ctx, addr, req, rsp, opts)
+		}
+	}
+}
+
+func (w *wrapper) Call(ctx context.Context, req client.Request, rsp interface{}, opts ...client.CallOption) error {
+	if w.keys == nil {
+		return w.Client.Call(ctx, req, rsp, opts...)
 	}
 	if imd, iok := metadata.FromIncomingContext(ctx); iok && imd != nil {
 		omd, ook := metadata.FromOutgoingContext(ctx)
 		if !ook || omd == nil {
-			omd = metadata.New(len(keys))
+			omd = metadata.New(len(imd))
 		}
-		for _, k := range keys {
-			if v, ok := imd.Get(k); ok && v != "" {
-				omd.Set(k, v)
+		for _, k := range w.keys {
+			if v := imd.Get(k); v != nil {
+				omd.Set(k, v...)
 			}
 		}
 		if !ook {
 			ctx = metadata.NewOutgoingContext(ctx, omd)
 		}
 	}
-	return ctx
+	return w.Client.Call(ctx, req, rsp, opts...)
 }
 
-func (w *hook) ClientCall(next client.FuncCall) client.FuncCall {
-	return func(ctx context.Context, req client.Request, rsp interface{}, opts ...client.CallOption) error {
-		return next(metadataCopy(ctx, w.keys), req, rsp, opts...)
+func (w *wrapper) Stream(ctx context.Context, req client.Request, opts ...client.CallOption) (client.Stream, error) {
+	if w.keys == nil {
+		return w.Client.Stream(ctx, req, opts...)
 	}
+	if imd, iok := metadata.FromIncomingContext(ctx); iok && imd != nil {
+		omd, ook := metadata.FromOutgoingContext(ctx)
+		if !ook || omd == nil {
+			omd = metadata.New(len(imd))
+		}
+		for _, k := range w.keys {
+			if v := imd.Get(k); v != nil {
+				omd.Set(k, v...)
+			}
+		}
+		if !ook {
+			ctx = metadata.NewOutgoingContext(ctx, omd)
+		}
+	}
+	return w.Client.Stream(ctx, req, opts...)
 }
 
-func (w *hook) ClientStream(next client.FuncStream) client.FuncStream {
-	return func(ctx context.Context, req client.Request, opts ...client.CallOption) (client.Stream, error) {
-		return next(metadataCopy(ctx, w.keys), req, opts...)
-	}
-}
-
-func (w *hook) ClientPublish(next client.FuncPublish) client.FuncPublish {
-	return func(ctx context.Context, msg client.Message, opts ...client.PublishOption) error {
-		return next(metadataCopy(ctx, w.keys), msg, opts...)
-	}
-}
-
-func (w *hook) ClientBatchPublish(next client.FuncBatchPublish) client.FuncBatchPublish {
-	return func(ctx context.Context, msgs []client.Message, opts ...client.PublishOption) error {
-		return next(metadataCopy(ctx, w.keys), msgs, opts...)
-	}
-}
-
-func (w *hook) ServerHandler(next server.FuncHandler) server.FuncHandler {
-	return func(ctx context.Context, req server.Request, rsp interface{}) error {
-		return next(metadataCopy(ctx, w.keys), req, rsp)
-	}
-}
-
-func (w *hook) ServerSubscriber(next server.FuncSubHandler) server.FuncSubHandler {
-	return func(ctx context.Context, msg server.Message) error {
-		return next(metadataCopy(ctx, w.keys), msg)
+func NewServerHandlerWrapper(keys ...string) server.HandlerWrapper {
+	return func(fn server.HandlerFunc) server.HandlerFunc {
+		return func(ctx context.Context, req server.Request, rsp interface{}) error {
+			if keys == nil {
+				return fn(ctx, req, rsp)
+			}
+			if imd, iok := metadata.FromIncomingContext(ctx); iok && imd != nil {
+				omd, ook := metadata.FromOutgoingContext(ctx)
+				if !ook || omd == nil {
+					omd = metadata.New(len(imd))
+				}
+				for _, k := range keys {
+					if v := imd.Get(k); v != nil {
+						omd.Set(k, v...)
+					}
+				}
+				if !ook {
+					ctx = metadata.NewOutgoingContext(ctx, omd)
+				}
+			}
+			return fn(ctx, req, rsp)
+		}
 	}
 }

hooks/recovery/recovery.go

@@ -4,14 +4,13 @@ import (
 	"context"
 	"fmt"
 
-	"go.unistack.org/micro/v3/errors"
-	"go.unistack.org/micro/v3/server"
+	"go.unistack.org/micro/v4/errors"
+	"go.unistack.org/micro/v4/server"
 )
 
 func NewOptions(opts ...Option) Options {
 	options := Options{
-		ServerHandlerFn:    DefaultServerHandlerFn,
-		ServerSubscriberFn: DefaultServerSubscriberFn,
+		ServerHandlerFn: DefaultServerHandlerFn,
 	}
 	for _, o := range opts {
 		o(&options)
@@ -20,8 +19,7 @@ func NewOptions(opts ...Option) Options {
 }
 
 type Options struct {
-	ServerHandlerFn    func(context.Context, server.Request, interface{}, error) error
-	ServerSubscriberFn func(context.Context, server.Message, error) error
+	ServerHandlerFn func(context.Context, server.Request, interface{}, error) error
 }
 
 type Option func(*Options)
@@ -32,21 +30,10 @@ func ServerHandlerFunc(fn func(context.Context, server.Request, interface{}, err
 	}
 }
 
-func ServerSubscriberFunc(fn func(context.Context, server.Message, error) error) Option {
-	return func(o *Options) {
-		o.ServerSubscriberFn = fn
-	}
+var DefaultServerHandlerFn = func(ctx context.Context, req server.Request, rsp interface{}, err error) error {
+	return errors.BadRequest("", "%v", err)
 }
 
-var (
-	DefaultServerHandlerFn = func(ctx context.Context, req server.Request, rsp interface{}, err error) error {
-		return errors.BadRequest("", "%v", err)
-	}
-	DefaultServerSubscriberFn = func(ctx context.Context, req server.Message, err error) error {
-		return errors.BadRequest("", "%v", err)
-	}
-)
-
 var Hook = NewHook()
 
 type hook struct {
@@ -74,21 +61,3 @@ func (w *hook) ServerHandler(next server.FuncHandler) server.FuncHandler {
 		return err
 	}
 }
-
-func (w *hook) ServerSubscriber(next server.FuncSubHandler) server.FuncSubHandler {
-	return func(ctx context.Context, msg server.Message) (err error) {
-		defer func() {
-			r := recover()
-			switch verr := r.(type) {
-			case nil:
-				return
-			case error:
-				err = w.opts.ServerSubscriberFn(ctx, msg, verr)
-			default:
-				err = w.opts.ServerSubscriberFn(ctx, msg, fmt.Errorf("%v", r))
-			}
-		}()
-		err = next(ctx, msg)
-		return err
-	}
-}

hooks/requestid/requestid.go

@@ -3,11 +3,11 @@ package requestid
 import (
 	"context"
 	"net/textproto"
-	
-	"go.unistack.org/micro/v3/client"
-	"go.unistack.org/micro/v3/metadata"
-	"go.unistack.org/micro/v3/server"
-	"go.unistack.org/micro/v3/util/id"
+
+	"go.unistack.org/micro/v4/client"
+	"go.unistack.org/micro/v4/metadata"
+	"go.unistack.org/micro/v4/server"
+	"go.unistack.org/micro/v4/util/id"
 )
 
 type XRequestIDKey struct{}
@@ -37,12 +37,9 @@ var DefaultMetadataFunc = func(ctx context.Context) (context.Context, error) {
 	}
 
 	if xid == "" {
-		var id string
-		if id, iok = imd.Get(DefaultMetadataKey); iok && id != "" {
-			xid = id
-		}
-		if id, ook = omd.Get(DefaultMetadataKey); ook && id != "" {
-			xid = id
+		xid = imd.GetJoined(DefaultMetadataKey)
+		if xid == "" {
+			xid = omd.GetJoined(DefaultMetadataKey)
 		}
 	}
 
@@ -75,19 +72,6 @@ func NewHook() *hook {
 	return &hook{}
 }
 
-func (w *hook) ServerSubscriber(next server.FuncSubHandler) server.FuncSubHandler {
-	return func(ctx context.Context, msg server.Message) error {
-		var err error
-		if xid, ok := msg.Header()[DefaultMetadataKey]; ok {
-			ctx = context.WithValue(ctx, XRequestIDKey{}, xid)
-		}
-		if ctx, err = DefaultMetadataFunc(ctx); err != nil {
-			return err
-		}
-		return next(ctx, msg)
-	}
-}
-
 func (w *hook) ServerHandler(next server.FuncHandler) server.FuncHandler {
 	return func(ctx context.Context, req server.Request, rsp interface{}) error {
 		var err error
@@ -98,26 +82,6 @@ func (w *hook) ServerHandler(next server.FuncHandler) server.FuncHandler {
 	}
 }
 
-func (w *hook) ClientBatchPublish(next client.FuncBatchPublish) client.FuncBatchPublish {
-	return func(ctx context.Context, msgs []client.Message, opts ...client.PublishOption) error {
-		var err error
-		if ctx, err = DefaultMetadataFunc(ctx); err != nil {
-			return err
-		}
-		return next(ctx, msgs, opts...)
-	}
-}
-
-func (w *hook) ClientPublish(next client.FuncPublish) client.FuncPublish {
-	return func(ctx context.Context, msg client.Message, opts ...client.PublishOption) error {
-		var err error
-		if ctx, err = DefaultMetadataFunc(ctx); err != nil {
-			return err
-		}
-		return next(ctx, msg, opts...)
-	}
-}
-
 func (w *hook) ClientCall(next client.FuncCall) client.FuncCall {
 	return func(ctx context.Context, req client.Request, rsp interface{}, opts ...client.CallOption) error {
 		var err error

hooks/requestid/requestid_test.go

@@ -2,9 +2,10 @@ package requestid
 
 import (
 	"context"
+	"slices"
 	"testing"
 
-	"go.unistack.org/micro/v3/metadata"
+	"go.unistack.org/micro/v4/metadata"
 )
 
 func TestDefaultMetadataFunc(t *testing.T) {
@@ -24,10 +25,10 @@ func TestDefaultMetadataFunc(t *testing.T) {
 		t.Fatalf("md missing in outgoing context")
 	}
 
-	_, iok := imd.Get(DefaultMetadataKey)
-	_, ook := omd.Get(DefaultMetadataKey)
+	iv := imd.Get(DefaultMetadataKey)
+	ov := omd.Get(DefaultMetadataKey)
 
-	if !iok || !ook {
-		t.Fatalf("missing metadata key value")
+	if !slices.Equal(iv, ov) {
+		t.Fatalf("missing metadata key value %v != %v", iv, ov)
 	}
 }

hooks/sql/conn.go

@@ -6,8 +6,8 @@ import (
 	"fmt"
 	"time"
 
-	"go.unistack.org/micro/v3/hooks/requestid"
-	"go.unistack.org/micro/v3/tracer"
+	"go.unistack.org/micro/v4/hooks/requestid"
+	"go.unistack.org/micro/v4/tracer"
 )
 
 var (
@@ -324,7 +324,7 @@ func (w *wrapperConn) Ping(ctx context.Context) error {
 		return pc.Close()
 	}
 
-	var nctx context.Context //nolint: gosimple
+	var nctx context.Context //nolint:gosimple
 	nctx = ctx
 	/*
 		var span tracer.Span

hooks/sql/gen.go

@@ -67,9 +67,10 @@ func main() {
 		}
 		h := getHash(ifaces)
 		b.WriteString(fmt.Sprintf("\tif _, ok := dc.(wrapConn%04d_%s); ok {\n", n, h))
-		b.WriteString("\t\treturn struct {\n")
-		b.WriteString(strings.Join(append([]string{"\t\t\tdriver.Conn"}, ifaces...), "\n\t\t\t"))
-		b.WriteString("\n\t\t}{")
+		b.WriteString("\treturn struct {\n")
+		b.WriteString("\t\tdriver.Conn\n")
+		b.WriteString(fmt.Sprintf("\t\t\t%s", strings.Join(ifaces, "\n\t\t\t")))
+		b.WriteString("\t\t\n}{")
 		for idx := range ifaces {
 			if idx > 0 {
 				b.WriteString(", ")
@@ -81,10 +82,10 @@ func main() {
 			}
 		}
 		b.WriteString(", c}\n")
-		b.WriteString("\t}\n\n")
+		b.WriteString("}\n\n")
 	}
-	b.WriteString("\treturn c\n")
-	b.WriteString("}\n\n")
+	b.WriteString("return c\n")
+	b.WriteString("}\n")
 
 	for idx := len(comboConn) - 1; idx >= 0; idx-- {
 		ifaces := comboConn[idx]
@@ -112,9 +113,10 @@ func main() {
 		}
 		h := getHash(ifaces)
 		b.WriteString(fmt.Sprintf("\tif _, ok := stmt.(wrapStmt%04d_%s); ok {\n", n, h))
-		b.WriteString("\t\treturn struct {\n")
-		b.WriteString(strings.Join(append([]string{"\t\t\tdriver.Stmt"}, ifaces...), "\n\t\t\t"))
-		b.WriteString("\n\t\t}{")
+		b.WriteString("\treturn struct {\n")
+		b.WriteString("\t\tdriver.Stmt\n")
+		b.WriteString(fmt.Sprintf("\t\t\t%s", strings.Join(ifaces, "\n\t\t\t")))
+		b.WriteString("\t\t\n}{")
 		for idx := range ifaces {
 			if idx > 0 {
 				b.WriteString(", ")
@@ -126,9 +128,9 @@ func main() {
 			}
 		}
 		b.WriteString(", c}\n")
-		b.WriteString("\t}\n\n")
+		b.WriteString("}\n\n")
 	}
-	b.WriteString("\treturn c\n")
+	b.WriteString("return c\n")
 	b.WriteString("}\n")
 
 	for idx := len(comboStmt) - 1; idx >= 0; idx-- {
@@ -138,15 +140,15 @@ func main() {
 			continue
 		}
 		h := getHash(ifaces)
-		b.WriteString(fmt.Sprintf("\n// %s\n", strings.Join(ifaces, "|")))
+		b.WriteString(fmt.Sprintf("// %s\n", strings.Join(ifaces, "|")))
 		b.WriteString(fmt.Sprintf("type wrapStmt%04d_%s interface {\n", n, h))
 		for _, iface := range ifaces {
 			b.WriteString(fmt.Sprintf("\t%s\n", iface))
 		}
-		b.WriteString("}\n")
+		b.WriteString("}\n\n")
 	}
 
-	fmt.Printf("%s", b.String())
+	fmt.Printf("%s\n", b.String())
 }
 
 // all returns all combinations for a given string array.

hooks/sql/options.go

@@ -5,9 +5,9 @@ import (
 	"fmt"
 	"time"
 
-	"go.unistack.org/micro/v3/logger"
-	"go.unistack.org/micro/v3/meter"
-	"go.unistack.org/micro/v3/tracer"
+	"go.unistack.org/micro/v4/logger"
+	"go.unistack.org/micro/v4/meter"
+	"go.unistack.org/micro/v4/tracer"
 )
 
 var (

hooks/sql/stats.go

@@ -3,6 +3,7 @@ package sql
 import (
 	"context"
 	"database/sql"
+	"sync"
 	"time"
 )
 
@@ -11,31 +12,84 @@ type Statser interface {
 }
 
 func NewStatsMeter(ctx context.Context, db Statser, opts ...Option) {
+	if db == nil {
+		return
+	}
+
 	options := NewOptions(opts...)
 
-	go func() {
-		ticker := time.NewTicker(options.MeterStatsInterval)
-		defer ticker.Stop()
+	var (
+		statsMu                                                     sync.Mutex
+		lastUpdated                                                 time.Time
+		maxOpenConnections, openConnections, inUse, idle, waitCount float64
+		maxIdleClosed, maxIdleTimeClosed, maxLifetimeClosed         float64
+		waitDuration                                                float64
+	)
 
-		for {
-			select {
-			case <-ctx.Done():
-				return
-			case <-ticker.C:
-				if db == nil {
-					return
-				}
-				stats := db.Stats()
-				options.Meter.Counter(MaxOpenConnections).Set(uint64(stats.MaxOpenConnections))
-				options.Meter.Counter(OpenConnections).Set(uint64(stats.OpenConnections))
-				options.Meter.Counter(InuseConnections).Set(uint64(stats.InUse))
-				options.Meter.Counter(IdleConnections).Set(uint64(stats.Idle))
-				options.Meter.Counter(WaitConnections).Set(uint64(stats.WaitCount))
-				options.Meter.FloatCounter(BlockedSeconds).Set(stats.WaitDuration.Seconds())
-				options.Meter.Counter(MaxIdleClosed).Set(uint64(stats.MaxIdleClosed))
-				options.Meter.Counter(MaxIdletimeClosed).Set(uint64(stats.MaxIdleTimeClosed))
-				options.Meter.Counter(MaxLifetimeClosed).Set(uint64(stats.MaxLifetimeClosed))
-			}
+	updateFn := func() {
+		statsMu.Lock()
+		defer statsMu.Unlock()
+
+		if time.Since(lastUpdated) < options.MeterStatsInterval {
+			return
 		}
-	}()
+
+		stats := db.Stats()
+		maxOpenConnections = float64(stats.MaxOpenConnections)
+		openConnections = float64(stats.OpenConnections)
+		inUse = float64(stats.InUse)
+		idle = float64(stats.Idle)
+		waitCount = float64(stats.WaitCount)
+		maxIdleClosed = float64(stats.MaxIdleClosed)
+		maxIdleTimeClosed = float64(stats.MaxIdleTimeClosed)
+		maxLifetimeClosed = float64(stats.MaxLifetimeClosed)
+		waitDuration = float64(stats.WaitDuration.Seconds())
+
+		lastUpdated = time.Now()
+	}
+
+	options.Meter.Gauge(MaxOpenConnections, func() float64 {
+		updateFn()
+		return maxOpenConnections
+	})
+
+	options.Meter.Gauge(OpenConnections, func() float64 {
+		updateFn()
+		return openConnections
+	})
+
+	options.Meter.Gauge(InuseConnections, func() float64 {
+		updateFn()
+		return inUse
+	})
+
+	options.Meter.Gauge(IdleConnections, func() float64 {
+		updateFn()
+		return idle
+	})
+
+	options.Meter.Gauge(WaitConnections, func() float64 {
+		updateFn()
+		return waitCount
+	})
+
+	options.Meter.Gauge(BlockedSeconds, func() float64 {
+		updateFn()
+		return waitDuration
+	})
+
+	options.Meter.Gauge(MaxIdleClosed, func() float64 {
+		updateFn()
+		return maxIdleClosed
+	})
+
+	options.Meter.Gauge(MaxIdletimeClosed, func() float64 {
+		updateFn()
+		return maxIdleTimeClosed
+	})
+
+	options.Meter.Gauge(MaxLifetimeClosed, func() float64 {
+		updateFn()
+		return maxLifetimeClosed
+	})
 }

hooks/sql/stmt.go

@@ -6,8 +6,8 @@ import (
 	"fmt"
 	"time"
 
-	"go.unistack.org/micro/v3/hooks/requestid"
-	"go.unistack.org/micro/v3/tracer"
+	requestid "go.unistack.org/micro/v4/hooks/requestid"
+	"go.unistack.org/micro/v4/tracer"
 )
 
 var (

hooks/sql/tx.go

@@ -5,7 +5,7 @@ import (
 	"database/sql/driver"
 	"time"
 
-	"go.unistack.org/micro/v3/tracer"
+	"go.unistack.org/micro/v4/tracer"
 )
 
 var _ driver.Tx = (*wrapperTx)(nil)

hooks/validator/validator.go

@@ -3,9 +3,9 @@ package validator
 import (
 	"context"
 
-	"go.unistack.org/micro/v3/client"
-	"go.unistack.org/micro/v3/errors"
-	"go.unistack.org/micro/v3/server"
+	"go.unistack.org/micro/v4/client"
+	"go.unistack.org/micro/v4/errors"
+	"go.unistack.org/micro/v4/server"
 )
 
 var (
@@ -22,29 +22,17 @@ var (
 		}
 		return errors.BadRequest(req.Service(), "%v", err)
 	}
-
-	DefaultPublishErrorFunc = func(msg client.Message, err error) error {
-		return errors.BadRequest(msg.Topic(), "%v", err)
-	}
-
-	DefaultSubscribeErrorFunc = func(msg server.Message, err error) error {
-		return errors.BadRequest(msg.Topic(), "%v", err)
-	}
 )
 
 type (
-	ClientErrorFunc    func(client.Request, interface{}, error) error
-	ServerErrorFunc    func(server.Request, interface{}, error) error
-	PublishErrorFunc   func(client.Message, error) error
-	SubscribeErrorFunc func(server.Message, error) error
+	ClientErrorFunc func(client.Request, interface{}, error) error
+	ServerErrorFunc func(server.Request, interface{}, error) error
 )
 
 // Options struct holds wrapper options
 type Options struct {
 	ClientErrorFn          ClientErrorFunc
 	ServerErrorFn          ServerErrorFunc
-	PublishErrorFn         PublishErrorFunc
-	SubscribeErrorFn       SubscribeErrorFunc
 	ClientValidateResponse bool
 	ServerValidateResponse bool
 }
@@ -76,24 +64,10 @@ func ServerErrorFn(fn ServerErrorFunc) Option {
 	}
 }
 
-func PublishErrorFn(fn PublishErrorFunc) Option {
-	return func(o *Options) {
-		o.PublishErrorFn = fn
-	}
-}
-
-func SubscribeErrorFn(fn SubscribeErrorFunc) Option {
-	return func(o *Options) {
-		o.SubscribeErrorFn = fn
-	}
-}
-
 func NewOptions(opts ...Option) Options {
 	options := Options{
-		ClientErrorFn:    DefaultClientErrorFunc,
-		ServerErrorFn:    DefaultServerErrorFunc,
-		PublishErrorFn:   DefaultPublishErrorFunc,
-		SubscribeErrorFn: DefaultSubscribeErrorFunc,
+		ClientErrorFn: DefaultClientErrorFunc,
+		ServerErrorFn: DefaultServerErrorFunc,
 	}
 	for _, o := range opts {
 		o(&options)
@@ -141,30 +115,6 @@ func (w *hook) ClientStream(next client.FuncStream) client.FuncStream {
 	}
 }
 
-func (w *hook) ClientPublish(next client.FuncPublish) client.FuncPublish {
-	return func(ctx context.Context, msg client.Message, opts ...client.PublishOption) error {
-		if v, ok := msg.Payload().(validator); ok {
-			if err := v.Validate(); err != nil {
-				return w.opts.PublishErrorFn(msg, err)
-			}
-		}
-		return next(ctx, msg, opts...)
-	}
-}
-
-func (w *hook) ClientBatchPublish(next client.FuncBatchPublish) client.FuncBatchPublish {
-	return func(ctx context.Context, msgs []client.Message, opts ...client.PublishOption) error {
-		for _, msg := range msgs {
-			if v, ok := msg.Payload().(validator); ok {
-				if err := v.Validate(); err != nil {
-					return w.opts.PublishErrorFn(msg, err)
-				}
-			}
-		}
-		return next(ctx, msgs, opts...)
-	}
-}
-
 func (w *hook) ServerHandler(next server.FuncHandler) server.FuncHandler {
 	return func(ctx context.Context, req server.Request, rsp interface{}) error {
 		if v, ok := req.Body().(validator); ok {
@@ -181,14 +131,3 @@ func (w *hook) ServerHandler(next server.FuncHandler) server.FuncHandler {
 		return err
 	}
 }
-
-func (w *hook) ServerSubscriber(next server.FuncSubHandler) server.FuncSubHandler {
-	return func(ctx context.Context, msg server.Message) error {
-		if v, ok := msg.Body().(validator); ok {
-			if err := v.Validate(); err != nil {
-				return w.opts.SubscribeErrorFn(msg, err)
-			}
-		}
-		return next(ctx, msg)
-	}
-}

logger/level.go

@@ -4,18 +4,20 @@ package logger
 type Level int8
 
 const (
-	// TraceLevel level usually used to find bugs, very verbose
+	// TraceLevel usually used to find bugs, very verbose
 	TraceLevel Level = iota - 2
-	// DebugLevel level used only when enabled debugging
+	// DebugLevel used only when enabled debugging
 	DebugLevel
-	// InfoLevel level used for general info about what's going on inside the application
+	// InfoLevel used for general info about what's going on inside the application
 	InfoLevel
-	// WarnLevel level used for non-critical entries
+	// WarnLevel used for non-critical entries
 	WarnLevel
-	// ErrorLevel level used for errors that should definitely be noted
+	// ErrorLevel used for errors that should definitely be noted
 	ErrorLevel
-	// FatalLevel level used for critical errors and then calls `os.Exit(1)`
+	// FatalLevel used for critical errors and then calls `os.Exit(1)`
 	FatalLevel
+	// NoneLevel used to disable logging
+	NoneLevel
 )
 
 // String returns logger level string representation
@@ -33,6 +35,8 @@ func (l Level) String() string {
 		return "error"
 	case FatalLevel:
 		return "fatal"
+	case NoneLevel:
+		return "none"
 	}
 	return "info"
 }
@@ -58,6 +62,8 @@ func ParseLevel(lvl string) Level {
 		return ErrorLevel
 	case FatalLevel.String():
 		return FatalLevel
+	case NoneLevel.String():
+		return NoneLevel
 	}
 	return InfoLevel
 }

logger/options.go

@@ -8,7 +8,7 @@ import (
 	"slices"
 	"time"
 
-	"go.unistack.org/micro/v3/meter"
+	"go.unistack.org/micro/v4/meter"
 )
 
 // Option func signature

logger/slog/slog.go

@@ -13,9 +13,9 @@ import (
 	"sync/atomic"
 	"time"
 
-	"go.unistack.org/micro/v3/logger"
-	"go.unistack.org/micro/v3/semconv"
-	"go.unistack.org/micro/v3/tracer"
+	"go.unistack.org/micro/v4/logger"
+	"go.unistack.org/micro/v4/semconv"
+	"go.unistack.org/micro/v4/tracer"
 )
 
 const (
@@ -34,6 +34,7 @@ var (
 	warnValue  = slog.StringValue("warn")
 	errorValue = slog.StringValue("error")
 	fatalValue = slog.StringValue("fatal")
+	noneValue  = slog.StringValue("none")
 )
 
 type wrapper struct {
@@ -85,6 +86,8 @@ func (s *slogLogger) renameAttr(_ []string, a slog.Attr) slog.Attr {
 			a.Value = errorValue
 		case lvl >= logger.FatalLevel:
 			a.Value = fatalValue
+		case lvl >= logger.NoneLevel:
+			a.Value = noneValue
 		default:
 			a.Value = infoValue
 		}
@@ -316,6 +319,8 @@ func loggerToSlogLevel(level logger.Level) slog.Level {
 		return slog.LevelDebug - 1
 	case logger.FatalLevel:
 		return slog.LevelError + 1
+	case logger.NoneLevel:
+		return slog.LevelError + 2
 	default:
 		return slog.LevelInfo
 	}
@@ -333,6 +338,8 @@ func slogToLoggerLevel(level slog.Level) logger.Level {
 		return logger.TraceLevel
 	case slog.LevelError + 1:
 		return logger.FatalLevel
+	case slog.LevelError + 2:
+		return logger.NoneLevel
 	default:
 		return logger.InfoLevel
 	}

logger/slog/slog_test.go

@@ -12,9 +12,9 @@ import (
 	"time"
 
 	"github.com/google/uuid"
-	"go.unistack.org/micro/v3/logger"
-	"go.unistack.org/micro/v3/metadata"
-	"go.unistack.org/micro/v3/util/buffer"
+	"go.unistack.org/micro/v4/logger"
+	"go.unistack.org/micro/v4/metadata"
+	"go.unistack.org/micro/v4/util/buffer"
 )
 
 // always first to have proper check
@@ -36,6 +36,24 @@ func TestStacktrace(t *testing.T) {
 	}
 }
 
+func TestNoneLevel(t *testing.T) {
+	ctx := context.TODO()
+	buf := bytes.NewBuffer(nil)
+	l := NewLogger(logger.WithLevel(logger.NoneLevel), logger.WithOutput(buf),
+		WithHandlerFunc(slog.NewTextHandler),
+		logger.WithAddStacktrace(true),
+	)
+	if err := l.Init(logger.WithFields("key1", "val1")); err != nil {
+		t.Fatal(err)
+	}
+
+	l.Error(ctx, "msg1", errors.New("err"))
+
+	if buf.Len() != 0 {
+		t.Fatalf("logger none level not works, buf contains: %s", buf.Bytes())
+	}
+}
+
 func TestDelayedBuffer(t *testing.T) {
 	ctx := context.TODO()
 	buf := bytes.NewBuffer(nil)
@@ -405,15 +423,16 @@ func TestLogger(t *testing.T) {
 func Test_WithContextAttrFunc(t *testing.T) {
 	loggerContextAttrFuncs := []logger.ContextAttrFunc{
 		func(ctx context.Context) []interface{} {
-			md, ok := metadata.FromIncomingContext(ctx)
+			md, ok := metadata.FromOutgoingContext(ctx)
 			if !ok {
 				return nil
 			}
 			attrs := make([]interface{}, 0, 10)
 			for k, v := range md {
-				switch k {
-				case "X-Request-Id", "Phone", "External-Id", "Source-Service", "X-App-Install-Id", "Client-Id", "Client-Ip":
-					attrs = append(attrs, strings.ToLower(k), v)
+				key := strings.ToLower(k)
+				switch key {
+				case "x-request-id", "phone", "external-Id", "source-service", "x-app-install-id", "client-id", "client-ip":
+					attrs = append(attrs, key, v[0])
 				}
 			}
 			return attrs
@@ -423,7 +442,7 @@ func Test_WithContextAttrFunc(t *testing.T) {
 	logger.DefaultContextAttrFuncs = append(logger.DefaultContextAttrFuncs, loggerContextAttrFuncs...)
 
 	ctx := context.TODO()
-	ctx = metadata.AppendIncomingContext(ctx, "X-Request-Id", uuid.New().String(),
+	ctx = metadata.AppendOutgoingContext(ctx, "X-Request-Id", uuid.New().String(),
 		"Source-Service", "Test-System")
 
 	buf := bytes.NewBuffer(nil)
@@ -443,9 +462,9 @@ func Test_WithContextAttrFunc(t *testing.T) {
 		t.Fatalf("logger info, buf %s", buf.Bytes())
 	}
 	buf.Reset()
-	imd, _ := metadata.FromIncomingContext(ctx)
+	omd, _ := metadata.FromOutgoingContext(ctx)
 	l.Info(ctx, "test message1")
-	imd.Set("Source-Service", "Test-System2")
+	omd.Set("Source-Service", "Test-System2")
 	l.Info(ctx, "test message2")
 
 	// t.Logf("xxx %s", buf.Bytes())

logger/unwrap/unwrap.go

@@ -8,7 +8,7 @@ import (
 	"strconv"
 	"strings"
 
-	"go.unistack.org/micro/v3/codec"
+	"go.unistack.org/micro/v4/codec"
 )
 
 const sf = "0-+# "

logger/unwrap/unwrap_test.go

@@ -5,7 +5,7 @@ import (
 	"strings"
 	"testing"
 
-	"go.unistack.org/micro/v3/codec"
+	"go.unistack.org/micro/v4/codec"
 )
 
 func TestUnwrap(t *testing.T) {

metadata/context.go

@@ -1,79 +1,147 @@
-// Package metadata is a way of defining message headers
 package metadata
 
 import (
 	"context"
+	"fmt"
+	"strings"
 )
 
+// In the metadata package, context and metadata are treated as immutable.
+// Deep copies of metadata are made to keep things safe and correct.
+// If a user takes a map and changes it across threads, it's their responsibility.
+//
+// 1. Incoming Context
+//
+// This context is provided by an external system and populated by the server or broker of the micro framework.
+// It should not be modified. The idea is to extract all necessary data from it,
+// validate the data, and transfer it into the current context.
+// After that, only the current context should be used throughout the code.
+//
+// 2. Current Context
+//
+// This is the context used during the execution flow.
+// You can add any needed metadata to it and pass it through your code.
+//
+// 3. Outgoing Context
+//
+// This context is for sending data to external systems.
+// You can add what you need before sending it out.
+// But it’s usually better to build and prepare this context right before making the external call,
+// instead of changing it in many places.
+//
+// Execution Flow:
+//
+// [External System]
+//       ↓
+// [Incoming Context]
+//       ↓
+// [Extract & Validate Metadata from Incoming Context]
+//       ↓
+// [Prepare Current Context]
+//       ↓
+// [Enrich Current Context]
+//       ↓
+// [Business Logic]
+//       ↓
+// [Prepare Outgoing Context]
+//       ↓
+// [External System Call]
+
 type (
-	mdIncomingKey struct{}
-	mdOutgoingKey struct{}
-	mdKey         struct{}
+	metadataCurrentKey  struct{}
+	metadataIncomingKey struct{}
+	metadataOutgoingKey struct{}
+
+	rawMetadata struct {
+		md    Metadata
+		added [][]string
+	}
 )
 
-// FromIncomingContext returns metadata from incoming ctx
-// returned metadata shoud not be modified or race condition happens
-func FromIncomingContext(ctx context.Context) (Metadata, bool) {
-	if ctx == nil {
-		return nil, false
-	}
-	md, ok := ctx.Value(mdIncomingKey{}).(*rawMetadata)
-	if !ok || md.md == nil {
-		return nil, false
-	}
-	return md.md, ok
+// NewContext creates a new context with the provided Metadata attached.
+// The Metadata must not be modified after calling this function.
+func NewContext(ctx context.Context, md Metadata) context.Context {
+	return context.WithValue(ctx, metadataCurrentKey{}, rawMetadata{md: md})
 }
 
-// MustIncomingContext returns metadata from incoming ctx
-// returned metadata shoud not be modified or race condition happens.
-// If metadata not exists panics.
-func MustIncomingContext(ctx context.Context) Metadata {
-	md, ok := FromIncomingContext(ctx)
-	if !ok {
-		panic("missing metadata")
-	}
-	return md
+// NewIncomingContext creates a new context with the provided incoming Metadata attached.
+// The Metadata must not be modified after calling this function.
+func NewIncomingContext(ctx context.Context, md Metadata) context.Context {
+	return context.WithValue(ctx, metadataIncomingKey{}, rawMetadata{md: md})
 }
 
-// FromOutgoingContext returns metadata from outgoing ctx
-// returned metadata shoud not be modified or race condition happens
-func FromOutgoingContext(ctx context.Context) (Metadata, bool) {
-	if ctx == nil {
-		return nil, false
-	}
-	md, ok := ctx.Value(mdOutgoingKey{}).(*rawMetadata)
-	if !ok || md.md == nil {
-		return nil, false
-	}
-	return md.md, ok
+// NewOutgoingContext creates a new context with the provided outgoing Metadata attached.
+// The Metadata must not be modified after calling this function.
+func NewOutgoingContext(ctx context.Context, md Metadata) context.Context {
+	return context.WithValue(ctx, metadataOutgoingKey{}, rawMetadata{md: md})
 }
 
-// MustOutgoingContext returns metadata from outgoing ctx
-// returned metadata shoud not be modified or race condition happens.
-// If metadata not exists panics.
-func MustOutgoingContext(ctx context.Context) Metadata {
-	md, ok := FromOutgoingContext(ctx)
-	if !ok {
-		panic("missing metadata")
+// AppendContext returns a new context with the provided key-value pairs (kv)
+// merged with any existing metadata in the context. For a description of kv,
+// please refer to the Pairs documentation.
+func AppendContext(ctx context.Context, kv ...string) context.Context {
+	if len(kv)%2 == 1 {
+		panic(fmt.Sprintf("metadata: AppendContext got an odd number of input pairs for metadata: %d", len(kv)))
 	}
-	return md
+	md, _ := ctx.Value(metadataCurrentKey{}).(rawMetadata)
+	added := make([][]string, len(md.added)+1)
+	copy(added, md.added)
+	kvCopy := make([]string, 0, len(kv))
+	for i := 0; i < len(kv); i += 2 {
+		kvCopy = append(kvCopy, strings.ToLower(kv[i]), kv[i+1])
+	}
+	added[len(added)-1] = kvCopy
+	return context.WithValue(ctx, metadataCurrentKey{}, rawMetadata{md: md.md, added: added})
 }
 
-// FromContext returns metadata from the given context
-// returned metadata shoud not be modified or race condition happens
+// AppendOutgoingContext returns a new context with the provided key-value pairs (kv)
+// merged with any existing metadata in the context. For a description of kv,
+// please refer to the Pairs documentation.
+func AppendOutgoingContext(ctx context.Context, kv ...string) context.Context {
+	if len(kv)%2 == 1 {
+		panic(fmt.Sprintf("metadata: AppendOutgoingContext got an odd number of input pairs for metadata: %d", len(kv)))
+	}
+	md, _ := ctx.Value(metadataOutgoingKey{}).(rawMetadata)
+	added := make([][]string, len(md.added)+1)
+	copy(added, md.added)
+	kvCopy := make([]string, 0, len(kv))
+	for i := 0; i < len(kv); i += 2 {
+		kvCopy = append(kvCopy, strings.ToLower(kv[i]), kv[i+1])
+	}
+	added[len(added)-1] = kvCopy
+	return context.WithValue(ctx, metadataOutgoingKey{}, rawMetadata{md: md.md, added: added})
+}
+
+// FromContext retrieves a deep copy of the metadata from the context and returns it
+// with a boolean indicating if it was found.
 func FromContext(ctx context.Context) (Metadata, bool) {
-	if ctx == nil {
+	raw, ok := ctx.Value(metadataCurrentKey{}).(rawMetadata)
+	if !ok {
 		return nil, false
 	}
-	md, ok := ctx.Value(mdKey{}).(*rawMetadata)
-	if !ok || md.md == nil {
-		return nil, false
+	metadataSize := len(raw.md)
+	for i := range raw.added {
+		metadataSize += len(raw.added[i]) / 2
 	}
-	return md.md, ok
+
+	out := make(Metadata, metadataSize)
+	for k, v := range raw.md {
+		out[k] = copyOf(v)
+	}
+	for _, added := range raw.added {
+		if len(added)%2 == 1 {
+			panic(fmt.Sprintf("metadata: FromContext got an odd number of input pairs for metadata: %d", len(added)))
+		}
+
+		for i := 0; i < len(added); i += 2 {
+			out[added[i]] = append(out[added[i]], added[i+1])
+		}
+	}
+	return out, true
 }
 
-// MustContext returns metadata from the given context
-// returned metadata shoud not be modified or race condition happens
+// MustContext retrieves a deep copy of the metadata from the context and panics
+// if the metadata is not found.
 func MustContext(ctx context.Context) Metadata {
 	md, ok := FromContext(ctx)
 	if !ok {
@@ -82,98 +150,145 @@ func MustContext(ctx context.Context) Metadata {
 	return md
 }
 
-// NewContext creates a new context with the given metadata
-func NewContext(ctx context.Context, md Metadata) context.Context {
-	if ctx == nil {
-		ctx = context.Background()
-	}
-	return context.WithValue(ctx, mdKey{}, &rawMetadata{md})
-}
-
-// SetOutgoingContext modify outgoing context with given metadata
-func SetOutgoingContext(ctx context.Context, md Metadata) bool {
-	if ctx == nil {
-		return false
-	}
-	if omd, ok := ctx.Value(mdOutgoingKey{}).(*rawMetadata); ok {
-		omd.md = md
-		return true
-	}
-	return false
-}
-
-// SetIncomingContext modify incoming context with given metadata
-func SetIncomingContext(ctx context.Context, md Metadata) bool {
-	if ctx == nil {
-		return false
-	}
-	if omd, ok := ctx.Value(mdIncomingKey{}).(*rawMetadata); ok {
-		omd.md = md
-		return true
-	}
-	return false
-}
-
-// NewIncomingContext creates a new context with incoming metadata attached
-func NewIncomingContext(ctx context.Context, md Metadata) context.Context {
-	if ctx == nil {
-		ctx = context.Background()
-	}
-	return context.WithValue(ctx, mdIncomingKey{}, &rawMetadata{md})
-}
-
-// NewOutgoingContext creates a new context with outcoming metadata attached
-func NewOutgoingContext(ctx context.Context, md Metadata) context.Context {
-	if ctx == nil {
-		ctx = context.Background()
-	}
-	return context.WithValue(ctx, mdOutgoingKey{}, &rawMetadata{md})
-}
-
-// AppendOutgoingContext apends new md to context
-func AppendOutgoingContext(ctx context.Context, kv ...string) context.Context {
-	md, ok := Pairs(kv...)
+// FromIncomingContext retrieves a deep copy of the metadata from the context and returns it
+// with a boolean indicating if it was found.
+func FromIncomingContext(ctx context.Context) (Metadata, bool) {
+	raw, ok := ctx.Value(metadataIncomingKey{}).(rawMetadata)
 	if !ok {
-		return ctx
+		return nil, false
 	}
-	omd, ok := FromOutgoingContext(ctx)
-	if !ok {
-		return NewOutgoingContext(ctx, md)
+	metadataSize := len(raw.md)
+	for i := range raw.added {
+		metadataSize += len(raw.added[i]) / 2
 	}
-	for k, v := range md {
-		omd.Set(k, v)
+
+	out := make(Metadata, metadataSize)
+	for k, v := range raw.md {
+		out[k] = copyOf(v)
 	}
-	return ctx
+	for _, added := range raw.added {
+		if len(added)%2 == 1 {
+			panic(fmt.Sprintf("metadata: FromIncomingContext got an odd number of input pairs for metadata: %d", len(added)))
+		}
+
+		for i := 0; i < len(added); i += 2 {
+			out[added[i]] = append(out[added[i]], added[i+1])
+		}
+	}
+	return out, true
 }
 
-// AppendIncomingContext apends new md to context
-func AppendIncomingContext(ctx context.Context, kv ...string) context.Context {
-	md, ok := Pairs(kv...)
+// MustIncomingContext retrieves a deep copy of the metadata from the context and panics
+// if the metadata is not found.
+func MustIncomingContext(ctx context.Context) Metadata {
+	md, ok := FromIncomingContext(ctx)
 	if !ok {
-		return ctx
+		panic("missing metadata")
 	}
-	omd, ok := FromIncomingContext(ctx)
-	if !ok {
-		return NewIncomingContext(ctx, md)
-	}
-	for k, v := range md {
-		omd.Set(k, v)
-	}
-	return ctx
+	return md
 }
 
-// AppendContext apends new md to context
-func AppendContext(ctx context.Context, kv ...string) context.Context {
-	md, ok := Pairs(kv...)
+// FromOutgoingContext retrieves a deep copy of the metadata from the context and returns it
+// with a boolean indicating if it was found.
+func FromOutgoingContext(ctx context.Context) (Metadata, bool) {
+	raw, ok := ctx.Value(metadataOutgoingKey{}).(rawMetadata)
 	if !ok {
-		return ctx
+		return nil, false
 	}
-	omd, ok := FromContext(ctx)
-	if !ok {
-		return NewContext(ctx, md)
+
+	metadataSize := len(raw.md)
+	for i := range raw.added {
+		metadataSize += len(raw.added[i]) / 2
 	}
-	for k, v := range md {
-		omd.Set(k, v)
+
+	out := make(Metadata, metadataSize)
+	for k, v := range raw.md {
+		out[k] = copyOf(v)
 	}
-	return ctx
+	for _, added := range raw.added {
+		if len(added)%2 == 1 {
+			panic(fmt.Sprintf("metadata: FromOutgoingContext got an odd number of input pairs for metadata: %d", len(added)))
+		}
+
+		for i := 0; i < len(added); i += 2 {
+			out[added[i]] = append(out[added[i]], added[i+1])
+		}
+	}
+	return out, ok
+}
+
+// MustOutgoingContext retrieves a deep copy of the metadata from the context and panics
+// if the metadata is not found.
+func MustOutgoingContext(ctx context.Context) Metadata {
+	md, ok := FromOutgoingContext(ctx)
+	if !ok {
+		panic("missing metadata")
+	}
+	return md
+}
+
+// ValueFromCurrentContext retrieves a deep copy of the metadata for the given key
+// from the context, performing a case-insensitive search if needed. Returns nil if not found.
+func ValueFromCurrentContext(ctx context.Context, key string) []string {
+	md, ok := ctx.Value(metadataCurrentKey{}).(rawMetadata)
+	if !ok {
+		return nil
+	}
+
+	if v, ok := md.md[key]; ok {
+		return copyOf(v)
+	}
+	for k, v := range md.md {
+		// Case-insensitive comparison: Metadata is a map, and there's no guarantee
+		// that the Metadata attached to the context is created using our helper
+		// functions.
+		if strings.EqualFold(k, key) {
+			return copyOf(v)
+		}
+	}
+	return nil
+}
+
+// ValueFromIncomingContext retrieves a deep copy of the metadata for the given key
+// from the context, performing a case-insensitive search if needed. Returns nil if not found.
+func ValueFromIncomingContext(ctx context.Context, key string) []string {
+	raw, ok := ctx.Value(metadataIncomingKey{}).(rawMetadata)
+	if !ok {
+		return nil
+	}
+
+	if v, ok := raw.md[key]; ok {
+		return copyOf(v)
+	}
+	for k, v := range raw.md {
+		// Case-insensitive comparison: Metadata is a map, and there's no guarantee
+		// that the Metadata attached to the context is created using our helper
+		// functions.
+		if strings.EqualFold(k, key) {
+			return copyOf(v)
+		}
+	}
+	return nil
+}
+
+// ValueFromOutgoingContext retrieves a deep copy of the metadata for the given key
+// from the context, performing a case-insensitive search if needed. Returns nil if not found.
+func ValueFromOutgoingContext(ctx context.Context, key string) []string {
+	md, ok := ctx.Value(metadataOutgoingKey{}).(rawMetadata)
+	if !ok {
+		return nil
+	}
+
+	if v, ok := md.md[key]; ok {
+		return copyOf(v)
+	}
+	for k, v := range md.md {
+		// Case-insensitive comparison: Metadata is a map, and there's no guarantee
+		// that the Metadata attached to the context is created using our helper
+		// functions.
+		if strings.EqualFold(k, key) {
+			return copyOf(v)
+		}
+	}
+	return nil
 }

metadata/context_test.go

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

metadata/headers.go

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

metadata/helpers.go

@@ -0,0 +1,7 @@
+package metadata
+
+func copyOf(v []string) []string {
+	vals := make([]string, len(v))
+	copy(vals, v)
+	return vals
+}

metadata/iterator.go

@@ -0,0 +1,37 @@
+package metadata
+
+import "sort"
+
+type Iterator struct {
+	md   Metadata
+	keys []string
+	cur  int
+	cnt  int
+}
+
+// Next advances the iterator to the next element.
+func (iter *Iterator) Next(k *string, v *[]string) bool {
+	if iter.cur+1 > iter.cnt {
+		return false
+	}
+
+	if k != nil && v != nil {
+		*k = iter.keys[iter.cur]
+		vv := iter.md[*k]
+		*v = make([]string, len(vv))
+		copy(*v, vv)
+		iter.cur++
+	}
+	return true
+}
+
+// Iterator returns an iterator for iterating over metadata in sorted order.
+func (md Metadata) Iterator() *Iterator {
+	iter := &Iterator{md: md, cnt: len(md)}
+	iter.keys = make([]string, 0, iter.cnt)
+	for k := range md {
+		iter.keys = append(iter.keys, k)
+	}
+	sort.Strings(iter.keys)
+	return iter
+}

metadata/metadata.go

@@ -1,167 +1,160 @@
-// Package metadata is a way of defining message headers
 package metadata
 
 import (
+	"fmt"
 	"net/textproto"
-	"sort"
 	"strings"
 )
 
-var (
-	// HeaderTopic is the header name that contains topic name
-	HeaderTopic = "Micro-Topic"
-	// HeaderContentType specifies content type of message
-	HeaderContentType = "Content-Type"
-	// HeaderEndpoint specifies endpoint in service
-	HeaderEndpoint = "Micro-Endpoint"
-	// HeaderService specifies service
-	HeaderService = "Micro-Service"
-	// HeaderTimeout specifies timeout of operation
-	HeaderTimeout = "Micro-Timeout"
-	// HeaderAuthorization specifies Authorization header
-	HeaderAuthorization = "Authorization"
-	// HeaderXRequestID specifies request id
-	HeaderXRequestID = "X-Request-Id"
-)
-
-// Metadata is our way of representing request headers internally.
-// They're used at the RPC level and translate back and forth
-// from Transport headers.
-type Metadata map[string]string
-
-type rawMetadata struct {
-	md Metadata
-}
-
-// defaultMetadataSize used when need to init new Metadata
+// defaultMetadataSize is used when initializing new Metadata.
 var defaultMetadataSize = 2
 
-// Iterator used to iterate over metadata with order
-type Iterator struct {
-	md   Metadata
-	keys []string
-	cur  int
-	cnt  int
-}
+// Metadata maps keys to values. Use the New, NewWithMetadata and Pairs functions to create it.
+type Metadata map[string][]string
 
-// Next advance iterator to next element
-func (iter *Iterator) Next(k, v *string) bool {
-	if iter.cur+1 > iter.cnt {
-		return false
+// New creates a zero-value Metadata with the specified size.
+func New(l int) Metadata {
+	if l == 0 {
+		l = defaultMetadataSize
 	}
-
-	*k = iter.keys[iter.cur]
-	*v = iter.md[*k]
-	iter.cur++
-	return true
+	md := make(Metadata, l)
+	return md
 }
 
-// Iterator returns the itarator for metadata in sorted order
-func (md Metadata) Iterator() *Iterator {
-	iter := &Iterator{md: md, cnt: len(md)}
-	iter.keys = make([]string, 0, iter.cnt)
-	for k := range md {
-		iter.keys = append(iter.keys, k)
+// NewWithMetadata creates a Metadata from the provided key-value map.
+func NewWithMetadata(m map[string]string) Metadata {
+	md := make(Metadata, len(m))
+	for key, val := range m {
+		md[key] = append(md[key], val)
 	}
-	sort.Strings(iter.keys)
-	return iter
+	return md
 }
 
-func (md Metadata) MustGet(key string) string {
-	val, ok := md.Get(key)
-	if !ok {
-		panic("missing metadata key")
+// Pairs returns a Metadata formed from the key-value mapping. It panics if the length of kv is odd.
+func Pairs(kv ...string) Metadata {
+	if len(kv)%2 == 1 {
+		panic(fmt.Sprintf("metadata: Pairs got the odd number of input pairs for metadata: %d", len(kv)))
 	}
-	return val
+	md := make(Metadata, len(kv)/2)
+	for i := 0; i < len(kv); i += 2 {
+		md[kv[i]] = append(md[kv[i]], kv[i+1])
+	}
+	return md
 }
 
-// Get returns value from metadata by key
-func (md Metadata) Get(key string) (string, bool) {
-	// fast path
-	val, ok := md[key]
-	if !ok {
-		// slow path
-		val, ok = md[textproto.CanonicalMIMEHeaderKey(key)]
-		if !ok {
-			val, ok = md[strings.ToLower(key)]
+// Join combines multiple Metadatas into a single Metadata.
+// The order of values for each key is determined by the order in which the Metadatas are provided to Join.
+func Join(mds ...Metadata) Metadata {
+	out := Metadata{}
+	for _, md := range mds {
+		for k, v := range md {
+			out[k] = append(out[k], v...)
 		}
 	}
-	return val, ok
+	return out
 }
 
-// Set is used to store value in metadata
-func (md Metadata) Set(kv ...string) {
-	if len(kv)%2 == 1 {
-		kv = kv[:len(kv)-1]
-	}
-	for idx := 0; idx < len(kv); idx += 2 {
-		md[textproto.CanonicalMIMEHeaderKey(kv[idx])] = kv[idx+1]
+// Copy returns a deep copy of Metadata.
+func Copy(src Metadata) Metadata {
+	out := make(Metadata, len(src))
+	for k, v := range src {
+		out[k] = copyOf(v)
 	}
+	return out
 }
 
-// Del is used to remove value from metadata
-func (md Metadata) Del(keys ...string) {
-	for _, key := range keys {
-		// fast path
-		delete(md, key)
-		// slow path
-		delete(md, textproto.CanonicalMIMEHeaderKey(key))
-		// very slow path
-		delete(md, strings.ToLower(key))
-	}
-}
-
-// Copy makes a copy of the metadata
-func (md Metadata) CopyTo(dst Metadata) {
+// Copy returns a deep copy of Metadata.
+func (md Metadata) Copy() Metadata {
+	out := make(Metadata, len(md))
 	for k, v := range md {
-		dst[k] = v
+		out[k] = copyOf(v)
 	}
+	return out
 }
 
-// Copy makes a copy of the metadata
-func Copy(md Metadata, exclude ...string) Metadata {
-	nmd := New(len(md))
+// CopyTo performs a deep copy of Metadata to the out.
+func (md Metadata) CopyTo(out Metadata) {
 	for k, v := range md {
-		nmd[k] = v
+		out[k] = copyOf(v)
 	}
-	nmd.Del(exclude...)
-	return nmd
 }
 
-// New return new sized metadata
-func New(size int) Metadata {
-	if size == 0 {
-		size = defaultMetadataSize
-	}
-	return make(Metadata, size)
+// Len returns the number of items in Metadata.
+func (md Metadata) Len() int {
+	return len(md)
 }
 
-// Merge merges metadata to existing metadata, overwriting if specified
-func Merge(omd Metadata, mmd Metadata, overwrite bool) Metadata {
-	var ok bool
-	nmd := Copy(omd)
-	for key, val := range mmd {
-		_, ok = nmd[key]
-		switch {
-		case ok && !overwrite:
-			continue
-		case val != "":
-			nmd[key] = val
-		case ok && val == "":
-			nmd.Del(key)
-		}
+// AsMap returns a deep copy of Metadata as a map[string]string
+func (md Metadata) AsMap() map[string]string {
+	out := make(map[string]string, len(md))
+	for k, v := range md {
+		out[k] = strings.Join(v, ",")
 	}
-	return nmd
+	return out
 }
 
-// Pairs from which metadata created
-func Pairs(kv ...string) (Metadata, bool) {
-	if len(kv)%2 == 1 {
-		return nil, false
+// AsHTTP1 returns a deep copy of Metadata with keys converted to canonical MIME header key format.
+func (md Metadata) AsHTTP1() map[string][]string {
+	out := make(map[string][]string, len(md))
+	for k, v := range md {
+		out[textproto.CanonicalMIMEHeaderKey(k)] = copyOf(v)
+	}
+	return out
+}
+
+// AsHTTP2 returns a deep copy of Metadata with keys converted to lowercase.
+func (md Metadata) AsHTTP2() map[string][]string {
+	out := make(map[string][]string, len(md))
+	for k, v := range md {
+		out[strings.ToLower(k)] = copyOf(v)
+	}
+	return out
+}
+
+// Get retrieves the values for a given key, checking the key in three formats:
+// - exact case,
+// - lower case,
+// - canonical MIME header key format.
+func (md Metadata) Get(k string) []string {
+	v, ok := md[k]
+	if !ok {
+		v, ok = md[strings.ToLower(k)]
+	}
+	if !ok {
+		v = md[textproto.CanonicalMIMEHeaderKey(k)]
+	}
+	return v
+}
+
+// GetJoined retrieves the values for a given key and joins them into a single string, separated by commas.
+func (md Metadata) GetJoined(k string) string {
+	return strings.Join(md.Get(k), ",")
+}
+
+// Set assigns the values to the given key.
+func (md Metadata) Set(key string, vals ...string) {
+	if len(vals) == 0 {
+		return
+	}
+	md[key] = vals
+}
+
+// Append adds values to the existing values for the given key.
+func (md Metadata) Append(key string, vals ...string) {
+	if len(vals) == 0 {
+		return
+	}
+	md[key] = append(md[key], vals...)
+}
+
+// Del removes the values for the given keys k. It checks and removes the keys in the following formats:
+// - exact case,
+// - lower case,
+// - canonical MIME header key format.
+func (md Metadata) Del(k ...string) {
+	for i := range k {
+		delete(md, k[i])
+		delete(md, strings.ToLower(k[i]))
+		delete(md, textproto.CanonicalMIMEHeaderKey(k[i]))
 	}
-	md := New(len(kv) / 2)
-	for idx := 0; idx < len(kv); idx += 2 {
-		md[kv[idx]] = kv[idx+1]
-	}
-	return md, true
 }

metadata/metadata_test.go

@@ -5,11 +5,31 @@ import (
 	"testing"
 )
 
+func TesSet(t *testing.T) {
+	md := Pairs("key1", "val1", "key2", "val2")
+	md.Set("key1", "val2", "val3")
+	v := md.GetJoined("X-Request-Id")
+	if v != "val2, val3" {
+		t.Fatal("set not works")
+	}
+}
+
+/*
+func TestAppendOutgoingContextModify(t *testing.T) {
+	md := Pairs("key1", "val1")
+	ctx := NewOutgoingContext(context.TODO(), md)
+	nctx := AppendOutgoingContext(ctx, "key1", "val3", "key2", "val2")
+	_ = nctx
+	omd := MustOutgoingContext(nctx)
+	fmt.Printf("%#+v\n", omd)
+}
+*/
+
 func TestLowercase(t *testing.T) {
 	md := New(1)
-	md["x-request-id"] = "12345"
-	v, ok := md.Get("X-Request-Id")
-	if !ok || v == "" {
+	md["x-request-id"] = []string{"12345"}
+	v := md.GetJoined("X-Request-Id")
+	if v == "" {
 		t.Fatalf("metadata invalid %#+v", md)
 	}
 }
@@ -36,50 +56,13 @@ func TestMultipleUsage(t *testing.T) {
 	_ = omd
 }
 
-func TestMetadataSetMultiple(t *testing.T) {
-	md := New(4)
-	md.Set("key1", "val1", "key2", "val2", "key3")
-
-	if v, ok := md.Get("key1"); !ok || v != "val1" {
-		t.Fatalf("invalid kv %#+v", md)
-	}
-	if v, ok := md.Get("key2"); !ok || v != "val2" {
-		t.Fatalf("invalid kv %#+v", md)
-	}
-	if _, ok := md.Get("key3"); ok {
-		t.Fatalf("invalid kv %#+v", md)
-	}
-}
-
-func TestAppend(t *testing.T) {
-	ctx := context.Background()
-	ctx = AppendIncomingContext(ctx, "key1", "val1", "key2", "val2")
-	md, ok := FromIncomingContext(ctx)
-	if !ok {
-		t.Fatal("metadata empty")
-	}
-	if _, ok := md.Get("key1"); !ok {
-		t.Fatal("key1 not found")
-	}
-}
-
 func TestPairs(t *testing.T) {
-	md, ok := Pairs("key1", "val1", "key2", "val2")
-	if !ok {
-		t.Fatal("odd number of kv")
-	}
-	if _, ok = md.Get("key1"); !ok {
+	md := Pairs("key1", "val1", "key2", "val2")
+	if v := md.Get("key1"); v == nil {
 		t.Fatal("key1 not found")
 	}
 }
 
-func testCtx(ctx context.Context) {
-	md := New(2)
-	md.Set("Key1", "Val1_new")
-	md.Set("Key3", "Val3")
-	SetOutgoingContext(ctx, md)
-}
-
 func TestPassing(t *testing.T) {
 	ctx := context.TODO()
 	md1 := New(2)
@@ -87,70 +70,63 @@ func TestPassing(t *testing.T) {
 	md1.Set("Key2", "Val2")
 
 	ctx = NewIncomingContext(ctx, md1)
-	testCtx(ctx)
+
 	_, ok := FromOutgoingContext(ctx)
 	if ok {
 		t.Fatalf("create outgoing context")
 	}
 
-	ctx = NewOutgoingContext(ctx, New(1))
-	testCtx(ctx)
+	ctx = NewOutgoingContext(ctx, md1)
+
 	md, ok := FromOutgoingContext(ctx)
 	if !ok {
 		t.Fatalf("missing metadata from outgoing context")
 	}
-	if v, ok := md.Get("Key1"); !ok || v != "Val1_new" {
+	if v := md.Get("Key1"); v == nil || v[0] != "Val1" {
 		t.Fatalf("invalid metadata value %#+v", md)
 	}
 }
 
-func TestMerge(t *testing.T) {
-	omd := Metadata{
-		"key1": "val1",
-	}
-	mmd := Metadata{
-		"key2": "val2",
-	}
-
-	nmd := Merge(omd, mmd, true)
-	if len(nmd) != 2 {
-		t.Fatalf("merge failed: %v", nmd)
-	}
-}
-
-func TestIterator(_ *testing.T) {
-	md := Metadata{
-		"1Last":   "last",
-		"2First":  "first",
-		"3Second": "second",
-	}
+func TestIterator(t *testing.T) {
+	md := Pairs(
+		"1Last", "last",
+		"2First", "first",
+		"3Second", "second",
+	)
 
 	iter := md.Iterator()
-	var k, v string
-
+	var k string
+	var v []string
+	chk := New(3)
 	for iter.Next(&k, &v) {
-		// fmt.Printf("k: %s, v: %s\n", k, v)
+		chk[k] = v
+	}
+
+	for k, v := range chk {
+		if cv, ok := md[k]; !ok || len(cv) != len(v) || cv[0] != v[0] {
+			t.Fatalf("XXXX %#+v %#+v", chk, md)
+		}
 	}
 }
 
 func TestMedataCanonicalKey(t *testing.T) {
 	md := New(1)
 	md.Set("x-request-id", "12345")
-	v, ok := md.Get("x-request-id")
-	if !ok {
+	v := md.GetJoined("x-request-id")
+	if v == "" {
 		t.Fatalf("failed to get x-request-id")
 	} else if v != "12345" {
 		t.Fatalf("invalid metadata value: %s != %s", "12345", v)
 	}
 
-	v, ok = md.Get("X-Request-Id")
-	if !ok {
+	v = md.GetJoined("X-Request-Id")
+	if v == "" {
 		t.Fatalf("failed to get x-request-id")
 	} else if v != "12345" {
 		t.Fatalf("invalid metadata value: %s != %s", "12345", v)
 	}
-	v, ok = md.Get("X-Request-ID")
-	if !ok {
+	v = md.GetJoined("X-Request-ID")
+	if v == "" {
 		t.Fatalf("failed to get x-request-id")
 	} else if v != "12345" {
 		t.Fatalf("invalid metadata value: %s != %s", "12345", v)
@@ -162,8 +138,8 @@ func TestMetadataSet(t *testing.T) {
 
 	md.Set("Key", "val")
 
-	val, ok := md.Get("Key")
-	if !ok {
+	val := md.GetJoined("Key")
+	if val == "" {
 		t.Fatal("key Key not found")
 	}
 	if val != "val" {
@@ -173,36 +149,27 @@ func TestMetadataSet(t *testing.T) {
 
 func TestMetadataDelete(t *testing.T) {
 	md := Metadata{
-		"Foo": "bar",
-		"Baz": "empty",
+		"Foo": []string{"bar"},
+		"Baz": []string{"empty"},
 	}
 
 	md.Del("Baz")
-	_, ok := md.Get("Baz")
-	if ok {
+	v := md.Get("Baz")
+	if v != nil {
 		t.Fatal("key Baz not deleted")
 	}
 }
 
-func TestNilContext(t *testing.T) {
-	var ctx context.Context
-
-	_, ok := FromContext(ctx)
-	if ok {
-		t.Fatal("nil context")
-	}
-}
-
 func TestMetadataCopy(t *testing.T) {
 	md := Metadata{
-		"Foo": "bar",
-		"Bar": "baz",
+		"Foo": []string{"bar"},
+		"Bar": []string{"baz"},
 	}
 
 	cp := Copy(md)
 
 	for k, v := range md {
-		if cv := cp[k]; cv != v {
+		if cv := cp[k]; cv[0] != v[0] {
 			t.Fatalf("Got %s:%s for %s:%s", k, cv, k, v)
 		}
 	}
@@ -210,7 +177,7 @@ func TestMetadataCopy(t *testing.T) {
 
 func TestMetadataContext(t *testing.T) {
 	md := Metadata{
-		"Foo": "bar",
+		"Foo": []string{"bar"},
 	}
 
 	ctx := NewContext(context.TODO(), md)
@@ -220,7 +187,7 @@ func TestMetadataContext(t *testing.T) {
 		t.Errorf("Unexpected error retrieving metadata, got %t", ok)
 	}
 
-	if emd["Foo"] != md["Foo"] {
+	if emd["Foo"][0] != md["Foo"][0] {
 		t.Errorf("Expected key: %s val: %s, got key: %s val: %s", "Foo", md["Foo"], "Foo", emd["Foo"])
 	}
 
@@ -229,13 +196,74 @@ func TestMetadataContext(t *testing.T) {
 	}
 }
 
-func TestCopy(t *testing.T) {
-	md := New(2)
-	md.Set("key1", "val1", "key2", "val2")
-	nmd := Copy(md, "key2")
-	if len(nmd) != 1 {
-		t.Fatal("Copy exclude not works")
-	} else if nmd["Key1"] != "val1" {
-		t.Fatal("Copy exclude not works")
+func TestFromContext(t *testing.T) {
+	ctx := context.WithValue(context.TODO(), metadataCurrentKey{}, rawMetadata{md: New(0)})
+
+	c, ok := FromContext(ctx)
+	if c == nil || !ok {
+		t.Fatal("FromContext not works")
+	}
+}
+
+func TestNewContext(t *testing.T) {
+	ctx := NewContext(context.TODO(), New(0))
+
+	c, ok := FromContext(ctx)
+	if c == nil || !ok {
+		t.Fatal("NewContext not works")
+	}
+}
+
+func TestFromIncomingContext(t *testing.T) {
+	ctx := context.WithValue(context.TODO(), metadataIncomingKey{}, rawMetadata{md: New(0)})
+
+	c, ok := FromIncomingContext(ctx)
+	if c == nil || !ok {
+		t.Fatal("FromIncomingContext not works")
+	}
+}
+
+func TestFromOutgoingContext(t *testing.T) {
+	ctx := context.WithValue(context.TODO(), metadataOutgoingKey{}, rawMetadata{md: New(0)})
+
+	c, ok := FromOutgoingContext(ctx)
+	if c == nil || !ok {
+		t.Fatal("FromOutgoingContext not works")
+	}
+}
+
+func TestNewIncomingContext(t *testing.T) {
+	md := New(1)
+	md.Set("key", "val")
+	ctx := NewIncomingContext(context.TODO(), md)
+
+	c, ok := FromIncomingContext(ctx)
+	if c == nil || !ok {
+		t.Fatal("NewIncomingContext not works")
+	}
+}
+
+func TestNewOutgoingContext(t *testing.T) {
+	md := New(1)
+	md.Set("key", "val")
+	ctx := NewOutgoingContext(context.TODO(), md)
+
+	c, ok := FromOutgoingContext(ctx)
+	if c == nil || !ok {
+		t.Fatal("NewOutgoingContext not works")
+	}
+}
+
+func TestAppendOutgoingContext(t *testing.T) {
+	md := New(1)
+	md.Set("key1", "val1")
+	ctx := AppendOutgoingContext(context.TODO(), "key2", "val2")
+
+	nmd, ok := FromOutgoingContext(ctx)
+	if nmd == nil || !ok {
+		t.Fatal("AppendOutgoingContext not works")
+	}
+	if v := nmd.GetJoined("key2"); v != "val2" {
+		t.Fatal("AppendOutgoingContext not works")
 	}
 }

meter/meter.go

@@ -4,8 +4,8 @@ package meter
 import (
 	"io"
 	"sort"
-	"strconv"
 	"strings"
+	"sync"
 	"time"
 )
 
@@ -59,6 +59,8 @@ type Meter interface {
 	Options() Options
 	// String return meter type
 	String() string
+	// Unregister metric name and drop all data
+	Unregister(name string, labels ...string) bool
 }
 
 // Counter is a counter
@@ -117,6 +119,39 @@ func BuildLabels(labels ...string) []string {
 	return labels
 }
 
+var spool = newStringsPool(500)
+
+type stringsPool struct {
+	p *sync.Pool
+	c int
+}
+
+func newStringsPool(size int) *stringsPool {
+	p := &stringsPool{c: size}
+	p.p = &sync.Pool{
+		New: func() interface{} {
+			return &strings.Builder{}
+		},
+	}
+	return p
+}
+
+func (p *stringsPool) Cap() int {
+	return p.c
+}
+
+func (p *stringsPool) Get() *strings.Builder {
+	return p.p.Get().(*strings.Builder)
+}
+
+func (p *stringsPool) Put(b *strings.Builder) {
+	if b.Cap() > p.c {
+		return
+	}
+	b.Reset()
+	p.p.Put(b)
+}
+
 // BuildName used to combine metric with labels.
 // If labels count is odd, drop last element
 func BuildName(name string, labels ...string) string {
@@ -125,8 +160,6 @@ func BuildName(name string, labels ...string) string {
 	}
 
 	if len(labels) > 2 {
-		sort.Sort(byKey(labels))
-
 		idx := 0
 		for {
 			if labels[idx] == labels[idx+2] {
@@ -141,7 +174,9 @@ func BuildName(name string, labels ...string) string {
 		}
 	}
 
-	var b strings.Builder
+	b := spool.Get()
+	defer spool.Put(b)
+
 	_, _ = b.WriteString(name)
 	_, _ = b.WriteRune('{')
 	for idx := 0; idx < len(labels); idx += 2 {
@@ -149,8 +184,9 @@ func BuildName(name string, labels ...string) string {
 			_, _ = b.WriteRune(',')
 		}
 		_, _ = b.WriteString(labels[idx])
-		_, _ = b.WriteString(`=`)
-		_, _ = b.WriteString(strconv.Quote(labels[idx+1]))
+		_, _ = b.WriteString(`="`)
+		_, _ = b.WriteString(labels[idx+1])
+		_, _ = b.WriteRune('"')
 	}
 	_, _ = b.WriteRune('}')
 

meter/meter_test.go

@@ -50,11 +50,12 @@ func TestBuildName(t *testing.T) {
 	data := map[string][]string{
 		`my_metric{firstlabel="value2",zerolabel="value3"}`: {
 			"my_metric",
-			"zerolabel", "value3", "firstlabel", "value2",
+			"firstlabel", "value2",
+			"zerolabel", "value3",
 		},
 		`my_metric{broker="broker2",register="mdns",server="tcp"}`: {
 			"my_metric",
-			"broker", "broker1", "broker", "broker2", "server", "http", "server", "tcp", "register", "mdns",
+			"broker", "broker1", "broker", "broker2", "register", "mdns", "server", "http", "server", "tcp",
 		},
 		`my_metric{aaa="aaa"}`: {
 			"my_metric",

meter/noop.go

@@ -28,6 +28,10 @@ func (r *noopMeter) Name() string {
 	return r.opts.Name
 }
 
+func (r *noopMeter) Unregister(name string, labels ...string) bool {
+	return true
+}
+
 // Init initialize options
 func (r *noopMeter) Init(opts ...Option) error {
 	for _, o := range opts {

micro.go

@@ -3,21 +3,21 @@ package micro
 import (
 	"reflect"
 
-	"go.unistack.org/micro/v3/broker"
-	"go.unistack.org/micro/v3/client"
-	"go.unistack.org/micro/v3/codec"
-	"go.unistack.org/micro/v3/flow"
-	"go.unistack.org/micro/v3/fsm"
-	"go.unistack.org/micro/v3/logger"
-	"go.unistack.org/micro/v3/meter"
-	"go.unistack.org/micro/v3/register"
-	"go.unistack.org/micro/v3/resolver"
-	"go.unistack.org/micro/v3/router"
-	"go.unistack.org/micro/v3/selector"
-	"go.unistack.org/micro/v3/server"
-	"go.unistack.org/micro/v3/store"
-	"go.unistack.org/micro/v3/sync"
-	"go.unistack.org/micro/v3/tracer"
+	"go.unistack.org/micro/v4/broker"
+	"go.unistack.org/micro/v4/client"
+	"go.unistack.org/micro/v4/codec"
+	"go.unistack.org/micro/v4/flow"
+	"go.unistack.org/micro/v4/fsm"
+	"go.unistack.org/micro/v4/logger"
+	"go.unistack.org/micro/v4/meter"
+	"go.unistack.org/micro/v4/register"
+	"go.unistack.org/micro/v4/resolver"
+	"go.unistack.org/micro/v4/router"
+	"go.unistack.org/micro/v4/selector"
+	"go.unistack.org/micro/v4/server"
+	"go.unistack.org/micro/v4/store"
+	"go.unistack.org/micro/v4/sync"
+	"go.unistack.org/micro/v4/tracer"
 )
 
 func As(b any, target any) bool {

micro_test.go

@@ -6,8 +6,9 @@ import (
 	"reflect"
 	"testing"
 
-	"go.unistack.org/micro/v3/broker"
-	"go.unistack.org/micro/v3/fsm"
+	"go.unistack.org/micro/v4/broker"
+	"go.unistack.org/micro/v4/fsm"
+	"go.unistack.org/micro/v4/metadata"
 )
 
 func TestAs(t *testing.T) {
@@ -61,6 +62,8 @@ func TestAs(t *testing.T) {
 	}
 }
 
+var _ broker.Broker = (*bro)(nil)
+
 type bro struct {
 	name string
 }
@@ -87,23 +90,18 @@ func (p *bro) Connect(_ context.Context) error { return nil }
 // Disconnect disconnect from broker
 func (p *bro) Disconnect(_ context.Context) error { return nil }
 
-// Publish message, msg can be single broker.Message or []broker.Message
-func (p *bro) Publish(_ context.Context, _ string, _ *broker.Message, _ ...broker.PublishOption) error {
-	return nil
-}
-
-// BatchPublish messages to broker with multiple topics
-func (p *bro) BatchPublish(_ context.Context, _ []*broker.Message, _ ...broker.PublishOption) error {
-	return nil
-}
-
-// BatchSubscribe subscribes to topic messages via handler
-func (p *bro) BatchSubscribe(_ context.Context, _ string, _ broker.BatchHandler, _ ...broker.SubscribeOption) (broker.Subscriber, error) {
+// NewMessage creates new message
+func (p *bro) NewMessage(_ context.Context, _ metadata.Metadata, _ interface{}, _ ...broker.MessageOption) (broker.Message, error) {
 	return nil, nil
 }
 
+// Publish message, msg can be single broker.Message or []broker.Message
+func (p *bro) Publish(_ context.Context, _ string, _ ...broker.Message) error {
+	return nil
+}
+
 // Subscribe subscribes to topic message via handler
-func (p *bro) Subscribe(_ context.Context, _ string, _ broker.Handler, _ ...broker.SubscribeOption) (broker.Subscriber, error) {
+func (p *bro) Subscribe(_ context.Context, _ string, _ interface{}, _ ...broker.SubscribeOption) (broker.Subscriber, error) {
 	return nil, nil
 }
 

network/network.go

@@ -1,55 +0,0 @@
-// Package network is for creating internetworks
-package network
-
-import (
-	"go.unistack.org/micro/v3/client"
-	"go.unistack.org/micro/v3/server"
-)
-
-// Error is network node errors
-type Error interface {
-	// Count is current count of errors
-	Count() int
-	// Msg is last error message
-	Msg() string
-}
-
-// Status is node status
-type Status interface {
-	// Error reports error status
-	Error() Error
-}
-
-// Node is network node
-type Node interface {
-	// Id is node id
-	Id() string
-	// Address is node bind address
-	Address() string
-	// Peers returns node peers
-	Peers() []Node
-	// Network is the network node is in
-	Network() Network
-	// Status returns node status
-	Status() Status
-}
-
-// Network is micro network
-type Network interface {
-	// Node is network node
-	Node
-	// Initialise options
-	Init(...Option) error
-	// Options returns the network options
-	Options() Options
-	// Name of the network
-	Name() string
-	// Connect starts the resolver and tunnel server
-	Connect() error
-	// Close stops the tunnel and resolving
-	Close() error
-	// Client is micro client
-	Client() client.Client
-	// Server is micro server
-	Server() server.Server
-}

network/options.go

@@ -1,135 +0,0 @@
-package network
-
-import (
-	"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
-type Option func(*Options)
-
-// Options configure network
-type Options struct {
-	// Router used for routing
-	Router router.Router
-	// Proxy holds the proxy
-	Proxy proxy.Proxy
-	// Logger used for logging
-	Logger logger.Logger
-	// Meter used for metrics
-	Meter meter.Meter
-	// Tracer used for tracing
-	Tracer tracer.Tracer
-	// Tunnel used for transfer data
-	Tunnel tunnel.Tunnel
-	// ID of the node
-	ID string
-	// Name of the network
-	Name string
-	// Address to bind to
-	Address string
-	// Advertise sets the address to advertise
-	Advertise string
-	// Nodes is a list of nodes to connect to
-	Nodes []string
-}
-
-// ID sets the id of the network node
-func ID(id string) Option {
-	return func(o *Options) {
-		o.ID = id
-	}
-}
-
-// Name sets the network name
-func Name(n string) Option {
-	return func(o *Options) {
-		o.Name = n
-	}
-}
-
-// Address sets the network address
-func Address(a string) Option {
-	return func(o *Options) {
-		o.Address = a
-	}
-}
-
-// Advertise sets the address to advertise
-func Advertise(a string) Option {
-	return func(o *Options) {
-		o.Advertise = a
-	}
-}
-
-// Nodes is a list of nodes to connect to
-func Nodes(n ...string) Option {
-	return func(o *Options) {
-		o.Nodes = n
-	}
-}
-
-// Tunnel sets the network tunnel
-func Tunnel(t tunnel.Tunnel) Option {
-	return func(o *Options) {
-		o.Tunnel = t
-	}
-}
-
-// Router sets the network router
-func Router(r router.Router) Option {
-	return func(o *Options) {
-		o.Router = r
-	}
-}
-
-// Proxy sets the network proxy
-func Proxy(p proxy.Proxy) Option {
-	return func(o *Options) {
-		o.Proxy = p
-	}
-}
-
-// Logger sets the network logger
-func Logger(l logger.Logger) Option {
-	return func(o *Options) {
-		o.Logger = l
-	}
-}
-
-// Meter sets the meter
-func Meter(m meter.Meter) Option {
-	return func(o *Options) {
-		o.Meter = m
-	}
-}
-
-// Tracer to be used for tracing
-func Tracer(t tracer.Tracer) Option {
-	return func(o *Options) {
-		o.Tracer = t
-	}
-}
-
-// NewOptions returns network default options
-func NewOptions(opts ...Option) Options {
-	options := Options{
-		ID:      id.MustNew(),
-		Name:    "go.micro",
-		Address: ":0",
-		Logger:  logger.DefaultLogger,
-		Meter:   meter.DefaultMeter,
-		Tracer:  tracer.DefaultTracer,
-	}
-
-	for _, o := range opts {
-		o(&options)
-	}
-
-	return options
-}

network/transport/context.go

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

network/transport/memory.go

@@ -1,258 +0,0 @@
-package transport
-
-import (
-	"context"
-	"errors"
-	"fmt"
-	"net"
-	"sync"
-	"time"
-
-	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 {
-	ctx     context.Context
-	recv    chan *Message
-	exit    chan bool
-	lexit   chan bool
-	send    chan *Message
-	local   string
-	remote  string
-	timeout time.Duration
-	sync.RWMutex
-}
-
-type memoryClient struct {
-	*memorySocket
-	opts DialOptions
-}
-
-type memoryListener struct {
-	lopts ListenOptions
-	ctx   context.Context
-	exit  chan bool
-	conn  chan *memorySocket
-	addr  string
-	topts Options
-	sync.RWMutex
-}
-
-type memoryTransport struct {
-	listeners map[string]*memoryListener
-	opts      Options
-	sync.RWMutex
-}
-
-func (ms *memorySocket) Recv(m *Message) error {
-	ms.RLock()
-	defer ms.RUnlock()
-
-	ctx := ms.ctx
-	if ms.timeout > 0 {
-		var cancel context.CancelFunc
-		ctx, cancel = context.WithTimeout(ms.ctx, ms.timeout)
-		defer cancel()
-	}
-
-	select {
-	case <-ctx.Done():
-		return ctx.Err()
-	case <-ms.exit:
-		return errors.New("connection closed")
-	case <-ms.lexit:
-		return errors.New("server connection closed")
-	case cm := <-ms.recv:
-		*m = *cm
-	}
-	return nil
-}
-
-func (ms *memorySocket) Local() string {
-	return ms.local
-}
-
-func (ms *memorySocket) Remote() string {
-	return ms.remote
-}
-
-func (ms *memorySocket) Send(m *Message) error {
-	ms.RLock()
-	defer ms.RUnlock()
-
-	ctx := ms.ctx
-	if ms.timeout > 0 {
-		var cancel context.CancelFunc
-		ctx, cancel = context.WithTimeout(ms.ctx, ms.timeout)
-		defer cancel()
-	}
-
-	select {
-	case <-ctx.Done():
-		return ctx.Err()
-	case <-ms.exit:
-		return errors.New("connection closed")
-	case <-ms.lexit:
-		return errors.New("server connection closed")
-	case ms.send <- m:
-	}
-	return nil
-}
-
-func (ms *memorySocket) Close() error {
-	ms.Lock()
-	defer ms.Unlock()
-	select {
-	case <-ms.exit:
-		return nil
-	default:
-		close(ms.exit)
-	}
-	return nil
-}
-
-func (m *memoryListener) Addr() string {
-	return m.addr
-}
-
-func (m *memoryListener) Close() error {
-	m.Lock()
-	defer m.Unlock()
-	select {
-	case <-m.exit:
-		return nil
-	default:
-		close(m.exit)
-	}
-	return nil
-}
-
-func (m *memoryListener) Accept(fn func(Socket)) error {
-	for {
-		select {
-		case <-m.exit:
-			return nil
-		case c := <-m.conn:
-			go fn(&memorySocket{
-				lexit:   c.lexit,
-				exit:    c.exit,
-				send:    c.recv,
-				recv:    c.send,
-				local:   c.Remote(),
-				remote:  c.Local(),
-				timeout: m.topts.Timeout,
-				ctx:     m.topts.Context,
-			})
-		}
-	}
-}
-
-func (m *memoryTransport) Dial(ctx context.Context, addr string, opts ...DialOption) (Client, error) {
-	m.RLock()
-	defer m.RUnlock()
-
-	listener, ok := m.listeners[addr]
-	if !ok {
-		return nil, errors.New("could not dial " + addr)
-	}
-
-	options := NewDialOptions(opts...)
-
-	client := &memoryClient{
-		&memorySocket{
-			send:    make(chan *Message),
-			recv:    make(chan *Message),
-			exit:    make(chan bool),
-			lexit:   listener.exit,
-			local:   addr,
-			remote:  addr,
-			timeout: m.opts.Timeout,
-			ctx:     m.opts.Context,
-		},
-		options,
-	}
-
-	// pseudo connect
-	select {
-	case <-listener.exit:
-		return nil, errors.New("connection error")
-	case listener.conn <- client.memorySocket:
-	}
-
-	return client, nil
-}
-
-func (m *memoryTransport) Listen(ctx context.Context, addr string, opts ...ListenOption) (Listener, error) {
-	m.Lock()
-	defer m.Unlock()
-
-	options := NewListenOptions(opts...)
-
-	host, port, err := net.SplitHostPort(addr)
-	if err != nil {
-		return nil, err
-	}
-
-	addr, err = maddr.Extract(host)
-	if err != nil {
-		return nil, err
-	}
-
-	// if zero port then randomly assign one
-	if len(port) > 0 && port == "0" {
-		var rng rand.Rand
-		i := rng.Intn(20000)
-		port = fmt.Sprintf("%d", 10000+i)
-	}
-
-	// set addr with port
-	addr = mnet.HostPort(addr, port)
-
-	if _, ok := m.listeners[addr]; ok {
-		return nil, errors.New("already listening on " + addr)
-	}
-
-	listener := &memoryListener{
-		lopts: options,
-		topts: m.opts,
-		addr:  addr,
-		conn:  make(chan *memorySocket),
-		exit:  make(chan bool),
-		ctx:   m.opts.Context,
-	}
-
-	m.listeners[addr] = listener
-
-	return listener, nil
-}
-
-func (m *memoryTransport) Init(opts ...Option) error {
-	for _, o := range opts {
-		o(&m.opts)
-	}
-	return nil
-}
-
-func (m *memoryTransport) Options() Options {
-	return m.opts
-}
-
-func (m *memoryTransport) String() string {
-	return "memory"
-}
-
-func (m *memoryTransport) Name() string {
-	return m.opts.Name
-}
-
-// NewTransport returns new memory transport with options
-func NewTransport(opts ...Option) Transport {
-	options := NewOptions(opts...)
-
-	return &memoryTransport{
-		opts:      options,
-		listeners: make(map[string]*memoryListener),
-	}
-}

network/transport/memory_test.go

@@ -1,100 +0,0 @@
-package transport
-
-import (
-	"context"
-	"os"
-	"testing"
-)
-
-func TestMemoryTransport(t *testing.T) {
-	tr := NewTransport()
-	ctx := context.Background()
-	// bind / listen
-	l, err := tr.Listen(ctx, "127.0.0.1:8080")
-	if err != nil {
-		t.Fatalf("Unexpected error listening %v", err)
-	}
-	defer l.Close()
-
-	cherr := make(chan error, 1)
-	// accept
-	go func() {
-		if nerr := l.Accept(func(sock Socket) {
-			for {
-				var m Message
-				if rerr := sock.Recv(&m); rerr != nil {
-					cherr <- rerr
-					return
-				}
-				if len(os.Getenv("INTEGRATION_TESTS")) == 0 {
-					t.Logf("Server Received %s", string(m.Body))
-				}
-				if cerr := sock.Send(&Message{
-					Body: []byte(`pong`),
-				}); cerr != nil {
-					cherr <- cerr
-					return
-				}
-			}
-		}); nerr != nil {
-			cherr <- err
-		}
-	}()
-
-	// dial
-	c, err := tr.Dial(ctx, "127.0.0.1:8080")
-	if err != nil {
-		t.Fatalf("Unexpected error dialing %v", err)
-	}
-	defer c.Close()
-
-	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))
-			}
-		}
-	}
-}
-
-func TestListener(t *testing.T) {
-	tr := NewTransport()
-	ctx := context.Background()
-	// bind / listen on random port
-	l, err := tr.Listen(ctx, ":0")
-	if err != nil {
-		t.Fatalf("Unexpected error listening %v", err)
-	}
-	defer l.Close()
-
-	// try again
-	l2, err := tr.Listen(ctx, ":0")
-	if err != nil {
-		t.Fatalf("Unexpected error listening %v", err)
-	}
-	defer l2.Close()
-
-	// now make sure it still fails
-	l3, err := tr.Listen(ctx, ":8080")
-	if err != nil {
-		t.Fatalf("Unexpected error listening %v", err)
-	}
-	defer l3.Close()
-
-	if _, err := tr.Listen(ctx, ":8080"); err == nil {
-		t.Fatal("Expected error binding to :8080 got nil")
-	}
-}

network/transport/options.go

@@ -1,175 +0,0 @@
-package transport
-
-import (
-	"context"
-	"crypto/tls"
-	"time"
-
-	"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
-type Options struct {
-	// Meter used for metrics
-	Meter meter.Meter
-	// Tracer used for tracing
-	Tracer tracer.Tracer
-	// Codec used for marshal/unmarshal messages
-	Codec codec.Codec
-	// Logger used for logging
-	Logger logger.Logger
-	// Context holds external options
-	Context context.Context
-	// TLSConfig holds tls.TLSConfig options
-	TLSConfig *tls.Config
-	// Name holds the transport name
-	Name string
-	// Addrs holds the transport addrs
-	Addrs []string
-	// Timeout holds the timeout
-	Timeout time.Duration
-}
-
-// NewOptions returns new options
-func NewOptions(opts ...Option) Options {
-	options := Options{
-		Logger:  logger.DefaultLogger,
-		Meter:   meter.DefaultMeter,
-		Tracer:  tracer.DefaultTracer,
-		Context: context.Background(),
-	}
-
-	for _, o := range opts {
-		o(&options)
-	}
-
-	return options
-}
-
-// DialOptions struct
-type DialOptions struct {
-	// Context holds the external options
-	Context context.Context
-	// Timeout holds the timeout
-	Timeout time.Duration
-	// Stream flag
-	Stream bool
-}
-
-// NewDialOptions returns new DialOptions
-func NewDialOptions(opts ...DialOption) DialOptions {
-	options := DialOptions{
-		Timeout: DefaultDialTimeout,
-		Context: context.Background(),
-	}
-
-	for _, o := range opts {
-		o(&options)
-	}
-
-	return options
-}
-
-// ListenOptions struct
-type ListenOptions struct {
-	// TODO: add tls options when listening
-	// Currently set in global options
-	// Context holds the external options
-	Context context.Context
-	// TLSConfig holds the *tls.Config options
-	TLSConfig *tls.Config
-}
-
-// NewListenOptions returns new ListenOptions
-func NewListenOptions(opts ...ListenOption) ListenOptions {
-	options := ListenOptions{
-		Context: context.Background(),
-	}
-
-	for _, o := range opts {
-		o(&options)
-	}
-
-	return options
-}
-
-// Addrs to use for transport
-func Addrs(addrs ...string) Option {
-	return func(o *Options) {
-		o.Addrs = addrs
-	}
-}
-
-// Logger sets the logger
-func Logger(l logger.Logger) Option {
-	return func(o *Options) {
-		o.Logger = l
-	}
-}
-
-// Meter sets the meter
-func Meter(m meter.Meter) Option {
-	return func(o *Options) {
-		o.Meter = m
-	}
-}
-
-// Context sets the context
-func Context(ctx context.Context) Option {
-	return func(o *Options) {
-		o.Context = ctx
-	}
-}
-
-// Codec sets the codec used for encoding where the transport
-// does not support message headers
-func Codec(c codec.Codec) Option {
-	return func(o *Options) {
-		o.Codec = c
-	}
-}
-
-// Timeout sets the timeout for Send/Recv execution
-func Timeout(t time.Duration) Option {
-	return func(o *Options) {
-		o.Timeout = t
-	}
-}
-
-// TLSConfig to be used for the transport.
-func TLSConfig(t *tls.Config) Option {
-	return func(o *Options) {
-		o.TLSConfig = t
-	}
-}
-
-// WithStream indicates whether this is a streaming connection
-func WithStream() DialOption {
-	return func(o *DialOptions) {
-		o.Stream = true
-	}
-}
-
-// WithTimeout used when dialling the remote side
-func WithTimeout(d time.Duration) DialOption {
-	return func(o *DialOptions) {
-		o.Timeout = d
-	}
-}
-
-// Tracer to be used for tracing
-func Tracer(t tracer.Tracer) Option {
-	return func(o *Options) {
-		o.Tracer = t
-	}
-}
-
-// Name sets the name
-func Name(n string) Option {
-	return func(o *Options) {
-		o.Name = n
-	}
-}

network/transport/transport.go

@@ -1,63 +0,0 @@
-// Package transport is an interface for synchronous connection based communication
-package transport
-
-import (
-	"context"
-	"time"
-
-	"go.unistack.org/micro/v3/metadata"
-)
-
-var (
-	// DefaultTransport is the global default transport
-	DefaultTransport = NewTransport()
-	// DefaultDialTimeout the default dial timeout
-	DefaultDialTimeout = time.Second * 5
-)
-
-// Transport is an interface which is used for communication between
-// services. It uses connection based socket send/recv semantics and
-// has various implementations; http, grpc, quic.
-type Transport interface {
-	Init(...Option) error
-	Options() Options
-	Dial(ctx context.Context, addr string, opts ...DialOption) (Client, error)
-	Listen(ctx context.Context, addr string, opts ...ListenOption) (Listener, error)
-	String() string
-}
-
-// Message is used to transfer data
-type Message struct {
-	Header metadata.Metadata
-	Body   []byte
-}
-
-// Socket bastraction interface
-type Socket interface {
-	Recv(*Message) error
-	Send(*Message) error
-	Close() error
-	Local() string
-	Remote() string
-}
-
-// Client is the socket owner
-type Client interface {
-	Socket
-}
-
-// Listener is the interface for stream oriented messaging
-type Listener interface {
-	Addr() string
-	Close() error
-	Accept(func(Socket)) error
-}
-
-// Option is the option signature
-type Option func(*Options)
-
-// DialOption is the option signature
-type DialOption func(*DialOptions)
-
-// ListenOption is the option signature
-type ListenOption func(*ListenOptions)

network/tunnel/broker/broker.go

@@ -1,372 +0,0 @@
-// Package broker is a tunnel broker
-package broker
-
-import (
-	"context"
-	"fmt"
-
-	"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 {
-	tunnel tunnel.Tunnel
-	opts   broker.Options
-}
-
-type tunSubscriber struct {
-	listener tunnel.Listener
-	handler  broker.Handler
-	closed   chan bool
-	topic    string
-	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
-}
-
-// used to access tunnel from options context
-type (
-	tunnelKey  struct{}
-	tunnelAddr struct{}
-)
-
-func (t *tunBroker) Live() bool {
-	return true
-}
-
-func (t *tunBroker) Ready() bool {
-	return true
-}
-
-func (t *tunBroker) Health() bool {
-	return true
-}
-
-func (t *tunBroker) Init(opts ...broker.Option) error {
-	for _, o := range opts {
-		o(&t.opts)
-	}
-	return nil
-}
-
-func (t *tunBroker) Name() string {
-	return t.opts.Name
-}
-
-func (t *tunBroker) Options() broker.Options {
-	return t.opts
-}
-
-func (t *tunBroker) Address() string {
-	return t.tunnel.Address()
-}
-
-func (t *tunBroker) Connect(ctx context.Context) error {
-	return t.tunnel.Connect(ctx)
-}
-
-func (t *tunBroker) Disconnect(ctx context.Context) error {
-	return t.tunnel.Close(ctx)
-}
-
-func (t *tunBroker) BatchPublish(ctx context.Context, msgs []*broker.Message, _ ...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, _ ...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
-	c, err := t.tunnel.Dial(ctx, topic, tunnel.DialMode(tunnel.Multicast))
-	if err != nil {
-		return err
-	}
-	defer c.Close()
-
-	return c.Send(&transport.Message{
-		Header: m.Header,
-		Body:   m.Body,
-	})
-}
-
-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 {
-		return nil, err
-	}
-
-	tunSub := &tunSubscriber{
-		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) 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.DefaultLogger.V(logger.ErrorLevel) {
-				logger.DefaultLogger.Error(t.opts.Context, err.Error(), err)
-			}
-			if err = c.Close(); err != nil {
-				if logger.DefaultLogger.V(logger.ErrorLevel) {
-					logger.DefaultLogger.Error(t.opts.Context, err.Error(), err)
-				}
-			}
-			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
-		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.DefaultLogger.V(logger.ErrorLevel) {
-				logger.DefaultLogger.Error(t.opts.Context, err.Error(), err)
-			}
-			if err = c.Close(); err != nil {
-				if logger.DefaultLogger.V(logger.ErrorLevel) {
-					logger.DefaultLogger.Error(t.opts.Context, err.Error(), err)
-				}
-			}
-			continue
-		}
-
-		// close the connection
-		c.Close()
-
-		// handle the message
-		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()
-	}
-}
-
-func (t *tunSubscriber) Options() broker.SubscribeOptions {
-	return t.opts
-}
-
-func (t *tunSubscriber) Topic() string {
-	return t.topic
-}
-
-func (t *tunSubscriber) Unsubscribe(ctx context.Context) error {
-	select {
-	case <-t.closed:
-		return nil
-	default:
-		close(t.closed)
-		return t.listener.Close()
-	}
-}
-
-func (t *tunEvent) Topic() string {
-	return t.topic
-}
-
-func (t *tunEvent) Message() *broker.Message {
-	return t.message
-}
-
-func (t *tunEvent) Ack() error {
-	return nil
-}
-
-func (t *tunEvent) Error() error {
-	return t.err
-}
-
-func (t *tunEvent) SetError(err error) {
-	t.err = err
-}
-
-func (t *tunEvent) Context() context.Context {
-	return context.TODO()
-}
-
-// NewBroker returns new tunnel broker
-func NewBroker(opts ...broker.Option) (broker.Broker, error) {
-	options := broker.NewOptions(opts...)
-
-	t, ok := options.Context.Value(tunnelKey{}).(tunnel.Tunnel)
-	if !ok {
-		return nil, fmt.Errorf("tunnel not set")
-	}
-
-	a, ok := options.Context.Value(tunnelAddr{}).(string)
-	if ok {
-		// initialise address
-		if err := t.Init(tunnel.Address(a)); err != nil {
-			return nil, err
-		}
-	}
-
-	if len(options.Addrs) > 0 {
-		// initialise nodes
-		if err := t.Init(tunnel.Nodes(options.Addrs...)); err != nil {
-			return nil, err
-		}
-	}
-
-	return &tunBroker{
-		opts:   options,
-		tunnel: t,
-	}, nil
-}
-
-// WithAddress sets the tunnel address
-func WithAddress(a string) broker.Option {
-	return func(o *broker.Options) {
-		if o.Context == nil {
-			o.Context = context.Background()
-		}
-		o.Context = context.WithValue(o.Context, tunnelAddr{}, a)
-	}
-}
-
-// WithTunnel sets the internal tunnel
-func WithTunnel(t tunnel.Tunnel) broker.Option {
-	return func(o *broker.Options) {
-		if o.Context == nil {
-			o.Context = context.Background()
-		}
-		o.Context = context.WithValue(o.Context, tunnelKey{}, t)
-	}
-}

network/tunnel/options.go

@@ -1,192 +0,0 @@
-package tunnel
-
-import (
-	"time"
-
-	"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 (
-	// DefaultAddress is default tunnel bind address
-	DefaultAddress = ":0"
-	// DefaultToken the shared default token
-	DefaultToken = "go.micro.tunnel"
-)
-
-// Option func signature
-type Option func(*Options)
-
-// Options provides network configuration options
-type Options struct {
-	// Logger used for logging
-	Logger logger.Logger
-	// Meter used for metrics
-	Meter meter.Meter
-	// Tracer used for tracing
-	Tracer tracer.Tracer
-	// Transport used for communication
-	Transport transport.Transport
-	// Token the shared auth token
-	Token string
-	// Name holds the tunnel name
-	Name string
-	// ID holds the tunnel id
-	ID string
-	// Address holds the tunnel address
-	Address string
-	// Nodes holds the tunnel nodes
-	Nodes []string
-}
-
-// DialOption func
-type DialOption func(*DialOptions)
-
-// DialOptions provides dial options
-type DialOptions struct {
-	// Link specifies the link to use
-	Link string
-	// specify mode of the session
-	Mode Mode
-	// Wait for connection to be accepted
-	Wait bool
-	// the dial timeout
-	Timeout time.Duration
-}
-
-// ListenOption func
-type ListenOption func(*ListenOptions)
-
-// ListenOptions provides listen options
-type ListenOptions struct {
-	// Mode specify mode of the session
-	Mode Mode
-	// Timeout the read timeout
-	Timeout time.Duration
-}
-
-// ID sets the tunnel id
-func ID(id string) Option {
-	return func(o *Options) {
-		o.ID = id
-	}
-}
-
-// Logger sets the logger
-func Logger(l logger.Logger) Option {
-	return func(o *Options) {
-		o.Logger = l
-	}
-}
-
-// Meter sets the meter
-func Meter(m meter.Meter) Option {
-	return func(o *Options) {
-		o.Meter = m
-	}
-}
-
-// Address sets the tunnel address
-func Address(a string) Option {
-	return func(o *Options) {
-		o.Address = a
-	}
-}
-
-// Nodes specify remote network nodes
-func Nodes(n ...string) Option {
-	return func(o *Options) {
-		o.Nodes = n
-	}
-}
-
-// Token sets the shared token for auth
-func Token(t string) Option {
-	return func(o *Options) {
-		o.Token = t
-	}
-}
-
-// Transport listens for incoming connections
-func Transport(t transport.Transport) Option {
-	return func(o *Options) {
-		o.Transport = t
-	}
-}
-
-// ListenMode option
-func ListenMode(m Mode) ListenOption {
-	return func(o *ListenOptions) {
-		o.Mode = m
-	}
-}
-
-// ListenTimeout for reads and writes on the listener session
-func ListenTimeout(t time.Duration) ListenOption {
-	return func(o *ListenOptions) {
-		o.Timeout = t
-	}
-}
-
-// DialMode multicast sets the multicast option to send only to those mapped
-func DialMode(m Mode) DialOption {
-	return func(o *DialOptions) {
-		o.Mode = m
-	}
-}
-
-// DialTimeout sets the dial timeout of the connection
-func DialTimeout(t time.Duration) DialOption {
-	return func(o *DialOptions) {
-		o.Timeout = t
-	}
-}
-
-// DialLink specifies the link to pin this connection to.
-// This is not applicable if the multicast option is set.
-func DialLink(id string) DialOption {
-	return func(o *DialOptions) {
-		o.Link = id
-	}
-}
-
-// DialWait specifies whether to wait for the connection
-// to be accepted before returning the session
-func DialWait(b bool) DialOption {
-	return func(o *DialOptions) {
-		o.Wait = b
-	}
-}
-
-// NewOptions returns router default options with filled values
-func NewOptions(opts ...Option) Options {
-	options := Options{
-		ID:      id.MustNew(),
-		Address: DefaultAddress,
-		Token:   DefaultToken,
-		Logger:  logger.DefaultLogger,
-		Meter:   meter.DefaultMeter,
-		Tracer:  tracer.DefaultTracer,
-	}
-	for _, o := range opts {
-		o(&options)
-	}
-	return options
-}
-
-// Tracer to be used for tracing
-func Tracer(t tracer.Tracer) Option {
-	return func(o *Options) {
-		o.Tracer = t
-	}
-}
-
-// Name sets the name
-func Name(n string) Option {
-	return func(o *Options) {
-		o.Name = n
-	}
-}

network/tunnel/transport/listener.go

@@ -1,30 +0,0 @@
-package transport
-
-import (
-	"go.unistack.org/micro/v3/network/transport"
-	"go.unistack.org/micro/v3/network/tunnel"
-)
-
-type tunListener struct {
-	l tunnel.Listener
-}
-
-func (t *tunListener) Addr() string {
-	return t.l.Channel()
-}
-
-func (t *tunListener) Close() error {
-	return t.l.Close()
-}
-
-func (t *tunListener) Accept(fn func(socket transport.Socket)) error {
-	for {
-		// accept connection
-		c, err := t.l.Accept()
-		if err != nil {
-			return err
-		}
-		// execute the function
-		go fn(c)
-	}
-}

network/tunnel/transport/transport.go

@@ -1,113 +0,0 @@
-// Package transport provides a tunnel transport
-package transport
-
-import (
-	"context"
-	"fmt"
-
-	"go.unistack.org/micro/v3/network/transport"
-	"go.unistack.org/micro/v3/network/tunnel"
-)
-
-type tunTransport struct {
-	tunnel  tunnel.Tunnel
-	options transport.Options
-}
-
-type tunnelKey struct{}
-
-type transportKey struct{}
-
-func (t *tunTransport) Init(opts ...transport.Option) error {
-	for _, o := range opts {
-		o(&t.options)
-	}
-
-	// close the existing tunnel
-	if t.tunnel != nil {
-		t.tunnel.Close(context.TODO())
-	}
-
-	// get the tunnel
-	tun, ok := t.options.Context.Value(tunnelKey{}).(tunnel.Tunnel)
-	if !ok {
-		return fmt.Errorf("tunnel not set")
-	}
-
-	// get the transport
-	tr, ok := t.options.Context.Value(transportKey{}).(transport.Transport)
-	if ok {
-		_ = tun.Init(tunnel.Transport(tr))
-	}
-
-	// set the tunnel
-	t.tunnel = tun
-
-	return nil
-}
-
-func (t *tunTransport) Dial(ctx context.Context, addr string, opts ...transport.DialOption) (transport.Client, error) {
-	if err := t.tunnel.Connect(ctx); err != nil {
-		return nil, err
-	}
-
-	c, err := t.tunnel.Dial(ctx, addr)
-	if err != nil {
-		return nil, err
-	}
-
-	return c, nil
-}
-
-func (t *tunTransport) Listen(ctx context.Context, addr string, opts ...transport.ListenOption) (transport.Listener, error) {
-	if err := t.tunnel.Connect(ctx); err != nil {
-		return nil, err
-	}
-
-	l, err := t.tunnel.Listen(ctx, addr)
-	if err != nil {
-		return nil, err
-	}
-
-	return &tunListener{l}, nil
-}
-
-func (t *tunTransport) Options() transport.Options {
-	return t.options
-}
-
-func (t *tunTransport) String() string {
-	return "tunnel"
-}
-
-// NewTransport honours the initialiser used in
-func NewTransport(opts ...transport.Option) transport.Transport {
-	t := &tunTransport{
-		options: transport.Options{},
-	}
-
-	// initialise
-	// t.Init(opts...)
-
-	return t
-}
-
-// WithTunnel sets the internal tunnel
-func WithTunnel(t tunnel.Tunnel) transport.Option {
-	return func(o *transport.Options) {
-		if o.Context == nil {
-			o.Context = context.Background()
-		}
-		o.Context = context.WithValue(o.Context, tunnelKey{}, t)
-	}
-}
-
-// WithTransport sets the internal transport
-func WithTransport(t transport.Transport) transport.Option {
-	return func(o *transport.Options) {
-		if o.Context == nil {
-			o.Context = context.Background()
-		}
-		o.Context = context.WithValue(o.Context, transportKey{}, t)
-	}
-}

network/tunnel/tunnel.go

@@ -1,106 +0,0 @@
-// Package tunnel provides gre network tunnelling
-package tunnel
-
-import (
-	"context"
-	"errors"
-	"time"
-
-	"go.unistack.org/micro/v3/network/transport"
-)
-
-// DefaultTunnel contains default tunnel implementation
-var DefaultTunnel Tunnel
-
-const (
-	// Unicast send over one link
-	Unicast Mode = iota
-	// Multicast send to all channel listeners
-	Multicast
-	// Broadcast send to all links
-	Broadcast
-)
-
-var (
-	// DefaultDialTimeout is the dial timeout if none is specified
-	DefaultDialTimeout = time.Second * 5
-	// ErrDialTimeout is returned by a call to Dial where the timeout occurs
-	ErrDialTimeout = errors.New("dial timeout")
-	// ErrDiscoverChan is returned when we failed to receive the "announce" back from a discovery
-	ErrDiscoverChan = errors.New("failed to discover channel")
-	// ErrLinkNotFound is returned when a link is specified at dial time and does not exist
-	ErrLinkNotFound = errors.New("link not found")
-	// ErrLinkDisconnected is returned when a link we attempt to send to is disconnected
-	ErrLinkDisconnected = errors.New("link not connected")
-	// ErrLinkLoopback is returned when attempting to send an outbound message over loopback link
-	ErrLinkLoopback = errors.New("link is loopback")
-	// ErrLinkRemote is returned when attempting to send a loopback message over remote link
-	ErrLinkRemote = errors.New("link is remote")
-	// ErrReadTimeout is a timeout on session.Recv
-	ErrReadTimeout = errors.New("read timeout")
-	// ErrDecryptingData is for when theres a nonce error
-	ErrDecryptingData = errors.New("error decrypting data")
-)
-
-// Mode of the session
-type Mode uint8
-
-// Tunnel creates a gre tunnel on top of the micro/transport.
-// It establishes multiple streams using the Micro-Tunnel-Channel header
-// and Micro-Tunnel-Session header. The tunnel id is a hash of
-// the address being requested.
-type Tunnel interface {
-	// Init initializes tunnel with options
-	Init(opts ...Option) error
-	// Address returns the address the tunnel is listening on
-	Address() string
-	// Connect connects the tunnel
-	Connect(ctx context.Context) error
-	// Close closes the tunnel
-	Close(ctx context.Context) error
-	// Links returns all the links the tunnel is connected to
-	Links() []Link
-	// Dial allows a client to connect to a channel
-	Dial(ctx context.Context, channel string, opts ...DialOption) (Session, error)
-	// Listen allows to accept connections on a channel
-	Listen(ctx context.Context, channel string, opts ...ListenOption) (Listener, error)
-	// String returns the name of the tunnel implementation
-	String() string
-}
-
-// Link represents internal links to the tunnel
-type Link interface {
-	// Id returns the link unique Id
-	Id() string
-	// Delay is the current load on the link (lower is better)
-	Delay() int64
-	// Length returns the roundtrip time as nanoseconds (lower is better)
-	Length() int64
-	// Current transfer rate as bits per second (lower is better)
-	Rate() float64
-	// Is this a loopback link
-	Loopback() bool
-	// State of the link: connected/closed/error
-	State() string
-	// honours transport socket
-	transport.Socket
-}
-
-// Listener provides similar constructs to the transport.Listener
-type Listener interface {
-	Accept() (Session, error)
-	Channel() string
-	Close() error
-}
-
-// Session is a unique session created when dialling or accepting connections on the tunnel
-type Session interface {
-	// The unique session id
-	Id() string
-	// The channel name
-	Channel() string
-	// The link the session is on
-	Link() string
-	// a transport socket
-	transport.Socket
-}

options.go

@@ -5,17 +5,17 @@ import (
 	"fmt"
 	"time"
 
-	"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"
+	"go.unistack.org/micro/v4/broker"
+	"go.unistack.org/micro/v4/client"
+	"go.unistack.org/micro/v4/config"
+	"go.unistack.org/micro/v4/logger"
+	"go.unistack.org/micro/v4/metadata"
+	"go.unistack.org/micro/v4/meter"
+	"go.unistack.org/micro/v4/register"
+	"go.unistack.org/micro/v4/router"
+	"go.unistack.org/micro/v4/server"
+	"go.unistack.org/micro/v4/store"
+	"go.unistack.org/micro/v4/tracer"
 )
 
 // Options for micro service

options/options.go

@@ -0,0 +1,222 @@
+package options
+
+import (
+	"reflect"
+	"strings"
+	"time"
+
+	"github.com/spf13/cast"
+	mreflect "go.unistack.org/micro/v4/util/reflect"
+)
+
+// Options interface must be used by all options
+type Validator interface {
+	// Validate returns nil, if all options are correct,
+	// otherwise returns an error explaining the mistake
+	Validate() error
+}
+
+// Option func signature
+type Option func(interface{}) error
+
+// Apply assign options to struct src
+func Apply(src interface{}, opts ...Option) error {
+	for _, opt := range opts {
+		if err := opt(src); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// SetValueByPath set src struct field to val dst via path
+func SetValueByPath(src interface{}, dst interface{}, path string) error {
+	var err error
+
+	switch v := dst.(type) {
+	case []interface{}:
+		if len(v) == 1 {
+			dst = v[0]
+		}
+	}
+
+	var sv reflect.Value
+	switch t := src.(type) {
+	case reflect.Value:
+		sv = t
+	default:
+		sv = reflect.ValueOf(src)
+	}
+
+	parts := strings.Split(path, ".")
+
+	for _, p := range parts {
+
+		if sv.Kind() == reflect.Ptr {
+			sv = sv.Elem()
+		}
+		if sv.Kind() != reflect.Struct {
+			return mreflect.ErrInvalidStruct
+		}
+
+		typ := sv.Type()
+		for idx := 0; idx < typ.NumField(); idx++ {
+			fld := typ.Field(idx)
+			val := sv.Field(idx)
+
+			/*
+				if len(fld.PkgPath) != 0 {
+					continue
+				}
+			*/
+
+			if fld.Anonymous {
+				if len(parts) == 1 && val.Kind() == reflect.Struct {
+					if err = SetValueByPath(val, dst, p); err != nil {
+						return err
+					}
+				}
+			}
+
+			if fld.Name != p && !strings.EqualFold(strings.ToLower(fld.Name), strings.ToLower(p)) {
+				continue
+			}
+
+			switch val.Interface().(type) {
+			case []time.Duration:
+				dst, err = cast.ToDurationSliceE(dst)
+				if err != nil {
+					return err
+				}
+				reflect.Copy(val, reflect.ValueOf(dst))
+				return nil
+			case time.Duration:
+				dst, err = cast.ToDurationE(dst)
+				if err != nil {
+					return err
+				}
+				val.Set(reflect.ValueOf(dst))
+				return nil
+			case time.Time:
+				dst, err = cast.ToTimeE(dst)
+				if err != nil {
+					return err
+				}
+				val.Set(reflect.ValueOf(dst))
+				return nil
+			}
+
+			switch val.Kind() {
+			case reflect.Map:
+				if val.IsZero() {
+					val.Set(reflect.MakeMap(val.Type()))
+				}
+
+				return setMap(val.Interface(), dst)
+			case reflect.Array, reflect.Slice:
+				switch val.Type().Elem().Kind() {
+				case reflect.Bool:
+					dst, err = cast.ToBoolSliceE(dst)
+				case reflect.String:
+					dst, err = cast.ToStringSliceE(dst)
+				case reflect.Float32:
+					dst, err = toFloat32SliceE(dst)
+				case reflect.Float64:
+					dst, err = toFloat64SliceE(dst)
+				case reflect.Int8:
+					dst, err = toInt8SliceE(dst)
+				case reflect.Int:
+					dst, err = cast.ToIntSliceE(dst)
+				case reflect.Int16:
+					dst, err = toInt16SliceE(dst)
+				case reflect.Int32:
+					dst, err = toInt32SliceE(dst)
+				case reflect.Int64:
+					dst, err = toInt64SliceE(dst)
+				case reflect.Uint8:
+					dst, err = toUint8SliceE(dst)
+				case reflect.Uint:
+					dst, err = toUintSliceE(dst)
+				case reflect.Uint16:
+					dst, err = toUint16SliceE(dst)
+				case reflect.Uint32:
+					dst, err = toUint32SliceE(dst)
+				case reflect.Uint64:
+					dst, err = toUint64SliceE(dst)
+				}
+				if err != nil {
+					return err
+				}
+				if val.Kind() == reflect.Slice {
+					val.Set(reflect.ValueOf(dst))
+				} else {
+					reflect.Copy(val, reflect.ValueOf(dst))
+				}
+				return nil
+			case reflect.Float32:
+				dst, err = toFloat32SliceE(dst)
+			case reflect.Float64:
+				dst, err = toFloat64SliceE(dst)
+			case reflect.Bool:
+				dst, err = cast.ToBoolE(dst)
+			case reflect.String:
+				dst, err = cast.ToStringE(dst)
+			case reflect.Int8:
+				dst, err = cast.ToInt8E(dst)
+			case reflect.Int:
+				dst, err = cast.ToIntE(dst)
+			case reflect.Int16:
+				dst, err = cast.ToInt16E(dst)
+			case reflect.Int32:
+				dst, err = cast.ToInt32E(dst)
+			case reflect.Int64:
+				dst, err = cast.ToInt64E(dst)
+			case reflect.Uint8:
+				dst, err = cast.ToUint8E(dst)
+			case reflect.Uint:
+				dst, err = cast.ToUintE(dst)
+			case reflect.Uint16:
+				dst, err = cast.ToUint16E(dst)
+			case reflect.Uint32:
+				dst, err = cast.ToUint32E(dst)
+			case reflect.Uint64:
+				dst, err = cast.ToUint64E(dst)
+			default:
+			}
+			if err != nil {
+				return err
+			}
+			val.Set(reflect.ValueOf(dst))
+		}
+	}
+
+	return nil
+}
+
+// NewOption create new option with name
+func NewOption(name string) func(...interface{}) Option {
+	return func(dst ...interface{}) Option {
+		return func(src interface{}) error {
+			return SetValueByPath(src, dst, name)
+		}
+	}
+}
+
+var (
+	Address   = NewOption("Address")
+	Name      = NewOption("Name")
+	Broker    = NewOption("Broker")
+	Logger    = NewOption("Logger")
+	Meter     = NewOption("Meter")
+	Tracer    = NewOption("Tracer")
+	Store     = NewOption("Store")
+	Register  = NewOption("Register")
+	Router    = NewOption("Router")
+	Codec     = NewOption("Codec")
+	Codecs    = NewOption("Codecs")
+	Client    = NewOption("Client")
+	Context   = NewOption("Context")
+	TLSConfig = NewOption("TLSConfig")
+	Metadata  = NewOption("Metadata")
+	Timeout   = NewOption("Timeout")
+)

options/options_test.go

@@ -0,0 +1,181 @@
+package options_test
+
+import (
+	"crypto/tls"
+	"sync"
+	"testing"
+
+	"go.unistack.org/micro/v4/options"
+)
+
+type codec interface {
+	Marshal(v interface{}, opts ...options.Option) ([]byte, error)
+	Unmarshal(b []byte, v interface{}, opts ...options.Option) error
+	String() string
+}
+
+func TestCodecs(t *testing.T) {
+	type s struct {
+		Codecs map[string]codec
+	}
+
+	wg := &sync.WaitGroup{}
+	tc := &tls.Config{InsecureSkipVerify: true}
+	opts := []options.Option{
+		options.NewOption("Codecs")(wg),
+		options.NewOption("TLSConfig")(tc),
+	}
+
+	src := &s{}
+
+	if err := options.Apply(src, opts...); err != nil {
+		t.Fatal(err)
+	}
+}
+
+func TestSpecial(t *testing.T) {
+	type s struct {
+		Wait      *sync.WaitGroup
+		TLSConfig *tls.Config
+	}
+
+	wg := &sync.WaitGroup{}
+	tc := &tls.Config{InsecureSkipVerify: true}
+	opts := []options.Option{
+		options.NewOption("Wait")(wg),
+		options.NewOption("TLSConfig")(tc),
+	}
+
+	src := &s{}
+
+	if err := options.Apply(src, opts...); err != nil {
+		t.Fatal(err)
+	}
+
+	if src.Wait == nil {
+		t.Fatalf("failed to set Wait %#+v", src)
+	}
+
+	if src.TLSConfig == nil {
+		t.Fatalf("failed to set TLSConfig %#+v", src)
+	}
+
+	if src.TLSConfig.InsecureSkipVerify != true {
+		t.Fatalf("failed to set TLSConfig %#+v", src)
+	}
+}
+
+func TestNested(t *testing.T) {
+	type server struct {
+		Address []string
+	}
+	type ownserver struct {
+		server
+		OwnField string
+	}
+
+	opts := []options.Option{
+		options.Address("host:port"),
+		options.NewOption("OwnField")("fieldval"),
+	}
+
+	src := &ownserver{}
+
+	if err := options.Apply(src, opts...); err != nil {
+		t.Fatal(err)
+	}
+
+	if src.Address[0] != "host:port" {
+		t.Fatalf("failed to set Address %#+v", src)
+	}
+
+	if src.OwnField != "fieldval" {
+		t.Fatalf("failed to set OwnField %#+v", src)
+	}
+}
+
+func TestAddress(t *testing.T) {
+	type s struct {
+		Address []string
+	}
+
+	opts := []options.Option{options.Address("host:port")}
+
+	src := &s{}
+
+	if err := options.Apply(src, opts...); err != nil {
+		t.Fatal(err)
+	}
+
+	if src.Address[0] != "host:port" {
+		t.Fatalf("failed to set Address %#+v", src)
+	}
+}
+
+func TestNewOption(t *testing.T) {
+	type s struct {
+		Address []string
+	}
+
+	opts := []options.Option{options.NewOption("Address")("host1:port1", "host2:port2")}
+
+	src := &s{}
+
+	if err := options.Apply(src, opts...); err != nil {
+		t.Fatal(err)
+	}
+
+	if src.Address[0] != "host1:port1" {
+		t.Fatalf("failed to set Address %#+v", src)
+	}
+	if src.Address[1] != "host2:port2" {
+		t.Fatalf("failed to set Address %#+v", src)
+	}
+}
+
+func TestArray(t *testing.T) {
+	type s struct {
+		Address [1]string
+	}
+
+	opts := []options.Option{options.NewOption("Address")("host:port", "host1:port1")}
+
+	src := &s{}
+
+	if err := options.Apply(src, opts...); err != nil {
+		t.Fatal(err)
+	}
+
+	if src.Address[0] != "host:port" {
+		t.Fatalf("failed to set Address %#+v", src)
+	}
+}
+
+func TestMap(t *testing.T) {
+	type s struct {
+		Metadata map[string]string
+	}
+
+	opts := []options.Option{
+		options.NewOption("Metadata")("key1", "val1"),
+		options.NewOption("Metadata")(map[string]string{"key2": "val2"}),
+	}
+
+	src := &s{}
+
+	if err := options.Apply(src, opts...); err != nil {
+		t.Fatal(err)
+	}
+
+	if len(src.Metadata) != 2 {
+		t.Fatalf("failed to set Metadata %#+v", src)
+	}
+
+	if src.Metadata["key1"] != "val1" {
+		t.Fatalf("failed to set Metadata %#+v", src)
+	}
+
+	if src.Metadata["key2"] != "val2" {
+		t.Fatalf("failed to set Metadata %#+v", src)
+	}
+}

options/util.go

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

profiler/http/http.go

@@ -7,12 +7,12 @@ import (
 	"net/http/pprof"
 	"sync"
 
-	profile "go.unistack.org/micro/v3/profiler"
+	profile "go.unistack.org/micro/v4/profiler"
 )
 
 type httpProfile struct {
-	server *http.Server
-	sync.Mutex
+	server  *http.Server
+	mu      sync.Mutex
 	running bool
 }
 
@@ -21,8 +21,8 @@ var DefaultAddress = ":6060"
 
 // Start the profiler
 func (h *httpProfile) Start() error {
-	h.Lock()
-	defer h.Unlock()
+	h.mu.Lock()
+	defer h.mu.Unlock()
 
 	if h.running {
 		return nil
@@ -30,9 +30,9 @@ func (h *httpProfile) Start() error {
 
 	go func() {
 		if err := h.server.ListenAndServe(); err != nil {
-			h.Lock()
+			h.mu.Lock()
 			h.running = false
-			h.Unlock()
+			h.mu.Unlock()
 		}
 	}()
 
@@ -43,8 +43,8 @@ func (h *httpProfile) Start() error {
 
 // Stop the profiler
 func (h *httpProfile) Stop() error {
-	h.Lock()
-	defer h.Unlock()
+	h.mu.Lock()
+	defer h.mu.Unlock()
 
 	if !h.running {
 		return nil

profiler/pprof/pprof.go

@@ -9,7 +9,7 @@ import (
 	"sync"
 	"time"
 
-	profile "go.unistack.org/micro/v3/profiler"
+	profile "go.unistack.org/micro/v4/profiler"
 )
 
 type profiler struct {
@@ -17,7 +17,7 @@ type profiler struct {
 	cpuFile *os.File
 	memFile *os.File
 	opts    profile.Options
-	sync.Mutex
+	mu      sync.Mutex
 	running bool
 }
 
@@ -39,8 +39,8 @@ func (p *profiler) writeHeap(f *os.File) {
 }
 
 func (p *profiler) Start() error {
-	p.Lock()
-	defer p.Unlock()
+	p.mu.Lock()
+	defer p.mu.Unlock()
 
 	if p.running {
 		return nil
@@ -86,8 +86,8 @@ func (p *profiler) Start() error {
 }
 
 func (p *profiler) Stop() error {
-	p.Lock()
-	defer p.Unlock()
+	p.mu.Lock()
+	defer p.mu.Unlock()
 
 	select {
 	case <-p.exit:

proxy/options.go

@@ -1,98 +0,0 @@
-// Package proxy is a transparent proxy built on the micro/server
-package proxy
-
-import (
-	"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
-type Options struct {
-	// Tracer used for tracing
-	Tracer tracer.Tracer
-	// Client for communication
-	Client client.Client
-	// Router for routing
-	Router router.Router
-	// Logger used for logging
-	Logger logger.Logger
-	// Meter used for metrics
-	Meter meter.Meter
-	// Links holds the communication links
-	Links map[string]client.Client
-	// Endpoint holds the destination address
-	Endpoint string
-}
-
-// Option func signature
-type Option func(o *Options)
-
-// NewOptions returns new options struct that filled by opts
-func NewOptions(opts ...Option) Options {
-	options := Options{
-		Logger: logger.DefaultLogger,
-		Meter:  meter.DefaultMeter,
-		Tracer: tracer.DefaultTracer,
-	}
-
-	for _, o := range opts {
-		o(&options)
-	}
-
-	return options
-}
-
-// WithEndpoint sets a proxy endpoint
-func WithEndpoint(e string) Option {
-	return func(o *Options) {
-		o.Endpoint = e
-	}
-}
-
-// WithClient sets the client
-func WithClient(c client.Client) Option {
-	return func(o *Options) {
-		o.Client = c
-	}
-}
-
-// WithRouter specifies the router to use
-func WithRouter(r router.Router) Option {
-	return func(o *Options) {
-		o.Router = r
-	}
-}
-
-// WithLogger specifies the logger to use
-func WithLogger(l logger.Logger) Option {
-	return func(o *Options) {
-		o.Logger = l
-	}
-}
-
-// WithMeter specifies the meter to use
-func WithMeter(m meter.Meter) Option {
-	return func(o *Options) {
-		o.Meter = m
-	}
-}
-
-// WithLink sets a link for outbound requests
-func WithLink(name string, c client.Client) Option {
-	return func(o *Options) {
-		if o.Links == nil {
-			o.Links = make(map[string]client.Client)
-		}
-		o.Links[name] = c
-	}
-}
-
-// Tracer to be used for tracing
-func Tracer(t tracer.Tracer) Option {
-	return func(o *Options) {
-		o.Tracer = t
-	}
-}

proxy/proxy.go

@@ -1,21 +0,0 @@
-// Package proxy is a transparent proxy built on the micro/server
-package proxy
-
-import (
-	"context"
-
-	"go.unistack.org/micro/v3/server"
-)
-
-// DefaultEndpoint holds default proxy address
-var DefaultEndpoint = "localhost:9090"
-
-// Proxy can be used as a proxy server for micro services
-type Proxy interface {
-	// ProcessMessage handles inbound messages
-	ProcessMessage(context.Context, server.Message) error
-	// ServeRequest handles inbound requests
-	ServeRequest(context.Context, server.Request, server.Response) error
-	// Name of the proxy protocol
-	String() string
-}

register/memory/memory.go

@@ -6,9 +6,10 @@ import (
 	"sync"
 	"time"
 
-	"go.unistack.org/micro/v3/logger"
-	"go.unistack.org/micro/v3/register"
-	"go.unistack.org/micro/v3/util/id"
+	"go.unistack.org/micro/v4/logger"
+	"go.unistack.org/micro/v4/metadata"
+	"go.unistack.org/micro/v4/register"
+	"go.unistack.org/micro/v4/util/id"
 )
 
 var (
@@ -23,17 +24,16 @@ type node struct {
 }
 
 type record struct {
-	Name     string
-	Version  string
-	Metadata map[string]string
-	Nodes    map[string]*node
+	Name    string
+	Version string
+	Nodes   map[string]*node
 }
 
 type memory struct {
 	records  map[string]services
 	watchers map[string]*watcher
 	opts     register.Options
-	sync.RWMutex
+	mu       sync.RWMutex
 }
 
 // services is a KV map with service name as the key and a map of records as the value
@@ -57,7 +57,7 @@ func (m *memory) ttlPrune() {
 	defer prune.Stop()
 
 	for range prune.C {
-		m.Lock()
+		m.mu.Lock()
 		for namespace, services := range m.records {
 			for service, versions := range services {
 				for version, record := range versions {
@@ -72,24 +72,24 @@ func (m *memory) ttlPrune() {
 				}
 			}
 		}
-		m.Unlock()
+		m.mu.Unlock()
 	}
 }
 
 func (m *memory) sendEvent(r *register.Result) {
-	m.RLock()
+	m.mu.RLock()
 	watchers := make([]*watcher, 0, len(m.watchers))
 	for _, w := range m.watchers {
 		watchers = append(watchers, w)
 	}
-	m.RUnlock()
+	m.mu.RUnlock()
 
 	for _, w := range watchers {
 		select {
 		case <-w.exit:
-			m.Lock()
+			m.mu.Lock()
 			delete(m.watchers, w.id)
-			m.Unlock()
+			m.mu.Unlock()
 		default:
 			select {
 			case w.res <- r:
@@ -113,8 +113,8 @@ func (m *memory) Init(opts ...register.Option) error {
 	}
 
 	// add services
-	m.Lock()
-	defer m.Unlock()
+	m.mu.Lock()
+	defer m.mu.Unlock()
 
 	return nil
 }
@@ -124,8 +124,8 @@ func (m *memory) Options() register.Options {
 }
 
 func (m *memory) Register(_ context.Context, s *register.Service, opts ...register.RegisterOption) error {
-	m.Lock()
-	defer m.Unlock()
+	m.mu.Lock()
+	defer m.mu.Unlock()
 
 	options := register.NewRegisterOptions(opts...)
 
@@ -160,19 +160,14 @@ func (m *memory) Register(_ context.Context, s *register.Service, opts ...regist
 			continue
 		}
 
-		metadata := make(map[string]string, len(n.Metadata))
-
-		// make copy of metadata
-		for k, v := range n.Metadata {
-			metadata[k] = v
-		}
+		md := metadata.Copy(n.Metadata)
 
 		// add the node
 		srvs[s.Name][s.Version].Nodes[n.ID] = &node{
 			Node: &register.Node{
 				ID:       n.ID,
 				Address:  n.Address,
-				Metadata: metadata,
+				Metadata: md,
 			},
 			TTL:      options.TTL,
 			LastSeen: time.Now(),
@@ -202,8 +197,8 @@ func (m *memory) Register(_ context.Context, s *register.Service, opts ...regist
 }
 
 func (m *memory) Deregister(ctx context.Context, s *register.Service, opts ...register.DeregisterOption) error {
-	m.Lock()
-	defer m.Unlock()
+	m.mu.Lock()
+	defer m.mu.Unlock()
 
 	options := register.NewDeregisterOptions(opts...)
 
@@ -269,9 +264,9 @@ func (m *memory) LookupService(ctx context.Context, name string, opts ...registe
 
 	// if it's a wildcard domain, return from all domains
 	if options.Namespace == register.WildcardNamespace {
-		m.RLock()
+		m.mu.RLock()
 		recs := m.records
-		m.RUnlock()
+		m.mu.RUnlock()
 
 		var services []*register.Service
 
@@ -291,8 +286,8 @@ func (m *memory) LookupService(ctx context.Context, name string, opts ...registe
 		return services, nil
 	}
 
-	m.RLock()
-	defer m.RUnlock()
+	m.mu.RLock()
+	defer m.mu.RUnlock()
 
 	// check the domain exists
 	services, ok := m.records[options.Namespace]
@@ -324,9 +319,9 @@ func (m *memory) ListServices(ctx context.Context, opts ...register.ListOption)
 
 	// if it's a wildcard domain, list from all domains
 	if options.Namespace == register.WildcardNamespace {
-		m.RLock()
+		m.mu.RLock()
 		recs := m.records
-		m.RUnlock()
+		m.mu.RUnlock()
 
 		var services []*register.Service
 
@@ -341,8 +336,8 @@ func (m *memory) ListServices(ctx context.Context, opts ...register.ListOption)
 		return services, nil
 	}
 
-	m.RLock()
-	defer m.RUnlock()
+	m.mu.RLock()
+	defer m.mu.RUnlock()
 
 	// ensure the domain exists
 	services, ok := m.records[options.Namespace]
@@ -376,9 +371,9 @@ func (m *memory) Watch(ctx context.Context, opts ...register.WatchOption) (regis
 		wo:   wo,
 	}
 
-	m.Lock()
+	m.mu.Lock()
 	m.watchers[w.id] = w
-	m.Unlock()
+	m.mu.Unlock()
 
 	return w, nil
 }
@@ -452,23 +447,15 @@ func serviceToRecord(s *register.Service, ttl time.Duration) *record {
 }
 
 func recordToService(r *record, namespace string) *register.Service {
-	metadata := make(map[string]string, len(r.Metadata))
-	for k, v := range r.Metadata {
-		metadata[k] = v
-	}
-
 	nodes := make([]*register.Node, len(r.Nodes))
 	i := 0
 	for _, n := range r.Nodes {
-		md := make(map[string]string, len(n.Metadata))
-		for k, v := range n.Metadata {
-			md[k] = v
-		}
+		nmd := metadata.Copy(n.Metadata)
 
 		nodes[i] = &register.Node{
 			ID:       n.ID,
 			Address:  n.Address,
-			Metadata: md,
+			Metadata: nmd,
 		}
 		i++
 	}

register/memory/memory_test.go

@@ -7,7 +7,7 @@ import (
 	"testing"
 	"time"
 
-	"go.unistack.org/micro/v3/register"
+	"go.unistack.org/micro/v4/register"
 )
 
 var testData = map[string][]*register.Service{

register/options.go

@@ -5,10 +5,10 @@ import (
 	"crypto/tls"
 	"time"
 
-	"go.unistack.org/micro/v3/codec"
-	"go.unistack.org/micro/v3/logger"
-	"go.unistack.org/micro/v3/meter"
-	"go.unistack.org/micro/v3/tracer"
+	"go.unistack.org/micro/v4/codec"
+	"go.unistack.org/micro/v4/logger"
+	"go.unistack.org/micro/v4/meter"
+	"go.unistack.org/micro/v4/tracer"
 )
 
 // Options holds options for register

register/register.go

@@ -5,7 +5,7 @@ import (
 	"context"
 	"errors"
 
-	"go.unistack.org/micro/v3/metadata"
+	"go.unistack.org/micro/v4/metadata"
 )
 
 const (
@@ -69,7 +69,8 @@ type Service struct {
 type Node struct {
 	Metadata metadata.Metadata `json:"metadata,omitempty"`
 	ID       string            `json:"id,omitempty"`
-	Address  string            `json:"address,omitempty"`
+	// Address also prefixed with scheme like grpc://xx.xx.xx.xx:1234
+	Address string `json:"address,omitempty"`
 }
 
 // Option func signature

resolver/dns/dns.go

@@ -7,7 +7,7 @@ import (
 	"sync"
 	"time"
 
-	"go.unistack.org/micro/v3/resolver"
+	"go.unistack.org/micro/v4/resolver"
 )
 
 // Resolver is a DNS network resolve

resolver/dnssrv/dnssrv.go

@@ -5,7 +5,7 @@ import (
 	"fmt"
 	"net"
 
-	"go.unistack.org/micro/v3/resolver"
+	"go.unistack.org/micro/v4/resolver"
 )
 
 // Resolver is a DNS network resolve

resolver/http/http.go

@@ -8,7 +8,7 @@ import (
 	"net/http"
 	"net/url"
 
-	"go.unistack.org/micro/v3/resolver"
+	"go.unistack.org/micro/v4/resolver"
 )
 
 // nolint: golint,revive

resolver/noop/noop.go

@@ -2,7 +2,7 @@
 package noop
 
 import (
-	"go.unistack.org/micro/v3/resolver"
+	"go.unistack.org/micro/v4/resolver"
 )
 
 // Resolver contains noop resolver