add copy metadata from grpc-go (#386)

Co-authored-by: Василий Толстов <v.tolstov@unistack.org>
Co-authored-by: Vasiliy Tolstov <v.tolstov@unistack.org>
Co-authored-by: vtolstov <vtolstov@users.noreply.github.com>
Reviewed-on: #386
Co-authored-by: Evstigneev Denis <danteevstigneev@yandex.ru>
Co-committed-by: Evstigneev Denis <danteevstigneev@yandex.ru>

.gitea/workflows/job_coverage.yml

@@ -3,16 +3,14 @@ name: coverage
 on:
   push:
     branches: [ main, v3, v4 ]
-    paths-ignore:
-      - '.github/**'
-      - '.gitea/**'
   pull_request:
     branches: [ main, v3, v4 ]
+  # Allows you to run this workflow manually from the Actions tab
+  workflow_dispatch:
 
 jobs:
 
   build:
-    if: github.server_url != 'https://github.com'
     runs-on: ubuntu-latest
     steps:
     - name: checkout code
@@ -41,8 +39,8 @@ jobs:
       name: autocommit
       with:
         commit_message: Apply Code Coverage Badge
-        skip_fetch: false
+        skip_fetch: true
-        skip_checkout: false
+        skip_checkout: true
         file_pattern: ./README.md
 
     - name: push

.gitea/workflows/job_lint.yml

@@ -3,10 +3,10 @@ name: lint
 on:
   pull_request:
     types: [opened, reopened, synchronize]
-    branches: [ master, v3, v4 ]
+    branches:
-    paths-ignore:
+    - master
-      - '.github/**'
+    - v3
-      - '.gitea/**'
+    - v4
 
 jobs:
   lint:
@@ -24,6 +24,6 @@ jobs:
     - name: setup deps
       run: go get -v ./...
     - name: run lint
-      uses: golangci/golangci-lint-action@v6
+      uses: https://github.com/golangci/golangci-lint-action@v6
       with:
         version: 'latest'

.gitea/workflows/job_test.yml

@@ -3,12 +3,15 @@ name: test
 on:
   pull_request:
     types: [opened, reopened, synchronize]
-    branches: [ master, v3, v4 ]
+    branches:
+    - master
+    - v3
+    - v4
   push:
-    branches: [ master, v3, v4 ]
+    branches:
-    paths-ignore:
+    - master
-      - '.github/**'
+    - v3
-      - '.gitea/**'
+    - v4
 
 jobs:
   test:

.gitea/workflows/job_tests.yml

@@ -3,12 +3,15 @@ name: test
 on:
   pull_request:
     types: [opened, reopened, synchronize]
-    branches: [ master, v3, v4 ]
+    branches:
+    - master
+    - v3
+    - v4
   push:
-    branches: [ master, v3, v4 ]
+    branches:
-    paths-ignore:
+    - master
-      - '.github/**'
+    - v3
-      - '.gitea/**'
+    - v4
 
 jobs:
   test:
@@ -32,19 +35,19 @@ jobs:
         go-version: 'stable'
     - name: setup go work
       env:
-        GOWORK: ${{ github.workspace }}/go.work
+        GOWORK: /workspace/${{ github.repository_owner }}/go.work
       run: |
         go work init
         go work use .
         go work use micro-tests
     - name: setup deps
       env:
-        GOWORK: ${{ github.workspace }}/go.work
+        GOWORK: /workspace/${{ github.repository_owner }}/go.work
       run: go get -v ./...
     - name: run tests
       env:
         INTEGRATION_TESTS: yes
-        GOWORK: ${{ github.workspace }}/go.work
+        GOWORK: /workspace/${{ github.repository_owner }}/go.work
       run: |
         cd micro-tests
         go test -mod readonly -v ./... || true

.golangci.yml

@@ -1,5 +1,5 @@
 run:
   concurrency: 8
-  timeout: 5m
+  deadline: 5m
   issues-exit-code: 1
   tests: true

README.md

@@ -1,5 +1,5 @@
 # Micro
-![Coverage](https://img.shields.io/badge/Coverage-33.6%25-yellow)
+![Coverage](https://img.shields.io/badge/Coverage-44.6%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)
@@ -9,20 +9,20 @@ 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 

SECURITY.md

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

broker/broker.go

@@ -6,8 +6,8 @@ import (
 	"errors"
 	"time"
 
-	"go.unistack.org/micro/v3/codec"
+	"go.unistack.org/micro/v4/codec"
-	"go.unistack.org/micro/v3/metadata"
+	"go.unistack.org/micro/v4/metadata"
 )
 
 // DefaultBroker default memory broker

broker/memory/memory.go

@@ -4,14 +4,14 @@ import (
 	"context"
 	"sync"
 
-	"go.unistack.org/micro/v3/broker"
+	"go.unistack.org/micro/v4/broker"
-	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v4/logger"
-	"go.unistack.org/micro/v3/metadata"
+	"go.unistack.org/micro/v4/metadata"
-	"go.unistack.org/micro/v3/options"
+	"go.unistack.org/micro/v4/options"
-	maddr "go.unistack.org/micro/v3/util/addr"
+	maddr "go.unistack.org/micro/v4/util/addr"
-	"go.unistack.org/micro/v3/util/id"
+	"go.unistack.org/micro/v4/util/id"
-	mnet "go.unistack.org/micro/v3/util/net"
+	mnet "go.unistack.org/micro/v4/util/net"
-	"go.unistack.org/micro/v3/util/rand"
+	"go.unistack.org/micro/v4/util/rand"
 )
 
 type memoryBroker struct {

broker/memory/memory_test.go

@@ -5,8 +5,8 @@ import (
 	"fmt"
 	"testing"
 
-	"go.unistack.org/micro/v3/broker"
+	"go.unistack.org/micro/v4/broker"
-	"go.unistack.org/micro/v3/metadata"
+	"go.unistack.org/micro/v4/metadata"
 )
 
 func TestMemoryBatchBroker(t *testing.T) {

broker/noop.go

@@ -4,7 +4,7 @@ import (
 	"context"
 	"strings"
 
-	"go.unistack.org/micro/v3/options"
+	"go.unistack.org/micro/v4/options"
 )
 
 type NoopBroker struct {

broker/options.go

@@ -5,13 +5,13 @@ import (
 	"crypto/tls"
 	"time"
 
-	"go.unistack.org/micro/v3/codec"
+	"go.unistack.org/micro/v4/codec"
-	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v4/logger"
-	"go.unistack.org/micro/v3/meter"
+	"go.unistack.org/micro/v4/meter"
-	"go.unistack.org/micro/v3/options"
+	"go.unistack.org/micro/v4/options"
-	"go.unistack.org/micro/v3/register"
+	"go.unistack.org/micro/v4/register"
-	"go.unistack.org/micro/v3/sync"
+	"go.unistack.org/micro/v4/sync"
-	"go.unistack.org/micro/v3/tracer"
+	"go.unistack.org/micro/v4/tracer"
 )
 
 // Options struct

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/v4/codec"
-	"go.unistack.org/micro/v3/metadata"
+	"go.unistack.org/micro/v4/metadata"
 )
 
 var (

client/lookup.go

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

client/noop.go

@@ -7,14 +7,14 @@ import (
 	"strconv"
 	"time"
 
-	"go.unistack.org/micro/v3/broker"
+	"go.unistack.org/micro/v4/broker"
-	"go.unistack.org/micro/v3/codec"
+	"go.unistack.org/micro/v4/codec"
-	"go.unistack.org/micro/v3/errors"
+	"go.unistack.org/micro/v4/errors"
-	"go.unistack.org/micro/v3/metadata"
+	"go.unistack.org/micro/v4/metadata"
-	"go.unistack.org/micro/v3/options"
+	"go.unistack.org/micro/v4/options"
-	"go.unistack.org/micro/v3/selector"
+	"go.unistack.org/micro/v4/selector"
-	"go.unistack.org/micro/v3/semconv"
+	"go.unistack.org/micro/v4/semconv"
-	"go.unistack.org/micro/v3/tracer"
+	"go.unistack.org/micro/v4/tracer"
 )
 
 // DefaultCodecs will be used to encode/decode data

client/options.go

@@ -6,17 +6,17 @@ import (
 	"net"
 	"time"
 
-	"go.unistack.org/micro/v3/broker"
+	"go.unistack.org/micro/v4/broker"
-	"go.unistack.org/micro/v3/codec"
+	"go.unistack.org/micro/v4/codec"
-	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v4/logger"
-	"go.unistack.org/micro/v3/metadata"
+	"go.unistack.org/micro/v4/metadata"
-	"go.unistack.org/micro/v3/meter"
+	"go.unistack.org/micro/v4/meter"
-	"go.unistack.org/micro/v3/options"
+	"go.unistack.org/micro/v4/options"
-	"go.unistack.org/micro/v3/register"
+	"go.unistack.org/micro/v4/register"
-	"go.unistack.org/micro/v3/router"
+	"go.unistack.org/micro/v4/router"
-	"go.unistack.org/micro/v3/selector"
+	"go.unistack.org/micro/v4/selector"
-	"go.unistack.org/micro/v3/selector/random"
+	"go.unistack.org/micro/v4/selector/random"
-	"go.unistack.org/micro/v3/tracer"
+	"go.unistack.org/micro/v4/tracer"
 )
 
 // Options holds client options

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

codec/options.go

@@ -3,9 +3,9 @@ package codec
 import (
 	"context"
 
-	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v4/logger"
-	"go.unistack.org/micro/v3/meter"
+	"go.unistack.org/micro/v4/meter"
-	"go.unistack.org/micro/v3/tracer"
+	"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"
+	"go.unistack.org/micro/v4/options"
-	mid "go.unistack.org/micro/v3/util/id"
+	mid "go.unistack.org/micro/v4/util/id"
-	rutil "go.unistack.org/micro/v3/util/reflect"
+	rutil "go.unistack.org/micro/v4/util/reflect"
-	mtime "go.unistack.org/micro/v3/util/time"
+	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"
+	"go.unistack.org/micro/v4/config"
-	mtime "go.unistack.org/micro/v3/util/time"
+	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/v4/codec"
-	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v4/logger"
-	"go.unistack.org/micro/v3/meter"
+	"go.unistack.org/micro/v4/meter"
-	"go.unistack.org/micro/v3/options"
+	"go.unistack.org/micro/v4/options"
-	"go.unistack.org/micro/v3/tracer"
+	"go.unistack.org/micro/v4/tracer"
 )
 
 // Options hold the config options

event.go

@@ -3,7 +3,7 @@ package micro
 import (
 	"context"
 
-	"go.unistack.org/micro/v3/client"
+	"go.unistack.org/micro/v4/client"
 )
 
 // Event is used to publish messages to a topic

flow/default.go

@@ -6,12 +6,12 @@ import (
 	"sync"
 
 	"github.com/silas/dag"
-	"go.unistack.org/micro/v3/client"
+	"go.unistack.org/micro/v4/client"
-	"go.unistack.org/micro/v3/codec"
+	"go.unistack.org/micro/v4/codec"
-	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v4/logger"
-	"go.unistack.org/micro/v3/metadata"
+	"go.unistack.org/micro/v4/metadata"
-	"go.unistack.org/micro/v3/store"
+	"go.unistack.org/micro/v4/store"
-	"go.unistack.org/micro/v3/util/id"
+	"go.unistack.org/micro/v4/util/id"
 )
 
 type microFlow struct {

flow/flow.go

@@ -7,7 +7,7 @@ import (
 	"sync"
 	"sync/atomic"
 
-	"go.unistack.org/micro/v3/metadata"
+	"go.unistack.org/micro/v4/metadata"
 )
 
 var (

flow/options.go

@@ -4,11 +4,11 @@ import (
 	"context"
 	"time"
 
-	"go.unistack.org/micro/v3/client"
+	"go.unistack.org/micro/v4/client"
-	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v4/logger"
-	"go.unistack.org/micro/v3/meter"
+	"go.unistack.org/micro/v4/meter"
-	"go.unistack.org/micro/v3/store"
+	"go.unistack.org/micro/v4/store"
-	"go.unistack.org/micro/v3/tracer"
+	"go.unistack.org/micro/v4/tracer"
 )
 
 // Option func

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

@@ -1,22 +1,21 @@
-module go.unistack.org/micro/v3
+module go.unistack.org/micro/v4
 
 go 1.22.0
 
 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/KimMachineGun/automemlimit v0.7.0
 	github.com/ash3in/uuidv8 v1.2.0
 	github.com/google/uuid v1.6.0
 	github.com/matoous/go-nanoid v1.5.1
 	github.com/patrickmn/go-cache v2.1.0+incompatible
 	github.com/silas/dag v0.0.0-20220518035006-a7e85ada93c5
-	github.com/stretchr/testify v1.10.0
 	go.uber.org/automaxprocs v1.6.0
 	go.unistack.org/micro-proto/v3 v3.4.1
 	golang.org/x/sync v0.10.0
-	google.golang.org/grpc v1.69.2
+	google.golang.org/grpc v1.69.4
-	google.golang.org/protobuf v1.36.1
+	google.golang.org/protobuf v1.36.3
 	gopkg.in/yaml.v3 v3.0.1
 )
 
@@ -34,10 +33,11 @@ require (
 	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
+	github.com/stretchr/testify v1.10.0 // 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/net v0.34.0 // indirect
-	golang.org/x/sys v0.28.0 // 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
 )

hooks/metadata/metadata.go

@@ -1,76 +0,0 @@
-package metadata
-
-import (
-	"context"
-
-	"go.unistack.org/micro/v3/client"
-	"go.unistack.org/micro/v3/metadata"
-	"go.unistack.org/micro/v3/server"
-)
-
-var DefaultMetadataKeys = []string{"x-request-id"}
-
-type hook struct {
-	keys []string
-}
-
-func NewHook(keys ...string) *hook {
-	return &hook{keys: keys}
-}
-
-func metadataCopy(ctx context.Context, keys []string) context.Context {
-	if keys == nil {
-		return ctx
-	}
-	if imd, iok := metadata.FromIncomingContext(ctx); iok && imd != nil {
-		omd, ook := metadata.FromOutgoingContext(ctx)
-		if !ook || omd == nil {
-			omd = metadata.New(len(keys))
-		}
-		for _, k := range keys {
-			if v, ok := imd.Get(k); ok && v != "" {
-				omd.Set(k, v)
-			}
-		}
-		if !ook {
-			ctx = metadata.NewOutgoingContext(ctx, omd)
-		}
-	}
-	return ctx
-}
-
-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 *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)
-	}
-}

hooks/recovery/recovery.go

@@ -1,94 +0,0 @@
-package recovery
-
-import (
-	"context"
-	"fmt"
-
-	"go.unistack.org/micro/v3/errors"
-	"go.unistack.org/micro/v3/server"
-)
-
-func NewOptions(opts ...Option) Options {
-	options := Options{
-		ServerHandlerFn:    DefaultServerHandlerFn,
-		ServerSubscriberFn: DefaultServerSubscriberFn,
-	}
-	for _, o := range opts {
-		o(&options)
-	}
-	return options
-}
-
-type Options struct {
-	ServerHandlerFn    func(context.Context, server.Request, interface{}, error) error
-	ServerSubscriberFn func(context.Context, server.Message, error) error
-}
-
-type Option func(*Options)
-
-func ServerHandlerFunc(fn func(context.Context, server.Request, interface{}, error) error) Option {
-	return func(o *Options) {
-		o.ServerHandlerFn = fn
-	}
-}
-
-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)
-	}
-	DefaultServerSubscriberFn = func(ctx context.Context, req server.Message, err error) error {
-		return errors.BadRequest("", "%v", err)
-	}
-)
-
-var Hook = NewHook()
-
-type hook struct {
-	opts Options
-}
-
-func NewHook(opts ...Option) *hook {
-	return &hook{opts: NewOptions(opts...)}
-}
-
-func (w *hook) ServerHandler(next server.FuncHandler) server.FuncHandler {
-	return func(ctx context.Context, req server.Request, rsp interface{}) (err error) {
-		defer func() {
-			r := recover()
-			switch verr := r.(type) {
-			case nil:
-				return
-			case error:
-				err = w.opts.ServerHandlerFn(ctx, req, rsp, verr)
-			default:
-				err = w.opts.ServerHandlerFn(ctx, req, rsp, fmt.Errorf("%v", r))
-			}
-		}()
-		err = next(ctx, req, rsp)
-		return err
-	}
-}
-
-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

@@ -1,139 +0,0 @@
-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"
-)
-
-type XRequestIDKey struct{}
-
-// DefaultMetadataKey contains metadata key
-var DefaultMetadataKey = textproto.CanonicalMIMEHeaderKey("x-request-id")
-
-// DefaultMetadataFunc wil be used if user not provide own func to fill metadata
-var DefaultMetadataFunc = func(ctx context.Context) (context.Context, error) {
-	var xid string
-
-	cid, cok := ctx.Value(XRequestIDKey{}).(string)
-	if cok && cid != "" {
-		xid = cid
-	}
-
-	imd, iok := metadata.FromIncomingContext(ctx)
-	if !iok || imd == nil {
-		imd = metadata.New(1)
-		ctx = metadata.NewIncomingContext(ctx, imd)
-	}
-
-	omd, ook := metadata.FromOutgoingContext(ctx)
-	if !ook || omd == nil {
-		omd = metadata.New(1)
-		ctx = metadata.NewOutgoingContext(ctx, omd)
-	}
-
-	if xid == "" {
-		var id string
-		if id, iok = imd.Get(DefaultMetadataKey); iok && id != "" {
-			xid = id
-		}
-		if id, ook = omd.Get(DefaultMetadataKey); ook && id != "" {
-			xid = id
-		}
-	}
-
-	if xid == "" {
-		var err error
-		xid, err = id.New()
-		if err != nil {
-			return ctx, err
-		}
-	}
-
-	if !cok {
-		ctx = context.WithValue(ctx, XRequestIDKey{}, xid)
-	}
-
-	if !iok {
-		imd.Set(DefaultMetadataKey, xid)
-	}
-
-	if !ook {
-		omd.Set(DefaultMetadataKey, xid)
-	}
-
-	return ctx, nil
-}
-
-type hook struct{}
-
-func NewHook() *hook {
-	return &hook{}
-}
-
-func (w *hook) 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
-		if ctx, err = DefaultMetadataFunc(ctx); err != nil {
-			return err
-		}
-		return next(ctx, req, rsp)
-	}
-}
-
-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
-		if ctx, err = DefaultMetadataFunc(ctx); err != nil {
-			return err
-		}
-		return next(ctx, req, rsp, opts...)
-	}
-}
-
-func (w *hook) ClientStream(next client.FuncStream) client.FuncStream {
-	return func(ctx context.Context, req client.Request, opts ...client.CallOption) (client.Stream, error) {
-		var err error
-		if ctx, err = DefaultMetadataFunc(ctx); err != nil {
-			return nil, err
-		}
-		return next(ctx, req, opts...)
-	}
-}

hooks/requestid/requestid_test.go

@@ -1,33 +0,0 @@
-package requestid
-
-import (
-	"context"
-	"testing"
-
-	"go.unistack.org/micro/v3/metadata"
-)
-
-func TestDefaultMetadataFunc(t *testing.T) {
-	ctx := context.TODO()
-
-	nctx, err := DefaultMetadataFunc(ctx)
-	if err != nil {
-		t.Fatalf("%v", err)
-	}
-
-	imd, ok := metadata.FromIncomingContext(nctx)
-	if !ok {
-		t.Fatalf("md missing in incoming context")
-	}
-	omd, ok := metadata.FromOutgoingContext(nctx)
-	if !ok {
-		t.Fatalf("md missing in outgoing context")
-	}
-
-	_, iok := imd.Get(DefaultMetadataKey)
-	_, ook := omd.Get(DefaultMetadataKey)
-
-	if !iok || !ook {
-		t.Fatalf("missing metadata key value")
-	}
-}

hooks/sql/common.go

@@ -1,51 +0,0 @@
-package sql
-
-import (
-	"database/sql/driver"
-	"errors"
-	"fmt"
-	"runtime"
-)
-
-//go:generate sh -c "go run gen.go > wrap_gen.go"
-
-// namedValueToValue converts driver arguments of NamedValue format to Value format. Implemented in the same way as in
-// database/sql ctxutil.go.
-func namedValueToValue(named []driver.NamedValue) ([]driver.Value, error) {
-	dargs := make([]driver.Value, len(named))
-	for n, param := range named {
-		if len(param.Name) > 0 {
-			return nil, errors.New("sql: driver does not support the use of Named Parameters")
-		}
-		dargs[n] = param.Value
-	}
-	return dargs, nil
-}
-
-// namedValueToLabels convert driver arguments to interface{} slice
-func namedValueToLabels(named []driver.NamedValue) []interface{} {
-	largs := make([]interface{}, 0, len(named)*2)
-	var name string
-	for _, param := range named {
-		if param.Name != "" {
-			name = param.Name
-		} else {
-			name = fmt.Sprintf("$%d", param.Ordinal)
-		}
-		largs = append(largs, fmt.Sprintf("%s=%v", name, param.Value))
-	}
-	return largs
-}
-
-// getCallerName get the name of the function A where A() -> B() -> GetFunctionCallerName()
-func getCallerName() string {
-	pc, _, _, ok := runtime.Caller(3)
-	details := runtime.FuncForPC(pc)
-	var callerName string
-	if ok && details != nil {
-		callerName = details.Name()
-	} else {
-		callerName = labelUnknown
-	}
-	return callerName
-}

hooks/sql/conn.go

@@ -1,467 +0,0 @@
-package sql
-
-import (
-	"context"
-	"database/sql/driver"
-	"fmt"
-	"time"
-
-	"go.unistack.org/micro/v3/hooks/requestid"
-	"go.unistack.org/micro/v3/tracer"
-)
-
-var (
-	_ driver.Conn               = (*wrapperConn)(nil)
-	_ driver.ConnBeginTx        = (*wrapperConn)(nil)
-	_ driver.ConnPrepareContext = (*wrapperConn)(nil)
-	_ driver.Pinger             = (*wrapperConn)(nil)
-	_ driver.Validator          = (*wrapperConn)(nil)
-	_ driver.Queryer            = (*wrapperConn)(nil) // nolint:staticcheck
-	_ driver.QueryerContext     = (*wrapperConn)(nil)
-	_ driver.Execer             = (*wrapperConn)(nil) // nolint:staticcheck
-	_ driver.ExecerContext      = (*wrapperConn)(nil)
-	//	_ driver.Connector
-	//	_ driver.Driver
-	//	_ driver.DriverContext
-)
-
-// wrapperConn defines a wrapper for driver.Conn
-type wrapperConn struct {
-	d     *wrapperDriver
-	dname string
-	conn  driver.Conn
-	opts  Options
-	ctx   context.Context
-	//span  tracer.Span
-}
-
-// Close implements driver.Conn Close
-func (w *wrapperConn) Close() error {
-	var ctx context.Context
-	if w.ctx != nil {
-		ctx = w.ctx
-	} else {
-		ctx = context.Background()
-	}
-	_ = ctx
-	labels := []string{labelMethod, "Close"}
-	ts := time.Now()
-	err := w.conn.Close()
-	td := time.Since(ts)
-	te := td.Seconds()
-	if err != nil {
-		w.opts.Meter.Counter(meterRequestTotal, append(labels, labelStatus, labelFailure)...).Inc()
-	} else {
-		w.opts.Meter.Counter(meterRequestTotal, append(labels, labelStatus, labelSuccess)...).Inc()
-	}
-	w.opts.Meter.Summary(meterRequestLatencyMicroseconds, labels...).Update(te)
-	w.opts.Meter.Histogram(meterRequestDurationSeconds, labels...).Update(te)
-	/*
-		if w.opts.LoggerEnabled && w.opts.Logger.V(w.opts.LoggerLevel) {
-			w.opts.Logger.Log(ctx, w.opts.LoggerLevel, w.opts.LoggerObserver(ctx, "Close", getCallerName(), td, err)...)
-		}
-	*/
-	return err
-}
-
-// Begin implements driver.Conn Begin
-func (w *wrapperConn) Begin() (driver.Tx, error) {
-	var ctx context.Context
-	if w.ctx != nil {
-		ctx = w.ctx
-	} else {
-		ctx = context.Background()
-	}
-
-	labels := []string{labelMethod, "Begin"}
-	ts := time.Now()
-	tx, err := w.conn.Begin() // nolint:staticcheck
-	td := time.Since(ts)
-	te := td.Seconds()
-	if err != nil {
-		w.opts.Meter.Counter(meterRequestTotal, append(labels, labelStatus, labelFailure)...).Inc()
-		w.opts.Meter.Summary(meterRequestLatencyMicroseconds, labels...).Update(te)
-		w.opts.Meter.Histogram(meterRequestDurationSeconds, labels...).Update(te)
-		/*
-			if w.opts.LoggerEnabled && w.opts.Logger.V(w.opts.LoggerLevel) {
-				w.opts.Logger.Log(ctx, w.opts.LoggerLevel, w.opts.LoggerObserver(ctx, "Begin", getCallerName(), td, err)...)
-			}
-		*/
-		return nil, err
-	}
-	w.opts.Meter.Counter(meterRequestTotal, append(labels, labelStatus, labelSuccess)...).Inc()
-	w.opts.Meter.Summary(meterRequestLatencyMicroseconds, labels...).Update(te)
-	w.opts.Meter.Histogram(meterRequestDurationSeconds, labels...).Update(te)
-	/*
-		if w.opts.LoggerEnabled && w.opts.Logger.V(w.opts.LoggerLevel) {
-			w.opts.Logger.Log(ctx, w.opts.LoggerLevel, w.opts.LoggerObserver(ctx, "Begin", getCallerName(), td, err)...)
-		}
-	*/
-	return &wrapperTx{tx: tx, opts: w.opts, ctx: ctx}, nil
-}
-
-// BeginTx implements driver.ConnBeginTx BeginTx
-func (w *wrapperConn) BeginTx(ctx context.Context, opts driver.TxOptions) (driver.Tx, error) {
-	name := getQueryName(ctx)
-	nctx, span := w.opts.Tracer.Start(ctx, "sdk.database", tracer.WithSpanKind(tracer.SpanKindClient))
-	span.AddLabels("db.method", "BeginTx")
-	span.AddLabels("db.statement", name)
-	if id, ok := ctx.Value(requestid.XRequestIDKey{}).(string); ok {
-		span.AddLabels("x-request-id", id)
-	}
-	labels := []string{labelMethod, "BeginTx", labelQuery, name}
-
-	connBeginTx, ok := w.conn.(driver.ConnBeginTx)
-	if !ok {
-		return w.Begin()
-	}
-
-	ts := time.Now()
-	tx, err := connBeginTx.BeginTx(nctx, opts)
-	td := time.Since(ts)
-	te := td.Seconds()
-	if err != nil {
-		w.opts.Meter.Counter(meterRequestTotal, append(labels, labelStatus, labelFailure)...).Inc()
-		w.opts.Meter.Summary(meterRequestLatencyMicroseconds, labels...).Update(te)
-		w.opts.Meter.Histogram(meterRequestDurationSeconds, labels...).Update(te)
-		span.SetStatus(tracer.SpanStatusError, err.Error())
-		/*
-			if w.opts.LoggerEnabled && w.opts.Logger.V(w.opts.LoggerLevel) {
-				w.opts.Logger.Log(ctx, w.opts.LoggerLevel, w.opts.LoggerObserver(ctx, "BeginTx", getCallerName(), td, err)...)
-			}
-		*/
-		return nil, err
-	}
-	w.opts.Meter.Counter(meterRequestTotal, append(labels, labelStatus, labelSuccess)...).Inc()
-	/*
-		if w.opts.LoggerEnabled && w.opts.Logger.V(w.opts.LoggerLevel) {
-			w.opts.Logger.Log(ctx, w.opts.LoggerLevel, w.opts.LoggerObserver(ctx, "BeginTx", getCallerName(), td, err)...)
-		}
-	*/
-	return &wrapperTx{tx: tx, opts: w.opts, ctx: ctx, span: span}, nil
-}
-
-// Prepare implements driver.Conn Prepare
-func (w *wrapperConn) Prepare(query string) (driver.Stmt, error) {
-	var ctx context.Context
-	if w.ctx != nil {
-		ctx = w.ctx
-	} else {
-		ctx = context.Background()
-	}
-	_ = ctx
-	labels := []string{labelMethod, "Prepare", labelQuery, getCallerName()}
-	ts := time.Now()
-	stmt, err := w.conn.Prepare(query)
-	td := time.Since(ts)
-	te := td.Seconds()
-	if err != nil {
-		w.opts.Meter.Counter(meterRequestTotal, append(labels, labelStatus, labelFailure)...).Inc()
-		w.opts.Meter.Summary(meterRequestLatencyMicroseconds, labels...).Update(te)
-		w.opts.Meter.Histogram(meterRequestDurationSeconds, labels...).Update(te)
-		/*
-			if w.opts.LoggerEnabled && w.opts.Logger.V(w.opts.LoggerLevel) {
-				w.opts.Logger.Log(ctx, w.opts.LoggerLevel, w.opts.LoggerObserver(ctx, "Prepare", getCallerName(), td, err)...)
-			}
-		*/
-		return nil, err
-	}
-	w.opts.Meter.Counter(meterRequestTotal, append(labels, labelStatus, labelSuccess)...).Inc()
-	w.opts.Meter.Summary(meterRequestLatencyMicroseconds, labels...).Update(te)
-	w.opts.Meter.Histogram(meterRequestDurationSeconds, labels...).Update(te)
-	/*
-		if w.opts.LoggerEnabled && w.opts.Logger.V(w.opts.LoggerLevel) {
-			w.opts.Logger.Log(ctx, w.opts.LoggerLevel, w.opts.LoggerObserver(ctx, "Prepare", getCallerName(), td, err)...)
-		}
-	*/
-	return wrapStmt(stmt, query, w.opts), nil
-}
-
-// PrepareContext implements driver.ConnPrepareContext PrepareContext
-func (w *wrapperConn) PrepareContext(ctx context.Context, query string) (driver.Stmt, error) {
-	var nctx context.Context
-	var span tracer.Span
-
-	name := getQueryName(ctx)
-	if w.ctx != nil {
-		nctx, span = w.opts.Tracer.Start(w.ctx, "sdk.database", tracer.WithSpanKind(tracer.SpanKindClient))
-	} else {
-		nctx, span = w.opts.Tracer.Start(ctx, "sdk.database", tracer.WithSpanKind(tracer.SpanKindClient))
-	}
-	span.AddLabels("db.method", "PrepareContext")
-	span.AddLabels("db.statement", name)
-	if id, ok := ctx.Value(requestid.XRequestIDKey{}).(string); ok {
-		span.AddLabels("x-request-id", id)
-	}
-	labels := []string{labelMethod, "PrepareContext", labelQuery, name}
-	conn, ok := w.conn.(driver.ConnPrepareContext)
-	if !ok {
-		return w.Prepare(query)
-	}
-
-	ts := time.Now()
-	stmt, err := conn.PrepareContext(nctx, query)
-	td := time.Since(ts)
-	te := td.Seconds()
-	if err != nil {
-		w.opts.Meter.Counter(meterRequestTotal, append(labels, labelStatus, labelFailure)...).Inc()
-		w.opts.Meter.Summary(meterRequestLatencyMicroseconds, labels...).Update(te)
-		w.opts.Meter.Histogram(meterRequestDurationSeconds, labels...).Update(te)
-		span.SetStatus(tracer.SpanStatusError, err.Error())
-		/*
-			if w.opts.LoggerEnabled && w.opts.Logger.V(w.opts.LoggerLevel) {
-				w.opts.Logger.Log(ctx, w.opts.LoggerLevel, w.opts.LoggerObserver(ctx, "PrepareContext", getCallerName(), td, err)...)
-			}
-		*/
-		return nil, err
-	}
-	w.opts.Meter.Counter(meterRequestTotal, append(labels, labelStatus, labelSuccess)...).Inc()
-	w.opts.Meter.Summary(meterRequestLatencyMicroseconds, labels...).Update(te)
-	w.opts.Meter.Histogram(meterRequestDurationSeconds, labels...).Update(te)
-	/*
-		if w.opts.LoggerEnabled && w.opts.Logger.V(w.opts.LoggerLevel) {
-			w.opts.Logger.Log(ctx, w.opts.LoggerLevel, w.opts.LoggerObserver(ctx, "PrepareContext", getCallerName(), td, err)...)
-		}
-	*/
-	return wrapStmt(stmt, query, w.opts), nil
-}
-
-// Exec implements driver.Execer Exec
-func (w *wrapperConn) Exec(query string, args []driver.Value) (driver.Result, error) {
-	var ctx context.Context
-	if w.ctx != nil {
-		ctx = w.ctx
-	} else {
-		ctx = context.Background()
-	}
-	_ = ctx
-	labels := []string{labelMethod, "Exec", labelQuery, getCallerName()}
-
-	// nolint:staticcheck
-	conn, ok := w.conn.(driver.Execer)
-	if !ok {
-		return nil, driver.ErrSkip
-	}
-
-	ts := time.Now()
-	res, err := conn.Exec(query, args)
-	td := time.Since(ts)
-	te := td.Seconds()
-	if err != nil {
-		w.opts.Meter.Counter(meterRequestTotal, append(labels, labelStatus, labelFailure)...).Inc()
-	} else {
-		w.opts.Meter.Counter(meterRequestTotal, append(labels, labelStatus, labelSuccess)...).Inc()
-	}
-	w.opts.Meter.Summary(meterRequestLatencyMicroseconds, labels...).Update(te)
-	w.opts.Meter.Histogram(meterRequestDurationSeconds, labels...).Update(te)
-	/*
-		if w.opts.LoggerEnabled && w.opts.Logger.V(w.opts.LoggerLevel) {
-			w.opts.Logger.Log(ctx, w.opts.LoggerLevel, w.opts.LoggerObserver(ctx, "Exec", getCallerName(), td, err)...)
-		}
-	*/
-	return res, err
-}
-
-// Exec implements driver.StmtExecContext ExecContext
-func (w *wrapperConn) ExecContext(ctx context.Context, query string, args []driver.NamedValue) (driver.Result, error) {
-	var nctx context.Context
-	var span tracer.Span
-
-	name := getQueryName(ctx)
-	if w.ctx != nil {
-		nctx, span = w.opts.Tracer.Start(w.ctx, "sdk.database", tracer.WithSpanKind(tracer.SpanKindClient))
-	} else {
-		nctx, span = w.opts.Tracer.Start(ctx, "sdk.database", tracer.WithSpanKind(tracer.SpanKindClient))
-	}
-	span.AddLabels("db.method", "ExecContext")
-	span.AddLabels("db.statement", name)
-	if id, ok := ctx.Value(requestid.XRequestIDKey{}).(string); ok {
-		span.AddLabels("x-request-id", id)
-	}
-	defer span.Finish()
-	if len(args) > 0 {
-		span.AddLabels("db.args", fmt.Sprintf("%v", namedValueToLabels(args)))
-	}
-	labels := []string{labelMethod, "ExecContext", labelQuery, name}
-
-	conn, ok := w.conn.(driver.ExecerContext)
-	if !ok {
-		// nolint:staticcheck
-		return nil, driver.ErrSkip
-	}
-
-	ts := time.Now()
-	res, err := conn.ExecContext(nctx, query, args)
-	td := time.Since(ts)
-	te := td.Seconds()
-	if err != nil {
-		w.opts.Meter.Counter(meterRequestTotal, append(labels, labelStatus, labelFailure)...).Inc()
-		span.SetStatus(tracer.SpanStatusError, err.Error())
-	} else {
-		w.opts.Meter.Counter(meterRequestTotal, append(labels, labelStatus, labelSuccess)...).Inc()
-	}
-	w.opts.Meter.Counter(meterRequestTotal, append(labels, labelStatus, labelSuccess)...).Inc()
-	w.opts.Meter.Summary(meterRequestLatencyMicroseconds, labels...).Update(te)
-	w.opts.Meter.Histogram(meterRequestDurationSeconds, labels...).Update(te)
-	/*
-		if w.opts.LoggerEnabled && w.opts.Logger.V(w.opts.LoggerLevel) {
-			w.opts.Logger.Log(ctx, w.opts.LoggerLevel, w.opts.LoggerObserver(ctx, "ExecContext", getCallerName(), td, err)...)
-		}
-	*/
-	return res, err
-}
-
-// Ping implements driver.Pinger Ping
-func (w *wrapperConn) Ping(ctx context.Context) error {
-	conn, ok := w.conn.(driver.Pinger)
-
-	if !ok {
-		// fallback path to check db alive
-		pc, err := w.d.Open(w.dname)
-		if err != nil {
-			return err
-		}
-		return pc.Close()
-	}
-
-	var nctx context.Context //nolint: gosimple
-	nctx = ctx
-	/*
-		var span tracer.Span
-		if w.ctx != nil {
-			nctx, span = w.opts.Tracer.Start(w.ctx, "sdk.database", tracer.WithSpanKind(tracer.SpanKindClient))
-		} else {
-			nctx, span = w.opts.Tracer.Start(ctx, "sdk.database", tracer.WithSpanKind(tracer.SpanKindClient))
-		}
-		span.AddLabels("db.method", "Ping")
-		defer span.Finish()
-	*/
-	labels := []string{labelMethod, "Ping"}
-	ts := time.Now()
-	err := conn.Ping(nctx)
-	td := time.Since(ts)
-	te := td.Seconds()
-	if err != nil {
-		w.opts.Meter.Counter(meterRequestTotal, append(labels, labelStatus, labelFailure)...).Inc()
-		// span.SetStatus(tracer.SpanStatusError, err.Error())
-		/*
-			if w.opts.LoggerEnabled && w.opts.Logger.V(w.opts.LoggerLevel) {
-				w.opts.Logger.Log(ctx, w.opts.LoggerLevel, w.opts.LoggerObserver(ctx, "Ping", getCallerName(), td, err)...)
-			}
-		*/
-		return err
-	} else {
-		w.opts.Meter.Counter(meterRequestTotal, append(labels, labelStatus, labelSuccess)...).Inc()
-	}
-	w.opts.Meter.Summary(meterRequestLatencyMicroseconds, labels...).Update(te)
-	w.opts.Meter.Histogram(meterRequestDurationSeconds, labels...).Update(te)
-
-	return nil
-}
-
-// Query implements driver.Queryer Query
-func (w *wrapperConn) Query(query string, args []driver.Value) (driver.Rows, error) {
-	var ctx context.Context
-	if w.ctx != nil {
-		ctx = w.ctx
-	} else {
-		ctx = context.Background()
-	}
-	_ = ctx
-	// nolint:staticcheck
-	conn, ok := w.conn.(driver.Queryer)
-	if !ok {
-		return nil, driver.ErrSkip
-	}
-
-	labels := []string{labelMethod, "Query", labelQuery, getCallerName()}
-	ts := time.Now()
-	rows, err := conn.Query(query, args)
-	td := time.Since(ts)
-	te := td.Seconds()
-	if err != nil {
-		w.opts.Meter.Counter(meterRequestTotal, append(labels, labelStatus, labelFailure)...).Inc()
-	} else {
-		w.opts.Meter.Counter(meterRequestTotal, append(labels, labelStatus, labelSuccess)...).Inc()
-	}
-	w.opts.Meter.Summary(meterRequestLatencyMicroseconds, labels...).Update(te)
-	w.opts.Meter.Histogram(meterRequestDurationSeconds, labels...).Update(te)
-	/*
-		if w.opts.LoggerEnabled && w.opts.Logger.V(w.opts.LoggerLevel) {
-			w.opts.Logger.Log(ctx, w.opts.LoggerLevel, w.opts.LoggerObserver(ctx, "Query", getCallerName(), td, err)...)
-		}
-	*/
-	return rows, err
-}
-
-// QueryContext implements Driver.QueryerContext QueryContext
-func (w *wrapperConn) QueryContext(ctx context.Context, query string, args []driver.NamedValue) (driver.Rows, error) {
-	var nctx context.Context
-	var span tracer.Span
-
-	name := getQueryName(ctx)
-	if w.ctx != nil {
-		nctx, span = w.opts.Tracer.Start(w.ctx, "sdk.database", tracer.WithSpanKind(tracer.SpanKindClient))
-	} else {
-		nctx, span = w.opts.Tracer.Start(ctx, "sdk.database", tracer.WithSpanKind(tracer.SpanKindClient))
-	}
-	span.AddLabels("db.method", "QueryContext")
-	span.AddLabels("db.statement", name)
-	if id, ok := ctx.Value(requestid.XRequestIDKey{}).(string); ok {
-		span.AddLabels("x-request-id", id)
-	}
-	defer span.Finish()
-	if len(args) > 0 {
-		span.AddLabels("db.args", fmt.Sprintf("%v", namedValueToLabels(args)))
-	}
-	labels := []string{labelMethod, "QueryContext", labelQuery, name}
-	conn, ok := w.conn.(driver.QueryerContext)
-	if !ok {
-		return nil, driver.ErrSkip
-	}
-
-	ts := time.Now()
-	rows, err := conn.QueryContext(nctx, query, args)
-	td := time.Since(ts)
-	te := td.Seconds()
-	if err != nil {
-		w.opts.Meter.Counter(meterRequestTotal, append(labels, labelStatus, labelFailure)...).Inc()
-		span.SetStatus(tracer.SpanStatusError, err.Error())
-	} else {
-		w.opts.Meter.Counter(meterRequestTotal, append(labels, labelStatus, labelSuccess)...).Inc()
-	}
-	w.opts.Meter.Summary(meterRequestLatencyMicroseconds, labels...).Update(te)
-	w.opts.Meter.Histogram(meterRequestDurationSeconds, labels...).Update(te)
-	/*
-		if w.opts.LoggerEnabled && w.opts.Logger.V(w.opts.LoggerLevel) {
-			w.opts.Logger.Log(ctx, w.opts.LoggerLevel, w.opts.LoggerObserver(ctx, "QueryContext", getCallerName(), td, err)...)
-		}
-	*/
-	return rows, err
-}
-
-// CheckNamedValue implements driver.NamedValueChecker
-func (w *wrapperConn) CheckNamedValue(v *driver.NamedValue) error {
-	s, ok := w.conn.(driver.NamedValueChecker)
-	if !ok {
-		return driver.ErrSkip
-	}
-	return s.CheckNamedValue(v)
-}
-
-// IsValid implements driver.Validator
-func (w *wrapperConn) IsValid() bool {
-	v, ok := w.conn.(driver.Validator)
-	if !ok {
-		return w.conn != nil
-	}
-	return v.IsValid()
-}
-
-func (w *wrapperConn) ResetSession(ctx context.Context) error {
-	s, ok := w.conn.(driver.SessionResetter)
-	if !ok {
-		return driver.ErrSkip
-	}
-	return s.ResetSession(ctx)
-}

hooks/sql/driver.go

@@ -1,94 +0,0 @@
-package sql
-
-import (
-	"context"
-	"database/sql/driver"
-	"time"
-)
-
-var (
-// _ driver.DriverContext = (*wrapperDriver)(nil)
-// _ driver.Connector     = (*wrapperDriver)(nil)
-)
-
-/*
-type conn interface {
-	driver.Pinger
-	driver.Execer
-	driver.ExecerContext
-	driver.Queryer
-	driver.QueryerContext
-	driver.Conn
-	driver.ConnPrepareContext
-	driver.ConnBeginTx
-}
-*/
-
-// wrapperDriver defines a wrapper for driver.Driver
-type wrapperDriver struct {
-	driver driver.Driver
-	opts   Options
-	ctx    context.Context
-}
-
-// NewWrapper creates and returns a new SQL driver with passed capabilities
-func NewWrapper(d driver.Driver, opts ...Option) driver.Driver {
-	return &wrapperDriver{driver: d, opts: NewOptions(opts...), ctx: context.Background()}
-}
-
-type wrappedConnector struct {
-	connector driver.Connector
-//	name      string
-	opts      Options
-	ctx       context.Context
-}
-
-func NewWrapperConnector(c driver.Connector, opts ...Option) driver.Connector {
-	return &wrappedConnector{connector: c, opts: NewOptions(opts...), ctx: context.Background()}
-}
-
-// Connect implements driver.Driver Connect
-func (w *wrappedConnector) Connect(ctx context.Context) (driver.Conn, error) {
-	return w.connector.Connect(ctx)
-}
-
-// Driver implements driver.Driver Driver
-func (w *wrappedConnector) Driver() driver.Driver {
-	return w.connector.Driver()
-}
-
-/*
-// Connect implements driver.Driver OpenConnector
-func (w *wrapperDriver) OpenConnector(name string) (driver.Conn, error) {
-	return &wrapperConnector{driver: w.driver, name: name, opts: w.opts}, nil
-}
-*/
-
-// Open implements driver.Driver Open
-func (w *wrapperDriver) Open(name string) (driver.Conn, error) {
-	// ctx, cancel := context.WithTimeout(context.Background(), 60*time.Second) // Ensure eventual timeout
-	// defer cancel()
-
-	/*
-		connector, err := w.OpenConnector(name)
-		if err != nil {
-			return nil, err
-		}
-		return connector.Connect(ctx)
-	*/
-
-	ts := time.Now()
-	c, err := w.driver.Open(name)
-	td := time.Since(ts)
-	/*
-		if w.opts.LoggerEnabled {
-			w.opts.Logger.Log(w.ctx, w.opts.LoggerLevel, w.opts.LoggerObserver(w.ctx, "Open", getCallerName(), td, err)...)
-		}
-	*/
-	_ = td
-	if err != nil {
-		return nil, err
-	}
-
-	return wrapConn(c, w.opts), nil
-}

hooks/sql/gen.go

@@ -1,165 +0,0 @@
-//go:build ignore
-
-package main
-
-import (
-	"bytes"
-	"crypto/md5"
-	"fmt"
-	"io"
-	"sort"
-	"strings"
-)
-
-var connIfaces = []string{
-	"driver.ConnBeginTx",
-	"driver.ConnPrepareContext",
-	"driver.Execer",
-	"driver.ExecerContext",
-	"driver.NamedValueChecker",
-	"driver.Pinger",
-	"driver.Queryer",
-	"driver.QueryerContext",
-	"driver.SessionResetter",
-	"driver.Validator",
-}
-
-var stmtIfaces = []string{
-	"driver.StmtExecContext",
-	"driver.StmtQueryContext",
-	"driver.ColumnConverter",
-	"driver.NamedValueChecker",
-}
-
-func getHash(s []string) string {
-	h := md5.New()
-	io.WriteString(h, strings.Join(s, "|"))
-	return fmt.Sprintf("%x", h.Sum(nil))
-}
-
-func main() {
-	comboConn := all(connIfaces)
-
-	sort.Slice(comboConn, func(i, j int) bool {
-		return len(comboConn[i]) < len(comboConn[j])
-	})
-
-	comboStmt := all(stmtIfaces)
-
-	sort.Slice(comboStmt, func(i, j int) bool {
-		return len(comboStmt[i]) < len(comboStmt[j])
-	})
-
-	b := bytes.NewBuffer(nil)
-	b.WriteString("// Code generated. DO NOT EDIT.\n\n")
-	b.WriteString("package sql\n\n")
-	b.WriteString(`import "database/sql/driver"`)
-	b.WriteString("\n\n")
-
-	b.WriteString("func wrapConn(dc driver.Conn, opts Options) driver.Conn {\n")
-	b.WriteString("\tc := &wrapperConn{conn: dc, opts: opts}\n")
-
-	for idx := len(comboConn) - 1; idx >= 0; idx-- {
-		ifaces := comboConn[idx]
-		n := len(ifaces)
-		if n == 0 {
-			continue
-		}
-		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}{")
-		for idx := range ifaces {
-			if idx > 0 {
-				b.WriteString(", ")
-				b.WriteString("c")
-			} else if idx == 0 {
-				b.WriteString("c")
-			} else {
-				b.WriteString("c")
-			}
-		}
-		b.WriteString(", c}\n")
-		b.WriteString("\t}\n\n")
-	}
-	b.WriteString("\treturn c\n")
-	b.WriteString("}\n\n")
-
-	for idx := len(comboConn) - 1; idx >= 0; idx-- {
-		ifaces := comboConn[idx]
-		n := len(ifaces)
-		if n == 0 {
-			continue
-		}
-		h := getHash(ifaces)
-		b.WriteString(fmt.Sprintf("// %s\n", strings.Join(ifaces, "|")))
-		b.WriteString(fmt.Sprintf("type wrapConn%04d_%s interface {\n", n, h))
-		for _, iface := range ifaces {
-			b.WriteString(fmt.Sprintf("\t%s\n", iface))
-		}
-		b.WriteString("}\n\n")
-	}
-
-	b.WriteString("func wrapStmt(stmt driver.Stmt, query string, opts Options) driver.Stmt {\n")
-	b.WriteString("\tc := &wrapperStmt{stmt: stmt, query: query, opts: opts}\n")
-
-	for idx := len(comboStmt) - 1; idx >= 0; idx-- {
-		ifaces := comboStmt[idx]
-		n := len(ifaces)
-		if n == 0 {
-			continue
-		}
-		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}{")
-		for idx := range ifaces {
-			if idx > 0 {
-				b.WriteString(", ")
-				b.WriteString("c")
-			} else if idx == 0 {
-				b.WriteString("c")
-			} else {
-				b.WriteString("c")
-			}
-		}
-		b.WriteString(", c}\n")
-		b.WriteString("\t}\n\n")
-	}
-	b.WriteString("\treturn c\n")
-	b.WriteString("}\n")
-
-	for idx := len(comboStmt) - 1; idx >= 0; idx-- {
-		ifaces := comboStmt[idx]
-		n := len(ifaces)
-		if n == 0 {
-			continue
-		}
-		h := getHash(ifaces)
-		b.WriteString(fmt.Sprintf("\n// %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")
-	}
-
-	fmt.Printf("%s", b.String())
-}
-
-// all returns all combinations for a given string array.
-func all[T any](set []T) (subsets [][]T) {
-	length := uint(len(set))
-	for subsetBits := 1; subsetBits < (1 << length); subsetBits++ {
-		var subset []T
-		for object := uint(0); object < length; object++ {
-			if (subsetBits>>object)&1 == 1 {
-				subset = append(subset, set[object])
-			}
-		}
-		subsets = append(subsets, subset)
-	}
-	return subsets
-}

hooks/sql/options.go

@@ -1,172 +0,0 @@
-package sql
-
-import (
-	"context"
-	"fmt"
-	"time"
-
-	"go.unistack.org/micro/v3/logger"
-	"go.unistack.org/micro/v3/meter"
-	"go.unistack.org/micro/v3/tracer"
-)
-
-var (
-	// DefaultMeterStatsInterval holds default stats interval
-	DefaultMeterStatsInterval = 5 * time.Second
-	// DefaultLoggerObserver used to prepare labels for logger
-	DefaultLoggerObserver = func(ctx context.Context, method string, query string, td time.Duration, err error) []interface{} {
-		labels := []interface{}{"db.method", method, "took", fmt.Sprintf("%v", td)}
-		if err != nil {
-			labels = append(labels, "error", err.Error())
-		}
-		if query != labelUnknown {
-			labels = append(labels, "query", query)
-		}
-		return labels
-	}
-)
-
-var (
-	MaxOpenConnections = "micro_sql_max_open_conn"
-	OpenConnections    = "micro_sql_open_conn"
-	InuseConnections   = "micro_sql_inuse_conn"
-	IdleConnections    = "micro_sql_idle_conn"
-	WaitConnections    = "micro_sql_waited_conn"
-	BlockedSeconds     = "micro_sql_blocked_seconds"
-	MaxIdleClosed      = "micro_sql_max_idle_closed"
-	MaxIdletimeClosed  = "micro_sql_closed_max_idle"
-	MaxLifetimeClosed  = "micro_sql_closed_max_lifetime"
-
-	meterRequestTotal               = "micro_sql_request_total"
-	meterRequestLatencyMicroseconds = "micro_sql_latency_microseconds"
-	meterRequestDurationSeconds     = "micro_sql_request_duration_seconds"
-
-	labelUnknown  = "unknown"
-	labelQuery    = "db_statement"
-	labelMethod   = "db_method"
-	labelStatus   = "status"
-	labelSuccess  = "success"
-	labelFailure  = "failure"
-	labelHost     = "db_host"
-	labelDatabase = "db_name"
-)
-
-// Options struct holds wrapper options
-type Options struct {
-	Logger             logger.Logger
-	Meter              meter.Meter
-	Tracer             tracer.Tracer
-	DatabaseHost       string
-	DatabaseName       string
-	MeterStatsInterval time.Duration
-	LoggerLevel        logger.Level
-	LoggerEnabled      bool
-	LoggerObserver     func(ctx context.Context, method string, name string, td time.Duration, err error) []interface{}
-}
-
-// Option func signature
-type Option func(*Options)
-
-// NewOptions create new Options struct from provided option slice
-func NewOptions(opts ...Option) Options {
-	options := Options{
-		Logger:             logger.DefaultLogger,
-		Meter:              meter.DefaultMeter,
-		Tracer:             tracer.DefaultTracer,
-		MeterStatsInterval: DefaultMeterStatsInterval,
-		LoggerLevel:        logger.ErrorLevel,
-		LoggerObserver:     DefaultLoggerObserver,
-	}
-	for _, o := range opts {
-		o(&options)
-	}
-
-	options.Meter = options.Meter.Clone(
-		meter.Labels(
-			labelHost, options.DatabaseHost,
-			labelDatabase, options.DatabaseName,
-		),
-	)
-
-	options.Logger = options.Logger.Clone(logger.WithAddCallerSkipCount(1))
-
-	return options
-}
-
-// MetricInterval specifies stats interval for *sql.DB
-func MetricInterval(td time.Duration) Option {
-	return func(o *Options) {
-		o.MeterStatsInterval = td
-	}
-}
-
-func DatabaseHost(host string) Option {
-	return func(o *Options) {
-		o.DatabaseHost = host
-	}
-}
-
-func DatabaseName(name string) Option {
-	return func(o *Options) {
-		o.DatabaseName = name
-	}
-}
-
-// Meter passes meter.Meter to wrapper
-func Meter(m meter.Meter) Option {
-	return func(o *Options) {
-		o.Meter = m
-	}
-}
-
-// Logger passes logger.Logger to wrapper
-func Logger(l logger.Logger) Option {
-	return func(o *Options) {
-		o.Logger = l
-	}
-}
-
-// LoggerEnabled enable sql logging
-func LoggerEnabled(b bool) Option {
-	return func(o *Options) {
-		o.LoggerEnabled = b
-	}
-}
-
-// LoggerLevel passes logger.Level option
-func LoggerLevel(lvl logger.Level) Option {
-	return func(o *Options) {
-		o.LoggerLevel = lvl
-	}
-}
-
-// LoggerObserver passes observer to fill logger fields
-func LoggerObserver(obs func(context.Context, string, string, time.Duration, error) []interface{}) Option {
-	return func(o *Options) {
-		o.LoggerObserver = obs
-	}
-}
-
-// Tracer passes tracer.Tracer to wrapper
-func Tracer(t tracer.Tracer) Option {
-	return func(o *Options) {
-		o.Tracer = t
-	}
-}
-
-type queryNameKey struct{}
-
-// QueryName passes query name to wrapper func
-func QueryName(ctx context.Context, name string) context.Context {
-	if ctx == nil {
-		ctx = context.Background()
-	}
-	return context.WithValue(ctx, queryNameKey{}, name)
-}
-
-func getQueryName(ctx context.Context) string {
-	if v, ok := ctx.Value(queryNameKey{}).(string); ok && v != labelUnknown {
-		return v
-	}
-	return getCallerName()
-}

hooks/sql/stats.go

@@ -1,41 +0,0 @@
-package sql
-
-import (
-	"context"
-	"database/sql"
-	"time"
-)
-
-type Statser interface {
-	Stats() sql.DBStats
-}
-
-func NewStatsMeter(ctx context.Context, db Statser, opts ...Option) {
-	options := NewOptions(opts...)
-
-	go func() {
-		ticker := time.NewTicker(options.MeterStatsInterval)
-		defer ticker.Stop()
-
-		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))
-			}
-		}
-	}()
-}

hooks/sql/stmt.go

@@ -1,287 +0,0 @@
-package sql
-
-import (
-	"context"
-	"database/sql/driver"
-	"fmt"
-	"time"
-
-	"go.unistack.org/micro/v3/hooks/requestid"
-	"go.unistack.org/micro/v3/tracer"
-)
-
-var (
-	_ driver.Stmt              = (*wrapperStmt)(nil)
-	_ driver.StmtQueryContext  = (*wrapperStmt)(nil)
-	_ driver.StmtExecContext   = (*wrapperStmt)(nil)
-	_ driver.NamedValueChecker = (*wrapperStmt)(nil)
-)
-
-// wrapperStmt defines a wrapper for driver.Stmt
-type wrapperStmt struct {
-	stmt  driver.Stmt
-	opts  Options
-	query string
-	ctx   context.Context
-}
-
-// Close implements driver.Stmt Close
-func (w *wrapperStmt) Close() error {
-	var ctx context.Context
-	if w.ctx != nil {
-		ctx = w.ctx
-	} else {
-		ctx = context.Background()
-	}
-	_ = ctx
-	labels := []string{labelMethod, "Close"}
-	ts := time.Now()
-	err := w.stmt.Close()
-	td := time.Since(ts)
-	te := td.Seconds()
-	if err != nil {
-		w.opts.Meter.Counter(meterRequestTotal, append(labels, labelStatus, labelFailure)...).Inc()
-	} else {
-		w.opts.Meter.Counter(meterRequestTotal, append(labels, labelStatus, labelSuccess)...).Inc()
-	}
-	w.opts.Meter.Summary(meterRequestLatencyMicroseconds, labels...).Update(te)
-	w.opts.Meter.Histogram(meterRequestDurationSeconds, labels...).Update(te)
-	/*
-		if w.opts.LoggerEnabled && w.opts.Logger.V(w.opts.LoggerLevel) {
-			w.opts.Logger.Log(ctx, w.opts.LoggerLevel, w.opts.LoggerObserver(ctx, "Close", getCallerName(), td, err)...)
-		}
-	*/
-	return err
-}
-
-// NumInput implements driver.Stmt NumInput
-func (w *wrapperStmt) NumInput() int {
-	return w.stmt.NumInput()
-}
-
-// CheckNamedValue implements driver.NamedValueChecker
-func (w *wrapperStmt) CheckNamedValue(v *driver.NamedValue) error {
-	s, ok := w.stmt.(driver.NamedValueChecker)
-	if !ok {
-		return driver.ErrSkip
-	}
-	return s.CheckNamedValue(v)
-}
-
-// Exec implements driver.Stmt Exec
-func (w *wrapperStmt) Exec(args []driver.Value) (driver.Result, error) {
-	var ctx context.Context
-	if w.ctx != nil {
-		ctx = w.ctx
-	} else {
-		ctx = context.Background()
-	}
-	_ = ctx
-	labels := []string{labelMethod, "Exec"}
-	ts := time.Now()
-	res, err := w.stmt.Exec(args) // nolint:staticcheck
-	td := time.Since(ts)
-	te := td.Seconds()
-	if err != nil {
-		w.opts.Meter.Counter(meterRequestTotal, append(labels, labelStatus, labelFailure)...).Inc()
-	} else {
-		w.opts.Meter.Counter(meterRequestTotal, append(labels, labelStatus, labelSuccess)...).Inc()
-	}
-	w.opts.Meter.Summary(meterRequestLatencyMicroseconds, labels...).Update(te)
-	w.opts.Meter.Histogram(meterRequestDurationSeconds, labels...).Update(te)
-	/*
-		if w.opts.LoggerEnabled && w.opts.Logger.V(w.opts.LoggerLevel) {
-			w.opts.Logger.Log(ctx, w.opts.LoggerLevel, w.opts.LoggerObserver(ctx, "Exec", getCallerName(), td, err)...)
-		}
-	*/
-	return res, err
-}
-
-// Query implements driver.Stmt Query
-func (w *wrapperStmt) Query(args []driver.Value) (driver.Rows, error) {
-	var ctx context.Context
-	if w.ctx != nil {
-		ctx = w.ctx
-	} else {
-		ctx = context.Background()
-	}
-	_ = ctx
-	labels := []string{labelMethod, "Query"}
-	ts := time.Now()
-	rows, err := w.stmt.Query(args) // nolint:staticcheck
-	td := time.Since(ts)
-	te := td.Seconds()
-	if err != nil {
-		w.opts.Meter.Counter(meterRequestTotal, append(labels, labelStatus, labelFailure)...).Inc()
-	} else {
-		w.opts.Meter.Counter(meterRequestTotal, append(labels, labelStatus, labelSuccess)...).Inc()
-	}
-	w.opts.Meter.Summary(meterRequestLatencyMicroseconds, labels...).Update(te)
-	w.opts.Meter.Histogram(meterRequestDurationSeconds, labels...).Update(te)
-	/*
-		if w.opts.LoggerEnabled && w.opts.Logger.V(w.opts.LoggerLevel) {
-			w.opts.Logger.Log(ctx, w.opts.LoggerLevel, w.opts.LoggerObserver(ctx, "Query", getCallerName(), td, err)...)
-		}
-	*/
-	return rows, err
-}
-
-// ColumnConverter implements driver.ColumnConverter
-func (w *wrapperStmt) ColumnConverter(idx int) driver.ValueConverter {
-	s, ok := w.stmt.(driver.ColumnConverter) // nolint:staticcheck
-	if !ok {
-		return nil
-	}
-	return s.ColumnConverter(idx)
-}
-
-// ExecContext implements driver.StmtExecContext ExecContext
-func (w *wrapperStmt) ExecContext(ctx context.Context, args []driver.NamedValue) (driver.Result, error) {
-	var nctx context.Context
-	var span tracer.Span
-
-	name := getQueryName(ctx)
-	if w.ctx != nil {
-		nctx, span = w.opts.Tracer.Start(w.ctx, "sdk.database", tracer.WithSpanKind(tracer.SpanKindClient))
-	} else {
-		nctx, span = w.opts.Tracer.Start(ctx, "sdk.database", tracer.WithSpanKind(tracer.SpanKindClient))
-	}
-	span.AddLabels("db.method", "ExecContext")
-	span.AddLabels("db.statement", name)
-	defer span.Finish()
-	if len(args) > 0 {
-		span.AddLabels("db.args", fmt.Sprintf("%v", namedValueToLabels(args)))
-	}
-	if id, ok := ctx.Value(requestid.XRequestIDKey{}).(string); ok {
-		span.AddLabels("x-request-id", id)
-	}
-	labels := []string{labelMethod, "ExecContext", labelQuery, name}
-
-	if conn, ok := w.stmt.(driver.StmtExecContext); ok {
-		ts := time.Now()
-		res, err := conn.ExecContext(nctx, args)
-		td := time.Since(ts)
-		te := td.Seconds()
-		if err != nil {
-			w.opts.Meter.Counter(meterRequestTotal, append(labels, labelStatus, labelFailure)...).Inc()
-			span.SetStatus(tracer.SpanStatusError, err.Error())
-		} else {
-			w.opts.Meter.Counter(meterRequestTotal, append(labels, labelStatus, labelSuccess)...).Inc()
-		}
-		w.opts.Meter.Summary(meterRequestLatencyMicroseconds, labels...).Update(te)
-		w.opts.Meter.Histogram(meterRequestDurationSeconds, labels...).Update(te)
-		/*
-			if w.opts.LoggerEnabled && w.opts.Logger.V(w.opts.LoggerLevel) {
-				w.opts.Logger.Log(ctx, w.opts.LoggerLevel, w.opts.LoggerObserver(ctx, "ExecContext", name, td, err)...)
-			}
-		*/
-		return res, err
-	}
-
-	values, err := namedValueToValue(args)
-	if err != nil {
-		w.opts.Meter.Counter(meterRequestTotal, append(labels, labelStatus, labelFailure)...).Inc()
-		span.SetStatus(tracer.SpanStatusError, err.Error())
-		/*
-			if w.opts.LoggerEnabled && w.opts.Logger.V(w.opts.LoggerLevel) {
-				w.opts.Logger.Log(ctx, w.opts.LoggerLevel, w.opts.LoggerObserver(ctx, "ExecContext", name, 0, err)...)
-			}
-		*/
-		return nil, err
-	}
-	ts := time.Now()
-	res, err := w.Exec(values) // nolint:staticcheck
-	td := time.Since(ts)
-	te := td.Seconds()
-	if err != nil {
-		w.opts.Meter.Counter(meterRequestTotal, append(labels, labelStatus, labelFailure)...).Inc()
-		span.SetStatus(tracer.SpanStatusError, err.Error())
-	} else {
-		w.opts.Meter.Counter(meterRequestTotal, append(labels, labelStatus, labelSuccess)...).Inc()
-	}
-
-	w.opts.Meter.Summary(meterRequestLatencyMicroseconds, labels...).Update(te)
-	w.opts.Meter.Histogram(meterRequestDurationSeconds, labels...).Update(te)
-	/*
-		if w.opts.LoggerEnabled && w.opts.Logger.V(w.opts.LoggerLevel) {
-			w.opts.Logger.Log(ctx, w.opts.LoggerLevel, w.opts.LoggerObserver(ctx, "ExecContext", name, td, err)...)
-		}
-	*/
-	return res, err
-}
-
-// QueryContext implements driver.StmtQueryContext StmtQueryContext
-func (w *wrapperStmt) QueryContext(ctx context.Context, args []driver.NamedValue) (driver.Rows, error) {
-	var nctx context.Context
-	var span tracer.Span
-
-	name := getQueryName(ctx)
-	if w.ctx != nil {
-		nctx, span = w.opts.Tracer.Start(w.ctx, "sdk.database", tracer.WithSpanKind(tracer.SpanKindClient))
-	} else {
-		nctx, span = w.opts.Tracer.Start(ctx, "sdk.database", tracer.WithSpanKind(tracer.SpanKindClient))
-	}
-	span.AddLabels("db.method", "QueryContext")
-	span.AddLabels("db.statement", name)
-	defer span.Finish()
-	if len(args) > 0 {
-		span.AddLabels("db.args", fmt.Sprintf("%v", namedValueToLabels(args)))
-	}
-	if id, ok := ctx.Value(requestid.XRequestIDKey{}).(string); ok {
-		span.AddLabels("x-request-id", id)
-	}
-	labels := []string{labelMethod, "QueryContext", labelQuery, name}
-	if conn, ok := w.stmt.(driver.StmtQueryContext); ok {
-		ts := time.Now()
-		rows, err := conn.QueryContext(nctx, args)
-		td := time.Since(ts)
-		te := td.Seconds()
-		if err != nil {
-			w.opts.Meter.Counter(meterRequestTotal, append(labels, labelStatus, labelFailure)...).Inc()
-			span.SetStatus(tracer.SpanStatusError, err.Error())
-		} else {
-			w.opts.Meter.Counter(meterRequestTotal, append(labels, labelStatus, labelSuccess)...).Inc()
-		}
-
-		w.opts.Meter.Summary(meterRequestLatencyMicroseconds, labels...).Update(te)
-		w.opts.Meter.Histogram(meterRequestDurationSeconds, labels...).Update(te)
-		/*
-			if w.opts.LoggerEnabled && w.opts.Logger.V(w.opts.LoggerLevel) {
-				w.opts.Logger.Log(ctx, w.opts.LoggerLevel, w.opts.LoggerObserver(ctx, "QueryContext", name, td, err)...)
-			}
-		*/
-		return rows, err
-	}
-
-	values, err := namedValueToValue(args)
-	if err != nil {
-		w.opts.Meter.Counter(meterRequestTotal, append(labels, labelStatus, labelFailure)...).Inc()
-
-		span.SetStatus(tracer.SpanStatusError, err.Error())
-		/*
-			if w.opts.LoggerEnabled && w.opts.Logger.V(w.opts.LoggerLevel) {
-				w.opts.Logger.Log(ctx, w.opts.LoggerLevel, w.opts.LoggerObserver(ctx, "QueryContext", name, 0, err)...)
-			}
-		*/
-		return nil, err
-	}
-	ts := time.Now()
-	rows, err := w.Query(values) // nolint:staticcheck
-	td := time.Since(ts)
-	te := td.Seconds()
-	if err != nil {
-		w.opts.Meter.Counter(meterRequestTotal, append(labels, labelStatus, labelFailure)...).Inc()
-		span.SetStatus(tracer.SpanStatusError, err.Error())
-	} else {
-		w.opts.Meter.Counter(meterRequestTotal, append(labels, labelStatus, labelSuccess)...).Inc()
-	}
-
-	w.opts.Meter.Summary(meterRequestLatencyMicroseconds, labels...).Update(te)
-	w.opts.Meter.Histogram(meterRequestDurationSeconds, labels...).Update(te)
-	/*
-		if w.opts.LoggerEnabled && w.opts.Logger.V(w.opts.LoggerLevel) {
-			w.opts.Logger.Log(ctx, w.opts.LoggerLevel, w.opts.LoggerObserver(ctx, "QueryContext", name, td, err)...)
-		}
-	*/
-	return rows, err
-}

hooks/sql/tx.go

@@ -1,63 +0,0 @@
-package sql
-
-import (
-	"context"
-	"database/sql/driver"
-	"time"
-
-	"go.unistack.org/micro/v3/tracer"
-)
-
-var _ driver.Tx = (*wrapperTx)(nil)
-
-// wrapperTx defines a wrapper for driver.Tx
-type wrapperTx struct {
-	tx   driver.Tx
-	span tracer.Span
-	opts Options
-	ctx  context.Context
-}
-
-// Commit implements driver.Tx Commit
-func (w *wrapperTx) Commit() error {
-	ts := time.Now()
-	err := w.tx.Commit()
-	td := time.Since(ts)
-	_ = td
-	if w.span != nil {
-		if err != nil {
-			w.span.SetStatus(tracer.SpanStatusError, err.Error())
-		}
-		w.span.Finish()
-	}
-	/*
-		if w.opts.LoggerEnabled && w.opts.Logger.V(w.opts.LoggerLevel) {
-			w.opts.Logger.Log(w.ctx, w.opts.LoggerLevel, w.opts.LoggerObserver(w.ctx, "Commit", getCallerName(), td, err)...)
-		}
-	*/
-	w.ctx = nil
-
-	return err
-}
-
-// Rollback implements driver.Tx Rollback
-func (w *wrapperTx) Rollback() error {
-	ts := time.Now()
-	err := w.tx.Rollback()
-	td := time.Since(ts)
-	_ = td
-	if w.span != nil {
-		if err != nil {
-			w.span.SetStatus(tracer.SpanStatusError, err.Error())
-		}
-		w.span.Finish()
-	}
-	/*
-		if w.opts.LoggerEnabled && w.opts.Logger.V(w.opts.LoggerLevel) {
-			w.opts.Logger.Log(w.ctx, w.opts.LoggerLevel, w.opts.LoggerObserver(w.ctx, "Rollback", getCallerName(), td, err)...)
-		}
-	*/
-	w.ctx = nil
-
-	return err
-}

hooks/sql/wrap.go

@@ -1,19 +0,0 @@
-package sql
-
-import (
-	"database/sql/driver"
-)
-
-/*
-func wrapDriver(d driver.Driver, opts Options) driver.Driver {
-	if _, ok := d.(driver.DriverContext); ok {
-		return &wrapperDriver{driver: d, opts: opts}
-	}
-	return struct{ driver.Driver }{&wrapperDriver{driver: d, opts: opts}}
-}
-*/
-
-// WrapConn allows an existing driver.Conn to be wrapped.
-func WrapConn(c driver.Conn, opts ...Option) driver.Conn {
-	return wrapConn(c, NewOptions(opts...))
-}

hooks/validator/validator.go

@@ -1,194 +0,0 @@
-package validator
-
-import (
-	"context"
-
-	"go.unistack.org/micro/v3/client"
-	"go.unistack.org/micro/v3/errors"
-	"go.unistack.org/micro/v3/server"
-)
-
-var (
-	DefaultClientErrorFunc = func(req client.Request, rsp interface{}, err error) error {
-		if rsp != nil {
-			return errors.BadGateway(req.Service(), "%v", err)
-		}
-		return errors.BadRequest(req.Service(), "%v", err)
-	}
-
-	DefaultServerErrorFunc = func(req server.Request, rsp interface{}, err error) error {
-		if rsp != nil {
-			return errors.BadGateway(req.Service(), "%v", err)
-		}
-		return errors.BadRequest(req.Service(), "%v", err)
-	}
-
-	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
-)
-
-// Options struct holds wrapper options
-type Options struct {
-	ClientErrorFn          ClientErrorFunc
-	ServerErrorFn          ServerErrorFunc
-	PublishErrorFn         PublishErrorFunc
-	SubscribeErrorFn       SubscribeErrorFunc
-	ClientValidateResponse bool
-	ServerValidateResponse bool
-}
-
-// Option func signature
-type Option func(*Options)
-
-func ClientValidateResponse(b bool) Option {
-	return func(o *Options) {
-		o.ClientValidateResponse = b
-	}
-}
-
-func ServerValidateResponse(b bool) Option {
-	return func(o *Options) {
-		o.ClientValidateResponse = b
-	}
-}
-
-func ClientReqErrorFn(fn ClientErrorFunc) Option {
-	return func(o *Options) {
-		o.ClientErrorFn = fn
-	}
-}
-
-func ServerErrorFn(fn ServerErrorFunc) Option {
-	return func(o *Options) {
-		o.ServerErrorFn = fn
-	}
-}
-
-func 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,
-	}
-	for _, o := range opts {
-		o(&options)
-	}
-	return options
-}
-
-func NewHook(opts ...Option) *hook {
-	return &hook{opts: NewOptions(opts...)}
-}
-
-type validator interface {
-	Validate() error
-}
-
-type hook struct {
-	opts Options
-}
-
-func (w *hook) ClientCall(next client.FuncCall) client.FuncCall {
-	return func(ctx context.Context, req client.Request, rsp interface{}, opts ...client.CallOption) error {
-		if v, ok := req.Body().(validator); ok {
-			if err := v.Validate(); err != nil {
-				return w.opts.ClientErrorFn(req, nil, err)
-			}
-		}
-		err := next(ctx, req, rsp, opts...)
-		if v, ok := rsp.(validator); ok && w.opts.ClientValidateResponse {
-			if verr := v.Validate(); verr != nil {
-				return w.opts.ClientErrorFn(req, rsp, verr)
-			}
-		}
-		return err
-	}
-}
-
-func (w *hook) ClientStream(next client.FuncStream) client.FuncStream {
-	return func(ctx context.Context, req client.Request, opts ...client.CallOption) (client.Stream, error) {
-		if v, ok := req.Body().(validator); ok {
-			if err := v.Validate(); err != nil {
-				return nil, w.opts.ClientErrorFn(req, nil, err)
-			}
-		}
-		return next(ctx, req, opts...)
-	}
-}
-
-func (w *hook) 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 {
-			if err := v.Validate(); err != nil {
-				return w.opts.ServerErrorFn(req, nil, err)
-			}
-		}
-		err := next(ctx, req, rsp)
-		if v, ok := rsp.(validator); ok && w.opts.ServerValidateResponse {
-			if verr := v.Validate(); verr != nil {
-				return w.opts.ServerErrorFn(req, rsp, verr)
-			}
-		}
-		return err
-	}
-}
-
-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/options.go

@@ -8,7 +8,7 @@ import (
 	"slices"
 	"time"
 
-	"go.unistack.org/micro/v3/meter"
+	"go.unistack.org/micro/v4/meter"
 )
 
 // Option func signature
@@ -99,7 +99,6 @@ func WithAddFields(fields ...interface{}) Option {
 					iv, iok := o.Fields[i].(string)
 					jv, jok := fields[j].(string)
 					if iok && jok && iv == jv {
-						o.Fields[i+1] = fields[j+1]
 						fields = slices.Delete(fields, j, j+2)
 					}
 				}

logger/slog/slog.go

@@ -13,9 +13,9 @@ import (
 	"sync/atomic"
 	"time"
 
-	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v4/logger"
-	"go.unistack.org/micro/v3/semconv"
+	"go.unistack.org/micro/v4/semconv"
-	"go.unistack.org/micro/v3/tracer"
+	"go.unistack.org/micro/v4/tracer"
 )
 
 const (
@@ -278,7 +278,7 @@ func (s *slogLogger) printLog(ctx context.Context, lvl logger.Level, msg string,
 		}
 	}
 
-	if s.opts.AddStacktrace && (lvl == logger.FatalLevel || lvl == logger.ErrorLevel) {
+	if (s.opts.AddStacktrace || lvl == logger.FatalLevel) || (s.opts.AddStacktrace && lvl == logger.ErrorLevel) {
 		stackInfo := make([]byte, 1024*1024)
 		if stackSize := runtime.Stack(stackInfo, false); stackSize > 0 {
 			traceLines := reTrace.Split(string(stackInfo[:stackSize]), -1)

logger/slog/slog_test.go

@@ -12,16 +12,16 @@ import (
 	"time"
 
 	"github.com/google/uuid"
-	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v4/logger"
-	"go.unistack.org/micro/v3/metadata"
+	"go.unistack.org/micro/v4/metadata"
-	"go.unistack.org/micro/v3/util/buffer"
+	"go.unistack.org/micro/v4/util/buffer"
 )
 
 // always first to have proper check
 func TestStacktrace(t *testing.T) {
 	ctx := context.TODO()
 	buf := bytes.NewBuffer(nil)
-	l := NewLogger(logger.WithLevel(logger.DebugLevel), logger.WithOutput(buf),
+	l := NewLogger(logger.WithLevel(logger.ErrorLevel), logger.WithOutput(buf),
 		WithHandlerFunc(slog.NewTextHandler),
 		logger.WithAddStacktrace(true),
 	)
@@ -124,7 +124,7 @@ func TestWithDedupKeysWithAddFields(t *testing.T) {
 
 	l.Info(ctx, "msg3")
 
-	if !bytes.Contains(buf.Bytes(), []byte(`msg=msg3 key1=val4 key2=val3`)) {
+	if !bytes.Contains(buf.Bytes(), []byte(`msg=msg3 key1=val1 key2=val2`)) {
 		t.Fatalf("logger error not works, buf contains: %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

@@ -1,3 +1,5 @@
+//go:build !exclude
+
 // Package metadata is a way of defining message headers
 package metadata
 

metadata/metadata.go

@@ -1,3 +1,5 @@
+//go:build !exclude
+
 // Package metadata is a way of defining message headers
 package metadata
 

metadata/metadata_grpc.go

@@ -0,0 +1,282 @@
+//go:build exclude
+
+// Package metadata TODO need compare with micro metadata
+package metadata // import "google.golang.org/grpc/metadata"
+
+import (
+	"context"
+	"fmt"
+	"strings"
+)
+
+// MD is a mapping from metadata keys to values. Users should use the following
+// two convenience functions New and Pairs to generate MD.
+type MD map[string][]string
+
+type Metadata map[string]string
+
+// New creates an MD from a given key-value map.
+//
+// Only the following ASCII characters are allowed in keys:
+//   - digits: 0-9
+//   - uppercase letters: A-Z (normalized to lower)
+//   - lowercase letters: a-z
+//   - special characters: -_.
+//
+// Uppercase letters are automatically converted to lowercase.
+//
+// Keys beginning with "grpc-" are reserved for grpc-internal use only and may
+// result in errors if set in metadata.
+func New(m map[string]string) MD {
+	md := make(MD, len(m))
+	for k, val := range m {
+		key := strings.ToLower(k)
+		md[key] = append(md[key], val)
+	}
+	return md
+}
+
+// Pairs returns an MD formed by the mapping of key, value ...
+// Pairs panics if len(kv) is odd.
+//
+// Only the following ASCII characters are allowed in keys:
+//   - digits: 0-9
+//   - uppercase letters: A-Z (normalized to lower)
+//   - lowercase letters: a-z
+//   - special characters: -_.
+//
+// Uppercase letters are automatically converted to lowercase.
+//
+// Keys beginning with "grpc-" are reserved for grpc-internal use only and may
+// result in errors if set in metadata.
+func Pairs(kv ...string) MD {
+	if len(kv)%2 == 1 {
+		panic(fmt.Sprintf("metadata: Pairs got the odd number of input pairs for metadata: %d", len(kv)))
+	}
+	md := make(MD, len(kv)/2)
+	for i := 0; i < len(kv); i += 2 {
+		key := strings.ToLower(kv[i])
+		md[key] = append(md[key], kv[i+1])
+	}
+	return md
+}
+
+// Len returns the number of items in md.
+func (md MD) Len() int {
+	return len(md)
+}
+
+// Copy returns a copy of md.
+func (md MD) Copy() MD {
+	out := make(MD, len(md))
+	for k, v := range md {
+		out[k] = copyOf(v)
+	}
+	return out
+}
+
+// Get obtains the values for a given key.
+//
+// k is converted to lowercase before searching in md.
+func (md MD) Get(k string) []string {
+	k = strings.ToLower(k)
+	return md[k]
+}
+
+// Set sets the value of a given key with a slice of values.
+//
+// k is converted to lowercase before storing in md.
+func (md MD) Set(k string, vals ...string) {
+	if len(vals) == 0 {
+		return
+	}
+	k = strings.ToLower(k)
+	md[k] = vals
+}
+
+// Append adds the values to key k, not overwriting what was already stored at
+// that key.
+//
+// k is converted to lowercase before storing in md.
+func (md MD) Append(k string, vals ...string) {
+	if len(vals) == 0 {
+		return
+	}
+	k = strings.ToLower(k)
+	md[k] = append(md[k], vals...)
+}
+
+// Delete removes the values for a given key k which is converted to lowercase
+// before removing it from md.
+func (md MD) Delete(k string) {
+	k = strings.ToLower(k)
+	delete(md, k)
+}
+
+// Join joins any number of mds into a single MD.
+//
+// The order of values for each key is determined by the order in which the mds
+// containing those values are presented to Join.
+func Join(mds ...MD) MD {
+	out := MD{}
+	for _, md := range mds {
+		for k, v := range md {
+			out[k] = append(out[k], v...)
+		}
+	}
+	return out
+}
+
+type mdIncomingKey struct{}
+type mdOutgoingKey struct{}
+
+// NewIncomingContext creates a new context with incoming md attached. md must
+// not be modified after calling this function.
+func NewIncomingContext(ctx context.Context, md Metadata) context.Context {
+	in := make(MD, len(md))
+	for k, v := range md {
+		in[k] = []string{v}
+	}
+
+	return context.WithValue(ctx, mdIncomingKey{}, in)
+}
+
+// NewOutgoingContext creates a new context with outgoing md attached. If used
+// in conjunction with AppendToOutgoingContext, NewOutgoingContext will
+// overwrite any previously-appended metadata. md must not be modified after
+// calling this function.
+func NewOutgoingContext(ctx context.Context, md Metadata) context.Context {
+	out := make(MD, len(md))
+	for k, v := range md {
+		out[k] = []string{v}
+	}
+
+	return context.WithValue(ctx, mdOutgoingKey{}, rawMD{md: out})
+}
+
+// AppendToOutgoingContext returns a new context with the provided kv merged
+// with any existing metadata in the context. Please refer to the documentation
+// of Pairs for a description of kv.
+func AppendToOutgoingContext(ctx context.Context, kv ...string) context.Context {
+	if len(kv)%2 == 1 {
+		panic(fmt.Sprintf("metadata: AppendToOutgoingContext got an odd number of input pairs for metadata: %d", len(kv)))
+	}
+	md, _ := ctx.Value(mdOutgoingKey{}).(rawMD)
+	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, mdOutgoingKey{}, rawMD{md: md.md, added: added})
+}
+
+// FromIncomingContext returns the incoming metadata in ctx if it exists.
+//
+// All keys in the returned MD are lowercase.
+func FromIncomingContext(ctx context.Context) (Metadata, bool) {
+	md, ok := ctx.Value(mdIncomingKey{}).(MD)
+	if !ok {
+		return nil, false
+	}
+	out := make(Metadata, len(md))
+	for k, v := range md {
+		// We need to manually convert all keys to lower case, because MD is a
+		// map, and there's no guarantee that the MD attached to the context is
+		// created using our helper functions.
+
+		if len(v) > 0 {
+			key := strings.ToLower(k)
+			out[key] = v[0]
+		}
+
+	}
+	return out, true
+}
+
+// ValueFromIncomingContext returns the metadata value corresponding to the metadata
+// key from the incoming metadata if it exists. Keys are matched in a case insensitive
+// manner.
+func ValueFromIncomingContext(ctx context.Context, key string) []string {
+	md, ok := ctx.Value(mdIncomingKey{}).(MD)
+	if !ok {
+		return nil
+	}
+
+	if v, ok := md[key]; ok {
+		return copyOf(v)
+	}
+	for k, v := range md {
+		// Case insensitive comparison: MD is a map, and there's no guarantee
+		// that the MD attached to the context is created using our helper
+		// functions.
+		if strings.EqualFold(k, key) {
+			return copyOf(v)
+		}
+	}
+	return nil
+}
+
+func copyOf(v []string) []string {
+	vals := make([]string, len(v))
+	copy(vals, v)
+	return vals
+}
+
+// fromOutgoingContextRaw returns the un-merged, intermediary contents of rawMD.
+//
+// Remember to perform strings.ToLower on the keys, for both the returned MD (MD
+// is a map, there's no guarantee it's created using our helper functions) and
+// the extra kv pairs (AppendToOutgoingContext doesn't turn them into
+// lowercase).
+func fromOutgoingContextRaw(ctx context.Context) (MD, [][]string, bool) {
+	raw, ok := ctx.Value(mdOutgoingKey{}).(rawMD)
+	if !ok {
+		return nil, nil, false
+	}
+
+	return raw.md, raw.added, true
+}
+
+// FromOutgoingContext returns the outgoing metadata in ctx if it exists.
+//
+// All keys in the returned MD are lowercase.
+func FromOutgoingContext(ctx context.Context) (Metadata, bool) {
+	raw, ok := ctx.Value(mdOutgoingKey{}).(rawMD)
+	if !ok {
+		return nil, false
+	}
+
+	mdSize := len(raw.md)
+	for i := range raw.added {
+		mdSize += len(raw.added[i]) / 2
+	}
+
+	out := make(Metadata, mdSize)
+	for k, v := range raw.md {
+		// We need to manually convert all keys to lower case, because MD is a
+		// map, and there's no guarantee that the MD attached to the context is
+		// created using our helper functions.
+		if len(v) > 0 {
+			key := strings.ToLower(k)
+			out[key] = v[0]
+		}
+	}
+	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 {
+			key := strings.ToLower(added[i])
+			out[key] = added[i+1]
+		}
+	}
+	return out, ok
+}
+
+type rawMD struct {
+	md    MD
+	added [][]string
+}

micro.go

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

micro_test.go

@@ -6,8 +6,8 @@ import (
 	"reflect"
 	"testing"
 
-	"go.unistack.org/micro/v3/broker"
+	"go.unistack.org/micro/v4/broker"
-	"go.unistack.org/micro/v3/fsm"
+	"go.unistack.org/micro/v4/fsm"
 )
 
 func TestAs(t *testing.T) {

network/network.go

@@ -2,8 +2,8 @@
 package network
 
 import (
-	"go.unistack.org/micro/v3/client"
+	"go.unistack.org/micro/v4/client"
-	"go.unistack.org/micro/v3/server"
+	"go.unistack.org/micro/v4/server"
 )
 
 // Error is network node errors

network/options.go

@@ -1,13 +1,13 @@
 package network
 
 import (
-	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v4/logger"
-	"go.unistack.org/micro/v3/meter"
+	"go.unistack.org/micro/v4/meter"
-	"go.unistack.org/micro/v3/network/tunnel"
+	"go.unistack.org/micro/v4/network/tunnel"
-	"go.unistack.org/micro/v3/proxy"
+	"go.unistack.org/micro/v4/proxy"
-	"go.unistack.org/micro/v3/router"
+	"go.unistack.org/micro/v4/router"
-	"go.unistack.org/micro/v3/tracer"
+	"go.unistack.org/micro/v4/tracer"
-	"go.unistack.org/micro/v3/util/id"
+	"go.unistack.org/micro/v4/util/id"
 )
 
 // Option func

network/transport/memory.go

@@ -8,9 +8,9 @@ import (
 	"sync"
 	"time"
 
-	maddr "go.unistack.org/micro/v3/util/addr"
+	maddr "go.unistack.org/micro/v4/util/addr"
-	mnet "go.unistack.org/micro/v3/util/net"
+	mnet "go.unistack.org/micro/v4/util/net"
-	"go.unistack.org/micro/v3/util/rand"
+	"go.unistack.org/micro/v4/util/rand"
 )
 
 type memorySocket struct {

network/transport/options.go

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

network/transport/transport.go

@@ -5,7 +5,7 @@ import (
 	"context"
 	"time"
 
-	"go.unistack.org/micro/v3/metadata"
+	"go.unistack.org/micro/v4/metadata"
 )
 
 var (

network/tunnel/broker/broker.go

@@ -5,11 +5,11 @@ import (
 	"context"
 	"fmt"
 
-	"go.unistack.org/micro/v3/broker"
+	"go.unistack.org/micro/v4/broker"
-	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v4/logger"
-	"go.unistack.org/micro/v3/metadata"
+	"go.unistack.org/micro/v4/metadata"
-	"go.unistack.org/micro/v3/network/transport"
+	"go.unistack.org/micro/v4/network/transport"
-	"go.unistack.org/micro/v3/network/tunnel"
+	"go.unistack.org/micro/v4/network/tunnel"
 )
 
 type tunBroker struct {

network/tunnel/options.go

@@ -3,11 +3,11 @@ package tunnel
 import (
 	"time"
 
-	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v4/logger"
-	"go.unistack.org/micro/v3/meter"
+	"go.unistack.org/micro/v4/meter"
-	"go.unistack.org/micro/v3/network/transport"
+	"go.unistack.org/micro/v4/network/transport"
-	"go.unistack.org/micro/v3/tracer"
+	"go.unistack.org/micro/v4/tracer"
-	"go.unistack.org/micro/v3/util/id"
+	"go.unistack.org/micro/v4/util/id"
 )
 
 var (

network/tunnel/transport/listener.go

@@ -1,8 +1,8 @@
 package transport
 
 import (
-	"go.unistack.org/micro/v3/network/transport"
+	"go.unistack.org/micro/v4/network/transport"
-	"go.unistack.org/micro/v3/network/tunnel"
+	"go.unistack.org/micro/v4/network/tunnel"
 )
 
 type tunListener struct {

network/tunnel/transport/transport.go

@@ -5,8 +5,8 @@ import (
 	"context"
 	"fmt"
 
-	"go.unistack.org/micro/v3/network/transport"
+	"go.unistack.org/micro/v4/network/transport"
-	"go.unistack.org/micro/v3/network/tunnel"
+	"go.unistack.org/micro/v4/network/tunnel"
 )
 
 type tunTransport struct {

network/tunnel/tunnel.go

@@ -6,7 +6,7 @@ import (
 	"errors"
 	"time"
 
-	"go.unistack.org/micro/v3/network/transport"
+	"go.unistack.org/micro/v4/network/transport"
 )
 
 // DefaultTunnel contains default tunnel implementation

options.go

@@ -5,17 +5,17 @@ import (
 	"fmt"
 	"time"
 
-	"go.unistack.org/micro/v3/broker"
+	"go.unistack.org/micro/v4/broker"
-	"go.unistack.org/micro/v3/client"
+	"go.unistack.org/micro/v4/client"
-	"go.unistack.org/micro/v3/config"
+	"go.unistack.org/micro/v4/config"
-	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v4/logger"
-	"go.unistack.org/micro/v3/metadata"
+	"go.unistack.org/micro/v4/metadata"
-	"go.unistack.org/micro/v3/meter"
+	"go.unistack.org/micro/v4/meter"
-	"go.unistack.org/micro/v3/register"
+	"go.unistack.org/micro/v4/register"
-	"go.unistack.org/micro/v3/router"
+	"go.unistack.org/micro/v4/router"
-	"go.unistack.org/micro/v3/server"
+	"go.unistack.org/micro/v4/server"
-	"go.unistack.org/micro/v3/store"
+	"go.unistack.org/micro/v4/store"
-	"go.unistack.org/micro/v3/tracer"
+	"go.unistack.org/micro/v4/tracer"
 )
 
 // Options for micro service

profiler/http/http.go

@@ -7,7 +7,7 @@ import (
 	"net/http/pprof"
 	"sync"
 
-	profile "go.unistack.org/micro/v3/profiler"
+	profile "go.unistack.org/micro/v4/profiler"
 )
 
 type httpProfile struct {

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 {

proxy/options.go

@@ -2,11 +2,11 @@
 package proxy
 
 import (
-	"go.unistack.org/micro/v3/client"
+	"go.unistack.org/micro/v4/client"
-	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v4/logger"
-	"go.unistack.org/micro/v3/meter"
+	"go.unistack.org/micro/v4/meter"
-	"go.unistack.org/micro/v3/router"
+	"go.unistack.org/micro/v4/router"
-	"go.unistack.org/micro/v3/tracer"
+	"go.unistack.org/micro/v4/tracer"
 )
 
 // Options for proxy

proxy/proxy.go

@@ -4,7 +4,7 @@ package proxy
 import (
 	"context"
 
-	"go.unistack.org/micro/v3/server"
+	"go.unistack.org/micro/v4/server"
 )
 
 // DefaultEndpoint holds default proxy address

register/memory/memory.go

@@ -6,9 +6,9 @@ import (
 	"sync"
 	"time"
 
-	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v4/logger"
-	"go.unistack.org/micro/v3/register"
+	"go.unistack.org/micro/v4/register"
-	"go.unistack.org/micro/v3/util/id"
+	"go.unistack.org/micro/v4/util/id"
 )
 
 var (

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/v4/codec"
-	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v4/logger"
-	"go.unistack.org/micro/v3/meter"
+	"go.unistack.org/micro/v4/meter"
-	"go.unistack.org/micro/v3/tracer"
+	"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 (

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

resolver/registry/registry.go

@@ -4,8 +4,8 @@ package register
 import (
 	"context"
 
-	"go.unistack.org/micro/v3/register"
+	"go.unistack.org/micro/v4/register"
-	"go.unistack.org/micro/v3/resolver"
+	"go.unistack.org/micro/v4/resolver"
 )
 
 // Resolver is a register network resolver

resolver/static/static.go

@@ -2,7 +2,7 @@
 package static
 
 import (
-	"go.unistack.org/micro/v3/resolver"
+	"go.unistack.org/micro/v4/resolver"
 )
 
 // Resolver returns a static list of nodes. In the event the node list

router/options.go

@@ -3,9 +3,9 @@ package router
 import (
 	"context"
 
-	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v4/logger"
-	"go.unistack.org/micro/v3/register"
+	"go.unistack.org/micro/v4/register"
-	"go.unistack.org/micro/v3/util/id"
+	"go.unistack.org/micro/v4/util/id"
 )
 
 // Options are router options

router/route.go

@@ -3,7 +3,7 @@ package router
 import (
 	"hash/fnv"
 
-	"go.unistack.org/micro/v3/metadata"
+	"go.unistack.org/micro/v4/metadata"
 )
 
 var (

selector/random/random.go

@@ -1,8 +1,8 @@
 package random
 
 import (
-	"go.unistack.org/micro/v3/selector"
+	"go.unistack.org/micro/v4/selector"
-	"go.unistack.org/micro/v3/util/rand"
+	"go.unistack.org/micro/v4/util/rand"
 )
 
 type random struct{}

selector/random/random_test.go

@@ -3,7 +3,7 @@ package random
 import (
 	"testing"
 
-	"go.unistack.org/micro/v3/selector"
+	"go.unistack.org/micro/v4/selector"
 )
 
 func TestRandom(t *testing.T) {

selector/roundrobin/roundrobin.go

@@ -1,8 +1,8 @@
 package roundrobin
 
 import (
-	"go.unistack.org/micro/v3/selector"
+	"go.unistack.org/micro/v4/selector"
-	"go.unistack.org/micro/v3/util/rand"
+	"go.unistack.org/micro/v4/util/rand"
 )
 
 // NewSelector returns an initialised round robin selector

selector/roundrobin/roundrobin_test.go

@@ -3,7 +3,7 @@ package roundrobin
 import (
 	"testing"
 
-	"go.unistack.org/micro/v3/selector"
+	"go.unistack.org/micro/v4/selector"
 )
 
 func TestRoundRobin(t *testing.T) {

server/errors.go

@@ -1,6 +1,6 @@
 package server
 
-import "go.unistack.org/micro/v3/errors"
+import "go.unistack.org/micro/v4/errors"
 
 type Error struct {
 	id string

server/errors_test.go

@@ -3,7 +3,7 @@ package server
 import (
 	"testing"
 
-	"go.unistack.org/micro/v3/errors"
+	"go.unistack.org/micro/v4/errors"
 )
 
 func TestError(t *testing.T) {

server/noop.go

@@ -9,16 +9,16 @@ import (
 	"sync"
 	"time"
 
-	"go.unistack.org/micro/v3/broker"
+	"go.unistack.org/micro/v4/broker"
-	"go.unistack.org/micro/v3/codec"
+	"go.unistack.org/micro/v4/codec"
-	"go.unistack.org/micro/v3/errors"
+	"go.unistack.org/micro/v4/errors"
-	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v4/logger"
-	"go.unistack.org/micro/v3/metadata"
+	"go.unistack.org/micro/v4/metadata"
-	"go.unistack.org/micro/v3/options"
+	"go.unistack.org/micro/v4/options"
-	"go.unistack.org/micro/v3/register"
+	"go.unistack.org/micro/v4/register"
-	maddr "go.unistack.org/micro/v3/util/addr"
+	maddr "go.unistack.org/micro/v4/util/addr"
-	mnet "go.unistack.org/micro/v3/util/net"
+	mnet "go.unistack.org/micro/v4/util/net"
-	"go.unistack.org/micro/v3/util/rand"
+	"go.unistack.org/micro/v4/util/rand"
 )
 
 // DefaultCodecs will be used to encode/decode

server/noop_test.go

@@ -5,12 +5,12 @@ import (
 	"fmt"
 	"testing"
 
-	"go.unistack.org/micro/v3/broker"
+	"go.unistack.org/micro/v4/broker"
-	"go.unistack.org/micro/v3/client"
+	"go.unistack.org/micro/v4/client"
-	"go.unistack.org/micro/v3/codec"
+	"go.unistack.org/micro/v4/codec"
-	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v4/logger"
-	"go.unistack.org/micro/v3/options"
+	"go.unistack.org/micro/v4/options"
-	"go.unistack.org/micro/v3/server"
+	"go.unistack.org/micro/v4/server"
 )
 
 type TestHandler struct {

server/options.go

@@ -7,16 +7,16 @@ import (
 	"sync"
 	"time"
 
-	"go.unistack.org/micro/v3/broker"
+	"go.unistack.org/micro/v4/broker"
-	"go.unistack.org/micro/v3/codec"
+	"go.unistack.org/micro/v4/codec"
-	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v4/logger"
-	"go.unistack.org/micro/v3/metadata"
+	"go.unistack.org/micro/v4/metadata"
-	"go.unistack.org/micro/v3/meter"
+	"go.unistack.org/micro/v4/meter"
-	"go.unistack.org/micro/v3/options"
+	"go.unistack.org/micro/v4/options"
-	"go.unistack.org/micro/v3/register"
+	"go.unistack.org/micro/v4/register"
-	msync "go.unistack.org/micro/v3/sync"
+	msync "go.unistack.org/micro/v4/sync"
-	"go.unistack.org/micro/v3/tracer"
+	"go.unistack.org/micro/v4/tracer"
-	"go.unistack.org/micro/v3/util/id"
+	"go.unistack.org/micro/v4/util/id"
 )
 
 // Option func

server/registry.go

@@ -4,10 +4,10 @@ import (
 	"net"
 	"time"
 
-	"go.unistack.org/micro/v3/metadata"
+	"go.unistack.org/micro/v4/metadata"
-	"go.unistack.org/micro/v3/register"
+	"go.unistack.org/micro/v4/register"
-	"go.unistack.org/micro/v3/util/addr"
+	"go.unistack.org/micro/v4/util/addr"
-	"go.unistack.org/micro/v3/util/backoff"
+	"go.unistack.org/micro/v4/util/backoff"
 )
 
 var (

server/server.go

@@ -5,8 +5,8 @@ import (
 	"context"
 	"time"
 
-	"go.unistack.org/micro/v3/codec"
+	"go.unistack.org/micro/v4/codec"
-	"go.unistack.org/micro/v3/metadata"
+	"go.unistack.org/micro/v4/metadata"
 )
 
 // DefaultServer default server

service.go

@@ -9,17 +9,17 @@ import (
 
 	"github.com/KimMachineGun/automemlimit/memlimit"
 	"go.uber.org/automaxprocs/maxprocs"
-	"go.unistack.org/micro/v3/broker"
+	"go.unistack.org/micro/v4/broker"
-	"go.unistack.org/micro/v3/client"
+	"go.unistack.org/micro/v4/client"
-	"go.unistack.org/micro/v3/config"
+	"go.unistack.org/micro/v4/config"
-	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v4/logger"
-	"go.unistack.org/micro/v3/meter"
+	"go.unistack.org/micro/v4/meter"
-	"go.unistack.org/micro/v3/register"
+	"go.unistack.org/micro/v4/register"
-	"go.unistack.org/micro/v3/router"
+	"go.unistack.org/micro/v4/router"
-	"go.unistack.org/micro/v3/server"
+	"go.unistack.org/micro/v4/server"
-	"go.unistack.org/micro/v3/store"
+	"go.unistack.org/micro/v4/store"
-	"go.unistack.org/micro/v3/tracer"
+	"go.unistack.org/micro/v4/tracer"
-	utildns "go.unistack.org/micro/v3/util/dns"
+	utildns "go.unistack.org/micro/v4/util/dns"
 )
 
 func init() {
@@ -104,7 +104,6 @@ type service struct {
 	done chan struct{}
 	opts Options
 	sync.RWMutex
-	stopped bool
 }
 
 // NewService creates and returns a new Service based on the packages within.
@@ -430,7 +429,7 @@ func (s *service) Stop() error {
 		}
 	}
 
-	s.notifyShutdown()
+	close(s.done)
 
 	return nil
 }
@@ -454,23 +453,10 @@ func (s *service) Run() error {
 		return err
 	}
 
+	// wait on context cancel
 	<-s.done
 
-	return nil
+	return s.Stop()
-}
-
-// notifyShutdown marks the service as stopped and closes the done channel.
-// It ensures the channel is closed only once, preventing multiple closures.
-func (s *service) notifyShutdown() {
-	s.Lock()
-	if s.stopped {
-		s.Unlock()
-		return
-	}
-	s.stopped = true
-	s.Unlock()
-
-	close(s.done)
 }
 
 type Namer interface {