cleanup metadata

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

.github/workflows/job_coverage.yml

@@ -3,6 +3,9 @@ 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
@@ -22,7 +25,7 @@ jobs:
       uses: actions/setup-go@v5
       with:
         cache-dependency-path: "**/*.sum"
-        go-version: 'stable' 
+        go-version: 'stable'
 
     - name: test coverage
       run: |
@@ -39,8 +42,8 @@ jobs:
       name: autocommit
       with:
         commit_message: Apply Code Coverage Badge
-        skip_fetch: true
-        skip_checkout: true
+        skip_fetch: false
+        skip_checkout: false
         file_pattern: ./README.md
 
     - name: push
@@ -48,4 +51,4 @@ jobs:
       uses: ad-m/github-push-action@master
       with:
         github_token: ${{ github.token }}
-        branch: ${{ github.ref }}
+        branch: ${{ github.ref }}

.github/workflows/job_lint.yml

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

.github/workflows/job_sync.yml

@@ -0,0 +1,57 @@
+name: sync
+
+on:
+  schedule:
+    - cron: '*/5 * * * *'
+  push:
+    branches: [ master, v3, v4 ]
+    paths-ignore:
+      - '.github/**'
+      - '.gitea/**'
+  # Allows you to run this workflow manually from the Actions tab
+  workflow_dispatch:
+
+jobs:
+  sync:
+    if: github.server_url != 'https://github.com'
+    runs-on: ubuntu-latest
+    steps:
+    - name: init
+      run: |
+        git config --global user.email "vtolstov <vtolstov@users.noreply.github.com>"
+        git config --global user.name "github-actions[bot]"
+        echo "machine git.unistack.org login vtolstov password ${{ secrets.TOKEN_GITEA }}" >> /root/.netrc
+        echo "machine github.com login vtolstov password ${{ secrets.TOKEN_GITHUB }}" >> /root/.netrc
+
+    - name: sync master
+      run: |
+        git clone --filter=blob:none --filter=tree:0 --branch master --single-branch ${GITHUB_SERVER_URL}/${GITHUB_REPOSITORY} repo
+        cd repo
+        git remote add --no-tags --track master upstream https://github.com/${GITHUB_REPOSITORY}
+        git pull --rebase upstream master
+        git push upstream master --progress
+        git push origin master --progress
+        cd ../
+        rm -rf repo
+
+    - name: sync v3
+      run: |
+        git clone --filter=blob:none --filter=tree:0 --branch v3 --single-branch ${GITHUB_SERVER_URL}/${GITHUB_REPOSITORY} repo
+        cd repo
+        git remote add --no-tags --fetch --track v3 upstream https://github.com/${GITHUB_REPOSITORY}
+        git pull --rebase upstream v3
+        git push upstream v3
+        git push origin v3 --progress
+        cd ../
+        rm -rf repo
+
+    - name: sync v4
+      run: |
+        git clone --filter=blob:none --filter=tree:0 --branch v4 --single-branch ${GITHUB_SERVER_URL}/${GITHUB_REPOSITORY} repo
+        cd repo
+        git remote add --no-tags --fetch --track v4 upstream https://github.com/${GITHUB_REPOSITORY}
+        git pull --rebase upstream v4
+        git push upstream v4
+        git push origin v4 --progress
+        cd ../
+        rm -rf repo

.github/workflows/job_test.yml

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

.github/workflows/job_tests.yml

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

.golangci.yml

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

README.md

@@ -1,9 +1,9 @@
 # Micro
-![Coverage](https://img.shields.io/badge/Coverage-43.9%25-yellow)
+![Coverage](https://img.shields.io/badge/Coverage-45.6%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)
-[![Lint](https://goreportcard.com/badge/go.unistack.org/micro/v3)](https://goreportcard.com/report/go.unistack.org/micro/v3)
+[![Doc](https://img.shields.io/badge/go.dev-reference-007d9c?logo=go&logoColor=white&style=flat-square)](https://pkg.go.dev/go.unistack.org/micro/v4?tab=overview)
+[![Status](https://git.unistack.org/unistack-org/micro/actions/workflows/job_tests.yml/badge.svg?branch=v4)](https://git.unistack.org/unistack-org/micro/actions?query=workflow%3Abuild+branch%3Av4+event%3Apush)
+[![Lint](https://goreportcard.com/badge/go.unistack.org/micro/v4)](https://goreportcard.com/report/go.unistack.org/micro/v4)
 
 Micro is a standard library for microservices.
 

SECURITY.md

@@ -1,15 +0,0 @@
-# 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

@@ -21,7 +21,7 @@ var (
 	// ErrInvalidMessage returns when invalid Message passed
 	ErrInvalidMessage = errors.New("invalid message")
 	// ErrInvalidHandler returns when subscriber passed to Subscribe
-	ErrInvalidHandler = errors.New("invalid handler")
+	ErrInvalidHandler = errors.New("invalid handler, ony func(Message) error and func([]Message) error supported")
 	// DefaultGracefulTimeout
 	DefaultGracefulTimeout = 5 * time.Second
 )

broker/context.go

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

broker/options.go

@@ -79,11 +79,15 @@ type PublishOptions struct {
 	// BodyOnly flag says the message contains raw body bytes and don't need
 	// codec Marshal method
 	BodyOnly bool
+	// Context holds custom options
+	Context context.Context
 }
 
 // NewPublishOptions creates PublishOptions struct
 func NewPublishOptions(opts ...PublishOption) PublishOptions {
-	options := PublishOptions{}
+	options := PublishOptions{
+		Context: context.Background(),
+	}
 	for _, o := range opts {
 		o(&options)
 	}

broker/subscriber.go

@@ -1,87 +1,14 @@
 package broker
 
-import (
-	"fmt"
-	"reflect"
-	"unicode"
-	"unicode/utf8"
-)
-
-const (
-	messageSig  = "func(broker.Message) error"
-	messagesSig = "func([]broker.Message) error"
-)
-
-// Precompute the reflect type for error. Can't use error directly
-// because Typeof takes an empty interface value. This is annoying.
-var typeOfError = reflect.TypeOf((*error)(nil)).Elem()
-
-// Is this an exported - upper case - name?
-func isExported(name string) bool {
-	r, _ := utf8.DecodeRuneInString(name)
-	return unicode.IsUpper(r)
-}
-
-// Is this type exported or a builtin?
-func isExportedOrBuiltinType(t reflect.Type) bool {
-	for t.Kind() == reflect.Ptr {
-		t = t.Elem()
-	}
-	// PkgPath will be non-empty even for an exported type,
-	// so we need to check the type name as well.
-	return isExported(t.Name()) || t.PkgPath() == ""
-}
-
 // IsValidHandler func signature
 func IsValidHandler(sub interface{}) error {
-	typ := reflect.TypeOf(sub)
-	var argType reflect.Type
-	switch typ.Kind() {
-	case reflect.Func:
-		name := "Func"
-		switch typ.NumIn() {
-		case 1:
-			argType = typ.In(0)
-		default:
-			return fmt.Errorf("subscriber %v takes wrong number of args: %v required signature %s", name, typ.NumIn(), messageSig)
-		}
-		if !isExportedOrBuiltinType(argType) {
-			return fmt.Errorf("subscriber %v argument type not exported: %v", name, argType)
-		}
-		if typ.NumOut() != 1 {
-			return fmt.Errorf("subscriber %v has wrong number of return values: %v require signature %s",
-				name, typ.NumOut(), messageSig)
-		}
-		if returnType := typ.Out(0); returnType != typeOfError {
-			return fmt.Errorf("subscriber %v returns %v not error", name, returnType.String())
-		}
+	switch sub.(type) {
 	default:
-		hdlr := reflect.ValueOf(sub)
-		name := reflect.Indirect(hdlr).Type().Name()
-
-		for m := 0; m < typ.NumMethod(); m++ {
-			method := typ.Method(m)
-			switch method.Type.NumIn() {
-			case 3:
-				argType = method.Type.In(2)
-			default:
-				return fmt.Errorf("subscriber %v.%v takes wrong number of args: %v required signature %s",
-					name, method.Name, method.Type.NumIn(), messageSig)
-			}
-
-			if !isExportedOrBuiltinType(argType) {
-				return fmt.Errorf("%v argument type not exported: %v", name, argType)
-			}
-			if method.Type.NumOut() != 1 {
-				return fmt.Errorf(
-					"subscriber %v.%v has wrong number of return values: %v require signature %s",
-					name, method.Name, method.Type.NumOut(), messageSig)
-			}
-			if returnType := method.Type.Out(0); returnType != typeOfError {
-				return fmt.Errorf("subscriber %v.%v returns %v not error", name, method.Name, returnType.String())
-			}
-		}
+		return ErrInvalidHandler
+	case func(Message) error:
+		break
+	case func([]Message) error:
+		break
 	}
-
 	return nil
 }

go.mod

@@ -8,10 +8,11 @@ require (
 	github.com/KimMachineGun/automemlimit v0.7.0
 	github.com/ash3in/uuidv8 v1.2.0
 	github.com/google/uuid v1.6.0
-	github.com/heimdalr/dag v1.5.0
 	github.com/matoous/go-nanoid v1.5.1
 	github.com/patrickmn/go-cache v2.1.0+incompatible
 	github.com/silas/dag v0.0.0-20220518035006-a7e85ada93c5
+	github.com/spf13/cast v1.7.1
+	github.com/stretchr/testify v1.10.0
 	go.uber.org/atomic v1.11.0
 	go.uber.org/automaxprocs v1.6.0
 	go.unistack.org/micro-proto/v4 v4.1.0
@@ -23,12 +24,9 @@ require (
 
 require (
 	github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc // indirect
-	github.com/emirpasic/gods v1.18.1 // indirect
-	github.com/kr/pretty v0.3.1 // indirect
 	github.com/pbnjay/memory v0.0.0-20210728143218-7b4eea64cf58 // indirect
 	github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2 // indirect
 	github.com/rogpeppe/go-internal v1.13.1 // indirect
-	github.com/stretchr/testify v1.10.0 // indirect
 	golang.org/x/net v0.34.0 // indirect
 	golang.org/x/sys v0.29.0 // indirect
 	google.golang.org/genproto/googleapis/rpc v0.0.0-20241216192217-9240e9c98484 // indirect

go.sum

@@ -6,22 +6,16 @@ github.com/KimMachineGun/automemlimit v0.7.0 h1:7G06p/dMSf7G8E6oq+f2uOPuVncFyIlD
 github.com/KimMachineGun/automemlimit v0.7.0/go.mod h1:QZxpHaGOQoYvFhv/r4u3U0JTC2ZcOwbSr11UZF46UBM=
 github.com/ash3in/uuidv8 v1.2.0 h1:2oogGdtCPwaVtyvPPGin4TfZLtOGE5F+W++E880G6SI=
 github.com/ash3in/uuidv8 v1.2.0/go.mod h1:BnU0wJBxnzdEKmVg4xckBkD+VZuecTFTUP3M0dWgyY4=
-github.com/creack/pty v1.1.9/go.mod h1:oKZEueFk5CKHvIhNR5MUki03XCEU+Q6VDXinZuGJ33E=
 github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc h1:U9qPSI2PIWSS1VwoXQT9A3Wy9MM3WgvqSxFWenqJduM=
 github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
-github.com/emirpasic/gods v1.18.1 h1:FXtiHYKDGKCW2KzwZKx0iC0PQmdlorYgdFG9jPXJ1Bc=
-github.com/emirpasic/gods v1.18.1/go.mod h1:8tpGGwCnJ5H4r6BWwaV6OrWmMoPhUl5jm/FMNAnJvWQ=
-github.com/go-test/deep v1.1.0 h1:WOcxcdHcvdgThNXjw0t76K42FXTU7HpNQWHpA2HHNlg=
-github.com/go-test/deep v1.1.0/go.mod h1:5C2ZWiW0ErCdrYzpqxLbTX7MG14M9iiw8DgHncVwcsE=
+github.com/frankban/quicktest v1.14.6 h1:7Xjx+VpznH+oBnejlPUj8oUpdxnVs4f8XU8WnHkI4W8=
+github.com/frankban/quicktest v1.14.6/go.mod h1:4ptaffx2x8+WTWXmUCuVU6aPUX1/Mz7zb5vbUoiM6w0=
 github.com/golang/protobuf v1.5.4 h1:i7eJL8qZTpSEXOPTxNKhASYpMn+8e5Q6AdndVa1dWek=
 github.com/golang/protobuf v1.5.4/go.mod h1:lnTiLA8Wa4RWRcIUkrtSVa5nRhsEGBg48fD6rSs7xps=
 github.com/google/go-cmp v0.6.0 h1:ofyhxvXcZhMsU5ulbFiLKl/XBFqE1GSq7atu8tAmTRI=
 github.com/google/go-cmp v0.6.0/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
-github.com/google/uuid v1.3.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
 github.com/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
 github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
-github.com/heimdalr/dag v1.5.0 h1:hqVtijvY776P5OKP3QbdVBRt3Xxq6BYopz3XgklsGvo=
-github.com/heimdalr/dag v1.5.0/go.mod h1:lthekrHl01dddmzqyBQ1YZbi7XcVGGzjFo0jIky5knc=
 github.com/kisielk/sqlstruct v0.0.0-20201105191214-5f3e10d3ab46/go.mod h1:yyMNCyc/Ib3bDTKd379tNMpB/7/H5TjM2Y9QJ5THLbE=
 github.com/kr/pretty v0.2.1/go.mod h1:ipq/a2n7PKx3OHsz4KJII5eveXtPO4qwEXGdVfWzfnI=
 github.com/kr/pretty v0.3.1 h1:flRD4NNwYAUpkphVc1HcthR4KEIFJ65n8Mw5qdRn3LE=
@@ -36,16 +30,16 @@ github.com/patrickmn/go-cache v2.1.0+incompatible h1:HRMgzkcYKYpi3C8ajMPV8OFXaaR
 github.com/patrickmn/go-cache v2.1.0+incompatible/go.mod h1:3Qf8kWWT7OJRJbdiICTKqZju1ZixQ/KpMGzzAfe6+WQ=
 github.com/pbnjay/memory v0.0.0-20210728143218-7b4eea64cf58 h1:onHthvaw9LFnH4t2DcNVpwGmV9E1BkGknEliJkfwQj0=
 github.com/pbnjay/memory v0.0.0-20210728143218-7b4eea64cf58/go.mod h1:DXv8WO4yhMYhSNPKjeNKa5WY9YCIEBRbNzFFPJbWO6Y=
-github.com/pkg/diff v0.0.0-20210226163009-20ebb0f2a09e/go.mod h1:pJLUxLENpZxwdsKMEsNbx1VGcRFpLqf3715MtcvvzbA=
 github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2 h1:Jamvg5psRIccs7FGNTlIRMkT8wgtp5eCXdBlqhYGL6U=
 github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/prashantv/gostub v1.1.0 h1:BTyx3RfQjRHnUWaGF9oQos79AlQ5k8WNktv7VGvVH4g=
 github.com/prashantv/gostub v1.1.0/go.mod h1:A5zLQHz7ieHGG7is6LLXLz7I8+3LZzsrV0P1IAHhP5U=
-github.com/rogpeppe/go-internal v1.9.0/go.mod h1:WtVeX8xhTBvf0smdhujwtBcq4Qrzq/fJaraNFVN+nFs=
 github.com/rogpeppe/go-internal v1.13.1 h1:KvO1DLK/DRN07sQ1LQKScxyZJuNnedQ5/wKSR38lUII=
 github.com/rogpeppe/go-internal v1.13.1/go.mod h1:uMEvuHeurkdAXX61udpOXGD/AzZDWNMNyH2VO9fmH0o=
 github.com/silas/dag v0.0.0-20220518035006-a7e85ada93c5 h1:G/FZtUu7a6NTWl3KUHMV9jkLAh/Rvtf03NWMHaEDl+E=
 github.com/silas/dag v0.0.0-20220518035006-a7e85ada93c5/go.mod h1:7RTUFBdIRC9nZ7/3RyRNH1bdqIShrDejd1YbLwgPS+I=
+github.com/spf13/cast v1.7.1 h1:cuNEagBQEHWN1FnbGEjCXL2szYEXqfJPbP2HNUaca9Y=
+github.com/spf13/cast v1.7.1/go.mod h1:ancEpBxwJDODSW/UG4rDrAqiKolqNNh2DX3mk86cAdo=
 github.com/stretchr/testify v1.10.0 h1:Xv5erBjTwe/5IxqUQTdXv5kgmIvbHo3QQyRwhJsOfJA=
 github.com/stretchr/testify v1.10.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=
 go.uber.org/atomic v1.11.0 h1:ZvwS0R+56ePWxUNi+Atn9dWONBPp/AUETXlHW0DxSjE=

hooks/metadata/metadata.go

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

hooks/recovery/recovery.go

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

hooks/requestid/requestid.go

@@ -0,0 +1,112 @@
+package requestid
+
+import (
+	"context"
+	"net/textproto"
+
+	"go.unistack.org/micro/v4/client"
+	"go.unistack.org/micro/v4/metadata"
+	"go.unistack.org/micro/v4/server"
+	"go.unistack.org/micro/v4/util/id"
+)
+
+type XRequestIDKey struct{}
+
+// DefaultMetadataKey contains metadata key
+var DefaultMetadataKey = textproto.CanonicalMIMEHeaderKey("x-request-id")
+
+// DefaultMetadataFunc wil be used if user not provide own func to fill metadata
+var DefaultMetadataFunc = func(ctx context.Context) (context.Context, error) {
+	var xid string
+
+	cid, cok := ctx.Value(XRequestIDKey{}).(string)
+	if cok && cid != "" {
+		xid = cid
+	}
+
+	imd, iok := metadata.FromIncomingContext(ctx)
+	if !iok || imd == nil {
+		imd = metadata.New(1)
+		ctx = metadata.NewIncomingContext(ctx, imd)
+	}
+
+	omd, ook := metadata.FromOutgoingContext(ctx)
+	if !ook || omd == nil {
+		omd = metadata.New(1)
+		ctx = metadata.NewOutgoingContext(ctx, omd)
+	}
+
+	if xid == "" {
+		var ids []string
+
+		for i := range imd.Get(DefaultMetadataKey) {
+			if ids[i] != "" {
+				xid = ids[i]
+			}
+		}
+
+		for i := range omd.Get(DefaultMetadataKey) {
+			if ids[i] != "" {
+				xid = ids[i]
+			}
+		}
+	}
+
+	if xid == "" {
+		var err error
+		xid, err = id.New()
+		if err != nil {
+			return ctx, err
+		}
+	}
+
+	if !cok {
+		ctx = context.WithValue(ctx, XRequestIDKey{}, xid)
+	}
+
+	if !iok {
+		imd.Set(DefaultMetadataKey, xid)
+	}
+
+	if !ook {
+		omd.Set(DefaultMetadataKey, xid)
+	}
+
+	return ctx, nil
+}
+
+type hook struct{}
+
+func NewHook() *hook {
+	return &hook{}
+}
+
+func (w *hook) ServerHandler(next server.FuncHandler) server.FuncHandler {
+	return func(ctx context.Context, req server.Request, rsp interface{}) error {
+		var err error
+		if ctx, err = DefaultMetadataFunc(ctx); err != nil {
+			return err
+		}
+		return next(ctx, req, rsp)
+	}
+}
+
+func (w *hook) ClientCall(next client.FuncCall) client.FuncCall {
+	return func(ctx context.Context, req client.Request, rsp interface{}, opts ...client.CallOption) error {
+		var err error
+		if ctx, err = DefaultMetadataFunc(ctx); err != nil {
+			return err
+		}
+		return next(ctx, req, rsp, opts...)
+	}
+}
+
+func (w *hook) ClientStream(next client.FuncStream) client.FuncStream {
+	return func(ctx context.Context, req client.Request, opts ...client.CallOption) (client.Stream, error) {
+		var err error
+		if ctx, err = DefaultMetadataFunc(ctx); err != nil {
+			return nil, err
+		}
+		return next(ctx, req, opts...)
+	}
+}

hooks/requestid/requestid_test.go

@@ -0,0 +1,34 @@
+package requestid
+
+import (
+	"context"
+	"slices"
+	"testing"
+
+	"go.unistack.org/micro/v4/metadata"
+)
+
+func TestDefaultMetadataFunc(t *testing.T) {
+	ctx := context.TODO()
+
+	nctx, err := DefaultMetadataFunc(ctx)
+	if err != nil {
+		t.Fatalf("%v", err)
+	}
+
+	imd, ok := metadata.FromIncomingContext(nctx)
+	if !ok {
+		t.Fatalf("md missing in incoming context")
+	}
+	omd, ok := metadata.FromOutgoingContext(nctx)
+	if !ok {
+		t.Fatalf("md missing in outgoing context")
+	}
+
+	iv := imd.Get(DefaultMetadataKey)
+	ov := omd.Get(DefaultMetadataKey)
+
+	if !slices.Equal(iv, ov) {
+		t.Fatalf("missing metadata key value %v != %v", iv, ov)
+	}
+}

hooks/validator/validator.go

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

logger/options.go

@@ -99,6 +99,7 @@ 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_test.go

@@ -124,7 +124,7 @@ func TestWithDedupKeysWithAddFields(t *testing.T) {
 
 	l.Info(ctx, "msg3")
 
-	if !bytes.Contains(buf.Bytes(), []byte(`msg=msg3 key1=val1 key2=val2`)) {
+	if !bytes.Contains(buf.Bytes(), []byte(`msg=msg3 key1=val4 key2=val3`)) {
 		t.Fatalf("logger error not works, buf contains: %s", buf.Bytes())
 	}
 }
@@ -406,7 +406,7 @@ func TestLogger(t *testing.T) {
 func Test_WithContextAttrFunc(t *testing.T) {
 	loggerContextAttrFuncs := []logger.ContextAttrFunc{
 		func(ctx context.Context) []interface{} {
-			md, ok := metadata.FromIncomingContext(ctx)
+			md, ok := metadata.FromOutgoingContext(ctx)
 			if !ok {
 				return nil
 			}
@@ -425,7 +425,7 @@ func Test_WithContextAttrFunc(t *testing.T) {
 	logger.DefaultContextAttrFuncs = append(logger.DefaultContextAttrFuncs, loggerContextAttrFuncs...)
 
 	ctx := context.TODO()
-	ctx = metadata.AppendIncomingContext(ctx, "X-Request-Id", uuid.New().String(),
+	ctx = metadata.AppendOutgoingContext(ctx, "X-Request-Id", uuid.New().String(),
 		"Source-Service", "Test-System")
 
 	buf := bytes.NewBuffer(nil)
@@ -445,9 +445,9 @@ func Test_WithContextAttrFunc(t *testing.T) {
 		t.Fatalf("logger info, buf %s", buf.Bytes())
 	}
 	buf.Reset()
-	imd, _ := metadata.FromIncomingContext(ctx)
+	omd, _ := metadata.FromOutgoingContext(ctx)
 	l.Info(ctx, "test message1")
-	imd.Set("Source-Service", "Test-System2")
+	omd.Set("Source-Service", "Test-System2")
 	l.Info(ctx, "test message2")
 
 	// t.Logf("xxx %s", buf.Bytes())

metadata/metadata.go

@@ -69,6 +69,15 @@ func (md Metadata) Copy() Metadata {
 	return out
 }
 
+// AsMap returns a copy of Metadata with map[string]string.
+func (md Metadata) AsMap() map[string]string {
+	out := make(map[string]string, len(md))
+	for k, v := range md {
+		out[k] = strings.Join(v, ",")
+	}
+	return out
+}
+
 // AsHTTP1 returns a copy of Metadata
 // with CanonicalMIMEHeaderKey.
 func (md Metadata) AsHTTP1() map[string][]string {
@@ -97,16 +106,7 @@ func (md Metadata) CopyTo(out Metadata) {
 }
 
 // Get obtains the values for a given key.
-func (md Metadata) MustGet(k string) []string {
-	v, ok := md.Get(k)
-	if !ok {
-		panic("missing metadata key")
-	}
-	return v
-}
-
-// Get obtains the values for a given key.
-func (md Metadata) Get(k string) ([]string, bool) {
+func (md Metadata) Get(k string) []string {
 	v, ok := md[k]
 	if !ok {
 		v, ok = md[strings.ToLower(k)]
@@ -114,27 +114,13 @@ func (md Metadata) Get(k string) ([]string, bool) {
 	if !ok {
 		v, ok = md[textproto.CanonicalMIMEHeaderKey(k)]
 	}
-	return v, ok
-}
-
-// MustGetJoined obtains the values for a given key
-// with joined values with "," symbol
-func (md Metadata) MustGetJoined(k string) string {
-	v, ok := md.GetJoined(k)
-	if !ok {
-		panic("missing metadata key")
-	}
 	return v
 }
 
 // GetJoined obtains the values for a given key
 // with joined values with "," symbol
-func (md Metadata) GetJoined(k string) (string, bool) {
-	v, ok := md.Get(k)
-	if !ok {
-		return "", ok
-	}
-	return strings.Join(v, ","), true
+func (md Metadata) GetJoined(k string) string {
+	return strings.Join(md.Get(k), ",")
 }
 
 // Set sets the value of a given key with a slice of values.
@@ -232,24 +218,6 @@ func AppendContext(ctx context.Context, kv ...string) context.Context {
 	return context.WithValue(ctx, metadataCurrentKey{}, rawMetadata{md: md.md, added: added})
 }
 
-// AppendIncomingContext returns a new context with the provided kv merged
-// with any existing metadata in the context. Please refer to the documentation
-// of Pairs for a description of kv.
-func AppendIncomingContext(ctx context.Context, kv ...string) context.Context {
-	if len(kv)%2 == 1 {
-		panic(fmt.Sprintf("metadata: AppendIncomingContext got an odd number of input pairs for metadata: %d", len(kv)))
-	}
-	md, _ := ctx.Value(metadataIncomingKey{}).(rawMetadata)
-	added := make([][]string, len(md.added)+1)
-	copy(added, md.added)
-	kvCopy := make([]string, 0, len(kv))
-	for i := 0; i < len(kv); i += 2 {
-		kvCopy = append(kvCopy, strings.ToLower(kv[i]), kv[i+1])
-	}
-	added[len(added)-1] = kvCopy
-	return context.WithValue(ctx, metadataIncomingKey{}, rawMetadata{md: md.md, added: added})
-}
-
 // AppendOutgoingContext returns a new context with the provided kv merged
 // with any existing metadata in the context. Please refer to the documentation
 // of Pairs for a description of kv.

metadata/metadata_test.go

@@ -19,8 +19,8 @@ func TestAppendOutgoingContextModify(t *testing.T) {
 func TestLowercase(t *testing.T) {
 	md := New(1)
 	md["x-request-id"] = []string{"12345"}
-	v, ok := md.GetJoined("X-Request-Id")
-	if !ok || v == "" {
+	v := md.GetJoined("X-Request-Id")
+	if v == "" {
 		t.Fatalf("metadata invalid %#+v", md)
 	}
 }
@@ -51,29 +51,17 @@ func TestMetadataSetMultiple(t *testing.T) {
 	md := New(4)
 	md.Set("key1", "val1", "key2", "val2")
 
-	if v, ok := md.GetJoined("key1"); !ok || v != "val1" {
+	if v := md.GetJoined("key1"); v != "val1" {
 		t.Fatalf("invalid kv %#+v", md)
 	}
-	if v, ok := md.GetJoined("key2"); !ok || v != "val2" {
+	if v := md.GetJoined("key2"); v != "val2" {
 		t.Fatalf("invalid kv %#+v", md)
 	}
 }
 
-func TestAppend(t *testing.T) {
-	ctx := context.Background()
-	ctx = AppendIncomingContext(ctx, "key1", "val1", "key2", "val2")
-	md, ok := FromIncomingContext(ctx)
-	if !ok {
-		t.Fatal("metadata empty")
-	}
-	if _, ok := md.Get("key1"); !ok {
-		t.Fatal("key1 not found")
-	}
-}
-
 func TestPairs(t *testing.T) {
 	md := Pairs("key1", "val1", "key2", "val2")
-	if _, ok := md.Get("key1"); !ok {
+	if v := md.Get("key1"); v == nil {
 		t.Fatal("key1 not found")
 	}
 }
@@ -97,7 +85,7 @@ func TestPassing(t *testing.T) {
 	if !ok {
 		t.Fatalf("missing metadata from outgoing context")
 	}
-	if v, ok := md.Get("Key1"); !ok || v[0] != "Val1" {
+	if v := md.Get("Key1"); v == nil || v[0] != "Val1" {
 		t.Fatalf("invalid metadata value %#+v", md)
 	}
 }
@@ -127,21 +115,21 @@ func TestIterator(t *testing.T) {
 func TestMedataCanonicalKey(t *testing.T) {
 	md := New(1)
 	md.Set("x-request-id", "12345")
-	v, ok := md.GetJoined("x-request-id")
-	if !ok {
+	v := md.GetJoined("x-request-id")
+	if v == "" {
 		t.Fatalf("failed to get x-request-id")
 	} else if v != "12345" {
 		t.Fatalf("invalid metadata value: %s != %s", "12345", v)
 	}
 
-	v, ok = md.GetJoined("X-Request-Id")
-	if !ok {
+	v = md.GetJoined("X-Request-Id")
+	if v == "" {
 		t.Fatalf("failed to get x-request-id")
 	} else if v != "12345" {
 		t.Fatalf("invalid metadata value: %s != %s", "12345", v)
 	}
-	v, ok = md.GetJoined("X-Request-ID")
-	if !ok {
+	v = md.GetJoined("X-Request-ID")
+	if v == "" {
 		t.Fatalf("failed to get x-request-id")
 	} else if v != "12345" {
 		t.Fatalf("invalid metadata value: %s != %s", "12345", v)
@@ -153,8 +141,8 @@ func TestMetadataSet(t *testing.T) {
 
 	md.Set("Key", "val")
 
-	val, ok := md.GetJoined("Key")
-	if !ok {
+	val := md.GetJoined("Key")
+	if val == "" {
 		t.Fatal("key Key not found")
 	}
 	if val != "val" {
@@ -169,8 +157,8 @@ func TestMetadataDelete(t *testing.T) {
 	}
 
 	md.Del("Baz")
-	_, ok := md.Get("Baz")
-	if ok {
+	v := md.Get("Baz")
+	if v != nil {
 		t.Fatal("key Baz not deleted")
 	}
 }
@@ -269,20 +257,6 @@ func TestNewOutgoingContext(t *testing.T) {
 	}
 }
 
-func TestAppendIncomingContext(t *testing.T) {
-	md := New(1)
-	md.Set("key1", "val1")
-	ctx := AppendIncomingContext(context.TODO(), "key2", "val2")
-
-	nmd, ok := FromIncomingContext(ctx)
-	if nmd == nil || !ok {
-		t.Fatal("AppendIncomingContext not works")
-	}
-	if v, ok := nmd.GetJoined("key2"); !ok || v != "val2" {
-		t.Fatal("AppendIncomingContext not works")
-	}
-}
-
 func TestAppendOutgoingContext(t *testing.T) {
 	md := New(1)
 	md.Set("key1", "val1")
@@ -292,7 +266,7 @@ func TestAppendOutgoingContext(t *testing.T) {
 	if nmd == nil || !ok {
 		t.Fatal("AppendOutgoingContext not works")
 	}
-	if v, ok := nmd.GetJoined("key2"); !ok || v != "val2" {
+	if v := nmd.GetJoined("key2"); v != "val2" {
 		t.Fatal("AppendOutgoingContext not works")
 	}
 }

options/options.go

@@ -6,7 +6,7 @@ import (
 	"time"
 
 	"github.com/spf13/cast"
-	mreflect "go.unistack.org/micro/v3/util/reflect"
+	mreflect "go.unistack.org/micro/v4/util/reflect"
 )
 
 // Options interface must be used by all options

service.go

@@ -99,6 +99,7 @@ type service struct {
 	done chan struct{}
 	opts Options
 	sync.RWMutex
+	stopped bool
 }
 
 // NewService creates and returns a new Service based on the packages within.
@@ -424,7 +425,7 @@ func (s *service) Stop() error {
 		}
 	}
 
-	close(s.done)
+	s.notifyShutdown()
 
 	return nil
 }
@@ -448,10 +449,23 @@ func (s *service) Run() error {
 		return err
 	}
 
-	// wait on context cancel
 	<-s.done
 
-	return s.Stop()
+	return nil
+}
+
+// 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 {

service_test.go

@@ -3,7 +3,9 @@ package micro
 import (
 	"reflect"
 	"testing"
+	"time"
 
+	"github.com/stretchr/testify/require"
 	"go.unistack.org/micro/v4/broker"
 	"go.unistack.org/micro/v4/client"
 	"go.unistack.org/micro/v4/config"
@@ -737,3 +739,41 @@ func Test_getNameIndex(t *testing.T) {
 	}
 }
 */
+
+func TestServiceShutdown(t *testing.T) {
+	defer func() {
+		if r := recover(); r != nil {
+			t.Fatalf("service shutdown failed: %v", r)
+		}
+	}()
+
+	s, ok := NewService().(*service)
+	require.NotNil(t, s)
+	require.True(t, ok)
+
+	require.NoError(t, s.Start())
+	require.False(t, s.stopped)
+
+	require.NoError(t, s.Stop())
+	require.True(t, s.stopped)
+}
+
+func TestServiceMultipleShutdowns(t *testing.T) {
+	defer func() {
+		if r := recover(); r != nil {
+			t.Fatalf("service shutdown failed: %v", r)
+		}
+	}()
+
+	s := NewService()
+
+	go func() {
+		time.Sleep(10 * time.Millisecond)
+		// first call
+		require.NoError(t, s.Stop())
+		// duplicate call
+		require.NoError(t, s.Stop())
+	}()
+
+	require.NoError(t, s.Run())
+}

tracer/memory/memory.go

@@ -89,6 +89,10 @@ func (s *Span) Tracer() tracer.Tracer {
 	return s.tracer
 }
 
+func (s *Span) IsRecording() bool {
+	return true
+}
+
 type Event struct {
 	name   string
 	labels []interface{}

tracer/noop.go

@@ -120,6 +120,10 @@ func (s *noopSpan) SetStatus(st SpanStatus, msg string) {
 	s.statusMsg = msg
 }
 
+func (s *noopSpan) IsRecording() bool {
+	return false
+}
+
 // NewTracer returns new memory tracer
 func NewTracer(opts ...Option) Tracer {
 	return &noopTracer{

tracer/tracer.go

@@ -78,4 +78,6 @@ type Span interface {
 	TraceID() string
 	// SpanID returns span id
 	SpanID() string
+	// IsRecording returns the recording state of the Span.
+	IsRecording() bool
 }

util/reflect/struct.go

@@ -489,35 +489,74 @@ func URLMap(query string) (map[string]interface{}, error) {
 	return mp.(map[string]interface{}), nil
 }
 
-// FlattenMap expand key.subkey to nested map
-func FlattenMap(a map[string]interface{}) map[string]interface{} {
-	// preprocess map
-	nb := make(map[string]interface{}, len(a))
-	for k, v := range a {
-		ps := strings.Split(k, ".")
-		if len(ps) == 1 {
-			nb[k] = v
+// FlattenMap flattens a nested map into a single-level map using dot notation for nested keys.
+// In case of key conflicts, all nested levels will be discarded in favor of the first-level key.
+//
+// Example #1:
+//
+//	Input:
+//	  {
+//	    "user.name": "alex",
+//	    "user.document.id": "document_id"
+//	    "user.document.number": "document_number"
+//	  }
+//	Output:
+//	  {
+//	    "user": {
+//	      "name": "alex",
+//	      "document": {
+//	        "id": "document_id"
+//	        "number": "document_number"
+//	      }
+//	    }
+//	  }
+//
+// Example #2 (with conflicts):
+//
+//	Input:
+//	  {
+//	    "user": "alex",
+//	    "user.document.id": "document_id"
+//	    "user.document.number": "document_number"
+//	  }
+//	Output:
+//	  {
+//	    "user": "alex"
+//	  }
+func FlattenMap(input map[string]interface{}) map[string]interface{} {
+	result := make(map[string]interface{})
+
+	for k, v := range input {
+		parts := strings.Split(k, ".")
+
+		if len(parts) == 1 {
+			result[k] = v
 			continue
 		}
-		em := make(map[string]interface{})
-		em[ps[len(ps)-1]] = v
-		for i := len(ps) - 2; i > 0; i-- {
-			nm := make(map[string]interface{})
-			nm[ps[i]] = em
-			em = nm
-		}
-		if vm, ok := nb[ps[0]]; ok {
-			// nested map
-			nm := vm.(map[string]interface{})
-			for vk, vv := range em {
-				nm[vk] = vv
+
+		current := result
+
+		for i, part := range parts {
+			// last element in the path
+			if i == len(parts)-1 {
+				current[part] = v
+				break
+			}
+
+			// initialize map for current level if not exist
+			if _, ok := current[part]; !ok {
+				current[part] = make(map[string]interface{})
+			}
+
+			if nested, ok := current[part].(map[string]interface{}); ok {
+				current = nested // continue to the nested map
+			} else {
+				break // if current element is not a map, ignore it
 			}
-			nb[ps[0]] = nm
-		} else {
-			nb[ps[0]] = em
 		}
 	}
-	return nb
+
+	return result
 }
 
 /*

util/reflect/struct_test.go

@@ -6,6 +6,7 @@ import (
 	"testing"
 	"time"
 
+	"github.com/stretchr/testify/require"
 	rutil "go.unistack.org/micro/v4/util/reflect"
 )
 
@@ -319,3 +320,140 @@ func TestIsZero(t *testing.T) {
 
 	// t.Logf("XX %#+v\n", ok)
 }
+
+func TestFlattenMap(t *testing.T) {
+	tests := []struct {
+		name     string
+		input    map[string]interface{}
+		expected map[string]interface{}
+	}{
+		{
+			name:     "empty map",
+			input:    map[string]interface{}{},
+			expected: map[string]interface{}{},
+		},
+		{
+			name:     "nil map",
+			input:    nil,
+			expected: map[string]interface{}{},
+		},
+		{
+			name: "single level",
+			input: map[string]interface{}{
+				"username": "username",
+				"password": "password",
+			},
+			expected: map[string]interface{}{
+				"username": "username",
+				"password": "password",
+			},
+		},
+		{
+			name: "two level",
+			input: map[string]interface{}{
+				"order_id":      "order_id",
+				"user.name":     "username",
+				"user.password": "password",
+			},
+			expected: map[string]interface{}{
+				"order_id": "order_id",
+				"user": map[string]interface{}{
+					"name":     "username",
+					"password": "password",
+				},
+			},
+		},
+		{
+			name: "three level",
+			input: map[string]interface{}{
+				"order_id":             "order_id",
+				"user.name":            "username",
+				"user.password":        "password",
+				"user.document.id":     "document_id",
+				"user.document.number": "document_number",
+			},
+			expected: map[string]interface{}{
+				"order_id": "order_id",
+				"user": map[string]interface{}{
+					"name":     "username",
+					"password": "password",
+					"document": map[string]interface{}{
+						"id":     "document_id",
+						"number": "document_number",
+					},
+				},
+			},
+		},
+		{
+			name: "four level",
+			input: map[string]interface{}{
+				"order_id":                    "order_id",
+				"user.name":                   "username",
+				"user.password":               "password",
+				"user.document.id":            "document_id",
+				"user.document.number":        "document_number",
+				"user.info.permissions.read":  "available",
+				"user.info.permissions.write": "available",
+			},
+			expected: map[string]interface{}{
+				"order_id": "order_id",
+				"user": map[string]interface{}{
+					"name":     "username",
+					"password": "password",
+					"document": map[string]interface{}{
+						"id":     "document_id",
+						"number": "document_number",
+					},
+					"info": map[string]interface{}{
+						"permissions": map[string]interface{}{
+							"read":  "available",
+							"write": "available",
+						},
+					},
+				},
+			},
+		},
+		{
+			name: "key conflicts",
+			input: map[string]interface{}{
+				"user":          "user",
+				"user.name":     "username",
+				"user.password": "password",
+			},
+			expected: map[string]interface{}{
+				"user": "user",
+			},
+		},
+		{
+			name: "overwriting conflicts",
+			input: map[string]interface{}{
+				"order_id":             "order_id",
+				"user.document.id":     "document_id",
+				"user.document.number": "document_number",
+				"user.info.address":    "address",
+				"user.info.phone":      "phone",
+			},
+			expected: map[string]interface{}{
+				"order_id": "order_id",
+				"user": map[string]interface{}{
+					"document": map[string]interface{}{
+						"id":     "document_id",
+						"number": "document_number",
+					},
+					"info": map[string]interface{}{
+						"address": "address",
+						"phone":   "phone",
+					},
+				},
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			for range 100 { // need to exclude the impact of key order in the map on the test.
+				require.Equal(t, tt.expected, rutil.FlattenMap(tt.input))
+			}
+		})
+	}
+}