logger fixup

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

.gitea/workflows/lint.yml

@@ -1,24 +0,0 @@
-name: lint
-on:
-  pull_request:
-    branches:
-    - master
-    - v3
-jobs:
-  lint:
-    name: lint
-    runs-on: ubuntu-latest
-    steps:
-    - name: setup-go
-      uses: actions/setup-go@v3
-      with:
-        go-version: 1.21
-    - name: checkout
-      uses: actions/checkout@v3
-    - name: deps
-      run: go get -v -d ./...
-    - name: lint
-      uses: https://github.com/golangci/golangci-lint-action@v3.4.0
-      continue-on-error: true
-      with:
-        version: v1.52

.gitea/workflows/pr.yml

@@ -1,23 +0,0 @@
-name: pr
-on:
-  pull_request:
-    branches:
-    - master
-    - v3
-jobs:
-  test:
-    name: test
-    runs-on: ubuntu-latest
-    steps:
-    - name: checkout
-      uses: actions/checkout@v3
-    - name: setup-go
-      uses: actions/setup-go@v3
-      with:
-        go-version: 1.21
-    - name: deps
-      run: go get -v -t -d ./...
-    - name: test
-      env:
-        INTEGRATION_TESTS: yes
-      run: go test -mod readonly -v ./...

.github/workflows/job_coverage.yml

@@ -0,0 +1,53 @@
+name: coverage
+
+on:
+  push:
+    branches: [ main, v3, v4 ]
+    paths-ignore:
+      - '.github/**'
+      - '.gitea/**'
+  pull_request:
+    branches: [ main, v3, v4 ]
+
+jobs:
+
+  build:
+    if: github.server_url != 'https://github.com'
+    runs-on: ubuntu-latest
+    steps:
+    - name: checkout code
+      uses: actions/checkout@v4
+      with:
+        filter: 'blob:none'
+
+    - name: setup go
+      uses: actions/setup-go@v5
+      with:
+        cache-dependency-path: "**/*.sum"
+        go-version: 'stable'
+
+    - name: test coverage
+      run: |
+        go test -v -cover ./... -covermode=count -coverprofile coverage.out -coverpkg ./...
+        go tool cover -func coverage.out -o coverage.out
+
+    - name: coverage badge
+      uses: tj-actions/coverage-badge-go@v2
+      with:
+        green: 80
+        filename: coverage.out
+
+    - uses: stefanzweifel/git-auto-commit-action@v4
+      name: autocommit
+      with:
+        commit_message: Apply Code Coverage Badge
+        skip_fetch: false
+        skip_checkout: false
+        file_pattern: ./README.md
+
+    - name: push
+      if: steps.auto-commit-action.outputs.changes_detected == 'true'
+      uses: ad-m/github-push-action@master
+      with:
+        github_token: ${{ github.token }}
+        branch: ${{ github.ref }}

.github/workflows/job_lint.yml

@@ -0,0 +1,29 @@
+name: lint
+
+on:
+  pull_request:
+    types: [opened, reopened, synchronize]
+    branches: [ master, v3, v4 ]
+    paths-ignore:
+      - '.github/**'
+      - '.gitea/**'
+
+jobs:
+  lint:
+    runs-on: ubuntu-latest
+    steps:
+    - name: checkout code
+      uses: actions/checkout@v4
+      with:
+        filter: 'blob:none'
+    - name: setup go
+      uses: actions/setup-go@v5
+      with:
+        cache-dependency-path: "**/*.sum"
+        go-version: 'stable'
+    - name: setup deps
+      run: go get -v ./...
+    - name: run lint
+      uses: golangci/golangci-lint-action@v6
+      with:
+        version: 'latest'

.github/workflows/job_test.yml

@@ -0,0 +1,31 @@
+name: test
+
+on:
+  pull_request:
+    types: [opened, reopened, synchronize]
+    branches: [ master, v3, v4 ]
+  push:
+    branches: [ master, v3, v4 ]
+    paths-ignore:
+      - '.github/**'
+      - '.gitea/**'
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    steps:
+    - name: checkout code
+      uses: actions/checkout@v4
+      with:
+        filter: 'blob:none'
+    - name: setup go
+      uses: actions/setup-go@v5
+      with:
+        cache-dependency-path: "**/*.sum"
+        go-version: 'stable'
+    - name: setup deps
+      run: go get -v ./...
+    - name: run test
+      env:
+        INTEGRATION_TESTS: yes
+      run: go test -mod readonly -v ./...

.github/workflows/job_tests.yml

@@ -0,0 +1,50 @@
+name: test
+
+on:
+  pull_request:
+    types: [opened, reopened, synchronize]
+    branches: [ master, v3, v4 ]
+  push:
+    branches: [ master, v3, v4 ]
+    paths-ignore:
+      - '.github/**'
+      - '.gitea/**'
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    steps:
+    - name: checkout code
+      uses: actions/checkout@v4
+      with:
+        filter: 'blob:none'
+    - name: checkout tests
+      uses: actions/checkout@v4
+      with:
+        ref: master
+        filter: 'blob:none'
+        repository: unistack-org/micro-tests
+        path: micro-tests
+    - name: setup go
+      uses: actions/setup-go@v5
+      with:
+        cache-dependency-path: "**/*.sum"
+        go-version: 'stable'
+    - name: setup go work
+      env:
+        GOWORK: ${{ github.workspace }}/go.work
+      run: |
+        go work init
+        go work use .
+        go work use micro-tests
+    - name: setup deps
+      env:
+        GOWORK: ${{ github.workspace }}/go.work
+      run: go get -v ./...
+    - name: run tests
+      env:
+        INTEGRATION_TESTS: yes
+        GOWORK: ${{ github.workspace }}/go.work
+      run: |
+        cd micro-tests
+        go test -mod readonly -v ./... || true

.golangci.yml

@@ -1,44 +1,5 @@
 run:
-  concurrency: 4
+  concurrency: 8
-  deadline: 5m
+  timeout: 5m
   issues-exit-code: 1
   tests: true
-
-linters-settings:
-  govet:
-    check-shadowing: true
-    enable:
-      - fieldalignment
-
-linters:
-  enable:
-    - govet
-    - deadcode
-    - errcheck
-    - govet
-    - ineffassign
-    - staticcheck
-    - structcheck
-    - typecheck
-    - unused
-    - varcheck
-    - bodyclose
-    - gci
-    - goconst
-    - gocritic
-    - gosimple
-    - gofmt
-    - gofumpt
-    - goimports
-    - revive
-    - gosec
-    - makezero
-    - misspell
-    - nakedret
-    - nestif
-    - nilerr
-    - noctx
-    - prealloc
-    - unconvert
-    - unparam
-  disable-all: false

README.md

@@ -1,39 +1,34 @@
-# Micro [![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/github.com/unistack-org/micro/v3?tab=overview) [![Status](https://github.com/unistack-org/micro/workflows/build/badge.svg?branch=master)](https://github.com/unistack-org/micro/actions?query=workflow%3Abuild+branch%3Amaster+event%3Apush) [![Lint](https://goreportcard.com/badge/go.unistack.org/micro/v3)](https://goreportcard.com/report/go.unistack.org/micro/v3) [![Coverage](https://codecov.io/gh/unistack-org/micro/branch/v3/graph/badge.svg?token=OZPO2LP7VS)](https://codecov.io/gh/unistack-org/micro)
+# Micro
+![Coverage](https://img.shields.io/badge/Coverage-34.1%25-yellow)
+[![License](https://img.shields.io/:license-apache-blue.svg)](https://opensource.org/licenses/Apache-2.0)
+[![Doc](https://img.shields.io/badge/go.dev-reference-007d9c?logo=go&logoColor=white&style=flat-square)](https://pkg.go.dev/go.unistack.org/micro/v3?tab=overview)
+[![Status](https://git.unistack.org/unistack-org/micro/actions/workflows/job_tests.yml/badge.svg?branch=v3)](https://git.unistack.org/unistack-org/micro/actions?query=workflow%3Abuild+branch%3Av3+event%3Apush)
+[![Lint](https://goreportcard.com/badge/go.unistack.org/micro/v3)](https://goreportcard.com/report/go.unistack.org/micro/v3)
 
 Micro is a standard library for microservices.
 
 ## Overview
 
-Micro provides the core requirements for distributed systems development including RPC and Event driven communication. 
+Micro provides the core requirements for distributed systems development including SYNC and ASYNC communication. 
 
 ## Features
 
-Micro abstracts away the details of distributed systems. Here are the main features.
+Micro abstracts away the details of distributed systems. Main features:
-
-- **Authentication** - Auth is built in as a first class citizen. Authentication and authorization enable secure 
-zero trust networking by providing every service an identity and certificates. This additionally includes rule 
-based access control.
 
 - **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, file, etcd. You can merge the sources and even define fallbacks.
+level config from any source such as env vars, cmdline, file, consul, vault, etc... 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 
-CockroachDB by default. State and persistence becomes a core requirement beyond prototyping and Micro looks to build that into the framework.
+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. When service A needs to speak to service B it needs the location of that service.
+development.
-
-- **Load Balancing** - Client side load balancing built on service discovery. Once we have the addresses of any number of instances 
-of a service we now need a way to decide which node to route to. We use random hashed load balancing to provide even distribution 
-across the services and retry a different node if there's a problem. 
 
 - **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 
 and server handle this by default.
 
-- **Transport** - gRPC or http based request/response with support for bidirectional streaming. We provide an abstraction for synchronous communication. A request made to a service will be automatically resolved, load balanced, dialled and streamed.
+- **Async Messaging** - Pub/Sub is built in as a first class citizen for asynchronous communication and event driven architectures.
-
-- **Async Messaging** - PubSub is built in as a first class citizen for asynchronous communication and event driven architectures.
 Event notifications are a core pattern in micro service development.
 
 - **Synchronization** - Distributed systems are often built in an eventually consistent manner. Support for distributed locking and 
@@ -42,10 +37,6 @@ leadership are built in as a Sync interface. When using an eventually consistent
 - **Pluggable Interfaces** - Micro makes use of Go interfaces for each system abstraction. Because of this these interfaces 
 are pluggable and allows Micro to be runtime agnostic.
 
-## Getting Started
-
-To be created.
-
 ## License
 
 Micro is Apache 2.0 licensed.

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

@@ -46,6 +46,12 @@ type Broker interface {
 	BatchSubscribe(ctx context.Context, topic string, h BatchHandler, opts ...SubscribeOption) (Subscriber, error)
 	// String type of broker
 	String() string
+	// Live returns broker liveness
+	Live() bool
+	// Ready returns broker readiness
+	Ready() bool
+	// Health returns broker health
+	Health() bool
 }
 
 type (

broker/context.go

@@ -15,6 +15,15 @@ func FromContext(ctx context.Context) (Broker, bool) {
 	return c, ok
 }
 
+// MustContext returns broker from passed context
+func MustContext(ctx context.Context) Broker {
+	b, ok := FromContext(ctx)
+	if !ok {
+		panic("missing broker")
+	}
+	return b
+}
+
 // NewContext savess broker in context
 func NewContext(ctx context.Context, s Broker) context.Context {
 	if ctx == nil {

broker/memory/memory.go

@@ -109,7 +109,7 @@ func (m *memoryBroker) Init(opts ...broker.Option) error {
 	m.funcSubscribe = m.fnSubscribe
 	m.funcBatchSubscribe = m.fnBatchSubscribe
 
-	m.opts.Hooks.EachNext(func(hook options.Hook) {
+	m.opts.Hooks.EachPrev(func(hook options.Hook) {
 		switch h := hook.(type) {
 		case broker.HookPublish:
 			m.funcPublish = h(m.funcPublish)
@@ -339,6 +339,18 @@ func (m *memoryBroker) Name() string {
 	return m.opts.Name
 }
 
+func (m *memoryBroker) Live() bool {
+	return true
+}
+
+func (m *memoryBroker) Ready() bool {
+	return true
+}
+
+func (m *memoryBroker) Health() bool {
+	return true
+}
+
 func (m *memoryEvent) Topic() string {
 	return m.topic
 }

broker/memory/memory_test.go

@@ -74,7 +74,7 @@ func TestMemoryBroker(t *testing.T) {
 	topic := "test"
 	count := 10
 
-	fn := func(p broker.Event) error {
+	fn := func(_ broker.Event) error {
 		return nil
 	}
 

broker/noop.go

@@ -25,6 +25,18 @@ func NewBroker(opts ...Option) *NoopBroker {
 	return b
 }
 
+func (b *NoopBroker) Health() bool {
+	return true
+}
+
+func (b *NoopBroker) Live() bool {
+	return true
+}
+
+func (b *NoopBroker) Ready() bool {
+	return true
+}
+
 func (b *NoopBroker) Name() string {
 	return b.opts.Name
 }
@@ -47,7 +59,7 @@ func (b *NoopBroker) Init(opts ...Option) error {
 	b.funcSubscribe = b.fnSubscribe
 	b.funcBatchSubscribe = b.fnBatchSubscribe
 
-	b.opts.Hooks.EachNext(func(hook options.Hook) {
+	b.opts.Hooks.EachPrev(func(hook options.Hook) {
 		switch h := hook.(type) {
 		case HookPublish:
 			b.funcPublish = h(b.funcPublish)

broker/options.go

@@ -16,6 +16,9 @@ import (
 
 // Options struct
 type Options struct {
+	// Name holds the broker name
+	Name string
+
 	// Tracer used for tracing
 	Tracer tracer.Tracer
 	// Register can be used for clustering
@@ -28,23 +31,25 @@ type Options struct {
 	Meter meter.Meter
 	// Context holds external options
 	Context context.Context
+
+	// Wait waits for a collection of goroutines to finish
+	Wait *sync.WaitGroup
 	// TLSConfig holds tls.TLSConfig options
 	TLSConfig *tls.Config
+
 	// ErrorHandler used when broker can't unmarshal incoming message
 	ErrorHandler Handler
 	// BatchErrorHandler used when broker can't unmashal incoming messages
 	BatchErrorHandler BatchHandler
-	// Name holds the broker name
+
-	Name string
 	// Addrs holds the broker address
 	Addrs []string
-	// Wait waits for a collection of goroutines to finish
-	Wait *sync.WaitGroup
-	// GracefulTimeout contains time to wait to finish in flight requests
-	GracefulTimeout time.Duration
 	// Hooks can be run before broker Publish/BatchPublish and
 	// Subscribe/BatchSubscribe methods
 	Hooks options.Hooks
+
+	// GracefulTimeout contains time to wait to finish in flight requests
+	GracefulTimeout time.Duration
 }
 
 // NewOptions create new Options

client/backoff.go

@@ -17,13 +17,13 @@ func BackoffExp(_ context.Context, _ Request, attempts int) (time.Duration, erro
 }
 
 // BackoffInterval specifies randomization interval for backoff func
-func BackoffInterval(min time.Duration, max time.Duration) BackoffFunc {
+func BackoffInterval(minTime time.Duration, maxTime time.Duration) BackoffFunc {
 	return func(_ context.Context, _ Request, attempts int) (time.Duration, error) {
 		td := time.Duration(math.Pow(float64(attempts), math.E)) * time.Millisecond * 100
-		if td < min {
+		if td < minTime {
-			return min, nil
+			return minTime, nil
-		} else if td > max {
+		} else if td > maxTime {
-			return max, nil
+			return maxTime, nil
 		}
 		return td, nil
 	}

client/backoff_test.go

@@ -34,23 +34,23 @@ func TestBackoffExp(t *testing.T) {
 }
 
 func TestBackoffInterval(t *testing.T) {
-	min := 100 * time.Millisecond
+	minTime := 100 * time.Millisecond
-	max := 300 * time.Millisecond
+	maxTime := 300 * time.Millisecond
 
 	r := &testRequest{
 		service: "test",
 		method:  "test",
 	}
 
-	fn := BackoffInterval(min, max)
+	fn := BackoffInterval(minTime, maxTime)
 	for i := 0; i < 5; i++ {
 		d, err := fn(context.TODO(), r, i)
 		if err != nil {
 			t.Fatal(err)
 		}
 
-		if d < min || d > max {
+		if d < minTime || d > maxTime {
-			t.Fatalf("Expected %v < %v < %v", min, d, max)
+			t.Fatalf("Expected %v < %v < %v", minTime, d, maxTime)
 		}
 	}
 }

client/context.go

@@ -15,6 +15,15 @@ func FromContext(ctx context.Context) (Client, bool) {
 	return c, ok
 }
 
+// MustContext get client from context
+func MustContext(ctx context.Context) Client {
+	c, ok := FromContext(ctx)
+	if !ok {
+		panic("missing client")
+	}
+	return c
+}
+
 // NewContext put client in context
 func NewContext(ctx context.Context, c Client) context.Context {
 	if ctx == nil {

client/noop.go

@@ -17,11 +17,6 @@ import (
 	"go.unistack.org/micro/v3/tracer"
 )
 
-// DefaultCodecs will be used to encode/decode data
-var DefaultCodecs = map[string]codec.Codec{
-	"application/octet-stream": codec.NewCodec(),
-}
-
 type noopClient struct {
 	funcPublish      FuncPublish
 	funcBatchPublish FuncBatchPublish
@@ -178,9 +173,6 @@ func (n *noopClient) newCodec(contentType string) (codec.Codec, error) {
 	if cf, ok := n.opts.Codecs[contentType]; ok {
 		return cf, nil
 	}
-	if cf, ok := DefaultCodecs[contentType]; ok {
-		return cf, nil
-	}
 	return nil, codec.ErrUnknownContentType
 }
 
@@ -194,7 +186,7 @@ func (n *noopClient) Init(opts ...Option) error {
 	n.funcPublish = n.fnPublish
 	n.funcBatchPublish = n.fnBatchPublish
 
-	n.opts.Hooks.EachNext(func(hook options.Hook) {
+	n.opts.Hooks.EachPrev(func(hook options.Hook) {
 		switch h := hook.(type) {
 		case HookCall:
 			n.funcCall = h(n.funcCall)
@@ -222,7 +214,7 @@ func (n *noopClient) Call(ctx context.Context, req Request, rsp interface{}, opt
 	ts := time.Now()
 	n.opts.Meter.Counter(semconv.ClientRequestInflight, "endpoint", req.Endpoint()).Inc()
 	var sp tracer.Span
-	ctx, sp = n.opts.Tracer.Start(ctx, req.Endpoint()+" rpc-client",
+	ctx, sp = n.opts.Tracer.Start(ctx, "rpc-client",
 		tracer.WithSpanKind(tracer.SpanKindClient),
 		tracer.WithSpanLabels("endpoint", req.Endpoint()),
 	)
@@ -298,7 +290,7 @@ func (n *noopClient) fnCall(ctx context.Context, req Request, rsp interface{}, o
 		// call backoff first. Someone may want an initial start delay
 		t, err := callOpts.Backoff(ctx, req, i)
 		if err != nil {
-			return errors.InternalServerError("go.micro.client", err.Error())
+			return errors.InternalServerError("go.micro.client", "%s", err)
 		}
 
 		// only sleep if greater than 0
@@ -312,7 +304,7 @@ func (n *noopClient) fnCall(ctx context.Context, req Request, rsp interface{}, o
 			// TODO apply any filtering here
 			routes, err = n.opts.Lookup(ctx, req, callOpts)
 			if err != nil {
-				return errors.InternalServerError("go.micro.client", err.Error())
+				return errors.InternalServerError("go.micro.client", "%s", err)
 			}
 
 			// balance the list of nodes
@@ -372,7 +364,7 @@ func (n *noopClient) fnCall(ctx context.Context, req Request, rsp interface{}, o
 	return gerr
 }
 
-func (n *noopClient) NewRequest(service, endpoint string, req interface{}, opts ...RequestOption) Request {
+func (n *noopClient) NewRequest(service, endpoint string, _ interface{}, _ ...RequestOption) Request {
 	return &noopRequest{service: service, endpoint: endpoint}
 }
 
@@ -385,7 +377,7 @@ func (n *noopClient) Stream(ctx context.Context, req Request, opts ...CallOption
 	ts := time.Now()
 	n.opts.Meter.Counter(semconv.ClientRequestInflight, "endpoint", req.Endpoint()).Inc()
 	var sp tracer.Span
-	ctx, sp = n.opts.Tracer.Start(ctx, req.Endpoint()+" rpc-client",
+	ctx, sp = n.opts.Tracer.Start(ctx, "rpc-client",
 		tracer.WithSpanKind(tracer.SpanKindClient),
 		tracer.WithSpanLabels("endpoint", req.Endpoint()),
 	)
@@ -466,7 +458,7 @@ func (n *noopClient) fnStream(ctx context.Context, req Request, opts ...CallOpti
 		// call backoff first. Someone may want an initial start delay
 		t, cerr := callOpts.Backoff(ctx, req, i)
 		if cerr != nil {
-			return nil, errors.InternalServerError("go.micro.client", cerr.Error())
+			return nil, errors.InternalServerError("go.micro.client", "%s", cerr)
 		}
 
 		// only sleep if greater than 0
@@ -480,7 +472,7 @@ func (n *noopClient) fnStream(ctx context.Context, req Request, opts ...CallOpti
 			// TODO apply any filtering here
 			routes, err = n.opts.Lookup(ctx, req, callOpts)
 			if err != nil {
-				return nil, errors.InternalServerError("go.micro.client", err.Error())
+				return nil, errors.InternalServerError("go.micro.client", "%s", err)
 			}
 
 			// balance the list of nodes
@@ -546,7 +538,7 @@ func (n *noopClient) fnStream(ctx context.Context, req Request, opts ...CallOpti
 	return nil, grr
 }
 
-func (n *noopClient) stream(ctx context.Context, addr string, req Request, opts CallOptions) (Stream, error) {
+func (n *noopClient) stream(ctx context.Context, _ string, _ Request, _ CallOptions) (Stream, error) {
 	return &noopStream{ctx: ctx}, nil
 }
 
@@ -588,7 +580,6 @@ func (n *noopClient) publish(ctx context.Context, ps []Message, opts ...PublishO
 
 	for _, p := range ps {
 		md := metadata.Copy(omd)
-		md[metadata.HeaderContentType] = p.ContentType()
 		topic := p.Topic()
 		if len(exchange) > 0 {
 			topic = exchange
@@ -600,6 +591,8 @@ func (n *noopClient) publish(ctx context.Context, ps []Message, opts ...PublishO
 			md.Set(k, v)
 		}
 
+		md[metadata.HeaderContentType] = p.ContentType()
+
 		var body []byte
 
 		// passed in raw data
@@ -609,13 +602,13 @@ func (n *noopClient) publish(ctx context.Context, ps []Message, opts ...PublishO
 			// use codec for payload
 			cf, err := n.newCodec(p.ContentType())
 			if err != nil {
-				return errors.InternalServerError("go.micro.client", err.Error())
+				return errors.InternalServerError("go.micro.client", "%s", err)
 			}
 
 			// set the body
 			b, err := cf.Marshal(p.Payload())
 			if err != nil {
-				return errors.InternalServerError("go.micro.client", err.Error())
+				return errors.InternalServerError("go.micro.client", "%s", err)
 			}
 			body = b
 		}

client/noop_test.go

@@ -3,6 +3,8 @@ package client
 import (
 	"context"
 	"testing"
+
+	"go.unistack.org/micro/v3/codec"
 )
 
 type testHook struct {
@@ -19,7 +21,7 @@ func (t *testHook) Publish(fn FuncPublish) FuncPublish {
 func TestNoopHook(t *testing.T) {
 	h := &testHook{}
 
-	c := NewClient(Hooks(HookPublish(h.Publish)))
+	c := NewClient(Codec("application/octet-stream", codec.NewCodec()), Hooks(HookPublish(h.Publish)))
 
 	if err := c.Init(); err != nil {
 		t.Fatal(err)

client/options.go

@@ -11,7 +11,6 @@ import (
 	"go.unistack.org/micro/v3/logger"
 	"go.unistack.org/micro/v3/metadata"
 	"go.unistack.org/micro/v3/meter"
-	"go.unistack.org/micro/v3/network/transport"
 	"go.unistack.org/micro/v3/options"
 	"go.unistack.org/micro/v3/register"
 	"go.unistack.org/micro/v3/router"
@@ -22,8 +21,16 @@ import (
 
 // Options holds client options
 type Options struct {
-	// Transport used for transfer messages
+	// Codecs map
-	Transport transport.Transport
+	Codecs map[string]codec.Codec
+
+	// Proxy is used for proxy requests
+	Proxy string
+	// ContentType is used to select codec
+	ContentType string
+	// Name is the client name
+	Name string
+
 	// Selector used to select needed address
 	Selector selector.Selector
 	// Logger used to log messages
@@ -38,31 +45,28 @@ type Options struct {
 	Context context.Context
 	// Router used to get route
 	Router router.Router
+
 	// TLSConfig specifies tls.Config for secure connection
 	TLSConfig *tls.Config
-	// Codecs map
+
-	Codecs map[string]codec.Codec
 	// Lookup func used to get destination addr
 	Lookup LookupFunc
-	// Proxy is used for proxy requests
+	// ContextDialer used to connect
-	Proxy string
+	ContextDialer func(context.Context, string) (net.Conn, error)
-	// ContentType is used to select codec
+
-	ContentType string
-	// Name is the client name
-	Name string
 	// Wrappers contains wrappers
 	Wrappers []Wrapper
+	// Hooks can be run before broker Publish/BatchPublish and
+	// Subscribe/BatchSubscribe methods
+	Hooks options.Hooks
+
 	// CallOptions contains default CallOptions
 	CallOptions CallOptions
+
 	// PoolSize connection pool size
 	PoolSize int
 	// PoolTTL connection pool ttl
 	PoolTTL time.Duration
-	// ContextDialer used to connect
-	ContextDialer func(context.Context, string) (net.Conn, error)
-	// Hooks can be run before broker Publish/BatchPublish and
-	// Subscribe/BatchSubscribe methods
-	Hooks options.Hooks
 }
 
 // NewCallOptions creates new call options struct
@@ -76,6 +80,16 @@ func NewCallOptions(opts ...CallOption) CallOptions {
 
 // CallOptions holds client call options
 type CallOptions struct {
+	// RequestMetadata holds additional metadata for call
+	RequestMetadata metadata.Metadata
+
+	// Network name
+	Network string
+	// Content-Type
+	ContentType string
+	// AuthToken string
+	AuthToken string
+
 	// Selector selects addr
 	Selector selector.Selector
 	// Context used for deadline
@@ -83,33 +97,30 @@ type CallOptions struct {
 	// Router used for route
 	Router router.Router
 	// Retry func used for retries
+
+	// ResponseMetadata holds additional metadata from call
+	ResponseMetadata *metadata.Metadata
+
 	Retry RetryFunc
 	// Backoff func used for backoff when retry
 	Backoff BackoffFunc
-	// Network name
+	// ContextDialer used to connect
-	Network string
+	ContextDialer func(context.Context, string) (net.Conn, error)
-	// Content-Type
+
-	ContentType string
-	// AuthToken string
-	AuthToken string
 	// Address specifies static addr list
 	Address []string
 	// SelectOptions selector options
 	SelectOptions []selector.SelectOption
+
 	// StreamTimeout stream timeout
 	StreamTimeout time.Duration
 	// RequestTimeout request timeout
 	RequestTimeout time.Duration
-	// RequestMetadata holds additional metadata for call
+
-	RequestMetadata metadata.Metadata
-	// ResponseMetadata holds additional metadata from call
-	ResponseMetadata *metadata.Metadata
 	// DialTimeout dial timeout
 	DialTimeout time.Duration
 	// Retries specifies retries num
 	Retries int
-	// ContextDialer used to connect
-	ContextDialer func(context.Context, string) (net.Conn, error)
 }
 
 // ContextDialer pass ContextDialer to client
@@ -187,25 +198,23 @@ func NewOptions(opts ...Option) Options {
 	options := Options{
 		Context:     context.Background(),
 		ContentType: DefaultContentType,
-		Codecs:      DefaultCodecs,
+		Codecs:      make(map[string]codec.Codec),
 		CallOptions: CallOptions{
 			Context:        context.Background(),
 			Backoff:        DefaultBackoff,
 			Retry:          DefaultRetry,
 			Retries:        DefaultRetries,
 			RequestTimeout: DefaultRequestTimeout,
-			DialTimeout:    transport.DefaultDialTimeout,
 		},
-		Lookup:    LookupRoute,
+		Lookup:   LookupRoute,
-		PoolSize:  DefaultPoolSize,
+		PoolSize: DefaultPoolSize,
-		PoolTTL:   DefaultPoolTTL,
+		PoolTTL:  DefaultPoolTTL,
-		Selector:  random.NewSelector(),
+		Selector: random.NewSelector(),
-		Logger:    logger.DefaultLogger,
+		Logger:   logger.DefaultLogger,
-		Broker:    broker.DefaultBroker,
+		Broker:   broker.DefaultBroker,
-		Meter:     meter.DefaultMeter,
+		Meter:    meter.DefaultMeter,
-		Tracer:    tracer.DefaultTracer,
+		Tracer:   tracer.DefaultTracer,
-		Router:    router.DefaultRouter,
+		Router:   router.DefaultRouter,
-		Transport: transport.DefaultTransport,
 	}
 
 	for _, o := range opts {
@@ -278,13 +287,6 @@ func PoolTTL(d time.Duration) Option {
 	}
 }
 
-// Transport to use for communication e.g http, rabbitmq, etc
-func Transport(t transport.Transport) Option {
-	return func(o *Options) {
-		o.Transport = t
-	}
-}
-
 // Register sets the routers register
 func Register(r register.Register) Option {
 	return func(o *Options) {
@@ -334,14 +336,6 @@ func TLSConfig(t *tls.Config) Option {
 	return func(o *Options) {
 		// set the internal tls
 		o.TLSConfig = t
-
-		// set the default transport if one is not
-		// already set. Required for Init call below.
-
-		// set the transport tls
-		_ = o.Transport.Init(
-			transport.TLSConfig(t),
-		)
 	}
 }
 
@@ -507,13 +501,6 @@ func WithAuthToken(t string) CallOption {
 	}
 }
 
-// WithNetwork is a CallOption which sets the network attribute
-func WithNetwork(n string) CallOption {
-	return func(o *CallOptions) {
-		o.Network = n
-	}
-}
-
 // WithRouter sets the router to use for this call
 func WithRouter(r router.Router) CallOption {
 	return func(o *CallOptions) {

cluster/cluster.go

@@ -38,4 +38,10 @@ type Cluster interface {
 	Broadcast(ctx context.Context, msg Message, filter ...string) error
 	// Unicast send message to single member in cluster
 	Unicast(ctx context.Context, node Node, msg Message) error
+	// Live returns cluster liveness
+	Live() bool
+	// Ready returns cluster readiness
+	Ready() bool
+	// Health returns cluster health
+	Health() bool
 }

cluster/hasql/cluster.go

@@ -0,0 +1,235 @@
+package sql
+
+import (
+	"context"
+	"database/sql"
+	"reflect"
+	"unsafe"
+
+	"golang.yandex/hasql/v2"
+)
+
+func newSQLRowError() *sql.Row {
+	row := &sql.Row{}
+	t := reflect.TypeOf(row).Elem()
+	field, _ := t.FieldByName("err")
+	rowPtr := unsafe.Pointer(row)
+	errFieldPtr := unsafe.Pointer(uintptr(rowPtr) + field.Offset)
+	errPtr := (*error)(errFieldPtr)
+	*errPtr = ErrorNoAliveNodes
+	return row
+}
+
+type ClusterQuerier interface {
+	Querier
+	WaitForNodes(ctx context.Context, criterion ...hasql.NodeStateCriterion) error
+}
+
+type Cluster struct {
+	hasql   *hasql.Cluster[Querier]
+	options ClusterOptions
+}
+
+// NewCluster returns [Querier] that provides cluster of nodes
+func NewCluster[T Querier](opts ...ClusterOption) (ClusterQuerier, error) {
+	options := ClusterOptions{Context: context.Background()}
+	for _, opt := range opts {
+		opt(&options)
+	}
+	if options.NodeChecker == nil {
+		return nil, ErrClusterChecker
+	}
+	if options.NodeDiscoverer == nil {
+		return nil, ErrClusterDiscoverer
+	}
+	if options.NodePicker == nil {
+		return nil, ErrClusterPicker
+	}
+
+	if options.Retries < 1 {
+		options.Retries = 1
+	}
+
+	if options.NodeStateCriterion == 0 {
+		options.NodeStateCriterion = hasql.Primary
+	}
+
+	options.Options = append(options.Options, hasql.WithNodePicker(options.NodePicker))
+	if p, ok := options.NodePicker.(*CustomPicker[Querier]); ok {
+		p.opts.Priority = options.NodePriority
+	}
+
+	c, err := hasql.NewCluster(
+		options.NodeDiscoverer,
+		options.NodeChecker,
+		options.Options...,
+	)
+	if err != nil {
+		return nil, err
+	}
+
+	return &Cluster{hasql: c, options: options}, nil
+}
+
+func (c *Cluster) BeginTx(ctx context.Context, opts *sql.TxOptions) (*sql.Tx, error) {
+	var tx *sql.Tx
+	var err error
+
+	retries := 0
+	c.hasql.NodesIter(c.getNodeStateCriterion(ctx))(func(n *hasql.Node[Querier]) bool {
+		for ; retries < c.options.Retries; retries++ {
+			if tx, err = n.DB().BeginTx(ctx, opts); err != nil && retries >= c.options.Retries {
+				return true
+			}
+		}
+		return false
+	})
+
+	if tx == nil && err == nil {
+		err = ErrorNoAliveNodes
+	}
+
+	return tx, err
+}
+
+func (c *Cluster) Close() error {
+	return c.hasql.Close()
+}
+
+func (c *Cluster) Conn(ctx context.Context) (*sql.Conn, error) {
+	var conn *sql.Conn
+	var err error
+
+	retries := 0
+	c.hasql.NodesIter(c.getNodeStateCriterion(ctx))(func(n *hasql.Node[Querier]) bool {
+		for ; retries < c.options.Retries; retries++ {
+			if conn, err = n.DB().Conn(ctx); err != nil && retries >= c.options.Retries {
+				return true
+			}
+		}
+		return false
+	})
+
+	if conn == nil && err == nil {
+		err = ErrorNoAliveNodes
+	}
+
+	return conn, err
+}
+
+func (c *Cluster) ExecContext(ctx context.Context, query string, args ...interface{}) (sql.Result, error) {
+	var res sql.Result
+	var err error
+
+	retries := 0
+	c.hasql.NodesIter(c.getNodeStateCriterion(ctx))(func(n *hasql.Node[Querier]) bool {
+		for ; retries < c.options.Retries; retries++ {
+			if res, err = n.DB().ExecContext(ctx, query, args...); err != nil && retries >= c.options.Retries {
+				return true
+			}
+		}
+		return false
+	})
+
+	if res == nil && err == nil {
+		err = ErrorNoAliveNodes
+	}
+
+	return res, err
+}
+
+func (c *Cluster) PrepareContext(ctx context.Context, query string) (*sql.Stmt, error) {
+	var res *sql.Stmt
+	var err error
+
+	retries := 0
+	c.hasql.NodesIter(c.getNodeStateCriterion(ctx))(func(n *hasql.Node[Querier]) bool {
+		for ; retries < c.options.Retries; retries++ {
+			if res, err = n.DB().PrepareContext(ctx, query); err != nil && retries >= c.options.Retries {
+				return true
+			}
+		}
+		return false
+	})
+
+	if res == nil && err == nil {
+		err = ErrorNoAliveNodes
+	}
+
+	return res, err
+}
+
+func (c *Cluster) QueryContext(ctx context.Context, query string, args ...interface{}) (*sql.Rows, error) {
+	var res *sql.Rows
+	var err error
+
+	retries := 0
+	c.hasql.NodesIter(c.getNodeStateCriterion(ctx))(func(n *hasql.Node[Querier]) bool {
+		for ; retries < c.options.Retries; retries++ {
+			if res, err = n.DB().QueryContext(ctx, query); err != nil && err != sql.ErrNoRows && retries >= c.options.Retries {
+				return true
+			}
+		}
+		return false
+	})
+
+	if res == nil && err == nil {
+		err = ErrorNoAliveNodes
+	}
+
+	return res, err
+}
+
+func (c *Cluster) QueryRowContext(ctx context.Context, query string, args ...interface{}) *sql.Row {
+	var res *sql.Row
+
+	retries := 0
+	c.hasql.NodesIter(c.getNodeStateCriterion(ctx))(func(n *hasql.Node[Querier]) bool {
+		for ; retries < c.options.Retries; retries++ {
+			res = n.DB().QueryRowContext(ctx, query, args...)
+			if res.Err() == nil {
+				return false
+			} else if res.Err() != nil && retries >= c.options.Retries {
+				return false
+			}
+		}
+		return true
+	})
+
+	if res == nil {
+		res = newSQLRowError()
+	}
+
+	return res
+}
+
+func (c *Cluster) PingContext(ctx context.Context) error {
+	var err error
+	var ok bool
+
+	retries := 0
+	c.hasql.NodesIter(c.getNodeStateCriterion(ctx))(func(n *hasql.Node[Querier]) bool {
+		ok = true
+		for ; retries < c.options.Retries; retries++ {
+			if err = n.DB().PingContext(ctx); err != nil && retries >= c.options.Retries {
+				return true
+			}
+		}
+		return false
+	})
+
+	if !ok {
+		err = ErrorNoAliveNodes
+	}
+
+	return err
+}
+
+func (c *Cluster) WaitForNodes(ctx context.Context, criterions ...hasql.NodeStateCriterion) error {
+	for _, criterion := range criterions {
+		if _, err := c.hasql.WaitForNode(ctx, criterion); err != nil {
+			return err
+		}
+	}
+	return nil
+}

cluster/hasql/cluster_test.go

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

cluster/hasql/db.go

@@ -0,0 +1,25 @@
+package sql
+
+import (
+	"context"
+	"database/sql"
+)
+
+type Querier interface {
+	// Basic connection methods
+	PingContext(ctx context.Context) error
+	Close() error
+
+	// Query methods with context
+	ExecContext(ctx context.Context, query string, args ...interface{}) (sql.Result, error)
+	QueryContext(ctx context.Context, query string, args ...interface{}) (*sql.Rows, error)
+	QueryRowContext(ctx context.Context, query string, args ...interface{}) *sql.Row
+
+	// Prepared statements with context
+	PrepareContext(ctx context.Context, query string) (*sql.Stmt, error)
+
+	// Transaction management with context
+	BeginTx(ctx context.Context, opts *sql.TxOptions) (*sql.Tx, error)
+
+	Conn(ctx context.Context) (*sql.Conn, error)
+}

cluster/hasql/driver.go

@@ -0,0 +1,295 @@
+package sql
+
+import (
+	"context"
+	"database/sql"
+	"database/sql/driver"
+	"io"
+	"sync"
+	"time"
+)
+
+// OpenDBWithCluster creates a [*sql.DB] that uses the [ClusterQuerier]
+func OpenDBWithCluster(db ClusterQuerier) (*sql.DB, error) {
+	driver := NewClusterDriver(db)
+	connector, err := driver.OpenConnector("")
+	if err != nil {
+		return nil, err
+	}
+	return sql.OpenDB(connector), nil
+}
+
+// ClusterDriver implements [driver.Driver] and driver.Connector for an existing [Querier]
+type ClusterDriver struct {
+	db ClusterQuerier
+}
+
+// NewClusterDriver creates a new [driver.Driver] that uses an existing [ClusterQuerier]
+func NewClusterDriver(db ClusterQuerier) *ClusterDriver {
+	return &ClusterDriver{db: db}
+}
+
+// Open implements [driver.Driver.Open]
+func (d *ClusterDriver) Open(name string) (driver.Conn, error) {
+	return d.Connect(context.Background())
+}
+
+// OpenConnector implements [driver.DriverContext.OpenConnector]
+func (d *ClusterDriver) OpenConnector(name string) (driver.Connector, error) {
+	return d, nil
+}
+
+// Connect implements [driver.Connector.Connect]
+func (d *ClusterDriver) Connect(ctx context.Context) (driver.Conn, error) {
+	conn, err := d.db.Conn(ctx)
+	if err != nil {
+		return nil, err
+	}
+	return &dbConn{conn: conn}, nil
+}
+
+// Driver implements [driver.Connector.Driver]
+func (d *ClusterDriver) Driver() driver.Driver {
+	return d
+}
+
+// dbConn implements driver.Conn with both context and legacy methods
+type dbConn struct {
+	conn *sql.Conn
+	mu   sync.Mutex
+}
+
+// Prepare implements [driver.Conn.Prepare] (legacy method)
+func (c *dbConn) Prepare(query string) (driver.Stmt, error) {
+	return c.PrepareContext(context.Background(), query)
+}
+
+// PrepareContext implements [driver.ConnPrepareContext.PrepareContext]
+func (c *dbConn) PrepareContext(ctx context.Context, query string) (driver.Stmt, error) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	stmt, err := c.conn.PrepareContext(ctx, query)
+	if err != nil {
+		return nil, err
+	}
+
+	return &dbStmt{stmt: stmt}, nil
+}
+
+// Exec implements [driver.Execer.Exec] (legacy method)
+func (c *dbConn) Exec(query string, args []driver.Value) (driver.Result, error) {
+	namedArgs := make([]driver.NamedValue, len(args))
+	for i, value := range args {
+		namedArgs[i] = driver.NamedValue{Value: value}
+	}
+	return c.ExecContext(context.Background(), query, namedArgs)
+}
+
+// ExecContext implements [driver.ExecerContext.ExecContext]
+func (c *dbConn) ExecContext(ctx context.Context, query string, args []driver.NamedValue) (driver.Result, error) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	// Convert driver.NamedValue to any
+	interfaceArgs := make([]any, len(args))
+	for i, arg := range args {
+		interfaceArgs[i] = arg.Value
+	}
+
+	return c.conn.ExecContext(ctx, query, interfaceArgs...)
+}
+
+// Query implements [driver.Queryer.Query] (legacy method)
+func (c *dbConn) Query(query string, args []driver.Value) (driver.Rows, error) {
+	namedArgs := make([]driver.NamedValue, len(args))
+	for i, value := range args {
+		namedArgs[i] = driver.NamedValue{Value: value}
+	}
+	return c.QueryContext(context.Background(), query, namedArgs)
+}
+
+// QueryContext implements [driver.QueryerContext.QueryContext]
+func (c *dbConn) QueryContext(ctx context.Context, query string, args []driver.NamedValue) (driver.Rows, error) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	// Convert driver.NamedValue to any
+	interfaceArgs := make([]any, len(args))
+	for i, arg := range args {
+		interfaceArgs[i] = arg.Value
+	}
+
+	rows, err := c.conn.QueryContext(ctx, query, interfaceArgs...)
+	if err != nil {
+		return nil, err
+	}
+
+	return &dbRows{rows: rows}, nil
+}
+
+// Begin implements [driver.Conn.Begin] (legacy method)
+func (c *dbConn) Begin() (driver.Tx, error) {
+	return c.BeginTx(context.Background(), driver.TxOptions{})
+}
+
+// BeginTx implements [driver.ConnBeginTx.BeginTx]
+func (c *dbConn) BeginTx(ctx context.Context, opts driver.TxOptions) (driver.Tx, error) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	sqlOpts := &sql.TxOptions{
+		Isolation: sql.IsolationLevel(opts.Isolation),
+		ReadOnly:  opts.ReadOnly,
+	}
+
+	tx, err := c.conn.BeginTx(ctx, sqlOpts)
+	if err != nil {
+		return nil, err
+	}
+
+	return &dbTx{tx: tx}, nil
+}
+
+// Ping implements [driver.Pinger.Ping]
+func (c *dbConn) Ping(ctx context.Context) error {
+	return c.conn.PingContext(ctx)
+}
+
+// Close implements [driver.Conn.Close]
+func (c *dbConn) Close() error {
+	return c.conn.Close()
+}
+
+// IsValid implements [driver.Validator.IsValid]
+func (c *dbConn) IsValid() bool {
+	// Ping with a short timeout to check if the connection is still valid
+	ctx, cancel := context.WithTimeout(context.Background(), 1*time.Second)
+	defer cancel()
+
+	return c.conn.PingContext(ctx) == nil
+}
+
+// dbStmt implements [driver.Stmt] with both context and legacy methods
+type dbStmt struct {
+	stmt *sql.Stmt
+	mu   sync.Mutex
+}
+
+// Close implements [driver.Stmt.Close]
+func (s *dbStmt) Close() error {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	return s.stmt.Close()
+}
+
+// Close implements [driver.Stmt.NumInput]
+func (s *dbStmt) NumInput() int {
+	return -1 // Number of parameters is unknown
+}
+
+// Exec implements [driver.Stmt.Exec] (legacy method)
+func (s *dbStmt) Exec(args []driver.Value) (driver.Result, error) {
+	namedArgs := make([]driver.NamedValue, len(args))
+	for i, value := range args {
+		namedArgs[i] = driver.NamedValue{Value: value}
+	}
+	return s.ExecContext(context.Background(), namedArgs)
+}
+
+// ExecContext implements [driver.StmtExecContext.ExecContext]
+func (s *dbStmt) ExecContext(ctx context.Context, args []driver.NamedValue) (driver.Result, error) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	interfaceArgs := make([]any, len(args))
+	for i, arg := range args {
+		interfaceArgs[i] = arg.Value
+	}
+	return s.stmt.ExecContext(ctx, interfaceArgs...)
+}
+
+// Query implements [driver.Stmt.Query] (legacy method)
+func (s *dbStmt) Query(args []driver.Value) (driver.Rows, error) {
+	namedArgs := make([]driver.NamedValue, len(args))
+	for i, value := range args {
+		namedArgs[i] = driver.NamedValue{Value: value}
+	}
+	return s.QueryContext(context.Background(), namedArgs)
+}
+
+// QueryContext implements [driver.StmtQueryContext.QueryContext]
+func (s *dbStmt) QueryContext(ctx context.Context, args []driver.NamedValue) (driver.Rows, error) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+
+	interfaceArgs := make([]any, len(args))
+	for i, arg := range args {
+		interfaceArgs[i] = arg.Value
+	}
+
+	rows, err := s.stmt.QueryContext(ctx, interfaceArgs...)
+	if err != nil {
+		return nil, err
+	}
+
+	return &dbRows{rows: rows}, nil
+}
+
+// dbRows implements [driver.Rows]
+type dbRows struct {
+	rows *sql.Rows
+}
+
+// Columns implements [driver.Rows.Columns]
+func (r *dbRows) Columns() []string {
+	cols, err := r.rows.Columns()
+	if err != nil {
+		// This shouldn't happen if the query was successful
+		return []string{}
+	}
+	return cols
+}
+
+// Close implements [driver.Rows.Close]
+func (r *dbRows) Close() error {
+	return r.rows.Close()
+}
+
+// Next implements [driver.Rows.Next]
+func (r *dbRows) Next(dest []driver.Value) error {
+	if !r.rows.Next() {
+		if err := r.rows.Err(); err != nil {
+			return err
+		}
+		return io.EOF
+	}
+
+	// Create a slice of interfaces to scan into
+	scanArgs := make([]any, len(dest))
+	for i := range scanArgs {
+		scanArgs[i] = &dest[i]
+	}
+
+	return r.rows.Scan(scanArgs...)
+}
+
+// dbTx implements [driver.Tx]
+type dbTx struct {
+	tx *sql.Tx
+	mu sync.Mutex
+}
+
+// Commit implements [driver.Tx.Commit]
+func (t *dbTx) Commit() error {
+	t.mu.Lock()
+	defer t.mu.Unlock()
+	return t.tx.Commit()
+}
+
+// Rollback implements [driver.Tx.Rollback]
+func (t *dbTx) Rollback() error {
+	t.mu.Lock()
+	defer t.mu.Unlock()
+	return t.tx.Rollback()
+}

cluster/hasql/driver_test.go

@@ -0,0 +1,141 @@
+package sql
+
+import (
+	"context"
+	"testing"
+	"time"
+
+	"github.com/DATA-DOG/go-sqlmock"
+	"golang.yandex/hasql/v2"
+)
+
+func TestDriver(t *testing.T) {
+	dbMaster, dbMasterMock, err := sqlmock.New(sqlmock.MonitorPingsOption(true))
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer dbMaster.Close()
+	dbMasterMock.MatchExpectationsInOrder(false)
+
+	dbMasterMock.ExpectQuery(`.*pg_is_in_recovery.*`).WillReturnRows(
+		sqlmock.NewRowsWithColumnDefinition(
+			sqlmock.NewColumn("role").OfType("int8", 0),
+			sqlmock.NewColumn("replication_lag").OfType("int8", 0)).
+			AddRow(1, 0)).
+		RowsWillBeClosed().
+		WithoutArgs()
+
+	dbMasterMock.ExpectQuery(`SELECT node_name as name`).WillReturnRows(
+		sqlmock.NewRows([]string{"name"}).
+			AddRow("master-dc1"))
+
+	dbDRMaster, dbDRMasterMock, err := sqlmock.New(sqlmock.MonitorPingsOption(true))
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer dbDRMaster.Close()
+	dbDRMasterMock.MatchExpectationsInOrder(false)
+
+	dbDRMasterMock.ExpectQuery(`.*pg_is_in_recovery.*`).WillReturnRows(
+		sqlmock.NewRowsWithColumnDefinition(
+			sqlmock.NewColumn("role").OfType("int8", 0),
+			sqlmock.NewColumn("replication_lag").OfType("int8", 0)).
+			AddRow(2, 40)).
+		RowsWillBeClosed().
+		WithoutArgs()
+
+	dbDRMasterMock.ExpectQuery(`SELECT node_name as name`).WillReturnRows(
+		sqlmock.NewRows([]string{"name"}).
+			AddRow("drmaster1-dc2"))
+
+	dbDRMasterMock.ExpectQuery(`SELECT node_name as name`).WillReturnRows(
+		sqlmock.NewRows([]string{"name"}).
+			AddRow("drmaster"))
+
+	dbSlaveDC1, dbSlaveDC1Mock, err := sqlmock.New(sqlmock.MonitorPingsOption(true))
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer dbSlaveDC1.Close()
+	dbSlaveDC1Mock.MatchExpectationsInOrder(false)
+
+	dbSlaveDC1Mock.ExpectQuery(`.*pg_is_in_recovery.*`).WillReturnRows(
+		sqlmock.NewRowsWithColumnDefinition(
+			sqlmock.NewColumn("role").OfType("int8", 0),
+			sqlmock.NewColumn("replication_lag").OfType("int8", 0)).
+			AddRow(2, 50)).
+		RowsWillBeClosed().
+		WithoutArgs()
+
+	dbSlaveDC1Mock.ExpectQuery(`SELECT node_name as name`).WillReturnRows(
+		sqlmock.NewRows([]string{"name"}).
+			AddRow("slave-dc1"))
+
+	dbSlaveDC2, dbSlaveDC2Mock, err := sqlmock.New(sqlmock.MonitorPingsOption(true))
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer dbSlaveDC2.Close()
+	dbSlaveDC1Mock.MatchExpectationsInOrder(false)
+
+	dbSlaveDC2Mock.ExpectQuery(`.*pg_is_in_recovery.*`).WillReturnRows(
+		sqlmock.NewRowsWithColumnDefinition(
+			sqlmock.NewColumn("role").OfType("int8", 0),
+			sqlmock.NewColumn("replication_lag").OfType("int8", 0)).
+			AddRow(2, 50)).
+		RowsWillBeClosed().
+		WithoutArgs()
+
+	dbSlaveDC2Mock.ExpectQuery(`SELECT node_name as name`).WillReturnRows(
+		sqlmock.NewRows([]string{"name"}).
+			AddRow("slave-dc1"))
+
+	tctx, cancel := context.WithTimeout(t.Context(), 10*time.Second)
+	defer cancel()
+
+	c, err := NewCluster[Querier](
+		WithClusterContext(tctx),
+		WithClusterNodeChecker(hasql.PostgreSQLChecker),
+		WithClusterNodePicker(NewCustomPicker[Querier](
+			CustomPickerMaxLag(100),
+		)),
+		WithClusterNodes(
+			ClusterNode{"slave-dc1", dbSlaveDC1, 1},
+			ClusterNode{"master-dc1", dbMaster, 1},
+			ClusterNode{"slave-dc2", dbSlaveDC2, 2},
+			ClusterNode{"drmaster1-dc2", dbDRMaster, 0},
+		),
+		WithClusterOptions(
+			hasql.WithUpdateInterval[Querier](2*time.Second),
+			hasql.WithUpdateTimeout[Querier](1*time.Second),
+		),
+	)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer c.Close()
+
+	if err = c.WaitForNodes(tctx, hasql.Primary, hasql.Standby); err != nil {
+		t.Fatal(err)
+	}
+
+	db, err := OpenDBWithCluster(c)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// Use context methods
+	row := db.QueryRowContext(NodeStateCriterion(t.Context(), hasql.Primary), "SELECT node_name as name")
+	if err = row.Err(); err != nil {
+		t.Fatal(err)
+	}
+
+	nodeName := ""
+	if err = row.Scan(&nodeName); err != nil {
+		t.Fatal(err)
+	}
+
+	if nodeName != "master-dc1" {
+		t.Fatalf("invalid node_name %s != %s", "master-dc1", nodeName)
+	}
+}

cluster/hasql/error.go

@@ -0,0 +1,10 @@
+package sql
+
+import "errors"
+
+var (
+	ErrClusterChecker    = errors.New("cluster node checker required")
+	ErrClusterDiscoverer = errors.New("cluster node discoverer required")
+	ErrClusterPicker     = errors.New("cluster node picker required")
+	ErrorNoAliveNodes    = errors.New("cluster no alive nodes")
+)

cluster/hasql/options.go

@@ -0,0 +1,110 @@
+package sql
+
+import (
+	"context"
+	"math"
+
+	"golang.yandex/hasql/v2"
+)
+
+// ClusterOptions contains cluster specific options
+type ClusterOptions struct {
+	NodeChecker        hasql.NodeChecker
+	NodePicker         hasql.NodePicker[Querier]
+	NodeDiscoverer     hasql.NodeDiscoverer[Querier]
+	Options            []hasql.ClusterOpt[Querier]
+	Context            context.Context
+	Retries            int
+	NodePriority       map[string]int32
+	NodeStateCriterion hasql.NodeStateCriterion
+}
+
+// ClusterOption apply cluster options to ClusterOptions
+type ClusterOption func(*ClusterOptions)
+
+// WithClusterNodeChecker pass hasql.NodeChecker to cluster options
+func WithClusterNodeChecker(c hasql.NodeChecker) ClusterOption {
+	return func(o *ClusterOptions) {
+		o.NodeChecker = c
+	}
+}
+
+// WithClusterNodePicker pass hasql.NodePicker to cluster options
+func WithClusterNodePicker(p hasql.NodePicker[Querier]) ClusterOption {
+	return func(o *ClusterOptions) {
+		o.NodePicker = p
+	}
+}
+
+// WithClusterNodeDiscoverer pass hasql.NodeDiscoverer to cluster options
+func WithClusterNodeDiscoverer(d hasql.NodeDiscoverer[Querier]) ClusterOption {
+	return func(o *ClusterOptions) {
+		o.NodeDiscoverer = d
+	}
+}
+
+// WithRetries retry count on other nodes in case of error
+func WithRetries(n int) ClusterOption {
+	return func(o *ClusterOptions) {
+		o.Retries = n
+	}
+}
+
+// WithClusterContext pass context.Context to cluster options and used for checks
+func WithClusterContext(ctx context.Context) ClusterOption {
+	return func(o *ClusterOptions) {
+		o.Context = ctx
+	}
+}
+
+// WithClusterOptions pass hasql.ClusterOpt
+func WithClusterOptions(opts ...hasql.ClusterOpt[Querier]) ClusterOption {
+	return func(o *ClusterOptions) {
+		o.Options = append(o.Options, opts...)
+	}
+}
+
+// WithClusterNodeStateCriterion pass default hasql.NodeStateCriterion
+func WithClusterNodeStateCriterion(c hasql.NodeStateCriterion) ClusterOption {
+	return func(o *ClusterOptions) {
+		o.NodeStateCriterion = c
+	}
+}
+
+type ClusterNode struct {
+	Name     string
+	DB       Querier
+	Priority int32
+}
+
+// WithClusterNodes create cluster with static NodeDiscoverer
+func WithClusterNodes(cns ...ClusterNode) ClusterOption {
+	return func(o *ClusterOptions) {
+		nodes := make([]*hasql.Node[Querier], 0, len(cns))
+		if o.NodePriority == nil {
+			o.NodePriority = make(map[string]int32, len(cns))
+		}
+		for _, cn := range cns {
+			nodes = append(nodes, hasql.NewNode(cn.Name, cn.DB))
+			if cn.Priority == 0 {
+				cn.Priority = math.MaxInt32
+			}
+			o.NodePriority[cn.Name] = cn.Priority
+		}
+		o.NodeDiscoverer = hasql.NewStaticNodeDiscoverer(nodes...)
+	}
+}
+
+type nodeStateCriterionKey struct{}
+
+// NodeStateCriterion inject hasql.NodeStateCriterion to context
+func NodeStateCriterion(ctx context.Context, c hasql.NodeStateCriterion) context.Context {
+	return context.WithValue(ctx, nodeStateCriterionKey{}, c)
+}
+
+func (c *Cluster) getNodeStateCriterion(ctx context.Context) hasql.NodeStateCriterion {
+	if v, ok := ctx.Value(nodeStateCriterionKey{}).(hasql.NodeStateCriterion); ok {
+		return v
+	}
+	return c.options.NodeStateCriterion
+}

cluster/hasql/picker.go

@@ -0,0 +1,113 @@
+package sql
+
+import (
+	"fmt"
+	"math"
+	"time"
+
+	"golang.yandex/hasql/v2"
+)
+
+// compile time guard
+var _ hasql.NodePicker[Querier] = (*CustomPicker[Querier])(nil)
+
+// CustomPickerOptions holds options to pick nodes
+type CustomPickerOptions struct {
+	MaxLag   int
+	Priority map[string]int32
+	Retries  int
+}
+
+// CustomPickerOption func apply option to CustomPickerOptions
+type CustomPickerOption func(*CustomPickerOptions)
+
+// CustomPickerMaxLag specifies max lag for which node can be used
+func CustomPickerMaxLag(n int) CustomPickerOption {
+	return func(o *CustomPickerOptions) {
+		o.MaxLag = n
+	}
+}
+
+// NewCustomPicker creates new node picker
+func NewCustomPicker[T Querier](opts ...CustomPickerOption) *CustomPicker[Querier] {
+	options := CustomPickerOptions{}
+	for _, o := range opts {
+		o(&options)
+	}
+	return &CustomPicker[Querier]{opts: options}
+}
+
+// CustomPicker holds node picker options
+type CustomPicker[T Querier] struct {
+	opts CustomPickerOptions
+}
+
+// PickNode used to return specific node
+func (p *CustomPicker[T]) PickNode(cnodes []hasql.CheckedNode[T]) hasql.CheckedNode[T] {
+	for _, n := range cnodes {
+		fmt.Printf("node %s\n", n.Node.String())
+	}
+	return cnodes[0]
+}
+
+func (p *CustomPicker[T]) getPriority(nodeName string) int32 {
+	if prio, ok := p.opts.Priority[nodeName]; ok {
+		return prio
+	}
+	return math.MaxInt32 // Default to lowest priority
+}
+
+// CompareNodes used to sort nodes
+func (p *CustomPicker[T]) CompareNodes(a, b hasql.CheckedNode[T]) int {
+	// Get replication lag values
+	aLag := a.Info.(interface{ ReplicationLag() int }).ReplicationLag()
+	bLag := b.Info.(interface{ ReplicationLag() int }).ReplicationLag()
+
+	// First check that lag lower then MaxLag
+	if aLag > p.opts.MaxLag && bLag > p.opts.MaxLag {
+		return 0 // both are equal
+	}
+
+	// If one node exceeds MaxLag and the other doesn't, prefer the one that doesn't
+	if aLag > p.opts.MaxLag {
+		return 1 // b is better
+	}
+	if bLag > p.opts.MaxLag {
+		return -1 // a is better
+	}
+
+	// Get node priorities
+	aPrio := p.getPriority(a.Node.String())
+	bPrio := p.getPriority(b.Node.String())
+
+	// if both priority equals
+	if aPrio == bPrio {
+		// First compare by replication lag
+		if aLag < bLag {
+			return -1
+		}
+		if aLag > bLag {
+			return 1
+		}
+		// If replication lag is equal, compare by latency
+		aLatency := a.Info.(interface{ Latency() time.Duration }).Latency()
+		bLatency := b.Info.(interface{ Latency() time.Duration }).Latency()
+
+		if aLatency < bLatency {
+			return -1
+		}
+		if aLatency > bLatency {
+			return 1
+		}
+
+		// If lag and latency is equal
+		return 0
+	}
+
+	// If priorities are different, prefer the node with lower priority value
+	if aPrio < bPrio {
+		return -1
+	}
+
+	return 1
+}

cluster/sql/cluster.go

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

cluster/sql/cluster_test.go

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

codec/codec.go

@@ -3,6 +3,8 @@ package codec
 
 import (
 	"errors"
+
+	"gopkg.in/yaml.v3"
 )
 
 var (
@@ -54,3 +56,22 @@ func (m *RawMessage) UnmarshalJSON(data []byte) error {
 	*m = append((*m)[0:0], data...)
 	return nil
 }
+
+// MarshalYAML returns m as the JSON encoding of m.
+func (m *RawMessage) MarshalYAML() ([]byte, error) {
+	if m == nil {
+		return []byte("null"), nil
+	} else if len(*m) == 0 {
+		return []byte("null"), nil
+	}
+	return *m, nil
+}
+
+// UnmarshalYAML sets *m to a copy of data.
+func (m *RawMessage) UnmarshalYAML(n *yaml.Node) error {
+	if m == nil {
+		return errors.New("RawMessage UnmarshalYAML on nil pointer")
+	}
+	*m = append((*m)[0:0], []byte(n.Value)...)
+	return nil
+}

codec/context.go

@@ -15,6 +15,15 @@ func FromContext(ctx context.Context) (Codec, bool) {
 	return c, ok
 }
 
+// MustContext returns codec from context
+func MustContext(ctx context.Context) Codec {
+	c, ok := FromContext(ctx)
+	if !ok {
+		panic("missing codec")
+	}
+	return c
+}
+
 // NewContext put codec in context
 func NewContext(ctx context.Context, c Codec) context.Context {
 	if ctx == nil {

codec/frame.go

@@ -1,5 +1,7 @@
 package codec
 
+import "gopkg.in/yaml.v3"
+
 // Frame gives us the ability to define raw data to send over the pipes
 type Frame struct {
 	Data []byte
@@ -20,6 +22,17 @@ func (m *Frame) UnmarshalJSON(data []byte) error {
 	return m.Unmarshal(data)
 }
 
+// MarshalYAML returns frame data
+func (m *Frame) MarshalYAML() ([]byte, error) {
+	return m.Marshal()
+}
+
+// UnmarshalYAML set frame data
+func (m *Frame) UnmarshalYAML(n *yaml.Node) error {
+	m.Data = []byte(n.Value)
+	return nil
+}
+
 // ProtoMessage noop func
 func (m *Frame) ProtoMessage() {}
 

config/config.go

@@ -4,7 +4,6 @@ package config
 import (
 	"context"
 	"errors"
-	"fmt"
 	"reflect"
 	"time"
 )
@@ -14,7 +13,7 @@ type Validator interface {
 }
 
 // DefaultConfig default config
-var DefaultConfig Config = NewConfig()
+var DefaultConfig = NewConfig()
 
 // DefaultWatcherMinInterval default min interval for poll changes
 var DefaultWatcherMinInterval = 5 * time.Second
@@ -139,7 +138,7 @@ var (
 				return nil
 			}
 			if err := fn(ctx, c); err != nil {
-				c.Options().Logger.Error(ctx, fmt.Sprintf("%s BeforeLoad error", c.String()), err)
+				c.Options().Logger.Error(ctx, c.String()+" BeforeLoad error", err)
 				if !c.Options().AllowFail {
 					return err
 				}
@@ -154,7 +153,7 @@ var (
 				return nil
 			}
 			if err := fn(ctx, c); err != nil {
-				c.Options().Logger.Error(ctx, fmt.Sprintf("%s AfterLoad error", c.String()), err)
+				c.Options().Logger.Error(ctx, c.String()+" AfterLoad error", err)
 				if !c.Options().AllowFail {
 					return err
 				}
@@ -169,7 +168,7 @@ var (
 				return nil
 			}
 			if err := fn(ctx, c); err != nil {
-				c.Options().Logger.Error(ctx, fmt.Sprintf("%s BeforeSave error", c.String()), err)
+				c.Options().Logger.Error(ctx, c.String()+" BeforeSave error", err)
 				if !c.Options().AllowFail {
 					return err
 				}
@@ -184,7 +183,7 @@ var (
 				return nil
 			}
 			if err := fn(ctx, c); err != nil {
-				c.Options().Logger.Error(ctx, fmt.Sprintf("%s AfterSave error", c.String()), err)
+				c.Options().Logger.Error(ctx, c.String()+" AfterSave error", err)
 				if !c.Options().AllowFail {
 					return err
 				}
@@ -199,7 +198,7 @@ var (
 				return nil
 			}
 			if err := fn(ctx, c); err != nil {
-				c.Options().Logger.Error(ctx, fmt.Sprintf("%s BeforeInit error", c.String()), err)
+				c.Options().Logger.Error(ctx, c.String()+" BeforeInit error", err)
 				if !c.Options().AllowFail {
 					return err
 				}
@@ -214,7 +213,7 @@ var (
 				return nil
 			}
 			if err := fn(ctx, c); err != nil {
-				c.Options().Logger.Error(ctx, fmt.Sprintf("%s AfterInit error", c.String(), err), err)
+				c.Options().Logger.Error(ctx, c.String()+" AfterInit error", err)
 				if !c.Options().AllowFail {
 					return err
 				}

config/context.go

@@ -15,6 +15,15 @@ func FromContext(ctx context.Context) (Config, bool) {
 	return c, ok
 }
 
+// MustContext returns store from context
+func MustContext(ctx context.Context) Config {
+	c, ok := FromContext(ctx)
+	if !ok {
+		panic("missing config")
+	}
+	return c
+}
+
 // NewContext put store in context
 func NewContext(ctx context.Context, c Config) context.Context {
 	if ctx == nil {

config/default.go

@@ -37,7 +37,7 @@ func (c *defaultConfig) Init(opts ...Option) error {
 	c.funcLoad = c.fnLoad
 	c.funcSave = c.fnSave
 
-	c.opts.Hooks.EachNext(func(hook options.Hook) {
+	c.opts.Hooks.EachPrev(func(hook options.Hook) {
 		switch h := hook.(type) {
 		case HookLoad:
 			c.funcLoad = h(c.funcLoad)

config/default_test.go

@@ -3,24 +3,26 @@ package config_test
 import (
 	"context"
 	"fmt"
+	"reflect"
 	"testing"
 	"time"
 
 	"go.unistack.org/micro/v3/config"
-	mid "go.unistack.org/micro/v3/util/id"
 	mtime "go.unistack.org/micro/v3/util/time"
 )
 
 type cfg struct {
-	StringValue    string `default:"string_value"`
+	MapValue    map[string]bool `default:"key1=true,key2=false"`
-	IgnoreValue    string `json:"-"`
+	StructValue *cfgStructValue
-	StructValue    *cfgStructValue
+
-	IntValue       int             `default:"99"`
+	StringValue string `default:"string_value"`
-	DurationValue  time.Duration   `default:"10s"`
+	IgnoreValue string `json:"-"`
-	MDurationValue mtime.Duration  `default:"10s"`
+	UUIDValue   string `default:"micro:generate uuid"`
-	MapValue       map[string]bool `default:"key1=true,key2=false"`
+	IDValue     string `default:"micro:generate id"`
-	UUIDValue      string          `default:"micro:generate uuid"`
+
-	IDValue        string          `default:"micro:generate id"`
+	DurationValue  time.Duration  `default:"10s"`
+	MDurationValue mtime.Duration `default:"10s"`
+	IntValue       int            `default:"99"`
 }
 
 type cfgStructValue struct {
@@ -112,8 +114,6 @@ func TestDefault(t *testing.T) {
 
 	if conf.IDValue == "" {
 		t.Fatalf("id value empty")
-	} else if len(conf.IDValue) != mid.DefaultSize {
-		t.Fatalf("id value invalid: %s", conf.IDValue)
 	}
 	_ = conf
 	// t.Logf("%#+v\n", conf)
@@ -134,3 +134,13 @@ func TestValidate(t *testing.T) {
 		t.Fatal(err)
 	}
 }
+
+func Test_SizeOf(t *testing.T) {
+	st := cfg{}
+
+	tVal := reflect.TypeOf(st)
+	for i := 0; i < tVal.NumField(); i++ {
+		field := tVal.Field(i)
+		fmt.Printf("Field: %s, Offset: %d, Size: %d\n", field.Name, field.Offset, field.Type.Size())
+	}
+}

config/options.go

@@ -41,14 +41,16 @@ type Options struct {
 	BeforeInit []func(context.Context, Config) error
 	// AfterInit contains slice of funcs that runs after Init
 	AfterInit []func(context.Context, Config) error
-	// AllowFail flag to allow fail in config source
+
-	AllowFail bool
 	// SkipLoad runs only if condition returns true
 	SkipLoad func(context.Context, Config) bool
 	// SkipSave runs only if condition returns true
 	SkipSave func(context.Context, Config) bool
 	// Hooks can be run before/after config Save/Load
 	Hooks options.Hooks
+
+	// AllowFail flag to allow fail in config source
+	AllowFail bool
 }
 
 // Option function signature
@@ -278,10 +280,10 @@ func WatchCoalesce(b bool) WatchOption {
 }
 
 // WatchInterval specifies min and max time.Duration for pulling changes
-func WatchInterval(min, max time.Duration) WatchOption {
+func WatchInterval(minTime, maxTime time.Duration) WatchOption {
 	return func(o *WatchOptions) {
-		o.MinInterval = min
+		o.MinInterval = minTime
-		o.MaxInterval = max
+		o.MaxInterval = maxTime
 	}
 }
 

errors/errors_test.go

@@ -2,7 +2,7 @@ package errors
 
 import (
 	"encoding/json"
-	er "errors"
+	"errors"
 	"fmt"
 	"net/http"
 	"testing"
@@ -26,7 +26,7 @@ func TestMarshalJSON(t *testing.T) {
 func TestEmpty(t *testing.T) {
 	msg := "test"
 	var err *Error
-	err = FromError(fmt.Errorf(msg))
+	err = FromError(errors.New(msg))
 	if err.Detail != msg {
 		t.Fatalf("invalid error %v", err)
 	}
@@ -42,7 +42,7 @@ func TestFromError(t *testing.T) {
 	if merr.ID != "go.micro.test" || merr.Code != 404 {
 		t.Fatalf("invalid conversation %v != %v", err, merr)
 	}
-	err = er.New(err.Error())
+	err = errors.New(err.Error())
 	merr = FromError(err)
 	if merr.ID != "go.micro.test" || merr.Code != 404 {
 		t.Fatalf("invalid conversation %v != %v", err, merr)
@@ -57,7 +57,7 @@ func TestEqual(t *testing.T) {
 		t.Fatal("errors must be equal")
 	}
 
-	err3 := er.New("my test err")
+	err3 := errors.New("my test err")
 	if Equal(err1, err3) {
 		t.Fatal("errors must be not equal")
 	}

flow/context.go

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

fsm/default.go

@@ -32,7 +32,7 @@ type fsm struct {
 
 // NewFSM creates a new finite state machine having the specified initial state
 // with specified options
-func NewFSM(opts ...Option) *fsm {
+func NewFSM(opts ...Option) FSM {
 	return &fsm{
 		statesMap: map[string]StateFunc{},
 		opts:      NewOptions(opts...),

go.mod

@@ -1,32 +1,44 @@
 module go.unistack.org/micro/v3
 
-go 1.22
+go 1.24.0
 
 require (
-	dario.cat/mergo v1.0.0
+	dario.cat/mergo v1.0.1
-	github.com/DATA-DOG/go-sqlmock v1.5.0
+	github.com/DATA-DOG/go-sqlmock v1.5.2
 	github.com/KimMachineGun/automemlimit v0.6.1
-	github.com/google/uuid v1.3.0
+	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 v0.3.0
+	golang.org/x/sync v0.10.0
-	google.golang.org/grpc v1.57.0
+	golang.yandex/hasql/v2 v2.1.0
-	google.golang.org/protobuf v1.33.0
+	google.golang.org/grpc v1.69.2
+	google.golang.org/protobuf v1.36.1
+	gopkg.in/yaml.v3 v3.0.1
 )
 
 require (
-	github.com/cilium/ebpf v0.9.1 // indirect
+	github.com/cilium/ebpf v0.16.0 // indirect
-	github.com/containerd/cgroups/v3 v3.0.1 // indirect
+	github.com/containerd/cgroups/v3 v3.0.4 // indirect
-	github.com/coreos/go-systemd/v22 v22.3.2 // indirect
+	github.com/containerd/log v0.1.0 // indirect
-	github.com/docker/go-units v0.4.0 // indirect
+	github.com/coreos/go-systemd/v22 v22.5.0 // indirect
-	github.com/godbus/dbus/v5 v5.0.4 // indirect
+	github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc // indirect
-	github.com/golang/protobuf v1.5.3 // indirect
+	github.com/docker/go-units v0.5.0 // indirect
-	github.com/opencontainers/runtime-spec v1.0.2 // indirect
+	github.com/godbus/dbus/v5 v5.1.0 // indirect
+	github.com/moby/sys/userns v0.1.0 // indirect
+	github.com/opencontainers/runtime-spec v1.2.0 // indirect
 	github.com/pbnjay/memory v0.0.0-20210728143218-7b4eea64cf58 // indirect
-	github.com/sirupsen/logrus v1.8.1 // indirect
+	github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2 // indirect
-	golang.org/x/net v0.14.0 // indirect
+	github.com/rogpeppe/go-internal v1.13.1 // indirect
-	golang.org/x/sys v0.11.0 // indirect
+	github.com/sirupsen/logrus v1.9.3 // indirect
-	google.golang.org/genproto/googleapis/rpc v0.0.0-20230526203410-71b5a4ffd15e // indirect
+	go.uber.org/goleak v1.3.0 // indirect
+	golang.org/x/exp v0.0.0-20241210194714-1829a127f884 // indirect
+	golang.org/x/net v0.33.0 // indirect
+	golang.org/x/sys v0.28.0 // indirect
+	google.golang.org/genproto/googleapis/rpc v0.0.0-20241216192217-9240e9c98484 // indirect
+	gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c // indirect
 )

go.sum

@@ -1,78 +1,105 @@
-dario.cat/mergo v1.0.0 h1:AGCNq9Evsj31mOgNPcLyXc+4PNABt905YmuqPYYpBWk=
+dario.cat/mergo v1.0.1 h1:Ra4+bf83h2ztPIQYNP99R6m+Y7KfnARDfID+a+vLl4s=
-dario.cat/mergo v1.0.0/go.mod h1:uNxQE+84aUszobStD9th8a29P2fMDhsBdgRYvZOxGmk=
+dario.cat/mergo v1.0.1/go.mod h1:uNxQE+84aUszobStD9th8a29P2fMDhsBdgRYvZOxGmk=
-github.com/DATA-DOG/go-sqlmock v1.5.0 h1:Shsta01QNfFxHCfpW6YH2STWB0MudeXXEWMr20OEh60=
+github.com/DATA-DOG/go-sqlmock v1.5.2 h1:OcvFkGmslmlZibjAjaHm3L//6LiuBgolP7OputlJIzU=
-github.com/DATA-DOG/go-sqlmock v1.5.0/go.mod h1:f/Ixk793poVmq4qj/V1dPUg2JEAKC73Q5eFN3EC/SaM=
+github.com/DATA-DOG/go-sqlmock v1.5.2/go.mod h1:88MAG/4G7SMwSE3CeA0ZKzrT5CiOU3OJ+JlNzwDqpNU=
 github.com/KimMachineGun/automemlimit v0.6.1 h1:ILa9j1onAAMadBsyyUJv5cack8Y1WT26yLj/V+ulKp8=
 github.com/KimMachineGun/automemlimit v0.6.1/go.mod h1:T7xYht7B8r6AG/AqFcUdc7fzd2bIdBKmepfP2S1svPY=
-github.com/cilium/ebpf v0.9.1 h1:64sn2K3UKw8NbP/blsixRpF3nXuyhz/VjRlRzvlBRu4=
+github.com/ash3in/uuidv8 v1.2.0 h1:2oogGdtCPwaVtyvPPGin4TfZLtOGE5F+W++E880G6SI=
-github.com/cilium/ebpf v0.9.1/go.mod h1:+OhNOIXx/Fnu1IE8bJz2dzOA+VSfyTfdNUVdlQnxUFY=
+github.com/ash3in/uuidv8 v1.2.0/go.mod h1:BnU0wJBxnzdEKmVg4xckBkD+VZuecTFTUP3M0dWgyY4=
-github.com/containerd/cgroups/v3 v3.0.1 h1:4hfGvu8rfGIwVIDd+nLzn/B9ZXx4BcCjzt5ToenJRaE=
+github.com/cilium/ebpf v0.16.0 h1:+BiEnHL6Z7lXnlGUsXQPPAE7+kenAd4ES8MQ5min0Ok=
-github.com/containerd/cgroups/v3 v3.0.1/go.mod h1:/vtwk1VXrtoa5AaZLkypuOJgA/6DyPMZHJPGQNtlHnw=
+github.com/cilium/ebpf v0.16.0/go.mod h1:L7u2Blt2jMM/vLAVgjxluxtBKlz3/GWjB0dMOEngfwE=
-github.com/coreos/go-systemd/v22 v22.3.2 h1:D9/bQk5vlXQFZ6Kwuu6zaiXJ9oTPe68++AzAJc1DzSI=
+github.com/containerd/cgroups/v3 v3.0.4 h1:2fs7l3P0Qxb1nKWuJNFiwhp2CqiKzho71DQkDrHJIo4=
-github.com/coreos/go-systemd/v22 v22.3.2/go.mod h1:Y58oyj3AT4RCenI/lSvhwexgC+NSVTIJ3seZv2GcEnc=
+github.com/containerd/cgroups/v3 v3.0.4/go.mod h1:SA5DLYnXO8pTGYiAHXz94qvLQTKfVM5GEVisn4jpins=
-github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/containerd/log v0.1.0 h1:TCJt7ioM2cr/tfR8GPbGf9/VRAX8D2B4PjzCpfX540I=
+github.com/containerd/log v0.1.0/go.mod h1:VRRf09a7mHDIRezVKTRCrOq78v577GXq3bSa3EhrzVo=
+github.com/coreos/go-systemd/v22 v22.5.0 h1:RrqgGjYQKalulkV8NGVIfkXQf6YYmOyiJKk8iXXhfZs=
+github.com/coreos/go-systemd/v22 v22.5.0/go.mod h1:Y58oyj3AT4RCenI/lSvhwexgC+NSVTIJ3seZv2GcEnc=
+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
-github.com/docker/go-units v0.4.0 h1:3uh0PgVws3nIA0Q+MwDC8yjEPf9zjRfZZWXZYDct3Tw=
+github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc h1:U9qPSI2PIWSS1VwoXQT9A3Wy9MM3WgvqSxFWenqJduM=
-github.com/docker/go-units v0.4.0/go.mod h1:fgPhTUdO+D/Jk86RDLlptpiXQzgHJF7gydDDbaIK4Dk=
+github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
-github.com/frankban/quicktest v1.14.0 h1:+cqqvzZV87b4adx/5ayVOaYZ2CrvM4ejQvUdBzPPUss=
+github.com/docker/go-units v0.5.0 h1:69rxXcBk27SvSaaxTtLh/8llcHD8vYHT7WSdRZ/jvr4=
-github.com/frankban/quicktest v1.14.0/go.mod h1:NeW+ay9A/U67EYXNFA1nPE8e/tnQv/09mUdL/ijj8og=
+github.com/docker/go-units v0.5.0/go.mod h1:fgPhTUdO+D/Jk86RDLlptpiXQzgHJF7gydDDbaIK4Dk=
-github.com/godbus/dbus/v5 v5.0.4 h1:9349emZab16e7zQvpmsbtjc18ykshndd8y2PG3sgJbA=
+github.com/go-quicktest/qt v1.101.0 h1:O1K29Txy5P2OK0dGo59b7b0LR6wKfIhttaAhHUyn7eI=
+github.com/go-quicktest/qt v1.101.0/go.mod h1:14Bz/f7NwaXPtdYEgzsx46kqSxVwTbzVZsDC26tQJow=
 github.com/godbus/dbus/v5 v5.0.4/go.mod h1:xhWf0FNVPg57R7Z0UbKHbJfkEywrmjJnf7w5xrFpKfA=
-github.com/golang/protobuf v1.5.0/go.mod h1:FsONVRAS9T7sI+LIUmWTfcYkHO4aIWwzhcaSAoJOfIk=
+github.com/godbus/dbus/v5 v5.1.0 h1:4KLkAxT3aOY8Li4FRJe/KvhoNFFxo0m6fNuFUO8QJUk=
-github.com/golang/protobuf v1.5.3 h1:KhyjKVUg7Usr/dYsdSqoFveMYd5ko72D+zANwlG1mmg=
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-github.com/golang/protobuf v1.5.3/go.mod h1:XVQd3VNwM+JqD3oG2Ue2ip4fOMUkwXdXDdiuN0vRsmY=
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-github.com/google/go-cmp v0.5.5/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
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-github.com/google/go-cmp v0.5.9 h1:O2Tfq5qg4qc4AmwVlvv0oLiVAGB7enBSJ2x2DqQFi38=
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-github.com/google/go-cmp v0.5.9/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
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-github.com/google/uuid v1.3.0 h1:t6JiXgmwXMjEs8VusXIJk2BXHsn+wx8BZdTaoZ5fu7I=
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-github.com/google/uuid v1.3.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
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-github.com/kr/pretty v0.3.0 h1:WgNl7dwNpEZ6jJ9k1snq4pZsg7DOEN8hP9Xw0Tsjwk0=
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-github.com/kr/pretty v0.3.0/go.mod h1:640gp4NfQd8pI5XOwp5fnNeVWj67G7CFk/SaSQn7NBk=
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+github.com/jsimonetti/rtnetlink/v2 v2.0.1 h1:xda7qaHDSVOsADNouv7ukSuicKZO7GgVUCXxpaIEIlM=
+github.com/jsimonetti/rtnetlink/v2 v2.0.1/go.mod h1:7MoNYNbb3UaDHtF8udiJo/RH6VsTKP1pqKLUTVCvToE=
+github.com/kisielk/sqlstruct v0.0.0-20201105191214-5f3e10d3ab46/go.mod h1:yyMNCyc/Ib3bDTKd379tNMpB/7/H5TjM2Y9QJ5THLbE=
+github.com/kr/pretty v0.2.1/go.mod h1:ipq/a2n7PKx3OHsz4KJII5eveXtPO4qwEXGdVfWzfnI=
+github.com/kr/pretty v0.3.1 h1:flRD4NNwYAUpkphVc1HcthR4KEIFJ65n8Mw5qdRn3LE=
+github.com/kr/pretty v0.3.1/go.mod h1:hoEshYVHaxMs3cyo3Yncou5ZscifuDolrwPKZanG3xk=
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hooks/metadata/metadata.go

@@ -0,0 +1,76 @@
+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

@@ -0,0 +1,94 @@
+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

@@ -0,0 +1,139 @@
+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

@@ -0,0 +1,33 @@
+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

@@ -0,0 +1,51 @@
+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

@@ -0,0 +1,467 @@
+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

@@ -0,0 +1,94 @@
+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

@@ -0,0 +1,165 @@
+//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

@@ -0,0 +1,172 @@
+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

@@ -0,0 +1,41 @@
+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

@@ -0,0 +1,287 @@
+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

@@ -0,0 +1,63 @@
+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

@@ -0,0 +1,19 @@
+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

@@ -0,0 +1,194 @@
+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/context.go

@@ -4,17 +4,6 @@ import "context"
 
 type loggerKey struct{}
 
-// MustContext returns logger from passed context or DefaultLogger if empty
-func MustContext(ctx context.Context) Logger {
-	if ctx == nil {
-		return DefaultLogger
-	}
-	if l, ok := ctx.Value(loggerKey{}).(Logger); ok && l != nil {
-		return l
-	}
-	return DefaultLogger
-}
-
 // FromContext returns logger from passed context
 func FromContext(ctx context.Context) (Logger, bool) {
 	if ctx == nil {
@@ -24,6 +13,15 @@ func FromContext(ctx context.Context) (Logger, bool) {
 	return l, ok
 }
 
+// MustContext returns logger from passed context or DefaultLogger if empty
+func MustContext(ctx context.Context) Logger {
+	l, ok := FromContext(ctx)
+	if !ok {
+		panic("missing logger")
+	}
+	return l
+}
+
 // NewContext stores logger into passed context
 func NewContext(ctx context.Context, l Logger) context.Context {
 	if ctx == nil {

logger/level.go

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

logger/logger.go

@@ -11,7 +11,7 @@ var DefaultContextAttrFuncs []ContextAttrFunc
 
 var (
 	// DefaultLogger variable
-	DefaultLogger Logger = NewLogger()
+	DefaultLogger = NewLogger()
 	// DefaultLevel used by logger
 	DefaultLevel = InfoLevel
 )

logger/options.go

@@ -5,6 +5,7 @@ import (
 	"io"
 	"log/slog"
 	"os"
+	"slices"
 	"time"
 
 	"go.unistack.org/micro/v3/meter"
@@ -15,18 +16,6 @@ type Option func(*Options)
 
 // Options holds logger options
 type Options struct {
-	// Out holds the output writer
-	Out io.Writer
-	// Context holds exernal options
-	Context context.Context
-	// Name holds the logger name
-	Name string
-	// Fields holds additional metadata
-	Fields []interface{}
-	// callerSkipCount number of frmaes to skip
-	CallerSkipCount int
-	// ContextAttrFuncs contains funcs that executed before log func on context
-	ContextAttrFuncs []ContextAttrFunc
 	// TimeKey is the key used for the time of the log call
 	TimeKey string
 	// LevelKey is the key used for the level of the log call
@@ -39,16 +28,36 @@ type Options struct {
 	SourceKey string
 	// StacktraceKey is the key used for the stacktrace
 	StacktraceKey string
-	// AddStacktrace controls writing of stacktaces on error
+	// Name holds the logger name
-	AddStacktrace bool
+	Name string
-	// AddSource enabled writing source file and position in log
+	// Out holds the output writer
-	AddSource bool
+	Out io.Writer
-	// The logging level the logger should log
+	// Context holds exernal options
-	Level Level
+	Context context.Context
-	// TimeFunc used to obtain current time
-	TimeFunc func() time.Time
 	// Meter used to count logs for specific level
 	Meter meter.Meter
+	// TimeFunc used to obtain current time
+	TimeFunc func() time.Time
+	// Fields holds additional metadata
+	Fields []interface{}
+	// ContextAttrFuncs contains funcs that executed before log func on context
+	ContextAttrFuncs []ContextAttrFunc
+	// callerSkipCount number of frmaes to skip
+	CallerSkipCount int
+	// The logging level the logger should log
+	Level Level
+	// AddSource enabled writing source file and position in log
+	AddSource bool
+	// AddStacktrace controls writing of stacktaces on error
+	AddStacktrace bool
+	// DedupKeys deduplicate keys in log output
+	DedupKeys bool
+	// FatalFinalizers runs in order in [logger.Fatal] method
+	FatalFinalizers []func(context.Context)
+}
+
+var DefaultFatalFinalizer = func(ctx context.Context) {
+	os.Exit(1)
 }
 
 // NewOptions creates new options struct
@@ -62,6 +71,7 @@ func NewOptions(opts ...Option) Options {
 		AddSource:        true,
 		TimeFunc:         time.Now,
 		Meter:            meter.DefaultMeter,
+		FatalFinalizers:  []func(context.Context){DefaultFatalFinalizer},
 	}
 
 	WithMicroKeys()(&options)
@@ -73,6 +83,13 @@ func NewOptions(opts ...Option) Options {
 	return options
 }
 
+// WithFatalFinalizers set logger.Fatal finalizers
+func WithFatalFinalizers(fncs ...func(context.Context)) Option {
+	return func(o *Options) {
+		o.FatalFinalizers = fncs
+	}
+}
+
 // WithContextAttrFuncs appends default funcs for the context attrs filler
 func WithContextAttrFuncs(fncs ...ContextAttrFunc) Option {
 	return func(o *Options) {
@@ -80,10 +97,33 @@ func WithContextAttrFuncs(fncs ...ContextAttrFunc) Option {
 	}
 }
 
+// WithDedupKeys dont log duplicate keys
+func WithDedupKeys(b bool) Option {
+	return func(o *Options) {
+		o.DedupKeys = b
+	}
+}
+
 // WithAddFields add fields for the logger
 func WithAddFields(fields ...interface{}) Option {
 	return func(o *Options) {
-		o.Fields = append(o.Fields, fields...)
+		if o.DedupKeys {
+			for i := 0; i < len(o.Fields); i += 2 {
+				for j := 0; j < len(fields); j += 2 {
+					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)
+					}
+				}
+			}
+			if len(fields) > 0 {
+				o.Fields = append(o.Fields, fields...)
+			}
+		} else {
+			o.Fields = append(o.Fields, fields...)
+		}
 	}
 }
 
@@ -153,8 +193,8 @@ func WithTimeFunc(fn func() time.Time) Option {
 func WithZapKeys() Option {
 	return func(o *Options) {
 		o.TimeKey = "@timestamp"
-		o.LevelKey = "level"
+		o.LevelKey = slog.LevelKey
-		o.MessageKey = "msg"
+		o.MessageKey = slog.MessageKey
 		o.SourceKey = "caller"
 		o.StacktraceKey = "stacktrace"
 		o.ErrorKey = "error"
@@ -163,8 +203,8 @@ func WithZapKeys() Option {
 
 func WithZerologKeys() Option {
 	return func(o *Options) {
-		o.TimeKey = "time"
+		o.TimeKey = slog.TimeKey
-		o.LevelKey = "level"
+		o.LevelKey = slog.LevelKey
 		o.MessageKey = "message"
 		o.SourceKey = "caller"
 		o.StacktraceKey = "stacktrace"
@@ -186,8 +226,8 @@ func WithSlogKeys() Option {
 func WithMicroKeys() Option {
 	return func(o *Options) {
 		o.TimeKey = "timestamp"
-		o.LevelKey = "level"
+		o.LevelKey = slog.LevelKey
-		o.MessageKey = "msg"
+		o.MessageKey = slog.MessageKey
 		o.SourceKey = "caller"
 		o.StacktraceKey = "stacktrace"
 		o.ErrorKey = "error"

logger/slog/slog.go

@@ -2,8 +2,9 @@ package slog
 
 import (
 	"context"
+	"io"
 	"log/slog"
-	"os"
+	"reflect"
 	"regexp"
 	"runtime"
 	"strconv"
@@ -19,6 +20,7 @@ const (
 	badKey = "!BADKEY"
 	// defaultCallerSkipCount used by logger
 	defaultCallerSkipCount = 3
+	timeFormat             = "2006-01-02T15:04:05.000000000Z07:00"
 )
 
 var reTrace = regexp.MustCompile(`.*/slog/logger\.go.*\n`)
@@ -30,6 +32,7 @@ var (
 	warnValue  = slog.StringValue("warn")
 	errorValue = slog.StringValue("error")
 	fatalValue = slog.StringValue("fatal")
+	noneValue  = slog.StringValue("none")
 )
 
 type wrapper struct {
@@ -46,11 +49,11 @@ func (h *wrapper) Handle(ctx context.Context, rec slog.Record) error {
 }
 
 func (h *wrapper) WithAttrs(attrs []slog.Attr) slog.Handler {
-	return h.WithAttrs(attrs)
+	return h.h.WithAttrs(attrs)
 }
 
 func (h *wrapper) WithGroup(name string) slog.Handler {
-	return h.WithGroup(name)
+	return h.h.WithGroup(name)
 }
 
 func (s *slogLogger) renameAttr(_ []string, a slog.Attr) slog.Attr {
@@ -61,6 +64,7 @@ func (s *slogLogger) renameAttr(_ []string, a slog.Attr) slog.Attr {
 		a.Key = s.opts.SourceKey
 	case slog.TimeKey:
 		a.Key = s.opts.TimeKey
+		a.Value = slog.StringValue(a.Value.Time().Format(timeFormat))
 	case slog.MessageKey:
 		a.Key = s.opts.MessageKey
 	case slog.LevelKey:
@@ -80,6 +84,8 @@ func (s *slogLogger) renameAttr(_ []string, a slog.Attr) slog.Attr {
 			a.Value = errorValue
 		case lvl >= logger.FatalLevel:
 			a.Value = fatalValue
+		case lvl >= logger.NoneLevel:
+			a.Value = noneValue
 		default:
 			a.Value = infoValue
 		}
@@ -89,7 +95,6 @@ func (s *slogLogger) renameAttr(_ []string, a slog.Attr) slog.Attr {
 }
 
 type slogLogger struct {
-	leveler *slog.LevelVar
 	handler *wrapper
 	opts    logger.Options
 	mu      sync.RWMutex
@@ -142,6 +147,7 @@ func (s *slogLogger) Fields(fields ...interface{}) logger.Logger {
 	s.mu.RUnlock()
 
 	l := &slogLogger{opts: options}
+	logger.WithAddFields(fields...)(&l.opts)
 
 	if len(options.ContextAttrFuncs) == 0 {
 		options.ContextAttrFuncs = logger.DefaultContextAttrFuncs
@@ -172,7 +178,29 @@ func (s *slogLogger) Init(opts ...logger.Option) error {
 	}
 
 	attrs, _ := s.argsAttrs(s.opts.Fields)
-	s.handler = &wrapper{h: slog.NewJSONHandler(s.opts.Out, handleOpt).WithAttrs(attrs)}
+
+	var h slog.Handler
+	if s.opts.Context != nil {
+		if v, ok := s.opts.Context.Value(handlerKey{}).(slog.Handler); ok && v != nil {
+			h = v
+		}
+
+		if fn := s.opts.Context.Value(handlerFnKey{}); fn != nil {
+			if rfn := reflect.ValueOf(fn); rfn.Kind() == reflect.Func {
+				if ret := rfn.Call([]reflect.Value{reflect.ValueOf(s.opts.Out), reflect.ValueOf(handleOpt)}); len(ret) == 1 {
+					if iface, ok := ret[0].Interface().(slog.Handler); ok && iface != nil {
+						h = iface
+					}
+				}
+			}
+		}
+	}
+
+	if h == nil {
+		h = slog.NewJSONHandler(s.opts.Out, handleOpt)
+	}
+
+	s.handler = &wrapper{h: h.WithAttrs(attrs)}
 	s.handler.level.Store(int64(loggerToSlogLevel(s.opts.Level)))
 	s.mu.Unlock()
 
@@ -201,7 +229,12 @@ func (s *slogLogger) Error(ctx context.Context, msg string, attrs ...interface{}
 
 func (s *slogLogger) Fatal(ctx context.Context, msg string, attrs ...interface{}) {
 	s.printLog(ctx, logger.FatalLevel, msg, attrs...)
-	os.Exit(1)
+	for _, fn := range s.opts.FatalFinalizers {
+		fn(ctx)
+	}
+	if closer, ok := s.opts.Out.(io.Closer); ok {
+		closer.Close()
+	}
 }
 
 func (s *slogLogger) Warn(ctx context.Context, msg string, attrs ...interface{}) {
@@ -247,7 +280,7 @@ func (s *slogLogger) printLog(ctx context.Context, lvl logger.Level, msg string,
 		}
 	}
 
-	if s.opts.AddStacktrace && lvl == logger.ErrorLevel {
+	if s.opts.AddStacktrace && (lvl == logger.FatalLevel || lvl == logger.ErrorLevel) {
 		stackInfo := make([]byte, 1024*1024)
 		if stackSize := runtime.Stack(stackInfo, false); stackSize > 0 {
 			traceLines := reTrace.Split(string(stackInfo[:stackSize]), -1)
@@ -285,6 +318,8 @@ func loggerToSlogLevel(level logger.Level) slog.Level {
 		return slog.LevelDebug - 1
 	case logger.FatalLevel:
 		return slog.LevelError + 1
+	case logger.NoneLevel:
+		return slog.LevelError + 2
 	default:
 		return slog.LevelInfo
 	}
@@ -302,6 +337,8 @@ func slogToLoggerLevel(level slog.Level) logger.Level {
 		return logger.TraceLevel
 	case slog.LevelError + 1:
 		return logger.FatalLevel
+	case slog.LevelError + 2:
+		return logger.NoneLevel
 	default:
 		return logger.InfoLevel
 	}
@@ -318,7 +355,7 @@ func (s *slogLogger) argsAttrs(args []interface{}) ([]slog.Attr, error) {
 		case string:
 			if idx+1 < len(args) {
 				attrs = append(attrs, slog.Any(arg, args[idx+1]))
-				idx += 1
+				idx++
 			} else {
 				attrs = append(attrs, slog.String(badKey, arg))
 			}
@@ -330,3 +367,15 @@ func (s *slogLogger) argsAttrs(args []interface{}) ([]slog.Attr, error) {
 
 	return attrs, err
 }
+
+type handlerKey struct{}
+
+func WithHandler(h slog.Handler) logger.Option {
+	return logger.SetOption(handlerKey{}, h)
+}
+
+type handlerFnKey struct{}
+
+func WithHandlerFunc(fn any) logger.Option {
+	return logger.SetOption(handlerFnKey{}, fn)
+}

logger/slog/slog_test.go

@@ -6,15 +6,163 @@ import (
 	"errors"
 	"fmt"
 	"log"
+	"log/slog"
 	"strings"
 	"testing"
+	"time"
 
 	"github.com/google/uuid"
-	"go.unistack.org/micro/v3/metadata"
-
 	"go.unistack.org/micro/v3/logger"
+	"go.unistack.org/micro/v3/metadata"
+	"go.unistack.org/micro/v3/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),
+		WithHandlerFunc(slog.NewTextHandler),
+		logger.WithAddStacktrace(true),
+	)
+	if err := l.Init(logger.WithFields("key1", "val1")); err != nil {
+		t.Fatal(err)
+	}
+
+	l.Error(ctx, "msg1", errors.New("err"))
+
+	if !bytes.Contains(buf.Bytes(), []byte(`slog_test.go:32`)) {
+		t.Fatalf("logger error not works, buf contains: %s", buf.Bytes())
+	}
+}
+
+func TestNoneLevel(t *testing.T) {
+	ctx := context.TODO()
+	buf := bytes.NewBuffer(nil)
+	l := NewLogger(logger.WithLevel(logger.NoneLevel), logger.WithOutput(buf),
+		WithHandlerFunc(slog.NewTextHandler),
+		logger.WithAddStacktrace(true),
+	)
+	if err := l.Init(logger.WithFields("key1", "val1")); err != nil {
+		t.Fatal(err)
+	}
+
+	l.Error(ctx, "msg1", errors.New("err"))
+
+	if buf.Len() != 0 {
+		t.Fatalf("logger none level not works, buf contains: %s", buf.Bytes())
+	}
+}
+
+func TestDelayedBuffer(t *testing.T) {
+	ctx := context.TODO()
+	buf := bytes.NewBuffer(nil)
+	dbuf := buffer.NewDelayedBuffer(100, 100*time.Millisecond, buf)
+	l := NewLogger(logger.WithLevel(logger.ErrorLevel), logger.WithOutput(dbuf),
+		WithHandlerFunc(slog.NewTextHandler),
+		logger.WithAddStacktrace(true),
+	)
+	if err := l.Init(logger.WithFields("key1", "val1")); err != nil {
+		t.Fatal(err)
+	}
+
+	l.Error(ctx, "msg1", errors.New("err"))
+	time.Sleep(120 * time.Millisecond)
+	if !bytes.Contains(buf.Bytes(), []byte(`key1=val1`)) {
+		t.Fatalf("logger delayed buffer not works, buf contains: %s", buf.Bytes())
+	}
+}
+
+func TestTime(t *testing.T) {
+	ctx := context.TODO()
+	buf := bytes.NewBuffer(nil)
+	l := NewLogger(logger.WithLevel(logger.ErrorLevel), logger.WithOutput(buf),
+		WithHandlerFunc(slog.NewTextHandler),
+		logger.WithAddStacktrace(true),
+		logger.WithTimeFunc(func() time.Time {
+			return time.Unix(0, 0).UTC()
+		}),
+	)
+	if err := l.Init(logger.WithFields("key1", "val1")); err != nil {
+		t.Fatal(err)
+	}
+
+	l.Error(ctx, "msg1", errors.New("err"))
+
+	if !bytes.Contains(buf.Bytes(), []byte(`timestamp=1970-01-01T00:00:00.000000000Z`)) {
+		t.Fatalf("logger error not works, buf contains: %s", buf.Bytes())
+	}
+}
+
+func TestWithFields(t *testing.T) {
+	ctx := context.TODO()
+	buf := bytes.NewBuffer(nil)
+	l := NewLogger(logger.WithLevel(logger.InfoLevel), logger.WithOutput(buf),
+		WithHandlerFunc(slog.NewTextHandler),
+		logger.WithDedupKeys(true),
+	)
+	if err := l.Init(logger.WithFields("key1", "val1")); err != nil {
+		t.Fatal(err)
+	}
+
+	l.Info(ctx, "msg1")
+
+	l = l.Fields("key1", "val2")
+
+	l.Info(ctx, "msg2")
+
+	if !bytes.Contains(buf.Bytes(), []byte(`msg=msg2 key1=val1`)) {
+		t.Fatalf("logger error not works, buf contains: %s", buf.Bytes())
+	}
+}
+
+func TestWithDedupKeysWithAddFields(t *testing.T) {
+	ctx := context.TODO()
+	buf := bytes.NewBuffer(nil)
+	l := NewLogger(logger.WithLevel(logger.InfoLevel), logger.WithOutput(buf),
+		WithHandlerFunc(slog.NewTextHandler),
+		logger.WithDedupKeys(true),
+	)
+	if err := l.Init(logger.WithFields("key1", "val1")); err != nil {
+		t.Fatal(err)
+	}
+
+	l.Info(ctx, "msg1")
+
+	if err := l.Init(logger.WithAddFields("key2", "val2")); err != nil {
+		t.Fatal(err)
+	}
+
+	l.Info(ctx, "msg2")
+
+	if err := l.Init(logger.WithAddFields("key2", "val3", "key1", "val4")); err != nil {
+		t.Fatal(err)
+	}
+
+	l.Info(ctx, "msg3")
+
+	if !bytes.Contains(buf.Bytes(), []byte(`msg=msg3 key1=val4 key2=val3`)) {
+		t.Fatalf("logger error not works, buf contains: %s", buf.Bytes())
+	}
+}
+
+func TestWithHandlerFunc(t *testing.T) {
+	ctx := context.TODO()
+	buf := bytes.NewBuffer(nil)
+	l := NewLogger(logger.WithLevel(logger.InfoLevel), logger.WithOutput(buf),
+		WithHandlerFunc(slog.NewTextHandler),
+	)
+	if err := l.Init(); err != nil {
+		t.Fatal(err)
+	}
+
+	l.Info(ctx, "msg1")
+
+	if !bytes.Contains(buf.Bytes(), []byte(`msg=msg1`)) {
+		t.Fatalf("logger error not works, buf contains: %s", buf.Bytes())
+	}
+}
+
 func TestWithAddFields(t *testing.T) {
 	ctx := context.TODO()
 	buf := bytes.NewBuffer(nil)
@@ -115,7 +263,7 @@ func TestErrorf(t *testing.T) {
 
 	buf := bytes.NewBuffer(nil)
 	l := NewLogger(logger.WithLevel(logger.ErrorLevel), logger.WithOutput(buf), logger.WithAddStacktrace(true))
-	if err := l.Init(logger.WithContextAttrFuncs(func(ctx context.Context) []interface{} {
+	if err := l.Init(logger.WithContextAttrFuncs(func(_ context.Context) []interface{} {
 		return nil
 	})); err != nil {
 		t.Fatal(err)
@@ -275,15 +423,16 @@ func TestLogger(t *testing.T) {
 func Test_WithContextAttrFunc(t *testing.T) {
 	loggerContextAttrFuncs := []logger.ContextAttrFunc{
 		func(ctx context.Context) []interface{} {
-			md, ok := metadata.FromIncomingContext(ctx)
+			md, ok := metadata.FromOutgoingContext(ctx)
 			if !ok {
 				return nil
 			}
 			attrs := make([]interface{}, 0, 10)
 			for k, v := range md {
-				switch k {
+				key := strings.ToLower(k)
-				case "X-Request-Id", "Phone", "External-Id", "Source-Service", "X-App-Install-Id", "Client-Id", "Client-Ip":
+				switch key {
-					attrs = append(attrs, strings.ToLower(k), v)
+				case "x-request-id", "phone", "external-Id", "source-service", "x-app-install-id", "client-id", "client-ip":
+					attrs = append(attrs, key, v)
 				}
 			}
 			return attrs
@@ -293,7 +442,7 @@ func Test_WithContextAttrFunc(t *testing.T) {
 	logger.DefaultContextAttrFuncs = append(logger.DefaultContextAttrFuncs, loggerContextAttrFuncs...)
 
 	ctx := context.TODO()
-	ctx = metadata.AppendIncomingContext(ctx, "X-Request-Id", uuid.New().String(),
+	ctx = metadata.AppendOutgoingContext(ctx, "X-Request-Id", uuid.New().String(),
 		"Source-Service", "Test-System")
 
 	buf := bytes.NewBuffer(nil)
@@ -306,17 +455,39 @@ func Test_WithContextAttrFunc(t *testing.T) {
 	if !(bytes.Contains(buf.Bytes(), []byte(`"level":"info"`)) && bytes.Contains(buf.Bytes(), []byte(`"msg":"test message"`))) {
 		t.Fatalf("logger info, buf %s", buf.Bytes())
 	}
-	if !(bytes.Contains(buf.Bytes(), []byte(`"x-request-id":"`))) {
+	if !(bytes.Contains(buf.Bytes(), []byte(`"x-request-id":`))) {
 		t.Fatalf("logger info, buf %s", buf.Bytes())
 	}
 	if !(bytes.Contains(buf.Bytes(), []byte(`"source-service":"Test-System"`))) {
 		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())
 }
+
+func TestFatalFinalizers(t *testing.T) {
+	ctx := context.TODO()
+	buf := bytes.NewBuffer(nil)
+	l := NewLogger(
+		logger.WithLevel(logger.TraceLevel),
+		logger.WithOutput(buf),
+	)
+	if err := l.Init(
+		logger.WithFatalFinalizers(func(ctx context.Context) {
+			l.Info(ctx, "fatal finalizer")
+		})); err != nil {
+		t.Fatal(err)
+	}
+	l.Fatal(ctx, "info_msg1")
+	if !bytes.Contains(buf.Bytes(), []byte("fatal finalizer")) {
+		t.Fatalf("logger dont have fatal message, buf %s", buf.Bytes())
+	}
+	if !bytes.Contains(buf.Bytes(), []byte("info_msg1")) {
+		t.Fatalf("logger dont have info_msg1 message, buf %s", buf.Bytes())
+	}
+}

logger/unwrap/unwrap.go

@@ -36,14 +36,14 @@ var (
 	circularShortBytes = []byte("<shown>")
 	invalidAngleBytes  = []byte("<invalid>")
 	filteredBytes      = []byte("<filtered>")
-	openBracketBytes   = []byte("[")
+	// openBracketBytes   = []byte("[")
-	closeBracketBytes  = []byte("]")
+	// closeBracketBytes  = []byte("]")
-	percentBytes       = []byte("%")
+	percentBytes    = []byte("%")
-	precisionBytes     = []byte(".")
+	precisionBytes  = []byte(".")
-	openAngleBytes     = []byte("<")
+	openAngleBytes  = []byte("<")
-	closeAngleBytes    = []byte(">")
+	closeAngleBytes = []byte(">")
-	openMapBytes       = []byte("{")
+	openMapBytes    = []byte("{")
-	closeMapBytes      = []byte("}")
+	closeMapBytes   = []byte("}")
 )
 
 type protoMessage interface {
@@ -52,13 +52,15 @@ type protoMessage interface {
 }
 
 type Wrapper struct {
-	val              interface{}
+	pointers map[uintptr]int
-	s                fmt.State
+	takeMap  map[int]bool
-	pointers         map[uintptr]int
+
-	opts             *Options
+	val  interface{}
+	s    fmt.State
+	opts *Options
+
 	depth            int
 	ignoreNextType   bool
-	takeMap          map[int]bool
 	protoWrapperType bool
 	sqlWrapperType   bool
 }

logger/unwrap/unwrap_test.go

@@ -82,12 +82,12 @@ func TestTagged(t *testing.T) {
 func TestTaggedNested(t *testing.T) {
 	type val struct {
 		key string `logger:"take"`
-		val string `logger:"omit"`
+		// val string `logger:"omit"`
 		unk string
 	}
 	type str struct {
-		key string `logger:"omit"`
+		// key string `logger:"omit"`
-		val *val   `logger:"take"`
+		val *val `logger:"take"`
 	}
 
 	var iface interface{}

metadata/context.go

@@ -24,6 +24,17 @@ func FromIncomingContext(ctx context.Context) (Metadata, bool) {
 	return md.md, ok
 }
 
+// MustIncomingContext returns metadata from incoming ctx
+// returned metadata shoud not be modified or race condition happens.
+// If metadata not exists panics.
+func MustIncomingContext(ctx context.Context) Metadata {
+	md, ok := FromIncomingContext(ctx)
+	if !ok {
+		panic("missing metadata")
+	}
+	return md
+}
+
 // FromOutgoingContext returns metadata from outgoing ctx
 // returned metadata shoud not be modified or race condition happens
 func FromOutgoingContext(ctx context.Context) (Metadata, bool) {
@@ -37,6 +48,17 @@ func FromOutgoingContext(ctx context.Context) (Metadata, bool) {
 	return md.md, ok
 }
 
+// MustOutgoingContext returns metadata from outgoing ctx
+// returned metadata shoud not be modified or race condition happens.
+// If metadata not exists panics.
+func MustOutgoingContext(ctx context.Context) Metadata {
+	md, ok := FromOutgoingContext(ctx)
+	if !ok {
+		panic("missing metadata")
+	}
+	return md
+}
+
 // FromContext returns metadata from the given context
 // returned metadata shoud not be modified or race condition happens
 func FromContext(ctx context.Context) (Metadata, bool) {
@@ -50,15 +72,22 @@ func FromContext(ctx context.Context) (Metadata, bool) {
 	return md.md, ok
 }
 
+// MustContext returns metadata from the given context
+// returned metadata shoud not be modified or race condition happens
+func MustContext(ctx context.Context) Metadata {
+	md, ok := FromContext(ctx)
+	if !ok {
+		panic("missing metadata")
+	}
+	return md
+}
+
 // NewContext creates a new context with the given metadata
 func NewContext(ctx context.Context, md Metadata) context.Context {
 	if ctx == nil {
 		ctx = context.Background()
 	}
-	ctx = context.WithValue(ctx, mdKey{}, &rawMetadata{md})
+	return context.WithValue(ctx, mdKey{}, &rawMetadata{md})
-	ctx = context.WithValue(ctx, mdIncomingKey{}, &rawMetadata{})
-	ctx = context.WithValue(ctx, mdOutgoingKey{}, &rawMetadata{})
-	return ctx
 }
 
 // SetOutgoingContext modify outgoing context with given metadata
@@ -90,11 +119,7 @@ func NewIncomingContext(ctx context.Context, md Metadata) context.Context {
 	if ctx == nil {
 		ctx = context.Background()
 	}
-	ctx = context.WithValue(ctx, mdIncomingKey{}, &rawMetadata{md})
+	return context.WithValue(ctx, mdIncomingKey{}, &rawMetadata{md})
-	if v, ok := ctx.Value(mdOutgoingKey{}).(*rawMetadata); !ok || v == nil {
-		ctx = context.WithValue(ctx, mdOutgoingKey{}, &rawMetadata{})
-	}
-	return ctx
 }
 
 // NewOutgoingContext creates a new context with outcoming metadata attached
@@ -102,11 +127,7 @@ func NewOutgoingContext(ctx context.Context, md Metadata) context.Context {
 	if ctx == nil {
 		ctx = context.Background()
 	}
-	ctx = context.WithValue(ctx, mdOutgoingKey{}, &rawMetadata{md})
+	return context.WithValue(ctx, mdOutgoingKey{}, &rawMetadata{md})
-	if v, ok := ctx.Value(mdIncomingKey{}).(*rawMetadata); !ok || v == nil {
-		ctx = context.WithValue(ctx, mdIncomingKey{}, &rawMetadata{})
-	}
-	return ctx
 }
 
 // AppendOutgoingContext apends new md to context
@@ -122,7 +143,7 @@ func AppendOutgoingContext(ctx context.Context, kv ...string) context.Context {
 	for k, v := range md {
 		omd.Set(k, v)
 	}
-	return NewOutgoingContext(ctx, omd)
+	return ctx
 }
 
 // AppendIncomingContext apends new md to context
@@ -138,5 +159,21 @@ func AppendIncomingContext(ctx context.Context, kv ...string) context.Context {
 	for k, v := range md {
 		omd.Set(k, v)
 	}
-	return NewIncomingContext(ctx, omd)
+	return ctx
+}
+
+// AppendContext apends new md to context
+func AppendContext(ctx context.Context, kv ...string) context.Context {
+	md, ok := Pairs(kv...)
+	if !ok {
+		return ctx
+	}
+	omd, ok := FromContext(ctx)
+	if !ok {
+		return NewContext(ctx, md)
+	}
+	for k, v := range md {
+		omd.Set(k, v)
+	}
+	return ctx
 }

metadata/metadata.go

@@ -4,6 +4,7 @@ package metadata
 import (
 	"net/textproto"
 	"sort"
+	"strings"
 )
 
 var (
@@ -66,6 +67,14 @@ func (md Metadata) Iterator() *Iterator {
 	return iter
 }
 
+func (md Metadata) MustGet(key string) string {
+	val, ok := md.Get(key)
+	if !ok {
+		panic("missing metadata key")
+	}
+	return val
+}
+
 // Get returns value from metadata by key
 func (md Metadata) Get(key string) (string, bool) {
 	// fast path
@@ -73,6 +82,9 @@ func (md Metadata) Get(key string) (string, bool) {
 	if !ok {
 		// slow path
 		val, ok = md[textproto.CanonicalMIMEHeaderKey(key)]
+		if !ok {
+			val, ok = md[strings.ToLower(key)]
+		}
 	}
 	return val, ok
 }
@@ -94,14 +106,23 @@ func (md Metadata) Del(keys ...string) {
 		delete(md, key)
 		// slow path
 		delete(md, textproto.CanonicalMIMEHeaderKey(key))
+		// very slow path
+		delete(md, strings.ToLower(key))
+	}
+}
+
+// Copy makes a copy of the metadata
+func (md Metadata) CopyTo(dst Metadata) {
+	for k, v := range md {
+		dst[k] = v
 	}
 }
 
 // Copy makes a copy of the metadata
 func Copy(md Metadata, exclude ...string) Metadata {
 	nmd := New(len(md))
-	for key, val := range md {
+	for k, v := range md {
-		nmd.Set(key, val)
+		nmd[k] = v
 	}
 	nmd.Del(exclude...)
 	return nmd
@@ -125,7 +146,7 @@ func Merge(omd Metadata, mmd Metadata, overwrite bool) Metadata {
 		case ok && !overwrite:
 			continue
 		case val != "":
-			nmd.Set(key, val)
+			nmd[key] = val
 		case ok && val == "":
 			nmd.Del(key)
 		}
@@ -139,6 +160,8 @@ func Pairs(kv ...string) (Metadata, bool) {
 		return nil, false
 	}
 	md := New(len(kv) / 2)
-	md.Set(kv...)
+	for idx := 0; idx < len(kv); idx += 2 {
+		md[kv[idx]] = kv[idx+1]
+	}
 	return md, true
 }

metadata/metadata_test.go

@@ -5,6 +5,37 @@ import (
 	"testing"
 )
 
+func TestLowercase(t *testing.T) {
+	md := New(1)
+	md["x-request-id"] = "12345"
+	v, ok := md.Get("X-Request-Id")
+	if !ok || v == "" {
+		t.Fatalf("metadata invalid %#+v", md)
+	}
+}
+
+func TestMultipleUsage(t *testing.T) {
+	ctx := context.TODO()
+	md := New(0)
+	md.Set("key1_1", "val1_1", "key1_2", "val1_2", "key1_3", "val1_3")
+	ctx = NewIncomingContext(ctx, Copy(md))
+	ctx = NewOutgoingContext(ctx, Copy(md))
+	imd, _ := FromIncomingContext(ctx)
+	omd, _ := FromOutgoingContext(ctx)
+	_ = func(x context.Context) context.Context {
+		m, _ := FromIncomingContext(x)
+		m.Del("key1_2")
+		return ctx
+	}(ctx)
+	_ = func(x context.Context) context.Context {
+		m, _ := FromIncomingContext(x)
+		m.Del("key1_3")
+		return ctx
+	}(ctx)
+	_ = imd
+	_ = omd
+}
+
 func TestMetadataSetMultiple(t *testing.T) {
 	md := New(4)
 	md.Set("key1", "val1", "key2", "val2", "key3")
@@ -57,6 +88,13 @@ func TestPassing(t *testing.T) {
 
 	ctx = NewIncomingContext(ctx, md1)
 	testCtx(ctx)
+	_, ok := FromOutgoingContext(ctx)
+	if ok {
+		t.Fatalf("create outgoing context")
+	}
+
+	ctx = NewOutgoingContext(ctx, New(1))
+	testCtx(ctx)
 	md, ok := FromOutgoingContext(ctx)
 	if !ok {
 		t.Fatalf("missing metadata from outgoing context")
@@ -80,7 +118,7 @@ func TestMerge(t *testing.T) {
 	}
 }
 
-func TestIterator(t *testing.T) {
+func TestIterator(_ *testing.T) {
 	md := Metadata{
 		"1Last":   "last",
 		"2First":  "first",

meter/context.go

@@ -15,6 +15,15 @@ func FromContext(ctx context.Context) (Meter, bool) {
 	return c, ok
 }
 
+// MustContext get meter from context
+func MustContext(ctx context.Context) Meter {
+	m, ok := FromContext(ctx)
+	if !ok {
+		panic("missing meter")
+	}
+	return m
+}
+
 // NewContext put meter in context
 func NewContext(ctx context.Context, c Meter) context.Context {
 	if ctx == nil {

meter/meter.go

@@ -4,14 +4,14 @@ package meter
 import (
 	"io"
 	"sort"
-	"strconv"
 	"strings"
+	"sync"
 	"time"
 )
 
 var (
 	// DefaultMeter is the default meter
-	DefaultMeter Meter = NewMeter()
+	DefaultMeter = NewMeter()
 	// DefaultAddress data will be made available on this host:port
 	DefaultAddress = ":9090"
 	// DefaultPath the meter endpoint where the Meter data will be made available
@@ -49,9 +49,11 @@ type Meter interface {
 	Set(opts ...Option) Meter
 	// Histogram get or create histogram
 	Histogram(name string, labels ...string) Histogram
+	// HistogramExt get or create histogram with specified quantiles
+	HistogramExt(name string, quantiles []float64, labels ...string) Histogram
 	// Summary get or create summary
 	Summary(name string, labels ...string) Summary
-	// SummaryExt get or create summary with spcified quantiles and window time
+	// SummaryExt get or create summary with specified quantiles and window time
 	SummaryExt(name string, window time.Duration, quantiles []float64, labels ...string) Summary
 	// Write writes metrics to io.Writer
 	Write(w io.Writer, opts ...Option) error
@@ -59,6 +61,8 @@ type Meter interface {
 	Options() Options
 	// String return meter type
 	String() string
+	// Unregister metric name and drop all data
+	Unregister(name string, labels ...string) bool
 }
 
 // Counter is a counter
@@ -80,7 +84,11 @@ type FloatCounter interface {
 
 // Gauge is a float64 gauge
 type Gauge interface {
+	Add(float64)
 	Get() float64
+	Set(float64)
+	Dec()
+	Inc()
 }
 
 // Histogram is a histogram for non-negative values with automatically created buckets
@@ -117,6 +125,39 @@ func BuildLabels(labels ...string) []string {
 	return labels
 }
 
+var spool = newStringsPool(500)
+
+type stringsPool struct {
+	p *sync.Pool
+	c int
+}
+
+func newStringsPool(size int) *stringsPool {
+	p := &stringsPool{c: size}
+	p.p = &sync.Pool{
+		New: func() interface{} {
+			return &strings.Builder{}
+		},
+	}
+	return p
+}
+
+func (p *stringsPool) Cap() int {
+	return p.c
+}
+
+func (p *stringsPool) Get() *strings.Builder {
+	return p.p.Get().(*strings.Builder)
+}
+
+func (p *stringsPool) Put(b *strings.Builder) {
+	if b.Cap() > p.c {
+		return
+	}
+	b.Reset()
+	p.p.Put(b)
+}
+
 // BuildName used to combine metric with labels.
 // If labels count is odd, drop last element
 func BuildName(name string, labels ...string) string {
@@ -125,8 +166,6 @@ func BuildName(name string, labels ...string) string {
 	}
 
 	if len(labels) > 2 {
-		sort.Sort(byKey(labels))
-
 		idx := 0
 		for {
 			if labels[idx] == labels[idx+2] {
@@ -141,7 +180,9 @@ func BuildName(name string, labels ...string) string {
 		}
 	}
 
-	var b strings.Builder
+	b := spool.Get()
+	defer spool.Put(b)
+
 	_, _ = b.WriteString(name)
 	_, _ = b.WriteRune('{')
 	for idx := 0; idx < len(labels); idx += 2 {
@@ -149,8 +190,9 @@ func BuildName(name string, labels ...string) string {
 			_, _ = b.WriteRune(',')
 		}
 		_, _ = b.WriteString(labels[idx])
-		_, _ = b.WriteString(`=`)
+		_, _ = b.WriteString(`="`)
-		_, _ = b.WriteString(strconv.Quote(labels[idx+1]))
+		_, _ = b.WriteString(labels[idx+1])
+		_, _ = b.WriteRune('"')
 	}
 	_, _ = b.WriteRune('}')
 

meter/meter_test.go

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

meter/noop.go

@@ -28,6 +28,10 @@ func (r *noopMeter) Name() string {
 	return r.opts.Name
 }
 
+func (r *noopMeter) Unregister(name string, labels ...string) bool {
+	return true
+}
+
 // Init initialize options
 func (r *noopMeter) Init(opts ...Option) error {
 	for _, o := range opts {
@@ -37,32 +41,37 @@ func (r *noopMeter) Init(opts ...Option) error {
 }
 
 // Counter implements the Meter interface
-func (r *noopMeter) Counter(name string, labels ...string) Counter {
+func (r *noopMeter) Counter(_ string, labels ...string) Counter {
 	return &noopCounter{labels: labels}
 }
 
 // FloatCounter implements the Meter interface
-func (r *noopMeter) FloatCounter(name string, labels ...string) FloatCounter {
+func (r *noopMeter) FloatCounter(_ string, labels ...string) FloatCounter {
 	return &noopFloatCounter{labels: labels}
 }
 
 // Gauge implements the Meter interface
-func (r *noopMeter) Gauge(name string, f func() float64, labels ...string) Gauge {
+func (r *noopMeter) Gauge(_ string, _ func() float64, labels ...string) Gauge {
 	return &noopGauge{labels: labels}
 }
 
 // Summary implements the Meter interface
-func (r *noopMeter) Summary(name string, labels ...string) Summary {
+func (r *noopMeter) Summary(_ string, labels ...string) Summary {
 	return &noopSummary{labels: labels}
 }
 
 // SummaryExt implements the Meter interface
-func (r *noopMeter) SummaryExt(name string, window time.Duration, quantiles []float64, labels ...string) Summary {
+func (r *noopMeter) SummaryExt(_ string, _ time.Duration, _ []float64, labels ...string) Summary {
 	return &noopSummary{labels: labels}
 }
 
 // Histogram implements the Meter interface
-func (r *noopMeter) Histogram(name string, labels ...string) Histogram {
+func (r *noopMeter) Histogram(_ string, labels ...string) Histogram {
+	return &noopHistogram{labels: labels}
+}
+
+// HistogramExt implements the Meter interface
+func (r *noopMeter) HistogramExt(_ string, quantiles []float64, labels ...string) Histogram {
 	return &noopHistogram{labels: labels}
 }
 
@@ -77,7 +86,7 @@ func (r *noopMeter) Set(opts ...Option) Meter {
 	return m
 }
 
-func (r *noopMeter) Write(w io.Writer, opts ...Option) error {
+func (r *noopMeter) Write(_ io.Writer, _ ...Option) error {
 	return nil
 }
 
@@ -132,6 +141,18 @@ type noopGauge struct {
 	labels []string
 }
 
+func (r *noopGauge) Add(float64) {
+}
+
+func (r *noopGauge) Set(float64) {
+}
+
+func (r *noopGauge) Inc() {
+}
+
+func (r *noopGauge) Dec() {
+}
+
 func (r *noopGauge) Get() float64 {
 	return 0
 }

meter/options.go

@@ -4,6 +4,8 @@ import (
 	"context"
 )
 
+var DefaultQuantiles = []float64{.005, .01, .025, .05, .1, .25, .5, 1, 2.5, 5, 10}
+
 // Option powers the configuration for metrics implementations:
 type Option func(*Options)
 
@@ -23,6 +25,8 @@ type Options struct {
 	WriteProcessMetrics bool
 	// WriteFDMetrics flag to write fd metrics
 	WriteFDMetrics bool
+	// Quantiles specifies buckets for histogram
+	Quantiles []float64
 }
 
 // NewOptions prepares a set of options:
@@ -61,14 +65,12 @@ func Address(value string) Option {
 	}
 }
 
-/*
+// Quantiles defines the desired spread of statistics for histogram metrics:
-// TimingObjectives defines the desired spread of statistics for histogram / timing metrics:
+func Quantiles(quantiles []float64) Option {
-func TimingObjectives(value map[float64]float64) Option {
 	return func(o *Options) {
-		o.TimingObjectives = value
+		o.Quantiles = quantiles
 	}
 }
-*/
 
 // Labels add the meter labels
 func Labels(ls ...string) Option {

micro.go

@@ -65,6 +65,8 @@ func As(b any, target any) bool {
 			break
 		case targetType.Implements(routerType):
 			break
+		case targetType.Implements(tracerType):
+			break
 		default:
 			return false
 		}
@@ -76,19 +78,21 @@ func As(b any, target any) bool {
 	return false
 }
 
-var brokerType = reflect.TypeOf((*broker.Broker)(nil)).Elem()
+var (
-var loggerType = reflect.TypeOf((*logger.Logger)(nil)).Elem()
+	brokerType   = reflect.TypeOf((*broker.Broker)(nil)).Elem()
-var clientType = reflect.TypeOf((*client.Client)(nil)).Elem()
+	loggerType   = reflect.TypeOf((*logger.Logger)(nil)).Elem()
-var serverType = reflect.TypeOf((*server.Server)(nil)).Elem()
+	clientType   = reflect.TypeOf((*client.Client)(nil)).Elem()
-var codecType = reflect.TypeOf((*codec.Codec)(nil)).Elem()
+	serverType   = reflect.TypeOf((*server.Server)(nil)).Elem()
-var flowType = reflect.TypeOf((*flow.Flow)(nil)).Elem()
+	codecType    = reflect.TypeOf((*codec.Codec)(nil)).Elem()
-var fsmType = reflect.TypeOf((*fsm.FSM)(nil)).Elem()
+	flowType     = reflect.TypeOf((*flow.Flow)(nil)).Elem()
-var meterType = reflect.TypeOf((*meter.Meter)(nil)).Elem()
+	fsmType      = reflect.TypeOf((*fsm.FSM)(nil)).Elem()
-var registerType = reflect.TypeOf((*register.Register)(nil)).Elem()
+	meterType    = reflect.TypeOf((*meter.Meter)(nil)).Elem()
-var resolverType = reflect.TypeOf((*resolver.Resolver)(nil)).Elem()
+	registerType = reflect.TypeOf((*register.Register)(nil)).Elem()
-var routerType = reflect.TypeOf((*router.Router)(nil)).Elem()
+	resolverType = reflect.TypeOf((*resolver.Resolver)(nil)).Elem()
-var selectorType = reflect.TypeOf((*selector.Selector)(nil)).Elem()
+	routerType   = reflect.TypeOf((*router.Router)(nil)).Elem()
-var storeType = reflect.TypeOf((*store.Store)(nil)).Elem()
+	selectorType = reflect.TypeOf((*selector.Selector)(nil)).Elem()
-var syncType = reflect.TypeOf((*sync.Sync)(nil)).Elem()
+	storeType    = reflect.TypeOf((*store.Store)(nil)).Elem()
-var tracerType = reflect.TypeOf((*tracer.Tracer)(nil)).Elem()
+	syncType     = reflect.TypeOf((*sync.Sync)(nil)).Elem()
-var serviceType = reflect.TypeOf((*Service)(nil)).Elem()
+	tracerType   = reflect.TypeOf((*tracer.Tracer)(nil)).Elem()
+	serviceType  = reflect.TypeOf((*Service)(nil)).Elem()
+)

micro_test.go

@@ -18,26 +18,27 @@ func TestAs(t *testing.T) {
 	testCases := []struct {
 		b      any
 		target any
-		match  bool
 		want   any
+
+		match bool
 	}{
 		{
-			broTarget,
+			b:      broTarget,
-			&b,
+			target: &b,
-			true,
+			match:  true,
-			broTarget,
+			want:   broTarget,
 		},
 		{
-			nil,
+			b:      nil,
-			&b,
+			target: &b,
-			false,
+			match:  false,
-			nil,
+			want:   nil,
 		},
 		{
-			fsmTarget,
+			b:      fsmTarget,
-			&b,
+			target: &b,
-			false,
+			match:  false,
-			nil,
+			want:   nil,
 		},
 	}
 	for i, tc := range testCases {
@@ -66,7 +67,13 @@ type bro struct {
 
 func (p *bro) Name() string { return p.name }
 
-func (p *bro) Init(opts ...broker.Option) error { return nil }
+func (p *bro) Live() bool { return true }
+
+func (p *bro) Ready() bool { return true }
+
+func (p *bro) Health() bool { return true }
+
+func (p *bro) Init(_ ...broker.Option) error { return nil }
 
 // Options returns broker options
 func (p *bro) Options() broker.Options { return broker.Options{} }
@@ -75,28 +82,28 @@ func (p *bro) Options() broker.Options { return broker.Options{} }
 func (p *bro) Address() string { return "" }
 
 // Connect connects to broker
-func (p *bro) Connect(ctx context.Context) error { return nil }
+func (p *bro) Connect(_ context.Context) error { return nil }
 
 // Disconnect disconnect from broker
-func (p *bro) Disconnect(ctx context.Context) error { return nil }
+func (p *bro) Disconnect(_ context.Context) error { return nil }
 
 // Publish message, msg can be single broker.Message or []broker.Message
-func (p *bro) Publish(ctx context.Context, topic string, msg *broker.Message, opts ...broker.PublishOption) error {
+func (p *bro) Publish(_ context.Context, _ string, _ *broker.Message, _ ...broker.PublishOption) error {
 	return nil
 }
 
 // BatchPublish messages to broker with multiple topics
-func (p *bro) BatchPublish(ctx context.Context, msgs []*broker.Message, opts ...broker.PublishOption) error {
+func (p *bro) BatchPublish(_ context.Context, _ []*broker.Message, _ ...broker.PublishOption) error {
 	return nil
 }
 
 // BatchSubscribe subscribes to topic messages via handler
-func (p *bro) BatchSubscribe(ctx context.Context, topic string, h broker.BatchHandler, opts ...broker.SubscribeOption) (broker.Subscriber, error) {
+func (p *bro) BatchSubscribe(_ context.Context, _ string, _ broker.BatchHandler, _ ...broker.SubscribeOption) (broker.Subscriber, error) {
 	return nil, nil
 }
 
 // Subscribe subscribes to topic message via handler
-func (p *bro) Subscribe(ctx context.Context, topic string, handler broker.Handler, opts ...broker.SubscribeOption) (broker.Subscriber, error) {
+func (p *bro) Subscribe(_ context.Context, _ string, _ broker.Handler, _ ...broker.SubscribeOption) (broker.Subscriber, error) {
 	return nil, nil
 }
 
@@ -107,9 +114,9 @@ type fsmT struct {
 	name string
 }
 
-func (f *fsmT) Start(ctx context.Context, a interface{}, o ...Option) (interface{}, error) {
+func (f *fsmT) Start(_ context.Context, _ interface{}, _ ...Option) (interface{}, error) {
 	return nil, nil
 }
-func (f *fsmT) Current() string                  { return f.name }
+func (f *fsmT) Current() string                 { return f.name }
-func (f *fsmT) Reset()                           {}
+func (f *fsmT) Reset()                          {}
-func (f *fsmT) State(s string, sf fsm.StateFunc) {}
+func (f *fsmT) State(_ string, _ fsm.StateFunc) {}

mtls/options.go

@@ -8,19 +8,20 @@ import (
 
 // CertificateOptions holds options for x509.CreateCertificate
 type CertificateOptions struct {
-	Organization          []string
-	OrganizationalUnit    []string
-	CommonName            string
-	OCSPServer            []string
-	IssuingCertificateURL []string
 	SerialNumber          *big.Int
 	NotAfter              time.Time
 	NotBefore             time.Time
-	SignatureAlgorithm    x509.SignatureAlgorithm
+	CommonName            string
-	PublicKeyAlgorithm    x509.PublicKeyAlgorithm
+	Organization          []string
+	OrganizationalUnit    []string
+	OCSPServer            []string
+	IssuingCertificateURL []string
 	ExtKeyUsage           []x509.ExtKeyUsage
-	KeyUsage              x509.KeyUsage
+
-	IsCA                  bool
+	SignatureAlgorithm x509.SignatureAlgorithm
+	PublicKeyAlgorithm x509.PublicKeyAlgorithm
+	KeyUsage           x509.KeyUsage
+	IsCA               bool
 }
 
 // CertificateOrganizationalUnit set OrganizationalUnit in certificate subject

network/options.go

@@ -119,7 +119,7 @@ func Tracer(t tracer.Tracer) Option {
 // NewOptions returns network default options
 func NewOptions(opts ...Option) Options {
 	options := Options{
-		ID:      id.Must(),
+		ID:      id.MustNew(),
 		Name:    "go.micro",
 		Address: ":0",
 		Logger:  logger.DefaultLogger,

network/transport/transport.go

@@ -10,7 +10,7 @@ import (
 
 var (
 	// DefaultTransport is the global default transport
-	DefaultTransport Transport = NewTransport()
+	DefaultTransport = NewTransport()
 	// DefaultDialTimeout the default dial timeout
 	DefaultDialTimeout = time.Second * 5
 )

network/tunnel/broker/broker.go

@@ -45,6 +45,18 @@ type (
 	tunnelAddr struct{}
 )
 
+func (t *tunBroker) Live() bool {
+	return true
+}
+
+func (t *tunBroker) Ready() bool {
+	return true
+}
+
+func (t *tunBroker) Health() bool {
+	return true
+}
+
 func (t *tunBroker) Init(opts ...broker.Option) error {
 	for _, o := range opts {
 		o(&t.opts)
@@ -72,7 +84,7 @@ func (t *tunBroker) Disconnect(ctx context.Context) error {
 	return t.tunnel.Close(ctx)
 }
 
-func (t *tunBroker) BatchPublish(ctx context.Context, msgs []*broker.Message, opts ...broker.PublishOption) error {
+func (t *tunBroker) BatchPublish(ctx context.Context, msgs []*broker.Message, _ ...broker.PublishOption) error {
 	// TODO: this is probably inefficient, we might want to just maintain an open connection
 	// it may be easier to add broadcast to the tunnel
 	topicMap := make(map[string]tunnel.Session)
@@ -102,7 +114,7 @@ func (t *tunBroker) BatchPublish(ctx context.Context, msgs []*broker.Message, op
 	return nil
 }
 
-func (t *tunBroker) Publish(ctx context.Context, topic string, m *broker.Message, opts ...broker.PublishOption) error {
+func (t *tunBroker) Publish(ctx context.Context, topic string, m *broker.Message, _ ...broker.PublishOption) error {
 	// TODO: this is probably inefficient, we might want to just maintain an open connection
 	// it may be easier to add broadcast to the tunnel
 	c, err := t.tunnel.Dial(ctx, topic, tunnel.DialMode(tunnel.Multicast))

network/tunnel/options.go

@@ -164,7 +164,7 @@ func DialWait(b bool) DialOption {
 // NewOptions returns router default options with filled values
 func NewOptions(opts ...Option) Options {
 	options := Options{
-		ID:      id.Must(),
+		ID:      id.MustNew(),
 		Address: DefaultAddress,
 		Token:   DefaultToken,
 		Logger:  logger.DefaultLogger,

options.go

@@ -269,7 +269,7 @@ func Logger(l logger.Logger, opts ...LoggerOption) Option {
 				}
 			}
 		}
-		
+
 		for _, trc := range o.Tracers {
 			for _, ot := range lopts.tracers {
 				if trc.Name() == ot || all {
@@ -294,8 +294,8 @@ type loggerOptions struct {
 	brokers   []string
 	registers []string
 	stores    []string
-	meters    []string
+	// meters    []string
-	tracers   []string
+	tracers []string
 }
 
 /*

profiler/noop.go

@@ -15,6 +15,6 @@ func (p *noopProfiler) String() string {
 }
 
 // NewProfiler returns new noop profiler
-func NewProfiler(opts ...Option) Profiler {
+func NewProfiler(_ ...Option) Profiler {
 	return &noopProfiler{}
 }

profiler/profile.go

@@ -12,7 +12,7 @@ type Profiler interface {
 }
 
 // DefaultProfiler holds the default profiler
-var DefaultProfiler Profiler = NewProfiler()
+var DefaultProfiler = NewProfiler()
 
 // Options holds the options for profiler
 type Options struct {

register/context.go

@@ -15,6 +15,15 @@ func FromContext(ctx context.Context) (Register, bool) {
 	return c, ok
 }
 
+// MustContext get register from context
+func MustContext(ctx context.Context) Register {
+	r, ok := FromContext(ctx)
+	if !ok {
+		panic("missing register")
+	}
+	return r
+}
+
 // NewContext put register in context
 func NewContext(ctx context.Context, c Register) context.Context {
 	if ctx == nil {

register/extractor.go

@@ -1,12 +1,9 @@
 package register
 
 import (
-	"fmt"
 	"reflect"
 	"unicode"
 	"unicode/utf8"
-
-	"go.unistack.org/micro/v3/metadata"
 )
 
 // ExtractValue from reflect.Type from specified depth
@@ -38,53 +35,6 @@ func ExtractValue(v reflect.Type, d int) string {
 	return v.Name()
 }
 
-// ExtractEndpoint extract *Endpoint from reflect.Method
-func ExtractEndpoint(method reflect.Method) *Endpoint {
-	if method.PkgPath != "" {
-		return nil
-	}
-
-	var rspType, reqType reflect.Type
-	var stream bool
-	mt := method.Type
-
-	switch mt.NumIn() {
-	case 3:
-		reqType = mt.In(1)
-		rspType = mt.In(2)
-	case 4:
-		reqType = mt.In(2)
-		rspType = mt.In(3)
-	default:
-		return nil
-	}
-
-	// are we dealing with a stream?
-	switch rspType.Kind() {
-	case reflect.Func, reflect.Interface:
-		stream = true
-	}
-
-	request := ExtractValue(reqType, 0)
-	response := ExtractValue(rspType, 0)
-	if request == "" || response == "" {
-		return nil
-	}
-
-	ep := &Endpoint{
-		Name:     method.Name,
-		Request:  request,
-		Response: response,
-		Metadata: metadata.New(0),
-	}
-
-	if stream {
-		ep.Metadata.Set("stream", fmt.Sprintf("%v", stream))
-	}
-
-	return ep
-}
-
 // ExtractSubValue exctact *Value from reflect.Type
 func ExtractSubValue(typ reflect.Type) string {
 	var reqType reflect.Type

register/extractor_test.go

@@ -2,8 +2,6 @@ package register
 
 import (
 	"context"
-	"reflect"
-	"testing"
 )
 
 type TestHandler struct{}
@@ -15,40 +13,3 @@ type TestResponse struct{}
 func (t *TestHandler) Test(ctx context.Context, req *TestRequest, rsp *TestResponse) error {
 	return nil
 }
-
-func TestExtractEndpoint(t *testing.T) {
-	handler := &TestHandler{}
-	typ := reflect.TypeOf(handler)
-
-	var endpoints []*Endpoint
-
-	for m := 0; m < typ.NumMethod(); m++ {
-		if e := ExtractEndpoint(typ.Method(m)); e != nil {
-			endpoints = append(endpoints, e)
-		}
-	}
-
-	if i := len(endpoints); i != 1 {
-		t.Fatalf("Expected 1 endpoint, have %d", i)
-	}
-
-	if endpoints[0].Name != "Test" {
-		t.Fatalf("Expected handler Test, got %s", endpoints[0].Name)
-	}
-
-	if endpoints[0].Request == "" {
-		t.Fatal("Expected non nil Request")
-	}
-
-	if endpoints[0].Response == "" {
-		t.Fatal("Expected non nil Request")
-	}
-
-	if endpoints[0].Request != "TestRequest" {
-		t.Fatalf("Expected TestRequest got %s", endpoints[0].Request)
-	}
-
-	if endpoints[0].Response != "TestResponse" {
-		t.Fatalf("Expected TestResponse got %s", endpoints[0].Response)
-	}
-}

register/memory/memory.go

@@ -23,18 +23,17 @@ type node struct {
 }
 
 type record struct {
-	Name      string
+	Name     string
-	Version   string
+	Version  string
-	Metadata  map[string]string
+	Metadata map[string]string
-	Nodes     map[string]*node
+	Nodes    map[string]*node
-	Endpoints []*register.Endpoint
 }
 
 type memory struct {
-	sync.RWMutex
 	records  map[string]services
 	watchers map[string]*watcher
 	opts     register.Options
+	sync.RWMutex
 }
 
 // services is a KV map with service name as the key and a map of records as the value
@@ -59,7 +58,7 @@ func (m *memory) ttlPrune() {
 
 	for range prune.C {
 		m.Lock()
-		for domain, services := range m.records {
+		for namespace, services := range m.records {
 			for service, versions := range services {
 				for version, record := range versions {
 					for id, n := range record.Nodes {
@@ -67,7 +66,7 @@ func (m *memory) ttlPrune() {
 							if m.opts.Logger.V(logger.DebugLevel) {
 								m.opts.Logger.Debug(m.opts.Context, fmt.Sprintf("Register TTL expired for node %s of service %s", n.ID, service))
 							}
-							delete(m.records[domain][service][version].Nodes, id)
+							delete(m.records[namespace][service][version].Nodes, id)
 						}
 					}
 				}
@@ -100,11 +99,11 @@ func (m *memory) sendEvent(r *register.Result) {
 	}
 }
 
-func (m *memory) Connect(ctx context.Context) error {
+func (m *memory) Connect(_ context.Context) error {
 	return nil
 }
 
-func (m *memory) Disconnect(ctx context.Context) error {
+func (m *memory) Disconnect(_ context.Context) error {
 	return nil
 }
 
@@ -124,24 +123,19 @@ func (m *memory) Options() register.Options {
 	return m.opts
 }
 
-func (m *memory) Register(ctx context.Context, s *register.Service, opts ...register.RegisterOption) error {
+func (m *memory) Register(_ context.Context, s *register.Service, opts ...register.RegisterOption) error {
 	m.Lock()
 	defer m.Unlock()
 
 	options := register.NewRegisterOptions(opts...)
 
 	// get the services for this domain from the register
-	srvs, ok := m.records[options.Domain]
+	srvs, ok := m.records[options.Namespace]
 	if !ok {
 		srvs = make(services)
 	}
 
-	// domain is set in metadata so it can be passed to watchers
+	s.Namespace = options.Namespace
-	if s.Metadata == nil {
-		s.Metadata = map[string]string{"domain": options.Domain}
-	} else {
-		s.Metadata["domain"] = options.Domain
-	}
 
 	// ensure the service name exists
 	r := serviceToRecord(s, options.TTL)
@@ -154,8 +148,8 @@ func (m *memory) Register(ctx context.Context, s *register.Service, opts ...regi
 		if m.opts.Logger.V(logger.DebugLevel) {
 			m.opts.Logger.Debug(m.opts.Context, fmt.Sprintf("Register added new service: %s, version: %s", s.Name, s.Version))
 		}
-		m.records[options.Domain] = srvs
+		m.records[options.Namespace] = srvs
-		go m.sendEvent(&register.Result{Action: "create", Service: s})
+		go m.sendEvent(&register.Result{Action: register.EventCreate, Service: s})
 	}
 
 	var addedNodes bool
@@ -173,9 +167,6 @@ func (m *memory) Register(ctx context.Context, s *register.Service, opts ...regi
 			metadata[k] = v
 		}
 
-		// set the domain
-		metadata["domain"] = options.Domain
-
 		// add the node
 		srvs[s.Name][s.Version].Nodes[n.ID] = &node{
 			Node: &register.Node{
@@ -194,7 +185,7 @@ func (m *memory) Register(ctx context.Context, s *register.Service, opts ...regi
 		if m.opts.Logger.V(logger.DebugLevel) {
 			m.opts.Logger.Debug(m.opts.Context, fmt.Sprintf("Register added new node to service: %s, version: %s", s.Name, s.Version))
 		}
-		go m.sendEvent(&register.Result{Action: "update", Service: s})
+		go m.sendEvent(&register.Result{Action: register.EventUpdate, Service: s})
 	} else {
 		// refresh TTL and timestamp
 		for _, n := range s.Nodes {
@@ -206,7 +197,7 @@ func (m *memory) Register(ctx context.Context, s *register.Service, opts ...regi
 		}
 	}
 
-	m.records[options.Domain] = srvs
+	m.records[options.Namespace] = srvs
 	return nil
 }
 
@@ -216,15 +207,8 @@ func (m *memory) Deregister(ctx context.Context, s *register.Service, opts ...re
 
 	options := register.NewDeregisterOptions(opts...)
 
-	// domain is set in metadata so it can be passed to watchers
-	if s.Metadata == nil {
-		s.Metadata = map[string]string{"domain": options.Domain}
-	} else {
-		s.Metadata["domain"] = options.Domain
-	}
-
 	// if the domain doesn't exist, there is nothing to deregister
-	services, ok := m.records[options.Domain]
+	services, ok := m.records[options.Namespace]
 	if !ok {
 		return nil
 	}
@@ -253,16 +237,16 @@ func (m *memory) Deregister(ctx context.Context, s *register.Service, opts ...re
 	// if the nodes not empty, we replace the version in the store and exist, the rest of the logic
 	// is cleanup
 	if len(version.Nodes) > 0 {
-		m.records[options.Domain][s.Name][s.Version] = version
+		m.records[options.Namespace][s.Name][s.Version] = version
-		go m.sendEvent(&register.Result{Action: "update", Service: s})
+		go m.sendEvent(&register.Result{Action: register.EventUpdate, Service: s})
 		return nil
 	}
 
 	// if this version was the only version of the service, we can remove the whole service from the
 	// register and exit
 	if len(versions) == 1 {
-		delete(m.records[options.Domain], s.Name)
+		delete(m.records[options.Namespace], s.Name)
-		go m.sendEvent(&register.Result{Action: "delete", Service: s})
+		go m.sendEvent(&register.Result{Action: register.EventDelete, Service: s})
 
 		if m.opts.Logger.V(logger.DebugLevel) {
 			m.opts.Logger.Debug(m.opts.Context, fmt.Sprintf("Register removed service: %s", s.Name))
@@ -271,8 +255,8 @@ func (m *memory) Deregister(ctx context.Context, s *register.Service, opts ...re
 	}
 
 	// there are other versions of the service running, so only remove this version of it
-	delete(m.records[options.Domain][s.Name], s.Version)
+	delete(m.records[options.Namespace][s.Name], s.Version)
-	go m.sendEvent(&register.Result{Action: "delete", Service: s})
+	go m.sendEvent(&register.Result{Action: register.EventDelete, Service: s})
 	if m.opts.Logger.V(logger.DebugLevel) {
 		m.opts.Logger.Debug(m.opts.Context, fmt.Sprintf("Register removed service: %s, version: %s", s.Name, s.Version))
 	}
@@ -284,15 +268,15 @@ func (m *memory) LookupService(ctx context.Context, name string, opts ...registe
 	options := register.NewLookupOptions(opts...)
 
 	// if it's a wildcard domain, return from all domains
-	if options.Domain == register.WildcardDomain {
+	if options.Namespace == register.WildcardNamespace {
 		m.RLock()
 		recs := m.records
 		m.RUnlock()
 
 		var services []*register.Service
 
-		for domain := range recs {
+		for namespace := range recs {
-			srvs, err := m.LookupService(ctx, name, append(opts, register.LookupDomain(domain))...)
+			srvs, err := m.LookupService(ctx, name, append(opts, register.LookupNamespace(namespace))...)
 			if err == register.ErrNotFound {
 				continue
 			} else if err != nil {
@@ -311,7 +295,7 @@ func (m *memory) LookupService(ctx context.Context, name string, opts ...registe
 	defer m.RUnlock()
 
 	// check the domain exists
-	services, ok := m.records[options.Domain]
+	services, ok := m.records[options.Namespace]
 	if !ok {
 		return nil, register.ErrNotFound
 	}
@@ -328,7 +312,7 @@ func (m *memory) LookupService(ctx context.Context, name string, opts ...registe
 	var i int
 
 	for _, r := range versions {
-		result[i] = recordToService(r, options.Domain)
+		result[i] = recordToService(r, options.Namespace)
 		i++
 	}
 
@@ -339,15 +323,15 @@ func (m *memory) ListServices(ctx context.Context, opts ...register.ListOption)
 	options := register.NewListOptions(opts...)
 
 	// if it's a wildcard domain, list from all domains
-	if options.Domain == register.WildcardDomain {
+	if options.Namespace == register.WildcardNamespace {
 		m.RLock()
 		recs := m.records
 		m.RUnlock()
 
 		var services []*register.Service
 
-		for domain := range recs {
+		for namespace := range recs {
-			srvs, err := m.ListServices(ctx, append(opts, register.ListDomain(domain))...)
+			srvs, err := m.ListServices(ctx, append(opts, register.ListNamespace(namespace))...)
 			if err != nil {
 				return nil, err
 			}
@@ -361,7 +345,7 @@ func (m *memory) ListServices(ctx context.Context, opts ...register.ListOption)
 	defer m.RUnlock()
 
 	// ensure the domain exists
-	services, ok := m.records[options.Domain]
+	services, ok := m.records[options.Namespace]
 	if !ok {
 		return make([]*register.Service, 0), nil
 	}
@@ -371,7 +355,7 @@ func (m *memory) ListServices(ctx context.Context, opts ...register.ListOption)
 
 	for _, service := range services {
 		for _, version := range service {
-			result = append(result, recordToService(version, options.Domain))
+			result = append(result, recordToService(version, options.Namespace))
 		}
 	}
 
@@ -426,16 +410,13 @@ func (m *watcher) Next() (*register.Result, error) {
 				continue
 			}
 
-			// extract domain from service metadata
+			namespace := register.DefaultNamespace
-			var domain string
+			if r.Service.Namespace != "" {
-			if r.Service.Metadata != nil && len(r.Service.Metadata["domain"]) > 0 {
+				namespace = r.Service.Namespace
-				domain = r.Service.Metadata["domain"]
-			} else {
-				domain = register.DefaultDomain
 			}
 
 			// only send the event if watching the wildcard or this specific domain
-			if m.wo.Domain == register.WildcardDomain || m.wo.Domain == domain {
+			if m.wo.Namespace == register.WildcardNamespace || m.wo.Namespace == namespace {
 				return r, nil
 			}
 		case <-m.exit:
@@ -454,11 +435,6 @@ func (m *watcher) Stop() {
 }
 
 func serviceToRecord(s *register.Service, ttl time.Duration) *record {
-	metadata := make(map[string]string, len(s.Metadata))
-	for k, v := range s.Metadata {
-		metadata[k] = v
-	}
-
 	nodes := make(map[string]*node, len(s.Nodes))
 	for _, n := range s.Nodes {
 		nodes[n.ID] = &node{
@@ -468,44 +444,19 @@ func serviceToRecord(s *register.Service, ttl time.Duration) *record {
 		}
 	}
 
-	endpoints := make([]*register.Endpoint, len(s.Endpoints))
-	for i, e := range s.Endpoints {
-		endpoints[i] = e
-	}
-
 	return &record{
-		Name:      s.Name,
+		Name:    s.Name,
-		Version:   s.Version,
+		Version: s.Version,
-		Metadata:  metadata,
+		Nodes:   nodes,
-		Nodes:     nodes,
-		Endpoints: endpoints,
 	}
 }
 
-func recordToService(r *record, domain string) *register.Service {
+func recordToService(r *record, namespace string) *register.Service {
 	metadata := make(map[string]string, len(r.Metadata))
 	for k, v := range r.Metadata {
 		metadata[k] = v
 	}
 
-	// set the domain in metadata so it can be determined when a wildcard query is performed
-	metadata["domain"] = domain
-
-	endpoints := make([]*register.Endpoint, len(r.Endpoints))
-	for i, e := range r.Endpoints {
-		md := make(map[string]string, len(e.Metadata))
-		for k, v := range e.Metadata {
-			md[k] = v
-		}
-
-		endpoints[i] = &register.Endpoint{
-			Name:     e.Name,
-			Request:  e.Request,
-			Response: e.Response,
-			Metadata: md,
-		}
-	}
-
 	nodes := make([]*register.Node, len(r.Nodes))
 	i := 0
 	for _, n := range r.Nodes {
@@ -525,8 +476,7 @@ func recordToService(r *record, domain string) *register.Service {
 	return &register.Service{
 		Name:      r.Name,
 		Version:   r.Version,
-		Metadata:  metadata,
-		Endpoints: endpoints,
 		Nodes:     nodes,
+		Namespace: namespace,
 	}
 }

register/memory/memory_test.go

@@ -208,9 +208,9 @@ func TestMemoryRegistryTTLConcurrent(t *testing.T) {
 		}
 	}
 
-	//if len(os.Getenv("IN_TRAVIS_CI")) == 0 {
+	// if len(os.Getenv("IN_TRAVIS_CI")) == 0 {
 	//	t.Logf("test will wait %v, then check TTL timeouts", waitTime)
-	//}
+	// }
 
 	errChan := make(chan error, concurrency)
 	syncChan := make(chan struct{})
@@ -253,32 +253,32 @@ func TestMemoryWildcard(t *testing.T) {
 
 	testSrv := &register.Service{Name: "foo", Version: "1.0.0"}
 
-	if err := m.Register(ctx, testSrv, register.RegisterDomain("one")); err != nil {
+	if err := m.Register(ctx, testSrv, register.RegisterNamespace("one")); err != nil {
 		t.Fatalf("Register err: %v", err)
 	}
-	if err := m.Register(ctx, testSrv, register.RegisterDomain("two")); err != nil {
+	if err := m.Register(ctx, testSrv, register.RegisterNamespace("two")); err != nil {
 		t.Fatalf("Register err: %v", err)
 	}
 
-	if recs, err := m.ListServices(ctx, register.ListDomain("one")); err != nil {
+	if recs, err := m.ListServices(ctx, register.ListNamespace("one")); err != nil {
 		t.Errorf("List err: %v", err)
 	} else if len(recs) != 1 {
 		t.Errorf("Expected 1 record, got %v", len(recs))
 	}
 
-	if recs, err := m.ListServices(ctx, register.ListDomain("*")); err != nil {
+	if recs, err := m.ListServices(ctx, register.ListNamespace("*")); err != nil {
 		t.Errorf("List err: %v", err)
 	} else if len(recs) != 2 {
 		t.Errorf("Expected 2 records, got %v", len(recs))
 	}
 
-	if recs, err := m.LookupService(ctx, testSrv.Name, register.LookupDomain("one")); err != nil {
+	if recs, err := m.LookupService(ctx, testSrv.Name, register.LookupNamespace("one")); err != nil {
 		t.Errorf("Lookup err: %v", err)
 	} else if len(recs) != 1 {
 		t.Errorf("Expected 1 record, got %v", len(recs))
 	}
 
-	if recs, err := m.LookupService(ctx, testSrv.Name, register.LookupDomain("*")); err != nil {
+	if recs, err := m.LookupService(ctx, testSrv.Name, register.LookupNamespace("*")); err != nil {
 		t.Errorf("Lookup err: %v", err)
 	} else if len(recs) != 2 {
 		t.Errorf("Expected 2 records, got %v", len(recs))
@@ -290,27 +290,29 @@ func TestWatcher(t *testing.T) {
 
 	ctx := context.TODO()
 	m := NewRegister()
-	m.Init()
+	if err := m.Init(); err != nil {
-	m.Connect(ctx)
+		t.Fatal(err)
+	}
+	if err := m.Connect(ctx); err != nil {
+		t.Fatal(err)
+	}
 	wc, err := m.Watch(ctx)
 	if err != nil {
 		t.Fatalf("cant watch: %v", err)
 	}
 	defer wc.Stop()
 
+	cherr := make(chan error, 10)
 	var wg sync.WaitGroup
 	wg.Add(1)
 	go func() {
-		for {
+		_, err := wc.Next()
-			_, err := wc.Next()
+		if err != nil {
-			if err != nil {
+			cherr <- fmt.Errorf("unexpected err %v", err)
-				t.Fatal("unexpected err", err)
-			}
-			// t.Logf("changes %#+v", ch.Service)
-			wc.Stop()
-			wg.Done()
-			return
 		}
+		// t.Logf("changes %#+v", ch.Service)
+		wc.Stop()
+		wg.Done()
 	}()
 
 	if err := m.Register(ctx, testSrv); err != nil {

register/options.go

@@ -5,6 +5,7 @@ import (
 	"crypto/tls"
 	"time"
 
+	"go.unistack.org/micro/v3/codec"
 	"go.unistack.org/micro/v3/logger"
 	"go.unistack.org/micro/v3/meter"
 	"go.unistack.org/micro/v3/tracer"
@@ -26,6 +27,8 @@ type Options struct {
 	Name string
 	// Addrs specifies register addrs
 	Addrs []string
+	// Codec used to marshal/unmarshal data in register
+	Codec codec.Codec
 	// Timeout specifies timeout
 	Timeout time.Duration
 }
@@ -37,6 +40,7 @@ func NewOptions(opts ...Option) Options {
 		Meter:   meter.DefaultMeter,
 		Tracer:  tracer.DefaultTracer,
 		Context: context.Background(),
+		Codec:   codec.NewCodec(),
 	}
 	for _, o := range opts {
 		o(&options)
@@ -46,17 +50,17 @@ func NewOptions(opts ...Option) Options {
 
 // RegisterOptions holds options for register method
 type RegisterOptions struct { // nolint: golint,revive
-	Context  context.Context
+	Context   context.Context
-	Domain   string
+	Namespace string
-	TTL      time.Duration
+	TTL       time.Duration
-	Attempts int
+	Attempts  int
 }
 
 // NewRegisterOptions returns register options struct filled by opts
 func NewRegisterOptions(opts ...RegisterOption) RegisterOptions {
 	options := RegisterOptions{
-		Domain:  DefaultDomain,
+		Namespace: DefaultNamespace,
-		Context: context.Background(),
+		Context:   context.Background(),
 	}
 	for _, o := range opts {
 		o(&options)
@@ -72,15 +76,15 @@ type WatchOptions struct {
 	// Other options for implementations of the interface
 	// can be stored in a context
 	Context context.Context
-	// Domain to watch
+	// Namespace to watch
-	Domain string
+	Namespace string
 }
 
 // NewWatchOptions returns watch options filled by opts
 func NewWatchOptions(opts ...WatchOption) WatchOptions {
 	options := WatchOptions{
-		Domain:  DefaultDomain,
+		Namespace: DefaultNamespace,
-		Context: context.Background(),
+		Context:   context.Background(),
 	}
 	for _, o := range opts {
 		o(&options)
@@ -91,8 +95,8 @@ func NewWatchOptions(opts ...WatchOption) WatchOptions {
 // DeregisterOptions holds options for deregister method
 type DeregisterOptions struct {
 	Context context.Context
-	// Domain the service was registered in
+	// Namespace the service was registered in
-	Domain string
+	Namespace string
 	// Atempts specify max attempts for deregister
 	Attempts int
 }
@@ -100,8 +104,8 @@ type DeregisterOptions struct {
 // NewDeregisterOptions returns options for deregister filled by opts
 func NewDeregisterOptions(opts ...DeregisterOption) DeregisterOptions {
 	options := DeregisterOptions{
-		Domain:  DefaultDomain,
+		Namespace: DefaultNamespace,
-		Context: context.Background(),
+		Context:   context.Background(),
 	}
 	for _, o := range opts {
 		o(&options)
@@ -112,15 +116,15 @@ func NewDeregisterOptions(opts ...DeregisterOption) DeregisterOptions {
 // LookupOptions holds lookup options
 type LookupOptions struct {
 	Context context.Context
-	// Domain to scope the request to
+	// Namespace to scope the request to
-	Domain string
+	Namespace string
 }
 
 // NewLookupOptions returns lookup options filled by opts
 func NewLookupOptions(opts ...LookupOption) LookupOptions {
 	options := LookupOptions{
-		Domain:  DefaultDomain,
+		Namespace: DefaultNamespace,
-		Context: context.Background(),
+		Context:   context.Background(),
 	}
 	for _, o := range opts {
 		o(&options)
@@ -130,16 +134,17 @@ func NewLookupOptions(opts ...LookupOption) LookupOptions {
 
 // ListOptions holds the list options for list method
 type ListOptions struct {
+	// Context used to store additional options
 	Context context.Context
-	// Domain to scope the request to
+	// Namespace to scope the request to
-	Domain string
+	Namespace string
 }
 
 // NewListOptions returns list options filled by opts
 func NewListOptions(opts ...ListOption) ListOptions {
 	options := ListOptions{
-		Domain:  DefaultDomain,
+		Namespace: DefaultNamespace,
-		Context: context.Background(),
+		Context:   context.Background(),
 	}
 	for _, o := range opts {
 		o(&options)
@@ -217,10 +222,10 @@ func RegisterContext(ctx context.Context) RegisterOption { // nolint: golint,rev
 	}
 }
 
-// RegisterDomain secifies register domain
+// RegisterNamespace secifies register Namespace
-func RegisterDomain(d string) RegisterOption { // nolint: golint,revive
+func RegisterNamespace(d string) RegisterOption { // nolint: golint,revive
 	return func(o *RegisterOptions) {
-		o.Domain = d
+		o.Namespace = d
 	}
 }
 
@@ -238,10 +243,10 @@ func WatchContext(ctx context.Context) WatchOption {
 	}
 }
 
-// WatchDomain sets the domain for watch
+// WatchNamespace sets the Namespace for watch
-func WatchDomain(d string) WatchOption {
+func WatchNamespace(d string) WatchOption {
 	return func(o *WatchOptions) {
-		o.Domain = d
+		o.Namespace = d
 	}
 }
 
@@ -259,10 +264,10 @@ func DeregisterContext(ctx context.Context) DeregisterOption {
 	}
 }
 
-// DeregisterDomain specifies deregister domain
+// DeregisterNamespace specifies deregister Namespace
-func DeregisterDomain(d string) DeregisterOption {
+func DeregisterNamespace(d string) DeregisterOption {
 	return func(o *DeregisterOptions) {
-		o.Domain = d
+		o.Namespace = d
 	}
 }
 
@@ -273,10 +278,10 @@ func LookupContext(ctx context.Context) LookupOption {
 	}
 }
 
-// LookupDomain sets the domain for lookup
+// LookupNamespace sets the Namespace for lookup
-func LookupDomain(d string) LookupOption {
+func LookupNamespace(d string) LookupOption {
 	return func(o *LookupOptions) {
-		o.Domain = d
+		o.Namespace = d
 	}
 }
 
@@ -287,10 +292,10 @@ func ListContext(ctx context.Context) ListOption {
 	}
 }
 
-// ListDomain sets the domain for list method
+// ListNamespace sets the Namespace for list method
-func ListDomain(d string) ListOption {
+func ListNamespace(d string) ListOption {
 	return func(o *ListOptions) {
-		o.Domain = d
+		o.Namespace = d
 	}
 }
 
@@ -300,3 +305,9 @@ func Name(n string) Option {
 		o.Name = n
 	}
 }
+
+func Codec(c codec.Codec) Option {
+	return func(o *Options) {
+		o.Codec = c
+	}
+}

register/register.go

@@ -9,16 +9,16 @@ import (
 )
 
 const (
-	// WildcardDomain indicates any domain
+	// WildcardNamespace indicates any Namespace
-	WildcardDomain = "*"
+	WildcardNamespace = "*"
 )
 
-// DefaultDomain to use if none was provided in options
+// DefaultNamespace to use if none was provided in options
-var DefaultDomain = "micro"
+var DefaultNamespace = "micro"
 
 var (
 	// DefaultRegister is the global default register
-	DefaultRegister Register = NewRegister()
+	DefaultRegister = NewRegister()
 	// ErrNotFound returned when LookupService is called and no services found
 	ErrNotFound = errors.New("service not found")
 	// ErrWatcherStopped returned when when watcher is stopped
@@ -29,41 +29,47 @@ var (
 // and an abstraction over varying implementations
 // {consul, etcd, zookeeper, ...}
 type Register interface {
+	// Name returns register name
 	Name() string
+	// Init initialize register
 	Init(...Option) error
+	// Options returns options for register
 	Options() Options
+	// Connect initialize connect to register
 	Connect(context.Context) error
+	// Disconnect initialize discconection from register
 	Disconnect(context.Context) error
+	// Register service in registry
 	Register(context.Context, *Service, ...RegisterOption) error
+	// Deregister service from registry
 	Deregister(context.Context, *Service, ...DeregisterOption) error
+	// LookupService in registry
 	LookupService(context.Context, string, ...LookupOption) ([]*Service, error)
+	// ListServices in registry
 	ListServices(context.Context, ...ListOption) ([]*Service, error)
+	// Watch registry events
 	Watch(context.Context, ...WatchOption) (Watcher, error)
+	// String returns registry string representation
 	String() string
+	// Live returns register liveness
+	// Live() bool
+	// Ready returns register readiness
+	// Ready() bool
 }
 
 // Service holds service register info
 type Service struct {
-	Name      string            `json:"name"`
+	Name      string  `json:"name,omitempty"`
-	Version   string            `json:"version"`
+	Version   string  `json:"version,omitempty"`
-	Metadata  metadata.Metadata `json:"metadata"`
+	Nodes     []*Node `json:"nodes,omitempty"`
-	Endpoints []*Endpoint       `json:"endpoints"`
+	Namespace string  `json:"namespace,omitempty"`
-	Nodes     []*Node           `json:"nodes"`
 }
 
 // Node holds node register info
 type Node struct {
-	Metadata metadata.Metadata `json:"metadata"`
+	Metadata metadata.Metadata `json:"metadata,omitempty"`
-	ID       string            `json:"id"`
+	ID       string            `json:"id,omitempty"`
-	Address  string            `json:"address"`
+	Address  string            `json:"address,omitempty"`
-}
-
-// Endpoint holds endpoint register info
-type Endpoint struct {
-	Request  string            `json:"request"`
-	Response string            `json:"response"`
-	Metadata metadata.Metadata `json:"metadata"`
-	Name     string            `json:"name"`
 }
 
 // Option func signature

register/watcher.go

@@ -15,31 +15,31 @@ type Watcher interface {
 // the watcher. Actions can be create, update, delete
 type Result struct {
 	// Service holds register service
-	Service *Service
+	Service *Service `json:"service,omitempty"`
 	// Action holds the action
-	Action string
+	Action EventType `json:"action,omitempty"`
 }
 
 // EventType defines register event type
 type EventType int
 
 const (
-	// Create is emitted when a new service is registered
+	// EventCreate is emitted when a new service is registered
-	Create EventType = iota
+	EventCreate EventType = iota
-	// Delete is emitted when an existing service is deregistered
+	// EventDelete is emitted when an existing service is deregistered
-	Delete
+	EventDelete
-	// Update is emitted when an existing service is updated
+	// EventUpdate is emitted when an existing service is updated
-	Update
+	EventUpdate
 )
 
 // String returns human readable event type
 func (t EventType) String() string {
 	switch t {
-	case Create:
+	case EventCreate:
 		return "create"
-	case Delete:
+	case EventDelete:
 		return "delete"
-	case Update:
+	case EventUpdate:
 		return "update"
 	default:
 		return "unknown"
@@ -49,11 +49,11 @@ func (t EventType) String() string {
 // Event is register event
 type Event struct {
 	// Timestamp is event timestamp
-	Timestamp time.Time
+	Timestamp time.Time `json:"timestamp,omitempty"`
 	// Service is register service
-	Service *Service
+	Service *Service `json:"service,omitempty"`
 	// ID is register id
-	ID string
+	ID string `json:"id,omitempty"`
 	// Type defines type of event
-	Type EventType
+	Type EventType `json:"type,omitempty"`
 }

resolver/dns/dns.go

@@ -12,9 +12,9 @@ import (
 
 // Resolver is a DNS network resolve
 type Resolver struct {
-	sync.RWMutex
 	goresolver *net.Resolver
 	Address    string
+	mu         sync.RWMutex
 }
 
 // Resolve tries to resolve endpoint address
@@ -39,12 +39,12 @@ func (r *Resolver) Resolve(name string) ([]*resolver.Record, error) {
 		return []*resolver.Record{rec}, nil
 	}
 
-	r.RLock()
+	r.mu.RLock()
 	goresolver := r.goresolver
-	r.RUnlock()
+	r.mu.RUnlock()
 
 	if goresolver == nil {
-		r.Lock()
+		r.mu.Lock()
 		r.goresolver = &net.Resolver{
 			Dial: func(ctx context.Context, _ string, _ string) (net.Conn, error) {
 				d := net.Dialer{
@@ -53,7 +53,7 @@ func (r *Resolver) Resolve(name string) ([]*resolver.Record, error) {
 				return d.DialContext(ctx, "udp", r.Address)
 			},
 		}
-		r.Unlock()
+		r.mu.Unlock()
 	}
 
 	addrs, err := goresolver.LookupIP(context.TODO(), "ip", host)