Merge pull request 'add providers interface' (#43) from providers into master

Reviewed-on: #43

.drone.yml

@@ -1,20 +0,0 @@
-kind: pipeline
-name: default
-
-environment:
-  VAULT_DEV_LISTEN_ADDRESS: http://vault:8200
-  VAULT_DEV_ROOT_TOKEN_ID: dev
-  FDEVS_CONFIG_ETCD_HOST: etcd:2379
-
-steps:
-- name: test 
-  image: golang
-  commands:
-  # - go test -parallel 10 -race ./... 
-  # - go test -race ./... 
-  - go test ./... 
-
-- name: golangci-lint
-  image: golangci/golangci-lint:v1.55
-  commands:
-  - golangci-lint run

.gitea/workflows/dasel.yml

@@ -0,0 +1,38 @@
+name: Go Action 
+
+on:
+  push:
+    branches:
+      - master
+    paths:
+      - 'provider/dasel/**'
+      - '.gitea/workflows/dasel.yml'
+  pull_request:
+    paths:
+      - 'provider/dasel/**'
+      - '.gitea/workflows/dasel.yml'
+
+jobs:
+  goaction:
+    runs-on: ubuntu-latest # Use a Gitea Actions runner label
+    steps:
+      - name: Check out repository code
+        uses: actions/checkout@v4 # Action to clone the repo
+
+      - name: Set up Go
+        uses: actions/setup-go@v5 # Action to install a specific Go version
+        with:
+          go-version: '1.25.5' # Specify your required Go version
+      
+      - name: Run golangci-lint
+        uses: golangci/golangci-lint-action@v8 # Use the golangci-lint action
+        with:
+          version: v2.7.2 # Specify the linter version
+          # Optional: additional arguments
+          args: --verbose
+          working-directory: ./provider/dasel 
+
+      - name: Run go test
+        run: go test ./...
+        working-directory: ./provider/dasel
+

.gitea/workflows/etcd.yml

@@ -0,0 +1,50 @@
+name: Go Action 
+
+on:
+  push:
+    branches:
+      - master
+    paths:
+      - 'provider/etcd/**'
+      - '.gitea/workflows/etcd.yml'
+  pull_request:
+    paths:
+      - 'provider/etcd/**'
+      - '.gitea/workflows/etcd.yml'
+
+jobs:
+  goaction:
+    runs-on: ubuntu-latest # Use a Gitea Actions runner label
+    services:
+      # The label "etcd-server" becomes the hostname for the service.
+      etcd-server:
+        # Use the official etcd Docker image
+        image: quay.io/coreos/etcd:v3.6.7
+        env:
+          ETCD_LISTEN_CLIENT_URLS: http://0.0.0.0:2379 
+          ETCD_ADVERTISE_CLIENT_URLS: http://etcd-server:2379 
+
+    env:
+      FDEVS_CONFIG_ETCD_HOST: 'etcd-server:2379'
+
+    steps:
+      - name: Check out repository code
+        uses: actions/checkout@v4 # Action to clone the repo
+
+      - name: Set up Go
+        uses: actions/setup-go@v5 # Action to install a specific Go version
+        with:
+          go-version: '1.25.5' # Specify your required Go version
+      
+      - name: Run golangci-lint
+        uses: golangci/golangci-lint-action@v8 # Use the golangci-lint action
+        with:
+          version: v2.7.2 # Specify the linter version
+          # Optional: additional arguments
+          args: --verbose
+          working-directory: ./provider/etcd 
+
+      - name: Run go test
+        run: go test ./...
+        working-directory: ./provider/etcd
+

.gitea/workflows/goaction.yml

@@ -0,0 +1,47 @@
+name: Go Action 
+
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+    paths-ignore:
+      - 'provider/etcd/**'
+      - '.gitea/workflows/etcd.yml'
+      - 'provider/ini/**'
+      - '.gitea/workflows/ini.yml'
+      - 'provider/json/**'
+      - '.gitea/workflows/json.yml'
+      - 'provider/toml/**'
+      - '.gitea/workflows/toml.yml'
+      - 'provider/vault/**'
+      - '.gitea/workflows/vault.yml'
+      - 'provider/yaml/**'
+      - '.gitea/workflows/yaml.yml'
+      - 'provider/dasel/**'
+      - '.gitea/workflows/dasel.yml'
+
+
+
+jobs:
+  goaction:
+    runs-on: ubuntu-latest # Use a Gitea Actions runner label
+    steps:
+      - name: Check out repository code
+        uses: actions/checkout@v4 # Action to clone the repo
+
+      - name: Set up Go
+        uses: actions/setup-go@v5 # Action to install a specific Go version
+        with:
+          go-version: '1.25.5' # Specify your required Go version
+
+      - name: Run golangci-lint
+        uses: golangci/golangci-lint-action@v8 # Use the golangci-lint action
+        with:
+          version: v2.7.2 # Specify the linter version
+          # Optional: additional arguments
+          args: --verbose
+
+      - name: Run go test
+        run: go test ./...
+

.gitea/workflows/ini.yml

@@ -0,0 +1,38 @@
+name: Go Action 
+
+on:
+  push:
+    branches:
+      - master
+    paths:
+      - 'provider/ini/**'
+      - '.gitea/workflows/ini.yml'
+  pull_request:
+    paths:
+      - 'provider/ini/**'
+      - '.gitea/workflows/ini.yml'
+
+jobs:
+  goaction:
+    runs-on: ubuntu-latest # Use a Gitea Actions runner label
+    steps:
+      - name: Check out repository code
+        uses: actions/checkout@v4 # Action to clone the repo
+
+      - name: Set up Go
+        uses: actions/setup-go@v5 # Action to install a specific Go version
+        with:
+          go-version: '1.25.5' # Specify your required Go version
+      
+      - name: Run golangci-lint
+        uses: golangci/golangci-lint-action@v8 # Use the golangci-lint action
+        with:
+          version: v2.7.2 # Specify the linter version
+          # Optional: additional arguments
+          args: --verbose
+          working-directory: ./provider/ini 
+
+      - name: Run go test
+        run: go test ./...
+        working-directory: ./provider/ini
+

.gitea/workflows/json.yml

@@ -0,0 +1,38 @@
+name: Go Action 
+
+on:
+  push:
+    branches:
+      - master
+    paths:
+      - 'provider/json/**'
+      - '.gitea/workflows/json.yml'
+  pull_request:
+    paths:
+      - 'provider/json/**'
+      - '.gitea/workflows/json.yml'
+
+jobs:
+  goaction:
+    runs-on: ubuntu-latest # Use a Gitea Actions runner label
+    steps:
+      - name: Check out repository code
+        uses: actions/checkout@v4 # Action to clone the repo
+
+      - name: Set up Go
+        uses: actions/setup-go@v5 # Action to install a specific Go version
+        with:
+          go-version: '1.25.5' # Specify your required Go version
+      
+      - name: Run golangci-lint
+        uses: golangci/golangci-lint-action@v8 # Use the golangci-lint action
+        with:
+          version: v2.7.2 # Specify the linter version
+          # Optional: additional arguments
+          args: --verbose
+          working-directory: ./provider/json 
+
+      - name: Run go test
+        run: go test ./...
+        working-directory: ./provider/json
+

.gitea/workflows/toml.yml

@@ -0,0 +1,38 @@
+name: Go Action 
+
+on:
+  push:
+    branches:
+      - master
+    paths:
+      - 'provider/toml/**'
+      - '.gitea/workflows/toml.yml'
+  pull_request:
+    paths:
+      - 'provider/toml/**'
+      - '.gitea/workflows/toml.yml'
+
+jobs:
+  goaction:
+    runs-on: ubuntu-latest # Use a Gitea Actions runner label
+    steps:
+      - name: Check out repository code
+        uses: actions/checkout@v4 # Action to clone the repo
+
+      - name: Set up Go
+        uses: actions/setup-go@v5 # Action to install a specific Go version
+        with:
+          go-version: '1.25.5' # Specify your required Go version
+      
+      - name: Run golangci-lint
+        uses: golangci/golangci-lint-action@v8 # Use the golangci-lint action
+        with:
+          version: v2.7.2 # Specify the linter version
+          # Optional: additional arguments
+          args: --verbose
+          working-directory: ./provider/toml 
+
+      - name: Run go test
+        run: go test ./...
+        working-directory: ./provider/toml
+

.gitea/workflows/vault.yml

@@ -0,0 +1,46 @@
+name: Go Action 
+
+on:
+  push:
+    branches:
+      - master
+    paths:
+      - 'provider/vault/**'
+      - '.gitea/workflows/vault.yml'
+  pull_request:
+    paths:
+      - 'provider/vault/**'
+      - '.gitea/workflows/vault.yml'
+
+jobs:
+  goaction:
+    services:
+      vault-server:
+        image: vault:1.13.3
+        env:
+          VAULT_DEV_ROOT_TOKEN_ID: "dev"
+    env:
+      VAULT_DEV_LISTEN_ADDRESS: 'http://vault-server:8200'
+
+    runs-on: ubuntu-latest # Use a Gitea Actions runner label
+    steps:
+      - name: Check out repository code
+        uses: actions/checkout@v4 # Action to clone the repo
+
+      - name: Set up Go
+        uses: actions/setup-go@v5 # Action to install a specific Go version
+        with:
+          go-version: '1.25.5' # Specify your required Go version
+      
+      - name: Run golangci-lint
+        uses: golangci/golangci-lint-action@v8 # Use the golangci-lint action
+        with:
+          version: v2.7.2 # Specify the linter version
+          # Optional: additional arguments
+          args: --verbose
+          working-directory: ./provider/vault 
+
+      - name: Run go test
+        run: go test ./...
+        working-directory: ./provider/vault
+

.gitea/workflows/yaml.yml

@@ -0,0 +1,38 @@
+name: Go Action 
+
+on:
+  push:
+    branches:
+      - master
+    paths:
+      - 'provider/yaml/**'
+      - '.gitea/workflows/yaml.yml'
+  pull_request:
+    paths:
+      - 'provider/yaml/**'
+      - '.gitea/workflows/yaml.yml'
+
+jobs:
+  goaction:
+    runs-on: ubuntu-latest # Use a Gitea Actions runner label
+    steps:
+      - name: Check out repository code
+        uses: actions/checkout@v4 # Action to clone the repo
+
+      - name: Set up Go
+        uses: actions/setup-go@v5 # Action to install a specific Go version
+        with:
+          go-version: '1.25.5' # Specify your required Go version
+      
+      - name: Run golangci-lint
+        uses: golangci/golangci-lint-action@v8 # Use the golangci-lint action
+        with:
+          version: v2.7.2 # Specify the linter version
+          # Optional: additional arguments
+          args: --verbose
+          working-directory: ./provider/yaml
+
+      - name: Run go test
+        run: go test ./...
+        working-directory: ./provider/yaml
+

.golangci.yml

@@ -1,7 +1,20 @@
-run:
-  timeout: 5m
-
-linters-settings:
+version: "2"
+linters:
+  default: all
+  disable:
+    - noinlineerr
+    - depguard
+    - ireturn
+    - gochecknoglobals
+    # deprecated
+    - wsl
+  settings:
+    recvcheck:
+      disable-builtin: true
+      exclusions:
+        - "*.String"
+    funcorder:
+      constructor: false
     dupl:
       threshold: 100
     funlen:
@@ -10,57 +23,60 @@ linters-settings:
     goconst:
       min-len: 2
       min-occurrences: 2
+    cyclop:
+      max-complexity: 15
     gocyclo:
       min-complexity: 15
-    golint:
-      min-confidence: 0
-    govet:
-      check-shadowing: true
     lll:
       line-length: 140
-    maligned:
-      suggest-new: true
     misspell:
-      locale: US  
+      locale: US
     varnamelen:
       min-name-length: 2
-
-linters:
-    enable-all: true
-    disable:
-      - exhaustivestruct
-      - maligned
-      - interfacer
-      - scopelint
-      - exhaustruct
-      - depguard
-      - nolintlint
-      #deprecated
-      - structcheck
-      - varcheck
-      - golint
-      - deadcode
-      - ifshort
-      - nosnakecase
-
-      - ireturn # implement provider interface
-
-issues:
-  # Excluding configuration per-path, per-linter, per-text and per-source
-  exclude-rules:
-    - path: _test\.go
-      linters:
-        - gomnd
-        - exhaustivestruct
-        - wrapcheck
-        - exhaustruct
-        - varnamelen
-        - tenv
-        - funlen
-    - path: test/*
-      linters:
-        - gomnd
-        - exhaustivestruct
-        - wrapcheck
-        - exhaustruct
-        - varnamelen
+      ignore-decls:
+        - w io.Writer
+        - t testing.T
+        - e error
+        - i int
+        - b bytes.Buffer
+        - h Handle
+  exclusions:
+    generated: lax
+    presets:
+      - comments
+      - common-false-positives
+      - legacy
+      - std-error-handling
+    rules:
+      - linters:
+          - exhaustivestruct
+          - exhaustruct
+          - funlen
+          - mnd
+          - tenv
+          - varnamelen
+          - wrapcheck
+        path: _test\.go
+      - linters:
+          - exhaustivestruct
+          - exhaustruct
+          - mnd
+          - varnamelen
+          - wrapcheck
+        path: test/*
+    paths:
+      - third_party$
+      - builtin$
+      - examples$
+formatters:
+  enable:
+    - gci
+    - gofmt
+    - gofumpt
+    - goimports
+  exclusions:
+    generated: lax
+    paths:
+      - third_party$
+      - builtin$
+      - examples$

README.md

@@ -1,5 +1,5 @@
 # config
 
-[![Build Status](https://drone.gitoa.ru/api/badges/go-4devs/cache/status.svg)](https://drone.gitoa.ru/go-4devs/config)
+![Build Status](https://gitoa.ru/go-4devs/config/actions/workflows/goaction.yml/badge.svg)
 [![Go Report Card](https://goreportcard.com/badge/gitoa.ru/go-4devs/config)](https://goreportcard.com/report/gitoa.ru/go-4devs/config)
 [![GoDoc](https://godoc.org/gitoa.ru/go-4devs/config?status.svg)](http://godoc.org/gitoa.ru/go-4devs/config)

client.go

@@ -4,11 +4,11 @@ import (
 	"context"
 	"errors"
 	"fmt"
-	"sync"
-	"sync/atomic"
 )
 
-func Must(providers ...interface{}) *Client {
+var _ Providers = (*Client)(nil)
+
+func Must(providers ...any) *Client {
 	client, err := New(providers...)
 	if err != nil {
 		panic(err)
@@ -17,85 +17,40 @@ func Must(providers ...interface{}) *Client {
 	return client
 }
 
-func New(providers ...interface{}) (*Client, error) {
+func New(providers ...any) (*Client, error) {
 	client := &Client{
 		providers: make([]Provider, len(providers)),
+		name:      make(map[string]int),
+		chain:     make([]Providers, 0, len(providers)),
 	}
 
 	for idx, prov := range providers {
+		var name string
+
 		switch current := prov.(type) {
 		case Provider:
 			client.providers[idx] = current
+			name = current.Name()
 		case Factory:
-			client.providers[idx] = &provider{
-				factory: func(ctx context.Context) (Provider, error) {
-					return current(ctx, client)
-				},
-			}
+			client.providers[idx] = WrapFactory(current, client)
+			name = current.Name()
 		default:
 			return nil, fmt.Errorf("provier[%d]: %w %T", idx, ErrUnknowType, prov)
 		}
+
+		client.name[name] = idx
+		if current, ok := prov.(Providers); ok {
+			client.chain = append(client.chain, current)
+		}
 	}
 
 	return client, nil
 }
 
-type provider struct {
-	mu       sync.Mutex
-	done     uint32
-	provider Provider
-	factory  func(ctx context.Context) (Provider, error)
-}
-
-func (p *provider) init(ctx context.Context) error {
-	if atomic.LoadUint32(&p.done) == 0 {
-		if !p.mu.TryLock() {
-			return fmt.Errorf("%w", ErrInitFactory)
-		}
-		defer atomic.StoreUint32(&p.done, 1)
-		defer p.mu.Unlock()
-
-		var err error
-		if p.provider, err = p.factory(ctx); err != nil {
-			return fmt.Errorf("init provider factory:%w", err)
-		}
-	}
-
-	return nil
-}
-
-func (p *provider) Watch(ctx context.Context, callback WatchCallback, path ...string) error {
-	if err := p.init(ctx); err != nil {
-		return fmt.Errorf("init read:%w", err)
-	}
-
-	watch, ok := p.provider.(WatchProvider)
-	if !ok {
-		return nil
-	}
-
-	if err := watch.Watch(ctx, callback, path...); err != nil {
-		return fmt.Errorf("factory provider: %w", err)
-	}
-
-	return nil
-}
-
-func (p *provider) Value(ctx context.Context, path ...string) (Value, error) {
-	if err := p.init(ctx); err != nil {
-		return nil, fmt.Errorf("init read:%w", err)
-	}
-
-	variable, err := p.provider.Value(ctx, path...)
-	if err != nil {
-		return nil, fmt.Errorf("factory provider: %w", err)
-	}
-
-	return variable, nil
-}
-
 type Client struct {
 	providers []Provider
+	name      map[string]int
+	chain     []Providers
 }
 
 func (c *Client) Name() string {
@@ -111,7 +66,7 @@ func (c *Client) Value(ctx context.Context, path ...string) (Value, error) {
 
 	for _, provider := range c.providers {
 		value, err = provider.Value(ctx, path...)
-		if err == nil || !(errors.Is(err, ErrValueNotFound) || errors.Is(err, ErrInitFactory)) {
+		if err == nil || (!errors.Is(err, ErrNotFound) && !errors.Is(err, ErrInitFactory)) {
 			break
 		}
 	}
@@ -132,7 +87,7 @@ func (c *Client) Watch(ctx context.Context, callback WatchCallback, path ...stri
 
 		err := provider.Watch(ctx, callback, path...)
 		if err != nil {
-			if errors.Is(err, ErrValueNotFound) || errors.Is(err, ErrInitFactory) {
+			if errors.Is(err, ErrNotFound) || errors.Is(err, ErrInitFactory) {
 				continue
 			}
 
@@ -142,3 +97,45 @@ func (c *Client) Watch(ctx context.Context, callback WatchCallback, path ...stri
 
 	return nil
 }
+
+func (c *Client) Bind(ctx context.Context, data Variables) error {
+	for idx, prov := range c.providers {
+		provider, ok := prov.(BindProvider)
+		if !ok {
+			continue
+		}
+
+		if err := provider.Bind(ctx, data); err != nil {
+			return fmt.Errorf("bind[%d] %v:%w", idx, provider.Name(), err)
+		}
+	}
+
+	return nil
+}
+
+func (c *Client) Provider(name string) (Provider, error) {
+	if idx, ok := c.name[name]; ok {
+		return c.providers[idx], nil
+	}
+
+	for _, prov := range c.chain {
+		if cprov, err := prov.Provider(name); err == nil {
+			return cprov, nil
+		}
+	}
+
+	return nil, fmt.Errorf("provider[%v]:%w", c.Name(), ErrNotFound)
+}
+
+func (c *Client) Names() []string {
+	names := make([]string, 0, len(c.providers))
+	for name := range c.name {
+		names = append(names, name)
+	}
+
+	for _, prov := range c.chain {
+		names = append(names, prov.Names()...)
+	}
+
+	return names
+}

client_example_test.go

@@ -0,0 +1,175 @@
+package config_test
+
+import (
+	"context"
+	"fmt"
+	"log"
+	"os"
+	"sync"
+	"time"
+
+	"gitoa.ru/go-4devs/config"
+	"gitoa.ru/go-4devs/config/provider/arg"
+	"gitoa.ru/go-4devs/config/provider/env"
+	"gitoa.ru/go-4devs/config/provider/factory"
+	"gitoa.ru/go-4devs/config/provider/watcher"
+	"gitoa.ru/go-4devs/config/test"
+)
+
+func ExampleClient_Value() {
+	ctx := context.Background()
+	_ = os.Setenv("FDEVS_CONFIG_LISTEN", "8080")
+	_ = os.Setenv("FDEVS_CONFIG_HOST", "localhost")
+
+	args := os.Args
+
+	defer func() {
+		os.Args = args
+	}()
+
+	os.Args = []string{"main.go", "--host=gitoa.ru"}
+
+	// read json config
+
+	config, err := config.New(
+		arg.New(),
+		env.New(test.Namespace, test.AppName),
+	)
+	if err != nil {
+		log.Print(err)
+
+		return
+	}
+
+	port, err := config.Value(ctx, "listen")
+	if err != nil {
+		log.Print("listen: ", err)
+
+		return
+	}
+
+	hostValue, err := config.Value(ctx, "host")
+	if err != nil {
+		log.Print("host:", err)
+
+		return
+	}
+
+	fmt.Printf("listen from env: %d\n", port.Int())
+	fmt.Printf("replace env host by args: %v\n", hostValue.String())
+	// Output:
+	// listen from env: 8080
+	// replace env host by args: gitoa.ru
+}
+
+func ExampleClient_Watch() {
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	_ = os.Setenv("FDEVS_CONFIG_EXAMPLE_ENABLE", "true")
+
+	watcher, err := config.New(
+		watcher.New(time.Microsecond, env.New(test.Namespace, test.AppName)),
+	)
+	if err != nil {
+		log.Print(err)
+
+		return
+	}
+
+	wg := sync.WaitGroup{}
+	wg.Add(1)
+
+	err = watcher.Watch(ctx, func(_ context.Context, oldVar, newVar config.Value) error {
+		fmt.Println("update example_enable old: ", oldVar.Bool(), " new:", newVar.Bool())
+		wg.Done()
+
+		return nil
+	}, "example_enable")
+	if err != nil {
+		log.Print(err)
+
+		return
+	}
+
+	_ = os.Setenv("FDEVS_CONFIG_EXAMPLE_ENABLE", "false")
+
+	err = watcher.Watch(ctx, func(_ context.Context, oldVar, newVar config.Value) error {
+		fmt.Println("update example_db_dsn old: ", oldVar.String(), " new:", newVar.String())
+		wg.Done()
+
+		return nil
+	}, "example_db_dsn")
+	if err != nil {
+		log.Print(err)
+
+		return
+	}
+
+	wg.Wait()
+
+	// Output:
+	// update example_enable old:  true  new: false
+}
+
+func ExampleClient_Value_factory() {
+	ctx := context.Background()
+	_ = os.Setenv("FDEVS_CONFIG_LISTEN", "8080")
+	_ = os.Setenv("FDEVS_CONFIG_HOST", "localhost")
+	_ = os.Setenv("FDEVS_GOLANG_HOST", "go.dev")
+
+	args := os.Args
+
+	defer func() {
+		os.Args = args
+	}()
+
+	os.Args = []string{"main.go", "--env=golang"}
+
+	config, err := config.New(
+		arg.New(),
+		factory.New("factory:env", func(ctx context.Context, cfg config.Provider) (config.Provider, error) {
+			val, err := cfg.Value(ctx, "env")
+			if err != nil {
+				return nil, fmt.Errorf("failed read config file:%w", err)
+			}
+
+			return env.New(test.Namespace, val.String()), nil
+		}),
+		env.New(test.Namespace, test.AppName),
+	)
+	if err != nil {
+		log.Print(err)
+
+		return
+	}
+
+	envName, err := config.Value(ctx, "env")
+	if err != nil {
+		log.Print("env ", err)
+
+		return
+	}
+
+	host, err := config.Value(ctx, "host")
+	if err != nil {
+		log.Print("host ", err)
+
+		return
+	}
+
+	listen, err := config.Value(ctx, "listen")
+	if err != nil {
+		log.Print("listen", err)
+
+		return
+	}
+
+	fmt.Printf("envName from env: %s\n", envName.String())
+	fmt.Printf("host from env with app name golang: %s\n", host.String())
+	fmt.Printf("listen from env with default app name: %s\n", listen.String())
+	// Output:
+	// envName from env: golang
+	// host from env with app name golang: go.dev
+	// listen from env with default app name: 8080
+}

cmd/config/main.go

@@ -0,0 +1,32 @@
+package main
+
+import (
+	"context"
+	"os"
+	"os/signal"
+	"syscall"
+
+	"gitoa.ru/go-4devs/config/definition/generate/command"
+	"gitoa.ru/go-4devs/console"
+)
+
+func main() {
+	ctx, cancel := context.WithCancel(context.Background())
+
+	ch := make(chan os.Signal, 1)
+	defer close(ch)
+
+	signal.Notify(ch, syscall.SIGINT, syscall.SIGTERM)
+
+	go func() {
+		<-ch
+		cancel()
+	}()
+
+	console.
+		New().
+		Add(
+			command.Command(),
+		).
+		Execute(ctx)
+}

compose.yml

@@ -1,7 +1,6 @@
-version: '3'
-
 services:
   vault:
+    container_name: vault
     image: vault:1.13.3
     cap_add:
       - IPC_LOCK
@@ -10,8 +9,11 @@ services:
     environment: 
       VAULT_DEV_ROOT_TOKEN_ID: "dev"
   etcd:
-    image: bitnami/etcd:3.5.11
+    container_name: etcd
+    image: quay.io/coreos/etcd:v3.6.7
     environment: 
       ALLOW_NONE_AUTHENTICATION: "yes"
+      ETCD_LISTEN_CLIENT_URLS: "http://0.0.0.0:2379"
+      ETCD_ADVERTISE_CLIENT_URLS: "http://etcd:2379"
     ports: 
       - "2379:2379"

definition/defenition.go

@@ -0,0 +1,40 @@
+package definition
+
+import (
+	"gitoa.ru/go-4devs/config"
+	"gitoa.ru/go-4devs/config/param"
+)
+
+var _ config.Options = (*Definition)(nil)
+
+func New(opts ...config.Option) *Definition {
+	return &Definition{
+		options: opts,
+		Params:  param.New(),
+	}
+}
+
+type Definition struct {
+	param.Params
+
+	options []config.Option
+}
+
+func (d *Definition) Add(opts ...config.Option) {
+	d.options = append(d.options, opts...)
+}
+
+func (d *Definition) Options() []config.Option {
+	return d.options
+}
+
+func (d *Definition) With(params param.Params) *Definition {
+	def := &Definition{
+		options: make([]config.Option, len(d.options)),
+		Params:  param.Chain(params, d.Params),
+	}
+
+	copy(def.options, d.options)
+
+	return def
+}

definition/generate/bootstrap/bootstrap.go

@@ -0,0 +1,94 @@
+package bootstrap
+
+import (
+	"context"
+	"embed"
+	"fmt"
+	"os"
+	"path/filepath"
+	"text/template"
+
+	"gitoa.ru/go-4devs/config/definition/generate/pkg"
+)
+
+//go:embed *.tpl
+var tpls embed.FS
+
+type Boot struct {
+	Config
+	*pkg.Packages
+
+	Configure []string
+}
+
+func (b Boot) Pkg() string {
+	return pkg.Pkg(b.FullPkg())
+}
+
+type Config interface {
+	File() string
+	Methods() []string
+	SkipContext() bool
+	Prefix() string
+	Suffix() string
+	FullPkg() string
+}
+
+func Bootstrap(ctx context.Context, cfg Config) (string, error) {
+	fInfo, err := os.Stat(cfg.File())
+	if err != nil {
+		return "", fmt.Errorf("stat[%v]:%w", cfg.File(), err)
+	}
+
+	pkgPath, err := pkg.ByPath(ctx, cfg.File(), fInfo.IsDir())
+	if err != nil {
+		return "", fmt.Errorf("pkg by path:%w", err)
+	}
+
+	tmpFile, err := os.CreateTemp(filepath.Dir(fInfo.Name()), "config-bootstrap")
+	if err != nil {
+		return "", fmt.Errorf("create tmp file:%w", err)
+	}
+
+	tpl, err := template.ParseFS(tpls, "bootstrap.go.tpl")
+	if err != nil {
+		return "", fmt.Errorf("parse template:%w", err)
+	}
+
+	imports := pkg.NewImports("main").
+		Adds(
+			"context",
+			"gitoa.ru/go-4devs/config/definition",
+			"gitoa.ru/go-4devs/config",
+			"gitoa.ru/go-4devs/config/definition/generate/view",
+			"gitoa.ru/go-4devs/config/param",
+			"gitoa.ru/go-4devs/config/definition/generate",
+			"os",
+			"io",
+			"fmt",
+			pkgPath,
+		)
+
+	data := Boot{
+		Packages:  imports,
+		Configure: cfg.Methods(),
+		Config:    cfg,
+	}
+
+	if err := tpl.Execute(tmpFile, data); err != nil {
+		return "", fmt.Errorf("execute:%w", err)
+	}
+
+	src := tmpFile.Name()
+	if err := tmpFile.Close(); err != nil {
+		return src, fmt.Errorf("close file:%w", err)
+	}
+
+	dest := src + ".go"
+
+	if err := os.Rename(src, dest); err != nil {
+		return dest, fmt.Errorf("rename idt:%w", err)
+	}
+
+	return dest, nil
+}

definition/generate/bootstrap/bootstrap.go.tpl

@@ -0,0 +1,43 @@
+//go:build ignore
+// +build ignore
+
+package main
+
+import (
+	{{range .Imports}}
+    {{- .Alias }}"{{ .Package }}"
+    {{end}}
+)
+
+func main() {
+	if err := run(os.Stdout); err != nil {
+		fmt.Fprintln(os.Stderr, err)
+		os.Exit(1)
+	}
+}
+
+func run(f io.Writer) error {
+	ctx := context.Background()
+
+	defs:=make([]config.Options,0)
+{{ range .Configure }} 
+	params{{.}} := param.New(
+	{{- if $.SkipContext }}view.WithSkipContext,{{ end }}
+	view.WithStructName("{{$.Prefix}}_{{.}}_{{$.Suffix}}"),
+	view.WithStructPrefix("{{$.Prefix}}"),
+  view.WithStructSuffix("{{$.Suffix}}"),
+	)
+
+	def{{.}} := definition.New().With(params{{.}})
+	if err := {{$.Pkg}}.{{.}}(ctx, def{{.}}); err != nil {
+		return err
+	}
+	defs = append(defs,def{{.}})
+{{ end }}
+
+	if gerr := generate.Run(ctx,"{{.FullPkg}}",f, defs...);gerr != nil {
+		return gerr
+	}
+
+  return nil
+}

definition/generate/command/generate.go

@@ -0,0 +1,68 @@
+package command
+
+import (
+	"context"
+	"fmt"
+	"os"
+
+	"gitoa.ru/go-4devs/config"
+	"gitoa.ru/go-4devs/config/definition/generate"
+	"gitoa.ru/go-4devs/config/provider/chain"
+	"gitoa.ru/go-4devs/console"
+	"gitoa.ru/go-4devs/console/output"
+)
+
+const Name = "config:generate"
+
+func Handle(ctx context.Context, in config.Provider, out output.Output, next console.Action) error {
+	var name string
+
+	value, err := in.Value(ctx, generate.OptionFile)
+	if err == nil {
+		name = value.String()
+	}
+
+	if name == "" {
+		name = os.Getenv("GOFILE")
+	}
+
+	parser, err := generate.Parse(ctx, name)
+	if err != nil {
+		return fmt.Errorf("parse:%w", err)
+	}
+
+	mem, merr := generate.NewMemoryProvider(name,
+		generate.WithOutName(parser.OutName()),
+		generate.WithFullPkg(parser.FullPkg()),
+		generate.WithMethods(parser.Methods()...),
+	)
+	if merr != nil {
+		return fmt.Errorf("mem provider:%w", merr)
+	}
+
+	return next(ctx, chain.New(in, mem), out)
+}
+
+func Execute(ctx context.Context, in config.Provider, _ output.Output) error {
+	cfg := generate.NewConfigure(ctx, in)
+
+	if err := generate.Generate(ctx, cfg); err != nil {
+		return fmt.Errorf("%w", err)
+	}
+
+	return nil
+}
+
+func Command() *console.Command {
+	return &console.Command{
+		Description: "",
+		Help:        "",
+		Version:     "v0.0.1",
+		Hidden:      false,
+		Prepare:     nil,
+		Handle:      Handle,
+		Name:        Name,
+		Execute:     Execute,
+		Configure:   generate.Configure,
+	}
+}

definition/generate/configure.go

@@ -0,0 +1,134 @@
+package generate
+
+import (
+	"context"
+	"fmt"
+	"strconv"
+
+	"gitoa.ru/go-4devs/config"
+	"gitoa.ru/go-4devs/config/definition/option"
+	"gitoa.ru/go-4devs/config/provider/memory"
+)
+
+const (
+	OptionFile        = "file"
+	optionPrefix      = "prefix"
+	optionSuffix      = "suffix"
+	optionSkipContext = "skip-context"
+	optionBuildTags   = "build-tags"
+	optionOutName     = "out-name"
+	optionMethod      = "method"
+	optionFullPkg     = "full-pkg"
+)
+
+func WithPrefix(in string) func(*memory.Map) error {
+	return func(m *memory.Map) error {
+		err := m.AppendOption(in, optionPrefix)
+		if err != nil {
+			return fmt.Errorf("append %v:%w", optionPrefix, err)
+		}
+
+		return nil
+	}
+}
+
+func WithSuffix(in string) func(*memory.Map) error {
+	return func(m *memory.Map) error {
+		err := m.AppendOption(in, optionSuffix)
+		if err != nil {
+			return fmt.Errorf("append %v:%w", optionSuffix, err)
+		}
+
+		return nil
+	}
+}
+
+func WithSkipContext(in bool) func(*memory.Map) error {
+	return func(m *memory.Map) error {
+		err := m.AppendOption(strconv.FormatBool(in), optionSkipContext)
+		if err != nil {
+			return fmt.Errorf("append %v:%w", optionSkipContext, err)
+		}
+
+		return nil
+	}
+}
+
+func WithBuildTags(in string) func(*memory.Map) error {
+	return func(m *memory.Map) error {
+		err := m.AppendOption(in, optionBuildTags)
+		if err != nil {
+			return fmt.Errorf("append %v:%w", optionBuildTags, err)
+		}
+
+		return nil
+	}
+}
+
+func WithOutName(in string) func(*memory.Map) error {
+	return func(m *memory.Map) error {
+		err := m.AppendOption(in, optionOutName)
+		if err != nil {
+			return fmt.Errorf("append %v:%w", optionOutName, err)
+		}
+
+		return nil
+	}
+}
+
+func WithMethods(methods ...string) func(*memory.Map) error {
+	return func(m *memory.Map) error {
+		for _, method := range methods {
+			err := m.AppendOption(method, optionMethod)
+			if err != nil {
+				return fmt.Errorf("append %v:%w", optionMethod, err)
+			}
+		}
+
+		return nil
+	}
+}
+
+func WithFullPkg(in string) func(*memory.Map) error {
+	return func(m *memory.Map) error {
+		err := m.AppendOption(in, optionFullPkg)
+		if err != nil {
+			return fmt.Errorf("append %v:%w", optionFullPkg, err)
+		}
+
+		return nil
+	}
+}
+
+func NewMemoryProvider(file string, opts ...func(*memory.Map) error) (*memory.Map, error) {
+	cfg := new(memory.Map)
+
+	err := cfg.AppendOption(file, OptionFile)
+	if err != nil {
+		return nil, fmt.Errorf("append %v:%w", OptionFile, err)
+	}
+
+	for idx, opt := range opts {
+		err = opt(cfg)
+		if err != nil {
+			return nil, fmt.Errorf("opt[%d]:%w", idx, err)
+		}
+	}
+
+	return cfg, nil
+}
+
+func Configure(_ context.Context, def config.Definition) error {
+	def.Add(
+		option.String(OptionFile, "set file", option.Required),
+		option.String(optionPrefix, "struct prefix"),
+		option.String(optionSuffix, "struct suffix", option.Default("Config")),
+		option.Bool(optionSkipContext, "skip contect to method"),
+		option.String(optionBuildTags, "add build tags"),
+		option.String(optionOutName, "set out name"),
+		option.String(optionMethod, "set method", option.Slice),
+		option.String(optionFullPkg, "set full pkg"),
+	)
+
+	return nil
+}

definition/generate/configure_config.go

@@ -0,0 +1,231 @@
+package generate
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"log"
+
+	"gitoa.ru/go-4devs/config"
+)
+
+func NewConfigure(ctx context.Context, prov config.Provider) ConfigureConfig {
+	return ConfigureConfig{
+		Provider: prov,
+		ctx:      ctx,
+		handle: func(err error) {
+			if !errors.Is(err, config.ErrNotFound) {
+				log.Print(err)
+			}
+		},
+	}
+}
+
+type ConfigureConfig struct {
+	config.Provider
+
+	ctx    context.Context //nolint:containedctx
+	handle func(err error)
+}
+
+func (i ConfigureConfig) ReadBuildTags() (string, error) {
+	val, verr := i.Value(i.ctx, optionBuildTags)
+	if verr != nil {
+		return "", fmt.Errorf("get %v:%w", optionBuildTags, verr)
+	}
+
+	data, err := val.ParseString()
+	if err != nil {
+		return "", fmt.Errorf("parse %v:%w", optionBuildTags, err)
+	}
+
+	return data, nil
+}
+
+func (i ConfigureConfig) BuildTags() string {
+	data, err := i.ReadBuildTags()
+	if err != nil {
+		i.handle(err)
+
+		return ""
+	}
+
+	return data
+}
+
+func (i ConfigureConfig) ReadOutName() (string, error) {
+	val, err := i.Value(i.ctx, optionOutName)
+	if err != nil {
+		return "", fmt.Errorf("get %v:%w", optionOutName, err)
+	}
+
+	data, derr := val.ParseString()
+	if derr != nil {
+		return "", fmt.Errorf("parse %v:%w", optionOutName, derr)
+	}
+
+	return data, nil
+}
+
+func (i ConfigureConfig) OutName() string {
+	data, err := i.ReadOutName()
+	if err != nil {
+		i.handle(err)
+
+		return ""
+	}
+
+	return data
+}
+
+func (i ConfigureConfig) ReadFile() (string, error) {
+	val, err := i.Value(i.ctx, OptionFile)
+	if err != nil {
+		return "", fmt.Errorf("get %v:%w", OptionFile, err)
+	}
+
+	data, derr := val.ParseString()
+	if derr != nil {
+		return "", fmt.Errorf("parse %v:%w", OptionFile, derr)
+	}
+
+	return data, nil
+}
+
+func (i ConfigureConfig) File() string {
+	data, err := i.ReadFile()
+	if err != nil {
+		i.handle(err)
+
+		return ""
+	}
+
+	return data
+}
+
+func (i ConfigureConfig) ReadMethods() ([]string, error) {
+	val, err := i.Value(i.ctx, optionMethod)
+	if err != nil {
+		return nil, fmt.Errorf("get %v:%w", optionMethod, err)
+	}
+
+	var data []string
+
+	perr := val.Unmarshal(&data)
+	if perr != nil {
+		return nil, fmt.Errorf("unmarshal %v:%w", optionMethod, perr)
+	}
+
+	return data, nil
+}
+
+func (i ConfigureConfig) Methods() []string {
+	data, err := i.ReadMethods()
+	if err != nil {
+		i.handle(err)
+
+		return nil
+	}
+
+	return data
+}
+
+func (i ConfigureConfig) ReadSkipContext() (bool, error) {
+	val, err := i.Value(i.ctx, optionSkipContext)
+	if err != nil {
+		return false, fmt.Errorf("get %v:%w", optionSkipContext, err)
+	}
+
+	data, derr := val.ParseBool()
+	if derr != nil {
+		return false, fmt.Errorf("parse %v:%w", optionSkipContext, derr)
+	}
+
+	return data, nil
+}
+
+func (i ConfigureConfig) SkipContext() bool {
+	data, err := i.ReadSkipContext()
+	if err != nil {
+		i.handle(err)
+
+		return false
+	}
+
+	return data
+}
+
+func (i ConfigureConfig) ReadPrefix() (string, error) {
+	val, err := i.Value(i.ctx, optionPrefix)
+	if err != nil {
+		return "", fmt.Errorf("get %v: %w", optionPrefix, err)
+	}
+
+	data, derr := val.ParseString()
+	if derr != nil {
+		return "", fmt.Errorf("parse %v:%w", optionPrefix, derr)
+	}
+
+	return data, nil
+}
+
+func (i ConfigureConfig) Prefix() string {
+	val, err := i.ReadPrefix()
+	if err != nil {
+		i.handle(err)
+
+		return ""
+	}
+
+	return val
+}
+
+func (i ConfigureConfig) ReadSuffix() (string, error) {
+	val, err := i.Value(i.ctx, optionSuffix)
+	if err != nil {
+		return "", fmt.Errorf("get %v:%w", optionSuffix, err)
+	}
+
+	data, derr := val.ParseString()
+	if derr != nil {
+		return "", fmt.Errorf("parse %v:%w", optionSuffix, derr)
+	}
+
+	return data, nil
+}
+
+func (i ConfigureConfig) Suffix() string {
+	data, err := i.ReadSuffix()
+	if err != nil {
+		i.handle(err)
+
+		return ""
+	}
+
+	return data
+}
+
+func (i ConfigureConfig) ReadFullPkg() (string, error) {
+	val, err := i.Value(i.ctx, optionFullPkg)
+	if err != nil {
+		return "", fmt.Errorf("get %v:%w", optionFullPkg, err)
+	}
+
+	data, derr := val.ParseString()
+	if derr != nil {
+		return "", fmt.Errorf("parse %v:%w", optionFullPkg, derr)
+	}
+
+	return data, nil
+}
+
+func (i ConfigureConfig) FullPkg() string {
+	data, err := i.ReadFullPkg()
+	if err != nil {
+		i.handle(err)
+
+		return ""
+	}
+
+	return data
+}

definition/generate/example/example.go

@@ -0,0 +1,39 @@
+package example
+
+import (
+	"context"
+
+	configs "gitoa.ru/go-4devs/config"
+	"gitoa.ru/go-4devs/config/definition/generate/view"
+	"gitoa.ru/go-4devs/config/definition/group"
+	"gitoa.ru/go-4devs/config/definition/option"
+	"gitoa.ru/go-4devs/config/definition/proto"
+)
+
+//go:generate go run ../../../cmd/config/main.go config:generate
+
+type Level string
+
+func (l *Level) UnmarshalText(in []byte) error {
+	data := string(in)
+	*l = Level(data)
+
+	return nil
+}
+
+func Example(_ context.Context, def configs.Definition) error {
+	def.Add(
+		option.String("test", "test string", view.WithSkipContext),
+		group.New("user", "configure user",
+			option.String("name", "name", option.Default("4devs")),
+			option.String("pass", "password"),
+		).With(view.WithContext),
+
+		group.New("log", "configure logger",
+			option.New("level", "log level", Level("")),
+			proto.New("service", "servise logger", option.New("level", "log level", Level(""))),
+		),
+	)
+
+	return nil
+}

definition/generate/example/example_config.go

@@ -0,0 +1,153 @@
+// Code generated gitoa.ru/go-4devs/config DO NOT EDIT.
+package example
+
+import (
+	"context"
+	"fmt"
+	"gitoa.ru/go-4devs/config"
+)
+
+func WithExampleConfigHandle(fn func(context.Context, error)) func(*ExampleConfig) {
+	return func(ci *ExampleConfig) {
+		ci.handle = fn
+	}
+}
+
+func NewExampleConfig(ctx context.Context, prov config.Provider, opts ...func(*ExampleConfig)) ExampleConfig {
+	i := ExampleConfig{
+		Provider: prov,
+		handle: func(_ context.Context, err error) {
+			fmt.Printf("ExampleConfig:%v", err)
+		},
+		ctx: ctx,
+	}
+
+	for _, opt := range opts {
+		opt(&i)
+	}
+
+	return i
+}
+
+type ExampleConfig struct {
+	config.Provider
+	handle func(context.Context, error)
+	ctx    context.Context
+}
+
+// readTest test string.
+func (i ExampleConfig) readTest(ctx context.Context) (v string, e error) {
+	val, err := i.Value(ctx, "test")
+	if err != nil {
+		return v, fmt.Errorf("read [%v]:%w", []string{"test"}, err)
+
+	}
+
+	return val.ParseString()
+
+}
+
+// ReadTest test string.
+func (i ExampleConfig) ReadTest() (string, error) {
+	return i.readTest(i.ctx)
+}
+
+// Test test string.
+func (i ExampleConfig) Test() string {
+	val, err := i.readTest(i.ctx)
+	if err != nil {
+		i.handle(i.ctx, err)
+	}
+
+	return val
+}
+
+type UserConfig struct {
+	ExampleConfig
+}
+
+// User configure user.
+func (i ExampleConfig) User() UserConfig {
+	return UserConfig{i}
+}
+
+type LogConfig struct {
+	ExampleConfig
+}
+
+// Log configure logger.
+func (i ExampleConfig) Log() LogConfig {
+	return LogConfig{i}
+}
+
+// readLevel log level.
+func (i LogConfig) readLevel(ctx context.Context) (v Level, e error) {
+	val, err := i.Value(ctx, "log", "level")
+	if err != nil {
+		return v, fmt.Errorf("read [%v]:%w", []string{"log", "level"}, err)
+
+	}
+
+	pval, perr := val.ParseString()
+	if perr != nil {
+		return v, fmt.Errorf("parse [%v]:%w", []string{"log", "level"}, perr)
+	}
+
+	return v, v.UnmarshalText([]byte(pval))
+}
+
+// ReadLevel log level.
+func (i LogConfig) ReadLevel(ctx context.Context) (Level, error) {
+	return i.readLevel(ctx)
+}
+
+// Level log level.
+func (i LogConfig) Level(ctx context.Context) Level {
+	val, err := i.readLevel(ctx)
+	if err != nil {
+		i.handle(ctx, err)
+	}
+
+	return val
+}
+
+type LogServiceConfig struct {
+	LogConfig
+	service string
+}
+
+// Service servise logger.
+func (i LogConfig) Service(key string) LogServiceConfig {
+	return LogServiceConfig{i, key}
+}
+
+// readLevel log level.
+func (i LogServiceConfig) readLevel(ctx context.Context) (v Level, e error) {
+	val, err := i.Value(ctx, "log", i.service, "level")
+	if err != nil {
+		return v, fmt.Errorf("read [%v]:%w", []string{"log", i.service, "level"}, err)
+
+	}
+
+	pval, perr := val.ParseString()
+	if perr != nil {
+		return v, fmt.Errorf("parse [%v]:%w", []string{"log", i.service, "level"}, perr)
+	}
+
+	return v, v.UnmarshalText([]byte(pval))
+}
+
+// ReadLevel log level.
+func (i LogServiceConfig) ReadLevel(ctx context.Context) (Level, error) {
+	return i.readLevel(ctx)
+}
+
+// Level log level.
+func (i LogServiceConfig) Level(ctx context.Context) Level {
+	val, err := i.readLevel(ctx)
+	if err != nil {
+		i.handle(ctx, err)
+	}
+
+	return val
+}

definition/generate/exec.go

@@ -0,0 +1,70 @@
+package generate
+
+import (
+	"context"
+	"fmt"
+	"go/format"
+	"os"
+	"os/exec"
+	"path/filepath"
+
+	"gitoa.ru/go-4devs/config/definition/generate/bootstrap"
+)
+
+type GConfig interface {
+	BuildTags() string
+	OutName() string
+	bootstrap.Config
+}
+
+func Generate(ctx context.Context, cfg GConfig) error {
+	path, err := bootstrap.Bootstrap(ctx, cfg)
+	defer os.Remove(path)
+
+	if err != nil {
+		return fmt.Errorf("build bootstrap:%w", err)
+	}
+
+	tmpFile, err := os.Create(cfg.File() + ".tmp")
+	if err != nil {
+		return fmt.Errorf("create tmp file:%w", err)
+	}
+
+	defer os.Remove(tmpFile.Name()) // will not remove after rename
+
+	execArgs := []string{"run"}
+	if len(cfg.BuildTags()) > 0 {
+		execArgs = append(execArgs, "-tags", cfg.BuildTags())
+	}
+
+	execArgs = append(execArgs, filepath.Base(path))
+	cmd := exec.CommandContext(ctx, "go", execArgs...)
+
+	cmd.Stdout = tmpFile
+	cmd.Stderr = os.Stderr
+
+	cmd.Dir = filepath.Dir(path)
+	if err = cmd.Run(); err != nil {
+		return fmt.Errorf("start cmd:%w", err)
+	}
+
+	tmpFile.Close()
+
+	// format file and write to out path
+	in, err := os.ReadFile(tmpFile.Name())
+	if err != nil {
+		return fmt.Errorf("read file: %w", err)
+	}
+
+	out, err := format.Source(in)
+	if err != nil {
+		return fmt.Errorf("format source:%w", err)
+	}
+
+	err = os.WriteFile(cfg.OutName(), out, 0o644) //nolint:gosec,mnd
+	if err != nil {
+		return fmt.Errorf("write file:%w", err)
+	}
+
+	return nil
+}

definition/generate/generate.go

@@ -0,0 +1,84 @@
+package generate
+
+import (
+	"bytes"
+	"context"
+	"embed"
+	"fmt"
+	"io"
+	"strings"
+	"text/template"
+	"unicode"
+
+	"gitoa.ru/go-4devs/config"
+	"gitoa.ru/go-4devs/config/definition/generate/pkg"
+	"gitoa.ru/go-4devs/config/definition/generate/render"
+	"gitoa.ru/go-4devs/config/definition/generate/view"
+)
+
+//go:embed tpl/*
+var tpls embed.FS
+
+var initTpl = template.Must(template.New("tpls").ParseFS(tpls, "tpl/*.tpl")).Lookup("init.go.tpl")
+
+func Run(_ context.Context, fullPkg string, w io.Writer, defs ...config.Options) error {
+	data := Data{
+		Packages: pkg.NewImports(fullPkg).
+			Adds("fmt", "context", "gitoa.ru/go-4devs/config"),
+	}
+
+	var buff bytes.Buffer
+
+	for _, in := range defs {
+		vi := view.NewViews(in)
+
+		if err := render.Render(&buff, vi, data); err != nil {
+			return fmt.Errorf("render:%w", err)
+		}
+	}
+
+	if err := initTpl.Execute(w, data); err != nil {
+		return fmt.Errorf("render base:%w", err)
+	}
+
+	if _, err := io.Copy(w, &buff); err != nil {
+		return fmt.Errorf("copy:%w", err)
+	}
+
+	return nil
+}
+
+type Data struct {
+	*pkg.Packages
+}
+
+func (f Data) StructName(name string) string {
+	return FuncName(name)
+}
+
+func (f Data) FuncName(in string) string {
+	return FuncName(in)
+}
+
+func FuncName(name string) string {
+	data := strings.Builder{}
+	toUp := true
+
+	for _, char := range name {
+		isLeter := unicode.IsLetter(char)
+		isAllowed := isLeter || unicode.IsDigit(char)
+
+		switch {
+		case isAllowed && !toUp:
+			data.WriteRune(char)
+		case !isAllowed:
+			toUp = true
+		case toUp:
+			data.WriteString(strings.ToUpper(string(char)))
+
+			toUp = false
+		}
+	}
+
+	return data.String()
+}

definition/generate/generate_test.go

@@ -0,0 +1,88 @@
+package generate_test
+
+import (
+	"context"
+	"os"
+	"testing"
+
+	"gitoa.ru/go-4devs/config/definition"
+	"gitoa.ru/go-4devs/config/definition/generate"
+	"gitoa.ru/go-4devs/config/definition/generate/bootstrap"
+	"gitoa.ru/go-4devs/config/definition/generate/view"
+	"gitoa.ru/go-4devs/config/definition/group"
+	"gitoa.ru/go-4devs/config/definition/option"
+	"gitoa.ru/go-4devs/config/definition/proto"
+	"gitoa.ru/go-4devs/config/test/require"
+)
+
+type LogLevel string
+
+func (l *LogLevel) UnmarshalText(in []byte) error {
+	data := string(in)
+	*l = LogLevel(data)
+
+	return nil
+}
+
+func Configure(_ context.Context, def *definition.Definition) error {
+	def.Add(
+		option.String("test", "test string", view.WithSkipContext),
+		group.New("user", "configure user",
+			option.String("name", "name", option.Default("4devs")),
+			option.String("pass", "password"),
+		),
+
+		group.New("log", "configure logger",
+			option.New("level", "log level", LogLevel("")),
+			proto.New("service", "servise logger", option.New("level", "log level", LogLevel(""))),
+		),
+	)
+
+	return nil
+}
+
+func TestGenerate_Bootstrap(t *testing.T) {
+	t.SkipNow()
+	t.Parallel()
+
+	ctx := context.Background()
+	options := definition.New()
+	err := Configure(ctx, options)
+	require.NoError(t, err)
+
+	cfg, _ := generate.NewMemoryProvider("generate_test.go",
+		generate.WithMethods("Config"),
+		generate.WithFullPkg("gitoa.ru/go-4devs/config/definition/generate_test"),
+	)
+
+	path, err := bootstrap.Bootstrap(ctx, generate.NewConfigure(ctx, cfg))
+	if err != nil {
+		t.Error(err)
+		t.FailNow()
+	}
+
+	os.Remove(path)
+
+	t.Log(path)
+	t.FailNow()
+}
+
+func TestGenerate_Genereate(t *testing.T) {
+	t.SkipNow()
+	t.Parallel()
+
+	ctx := context.Background()
+	options := definition.New()
+	err := Configure(ctx, options)
+	require.NoError(t, err)
+
+	cfg, _ := generate.NewMemoryProvider("generate_test.go",
+		generate.WithMethods("Config"),
+		generate.WithFullPkg("gitoa.ru/go-4devs/config/definition/generate_test"),
+	)
+
+	err = generate.Generate(ctx, generate.NewConfigure(ctx, cfg))
+	require.NoError(t, err)
+
+	t.FailNow()
+}

definition/generate/parser.go

@@ -0,0 +1,152 @@
+package generate
+
+import (
+	"context"
+	"fmt"
+	"go/ast"
+	"go/parser"
+	"go/token"
+	"os"
+	"reflect"
+	"slices"
+	"strings"
+
+	"gitoa.ru/go-4devs/config"
+	"gitoa.ru/go-4devs/config/definition/generate/pkg"
+)
+
+const NameSuffix = "_config.go"
+
+func Parse(ctx context.Context, name string) (Parser, error) {
+	var parse Parser
+
+	parse.file = name
+
+	stats, err := os.Stat(name)
+	if err != nil {
+		return parse, fmt.Errorf("stats:%w", err)
+	}
+
+	parse.fullPkg, err = pkg.ByPath(ctx, name, stats.IsDir())
+	if err != nil {
+		return parse, fmt.Errorf("get pkg:%w", err)
+	}
+
+	parse.methods, err = NewParseMethods(
+		name,
+		[]reflect.Type{
+			reflect.TypeFor[context.Context](),
+			reflect.TypeFor[config.Definition](),
+		},
+		[]reflect.Type{reflect.TypeFor[error]()},
+	)
+	if err != nil {
+		return parse, fmt.Errorf("parse methods:%w", err)
+	}
+
+	return parse, nil
+}
+
+func NewParseMethods(file string, params []reflect.Type, results []reflect.Type) ([]string, error) {
+	pfile, err := parser.ParseFile(token.NewFileSet(), file, nil, parser.ParseComments)
+	if err != nil {
+		return nil, fmt.Errorf("parse:%w", err)
+	}
+
+	resultAlias := importAlias(pfile, results)
+	paramsAlias := importAlias(pfile, params)
+
+	var methods []string
+
+	ast.Inspect(pfile, func(anode ast.Node) bool {
+		if fn, ok := anode.(*ast.FuncDecl); ok &&
+			fn.Recv == nil &&
+			fn.Type != nil &&
+			(fn.Type.Params != nil && len(params) == len(fn.Type.Params.List) || len(params) == 0 && fn.Type.Params == nil) &&
+			(fn.Type.Results != nil && len(results) == len(fn.Type.Results.List) || len(results) == 0 && fn.Type.Results == nil) {
+			if hasFields(fn.Type.Params, params, paramsAlias) && hasFields(fn.Type.Results, results, resultAlias) {
+				methods = append(methods, fn.Name.String())
+			}
+		}
+
+		return true
+	})
+
+	return methods, nil
+}
+
+func importAlias(file *ast.File, params []reflect.Type) map[int][]string {
+	paramsAlias := make(map[int][]string, len(params))
+	for idx := range params {
+		name := params[idx].Name()
+		if pkgPath := params[idx].PkgPath(); pkgPath != "" {
+			name = pkg.Pkg(pkgPath)
+		}
+
+		paramsAlias[idx] = append(paramsAlias[idx], name)
+	}
+
+	ast.Inspect(file, func(anode ast.Node) bool {
+		if exp, ok := anode.(*ast.ImportSpec); ok {
+			pathName := strings.Trim(exp.Path.Value, "\"")
+			pname := pkg.Pkg(pathName)
+
+			if exp.Name != nil {
+				pname = exp.Name.String()
+			}
+
+			for idx, param := range params {
+				if pathName == param.PkgPath() {
+					paramsAlias[idx] = append(paramsAlias[idx], pname)
+				}
+			}
+		}
+
+		return true
+	})
+
+	return paramsAlias
+}
+
+func hasFields(fields *ast.FieldList, params []reflect.Type, alias map[int][]string) bool {
+	for idx, one := range fields.List {
+		iparam := params[idx]
+		if ident, iok := one.Type.(*ast.Ident); iok && iparam.String() == ident.String() {
+			return true
+		}
+
+		selector, sok := one.Type.(*ast.SelectorExpr)
+		if !sok {
+			return false
+		}
+
+		if iparam.Name() != selector.Sel.String() {
+			return false
+		}
+
+		salias, saok := selector.X.(*ast.Ident)
+		if iparam.PkgPath() != "" && saok && !slices.Contains(alias[idx], salias.String()) {
+			return false
+		}
+	}
+
+	return true
+}
+
+type Parser struct {
+	file    string
+	fullPkg string
+	methods []string
+}
+
+func (p Parser) OutName() string {
+	return strings.ReplaceAll(p.file, ".go", NameSuffix)
+}
+
+func (p Parser) FullPkg() string {
+	return p.fullPkg
+}
+
+func (p Parser) Methods() []string {
+	return p.methods
+}

definition/generate/pkg/alias.go

@@ -0,0 +1,29 @@
+package pkg
+
+import (
+	"strings"
+	"unicode"
+)
+
+func AliasName(name string) string {
+	data := strings.Builder{}
+	toUp := false
+
+	for _, char := range name {
+		isLeter := unicode.IsLetter(char)
+		isAllowed := isLeter || unicode.IsDigit(char)
+
+		switch {
+		case isAllowed && !toUp:
+			data.WriteRune(char)
+		case !isAllowed && data.Len() > 0:
+			toUp = true
+		case toUp:
+			data.WriteString(strings.ToUpper(string(char)))
+
+			toUp = false
+		}
+	}
+
+	return data.String()
+}

definition/generate/pkg/errors.go

@@ -0,0 +1,8 @@
+package pkg
+
+import "errors"
+
+var (
+	ErrWrongFormat = errors.New("wrong format")
+	ErrNotFound    = errors.New("not found")
+)

definition/generate/pkg/imports.go

@@ -0,0 +1,130 @@
+package pkg
+
+import (
+	"fmt"
+	"strconv"
+	"strings"
+)
+
+func NewImports(pkg string) *Packages {
+	imp := Packages{
+		data: make(map[string]string),
+		pkg:  pkg,
+	}
+
+	return &imp
+}
+
+type Packages struct {
+	data map[string]string
+	pkg  string
+}
+
+func (i *Packages) Imports() []Import {
+	imports := make([]Import, 0, len(i.data))
+	for name, alias := range i.data {
+		imports = append(imports, Import{
+			Package: name,
+			Alias:   alias,
+		})
+	}
+
+	return imports
+}
+
+func (i *Packages) Short(fullType string) (string, error) {
+	idx := strings.LastIndexByte(fullType, '.')
+	if idx == -1 {
+		return "", fmt.Errorf("%w: expect package.Type", ErrWrongFormat)
+	}
+
+	if alias, ok := i.data[fullType[:idx]]; ok {
+		return alias + fullType[idx:], nil
+	}
+
+	return "", fmt.Errorf("%w alias for pkg %v", ErrNotFound, fullType[:idx])
+}
+
+func (i *Packages) AddType(fullType string) (string, error) {
+	idx := strings.LastIndexByte(fullType, '.')
+	if idx == -1 {
+		return "", fmt.Errorf("%w: expect pckage.Type got %v", ErrWrongFormat, fullType)
+	}
+
+	imp := i.Add(fullType[:idx])
+
+	if imp.Alias == "" {
+		return fullType[idx+1:], nil
+	}
+
+	return imp.Alias + fullType[idx:], nil
+}
+
+func (i *Packages) Adds(pkgs ...string) *Packages {
+	for _, pkg := range pkgs {
+		i.Add(pkg)
+	}
+
+	return i
+}
+
+func (i *Packages) Add(pkg string) Import {
+	if pkg == i.pkg {
+		return Import{
+			Alias:   "",
+			Package: pkg,
+		}
+	}
+
+	alias := pkg
+
+	if idx := strings.LastIndexByte(pkg, '/'); idx != -1 {
+		alias = AliasName(pkg[idx+1:])
+	}
+
+	if al, ok := i.data[pkg]; ok {
+		return Import{Package: pkg, Alias: al}
+	}
+
+	for _, al := range i.data {
+		if al == alias {
+			alias += strconv.Itoa(len(i.data))
+		}
+	}
+
+	i.data[pkg] = alias
+
+	return Import{
+		Alias:   alias,
+		Package: pkg,
+	}
+}
+
+func (i *Packages) Pkg() string {
+	return Pkg(i.pkg)
+}
+
+type Import struct {
+	Alias   string
+	Package string
+}
+
+func (i Import) Pkg() string {
+	return Pkg(i.Package)
+}
+
+func (i Import) String() string {
+	if i.Alias == i.Pkg() {
+		return fmt.Sprintf("%q", i.Package)
+	}
+
+	return fmt.Sprintf("%s %q", i.Alias, i.Package)
+}
+
+func Pkg(fullPkg string) string {
+	if idx := strings.LastIndex(fullPkg, "/"); idx != -1 {
+		return fullPkg[idx+1:]
+	}
+
+	return fullPkg
+}

definition/generate/pkg/pkg.go

@@ -0,0 +1,187 @@
+package pkg
+
+import (
+	"bytes"
+	"context"
+	"fmt"
+	"go/build"
+	"os"
+	"os/exec"
+	"path"
+	"path/filepath"
+	"strconv"
+	"strings"
+	"sync"
+)
+
+var cache = sync.Map{}
+
+func ByPath(ctx context.Context, fname string, isDir bool) (string, error) {
+	if !filepath.IsAbs(fname) {
+		pwd, err := os.Getwd()
+		if err != nil {
+			return "", fmt.Errorf("%w", err)
+		}
+
+		fname = filepath.Join(pwd, fname)
+	}
+
+	goModPath, _ := goModPath(ctx, fname, isDir)
+	if strings.Contains(goModPath, "go.mod") {
+		pkgPath, err := getPkgPathFromGoMod(fname, isDir, goModPath)
+		if err != nil {
+			return "", err
+		}
+
+		return pkgPath, nil
+	}
+
+	return getPkgPathFromGOPATH(fname, isDir)
+}
+
+// empty if no go.mod, GO111MODULE=off or go without go modules support.
+func goModPath(ctx context.Context, fname string, isDir bool) (string, error) {
+	root := fname
+	if !isDir {
+		root = filepath.Dir(fname)
+	}
+
+	var modPath string
+
+	loadModPath, ok := cache.Load(root)
+	if ok {
+		modPath, _ = loadModPath.(string)
+
+		return modPath, nil
+	}
+
+	defer func() {
+		cache.Store(root, modPath)
+	}()
+
+	cmd := exec.CommandContext(ctx, "go", "env", "GOMOD")
+	cmd.Dir = root
+
+	stdout, err := cmd.Output()
+	if err != nil {
+		return "", fmt.Errorf("%w", err)
+	}
+
+	modPath = string(bytes.TrimSpace(stdout))
+
+	return modPath, nil
+}
+
+func getPkgPathFromGoMod(fname string, isDir bool, goModPath string) (string, error) {
+	modulePath := getModulePath(goModPath)
+	if modulePath == "" {
+		return "", fmt.Errorf("c%w module path from %s", ErrNotFound, goModPath)
+	}
+
+	rel := path.Join(modulePath, filePathToPackagePath(strings.TrimPrefix(fname, filepath.Dir(goModPath))))
+
+	if !isDir {
+		return path.Dir(rel), nil
+	}
+
+	return path.Clean(rel), nil
+}
+
+func getModulePath(goModPath string) string {
+	var pkgPath string
+
+	cacheOkgPath, ok := cache.Load(goModPath)
+	if ok {
+		pkgPath, _ = cacheOkgPath.(string)
+
+		return pkgPath
+	}
+
+	defer func() {
+		cache.Store(goModPath, pkgPath)
+	}()
+
+	data, err := os.ReadFile(goModPath)
+	if err != nil {
+		return ""
+	}
+
+	pkgPath = modulePath(data)
+
+	return pkgPath
+}
+
+func getPkgPathFromGOPATH(fname string, isDir bool) (string, error) {
+	gopath := os.Getenv("GOPATH")
+	if gopath == "" {
+		gopath = build.Default.GOPATH
+	}
+
+	for p := range strings.SplitSeq(gopath, string(filepath.ListSeparator)) {
+		prefix := filepath.Join(p, "src") + string(filepath.Separator)
+
+		rel, err := filepath.Rel(prefix, fname)
+		if err == nil && !strings.HasPrefix(rel, ".."+string(filepath.Separator)) {
+			if !isDir {
+				return path.Dir(filePathToPackagePath(rel)), nil
+			}
+
+			return path.Clean(filePathToPackagePath(rel)), nil
+		}
+	}
+
+	return "", fmt.Errorf("%w: file '%v' is not in GOPATH '%v'", ErrNotFound, fname, gopath)
+}
+
+func filePathToPackagePath(path string) string {
+	return filepath.ToSlash(path)
+}
+
+var (
+	slashSlash = []byte("//")
+	moduleStr  = []byte("module")
+)
+
+// modulePath returns the module path from the gomod file text.
+// If it cannot find a module path, it returns an empty string.
+// It is tolerant of unrelated problems in the go.mod file.
+func modulePath(mod []byte) string {
+	for len(mod) > 0 {
+		line := mod
+
+		mod = nil
+		if i := bytes.IndexByte(line, '\n'); i >= 0 {
+			line, mod = line[:i], line[i+1:]
+		}
+
+		if i := bytes.Index(line, slashSlash); i >= 0 {
+			line = line[:i]
+		}
+
+		line = bytes.TrimSpace(line)
+		if !bytes.HasPrefix(line, moduleStr) {
+			continue
+		}
+
+		line = line[len(moduleStr):]
+		n := len(line)
+
+		line = bytes.TrimSpace(line)
+		if len(line) == n || len(line) == 0 {
+			continue
+		}
+
+		if line[0] == '"' || line[0] == '`' {
+			p, err := strconv.Unquote(string(line))
+			if err != nil {
+				return "" // malformed quoted string or multiline module path
+			}
+
+			return p
+		}
+
+		return string(line)
+	}
+
+	return "" // missing module path
+}

definition/generate/render/data.go

@@ -0,0 +1,61 @@
+package render
+
+import (
+	"gitoa.ru/go-4devs/config/definition/generate/pkg"
+	"gitoa.ru/go-4devs/config/definition/generate/view"
+)
+
+func NewViewData(render Rendering, view view.View) ViewData {
+	return ViewData{
+		Rendering: render,
+		View:      view,
+	}
+}
+
+type ViewData struct {
+	Rendering
+	view.View
+}
+
+func (d ViewData) StructName() string {
+	return d.Rendering.StructName(d.View.StructName())
+}
+
+func (d ViewData) FuncName() string {
+	return d.Rendering.FuncName(d.View.FuncName())
+}
+
+func (d ViewData) ParentStruct() string {
+	name := d.View.ParentStruct()
+	if name == "" {
+		name = d.Name()
+	}
+
+	return d.Rendering.StructName(name)
+}
+
+func (d ViewData) Name() string {
+	return pkg.AliasName(d.View.Name())
+}
+
+func (d ViewData) Type() string {
+	return Type(d)
+}
+
+func (d ViewData) Keys(parent string) string {
+	return Keys(d.View.Keys(), parent)
+}
+
+func (d ViewData) Value(name, val string) string {
+	return Value(name, val, d)
+}
+
+func (d ViewData) Default(name string) string {
+	return Data(d.View.Default(), name, d)
+}
+
+type Rendering interface {
+	StructName(name string) string
+	FuncName(name string) string
+	AddType(pkg string) (string, error)
+}

definition/generate/render/errors.go

@@ -0,0 +1,5 @@
+package render
+
+import "errors"
+
+var ErrNotFound = errors.New("not found")

definition/generate/render/keys.go

@@ -0,0 +1,34 @@
+package render
+
+import (
+	"strings"
+
+	"gitoa.ru/go-4devs/config/definition/generate/pkg"
+	"gitoa.ru/go-4devs/config/key"
+)
+
+func Keys(keys []string, val string) string {
+	if len(keys) == 0 {
+		return ""
+	}
+
+	var out strings.Builder
+
+	for idx, one := range keys {
+		if key.IsWild(one) {
+			out.WriteString(val)
+			out.WriteString(".")
+			out.WriteString(pkg.AliasName(one))
+		} else {
+			out.WriteString("\"")
+			out.WriteString(one)
+			out.WriteString("\"")
+		}
+
+		if len(keys)-1 != idx {
+			out.WriteString(", ")
+		}
+	}
+
+	return out.String()
+}

definition/generate/render/render.go

@@ -0,0 +1,49 @@
+package render
+
+import (
+	"fmt"
+	"io"
+	"reflect"
+
+	"gitoa.ru/go-4devs/config/definition"
+	"gitoa.ru/go-4devs/config/definition/generate/view"
+	"gitoa.ru/go-4devs/config/definition/group"
+	"gitoa.ru/go-4devs/config/definition/option"
+	"gitoa.ru/go-4devs/config/definition/proto"
+)
+
+type Execute func(w io.Writer, vi view.View, rnd Rendering) error
+
+var randders = map[reflect.Type]Execute{
+	reflect.TypeFor[*definition.Definition](): Template(defTpl),
+	reflect.TypeFor[*group.Group]():           Template(groupTpl),
+	reflect.TypeFor[option.Option]():          Template(optTpl),
+	reflect.TypeFor[proto.Proto]():            Template(protoTpl),
+}
+
+func Renders() map[reflect.Type]Execute {
+	return randders
+}
+
+func Add(rt reflect.Type, fn Execute) {
+	randders[rt] = fn
+}
+
+func Render(w io.Writer, view view.View, data Rendering) error {
+	rnd, ok := randders[view.Kind()]
+	if !ok {
+		return fmt.Errorf("%w:%v", ErrNotFound, view.Kind())
+	}
+
+	if err := rnd(w, view, data); err != nil {
+		return fmt.Errorf("render:%v, err:%w", view.Kind(), err)
+	}
+
+	for _, ch := range view.Views() {
+		if err := Render(w, ch, data); err != nil {
+			return fmt.Errorf("render[%v]:%w", ch.Name(), err)
+		}
+	}
+
+	return nil
+}

definition/generate/render/tpl.go

@@ -0,0 +1,41 @@
+package render
+
+import (
+	"embed"
+	"fmt"
+	"io"
+	"strings"
+	"text/template"
+
+	"gitoa.ru/go-4devs/config/definition/generate/view"
+)
+
+//go:embed tpl/*
+var tplFS embed.FS
+
+var (
+	tpls = template.Must(
+		template.New("tpls").
+			Funcs(template.FuncMap{
+				"trim": strings.Trim,
+			}).
+			ParseFS(tplFS, "tpl/*.go.tpl"),
+	)
+	defTpl   = tpls.Lookup("definition.go.tpl")
+	groupTpl = tpls.Lookup("group.go.tpl")
+	protoTpl = tpls.Lookup("proto.go.tpl")
+	optTpl   = template.Must(
+		template.New("opt").ParseFS(tplFS, "tpl/option/option.go.tpl"),
+	).Lookup("option.go.tpl")
+	parceTpls = template.Must(template.New("data").ParseFS(tplFS, "tpl/data/*.go.tpl"))
+)
+
+func Template(tpl *template.Template) Execute {
+	return func(w io.Writer, v view.View, rnd Rendering) error {
+		if err := tpl.Execute(w, NewViewData(rnd, v)); err != nil {
+			return fmt.Errorf("template[%v]:%w", tpl.Name(), err)
+		}
+
+		return nil
+	}
+}

definition/generate/render/tpl/data/any.go.tpl

@@ -0,0 +1,3 @@
+{{block "Any" . }}
+	return {{.ValName}}.Any(), nil
+{{end}}

definition/generate/render/tpl/data/flag_value.go.tpl

@@ -0,0 +1,8 @@
+{{ block "FlagValue" . -}}
+    pval, perr := {{.ValName}}.ParseString()
+    if perr != nil {
+        return {{.Value}}, fmt.Errorf("parse [%v]:%w",[]string{ {{- .Keys "i" -}} }, perr)
+    }
+
+    return {{.Value}}, {{.Value}}.Set(pval)
+{{- end -}}

definition/generate/render/tpl/data/parse.go.tpl

@@ -0,0 +1,3 @@
+{{block "Parse" .}}
+return {{.ValName}}.Parse{{ .FuncType}}()
+{{end}}

definition/generate/render/tpl/data/scan_value.go.tpl

@@ -0,0 +1,3 @@
+{{ block "ScanValue" . -}}
+    return {{.Value}}, {{.Value}}.Scan({{.ValName}}.Any())
+{{- end }}

definition/generate/render/tpl/data/unmarshal_json.go.tpl

@@ -0,0 +1,8 @@
+{{block "UnmarshalJSON" . -}}
+    pval, perr := {{.ValName}}.ParseString()
+    if perr != nil {
+	    return {{.Value}}, fmt.Errorf("parse [%v]:%w", []string{ {{- .Keys "i" -}} }, perr)
+    }
+
+    return {{.Value}}, {{.Value}}.UnmarshalJSON([]byte(pval))
+{{- end -}}

definition/generate/render/tpl/data/unmarshal_text.go.tpl

@@ -0,0 +1,8 @@
+{{ block "UnmarshalText" . -}}
+    pval, perr := {{.ValName}}.ParseString()
+    if perr != nil {
+        return {{.Value}}, fmt.Errorf("parse [%v]:%w", []string{ {{- .Keys "i" -}} }, perr)
+    }
+
+    return {{.Value}}, {{.Value}}.UnmarshalText([]byte(pval))
+{{- end -}}

definition/generate/render/tpl/definition.go.tpl

@@ -0,0 +1,27 @@
+func With{{.StructName}}Handle(fn func(context.Context, error)) func(*{{.StructName}}) {
+	return func(ci *{{.StructName}}) {
+		ci.handle = fn
+	}
+}
+
+func New{{.StructName}}({{if or .SkipContext .ClildSkipContext }} ctx context.Context,{{end}}prov config.Provider, opts ...func(*{{.StructName}})) {{.StructName}} {
+	i := {{.StructName}}{
+		Provider: prov,
+		handle: func(_ context.Context, err error) {
+			fmt.Printf("{{.StructName}}:%v",err)
+		},
+		{{if or .SkipContext .ClildSkipContext }} ctx: ctx, {{end}}
+	}
+
+	for _, opt := range opts {
+		opt(&i)
+	}
+
+	return i
+}
+
+type {{.StructName}} struct {
+	config.Provider
+	handle   func(context.Context, error)
+	{{if or .SkipContext .ClildSkipContext}}ctx context.Context {{end}}
+}

definition/generate/render/tpl/group.go.tpl

@@ -0,0 +1,8 @@
+type {{.StructName}} struct {
+    {{.ParentStruct}}
+}
+
+// {{.FuncName}} {{.Description}}.
+func (i {{.ParentStruct}}) {{.FuncName}}() {{.StructName}} {
+	return {{.StructName}}{i}
+}

definition/generate/render/tpl/option/option.go.tpl

@@ -0,0 +1,30 @@
+// read{{.FuncName}} {{.Description}}.
+func (i {{.ParentStruct}}) read{{.FuncName}}(ctx context.Context) (v {{.Type}},e error) {
+	val, err := i.Value(ctx, {{ .Keys "i" }})
+	if err != nil {
+        {{- if .HasDefault }}
+        i.handle(ctx, err)
+        
+        {{ .Default "val" -}}
+        {{ else }}
+        return v, fmt.Errorf("read [%v]:%w",[]string{ {{- .Keys "i" -}} }, err)
+        {{ end }}
+	}
+
+	{{ .Value "val" "v" }}
+}
+
+// Read{{.FuncName}} {{.Description}}.
+func (i {{.ParentStruct}}) Read{{.FuncName}}({{if not .SkipContext}} ctx context.Context {{end}}) ({{.Type}}, error) {
+    return i.read{{.FuncName}}({{if .SkipContext}}i.ctx{{else}}ctx{{end}})
+}
+
+// {{.FuncName}} {{.Description}}.
+func (i {{.ParentStruct}}) {{.FuncName}}({{if not .SkipContext}} ctx context.Context {{end}}) {{.Type}} {
+    val, err := i.read{{.FuncName}}({{ if .SkipContext }}i.ctx{{else}}ctx{{ end }})
+	if err != nil {
+		i.handle({{ if .SkipContext }}i.ctx{{else}}ctx{{ end }}, err)
+	}
+
+	return val
+}

definition/generate/render/tpl/proto.go.tpl

@@ -0,0 +1,9 @@
+type {{.StructName}} struct {
+    {{.ParentStruct}}
+    {{ .Name }} string
+}
+
+// {{.FuncName}} {{.Description}}.
+func (i {{.ParentStruct}}) {{.FuncName}}(key string) {{.StructName}} {
+	return {{.StructName}}{i,key}
+}

definition/generate/render/value.go

@@ -0,0 +1,266 @@
+package render
+
+import (
+	"bytes"
+	"database/sql"
+	"encoding"
+	"encoding/json"
+	"flag"
+	"fmt"
+	"reflect"
+	"time"
+)
+
+func Value(name, val string, data ViewData) string {
+	rnd := renderType(data)
+
+	res, err := rnd(ValueData{ValName: name, Value: val, ViewData: data})
+	if err != nil {
+		return fmt.Sprintf("render value:%v", err)
+	}
+
+	return res
+}
+
+func Type(data ViewData) string {
+	dt := data.View.Type()
+	rtype := reflect.TypeOf(dt)
+
+	slice := ""
+	if rtype.Kind() == reflect.Slice {
+		slice = "[]"
+		rtype = rtype.Elem()
+	}
+
+	short := rtype.Name()
+
+	if rtype.PkgPath() != "" {
+		var err error
+
+		short, err = data.AddType(rtype.PkgPath() + "." + rtype.Name())
+		if err != nil {
+			return err.Error()
+		}
+	}
+
+	return slice + short
+}
+
+func Data(val any, name string, view ViewData) string {
+	fn := renderData(view)
+
+	data, err := fn(val, ValueData{ValName: name, Value: "", ViewData: view})
+	if err != nil {
+		return fmt.Sprintf("render dara:%v", err)
+	}
+
+	return data
+}
+
+func renderDataTime(val any, _ ValueData) (string, error) {
+	data, _ := val.(time.Time)
+
+	return fmt.Sprintf("time.Parse(%q,time.RFC3339Nano)", data.Format(time.RFC3339Nano)), nil
+}
+
+func renderDataDuration(val any, _ ValueData) (string, error) {
+	data, _ := val.(time.Duration)
+
+	return fmt.Sprintf("time.ParseDuration(%q)", data), nil
+}
+
+func renderDataUnmarhal(val any, view ValueData) (string, error) {
+	res, err := json.Marshal(val)
+	if err != nil {
+		return "", fmt.Errorf("render data unmarshal:%w", err)
+	}
+
+	return fmt.Sprintf("return {{.%[1]s}}, {{.%[1]s}}.UnmarshalJSON(%q)", view.ValName, res), nil
+}
+
+func renderDataUnmarhalText(val any, view ValueData) (string, error) {
+	res, err := json.Marshal(val)
+	if err != nil {
+		return "", fmt.Errorf("render data unmarshal:%w", err)
+	}
+
+	return fmt.Sprintf("return {{.%[1]s}}, {{.%[1]s}}.UnmarshalText(%s)", view.ValName, res), nil
+}
+
+func renderDataFlag(val any, view ValueData) (string, error) {
+	return fmt.Sprintf("return {{.%[1]s}}, {{.%[1]s}}.Set(%[2]q)", view.ValName, val), nil
+}
+
+func renderType(view ViewData) func(data ValueData) (string, error) {
+	return dataRender(view).Type
+}
+
+func renderData(view ViewData) func(in any, data ValueData) (string, error) {
+	return dataRender(view).Value
+}
+
+func dataRender(view ViewData) DataRender {
+	data := view.View.Type()
+	vtype := reflect.TypeOf(data)
+
+	if vtype.Kind() == reflect.Slice {
+		return render[reflect.TypeFor[json.Unmarshaler]()]
+	}
+
+	if h, ok := render[vtype]; ok {
+		return h
+	}
+
+	if vtype.Kind() != reflect.Interface && vtype.Kind() != reflect.Pointer {
+		vtype = reflect.PointerTo(vtype)
+	}
+
+	for extypes := range render {
+		if extypes == nil || extypes.Kind() != reflect.Interface {
+			continue
+		}
+
+		if vtype.Implements(extypes) {
+			return render[extypes]
+		}
+	}
+
+	return render[reflect.TypeOf((any)(nil))]
+}
+
+//nolint:gochecknoglobals
+var render = map[reflect.Type]DataRender{
+	reflect.TypeFor[encoding.TextUnmarshaler](): NewDataRender(unmarshalTextType, renderDataUnmarhalText),
+	reflect.TypeFor[json.Unmarshaler]():         NewDataRender(unmarshalType, renderDataUnmarhal),
+	reflect.TypeFor[flag.Value]():               NewDataRender(flagType, renderDataFlag),
+	reflect.TypeFor[sql.Scanner]():              NewDataRender(scanType, nil),
+	reflect.TypeFor[int]():                      NewDataRender(internalType, nil),
+	reflect.TypeFor[int64]():                    NewDataRender(internalType, anyValue),
+	reflect.TypeFor[bool]():                     NewDataRender(internalType, anyValue),
+	reflect.TypeFor[string]():                   NewDataRender(internalType, anyValue),
+	reflect.TypeFor[float64]():                  NewDataRender(internalType, anyValue),
+	reflect.TypeFor[uint]():                     NewDataRender(internalType, anyValue),
+	reflect.TypeFor[int64]():                    NewDataRender(internalType, anyValue),
+	reflect.TypeFor[time.Duration]():            NewDataRender(durationType, renderDataDuration),
+	reflect.TypeFor[time.Time]():                NewDataRender(timeType, renderDataTime),
+	reflect.TypeOf((any)(nil)):                  NewDataRender(anyType, anyValue),
+}
+
+func timeType(data ValueData) (string, error) {
+	return fmt.Sprintf("return %s.ParseTime()", data.ValName), nil
+}
+
+func durationType(data ValueData) (string, error) {
+	return fmt.Sprintf("return %s.ParseDuration()", data.ValName), nil
+}
+
+func scanType(data ValueData) (string, error) {
+	var b bytes.Buffer
+
+	err := parceTpls.Lookup("scan_value.go.tpl").Execute(&b, data)
+	if err != nil {
+		return "", fmt.Errorf("execute scan value:%w", err)
+	}
+
+	return b.String(), nil
+}
+
+func flagType(data ValueData) (string, error) {
+	var b bytes.Buffer
+
+	err := parceTpls.Lookup("flag_value.go.tpl").Execute(&b, data)
+	if err != nil {
+		return "", fmt.Errorf("execute flag value:%w", err)
+	}
+
+	return b.String(), nil
+}
+
+func anyType(data ValueData) (string, error) {
+	var b bytes.Buffer
+
+	err := parceTpls.ExecuteTemplate(&b, "any.go.tpl", data)
+	if err != nil {
+		return "", fmt.Errorf("unmarshal execute any.go.tpl:%w", err)
+	}
+
+	return b.String(), nil
+}
+
+func anyValue(data any, _ ValueData) (string, error) {
+	return fmt.Sprintf("return %#v, nil", data), nil
+}
+
+func unmarshalType(data ValueData) (string, error) {
+	var b bytes.Buffer
+
+	err := parceTpls.ExecuteTemplate(&b, "unmarshal_json.go.tpl", data)
+	if err != nil {
+		return "", fmt.Errorf("unmarshal execute unmarshal_json.go.tpl:%w", err)
+	}
+
+	return b.String(), nil
+}
+
+func unmarshalTextType(data ValueData) (string, error) {
+	var b bytes.Buffer
+
+	err := parceTpls.Lookup("unmarshal_text.go.tpl").Execute(&b, data)
+	if err != nil {
+		return "", fmt.Errorf("execute unmarshal text:%w", err)
+	}
+
+	return b.String(), nil
+}
+
+func internalType(data ValueData) (string, error) {
+	var b bytes.Buffer
+
+	err := parceTpls.Lookup("parse.go.tpl").Execute(&b, data)
+	if err != nil {
+		return "", fmt.Errorf("internal execute parce.go.tpl:%w", err)
+	}
+
+	return b.String(), nil
+}
+
+type ValueData struct {
+	ViewData
+
+	ValName string
+	Value   string
+}
+
+func (v ValueData) FuncType() string {
+	name := reflect.TypeOf(v.ViewData.Type()).Name()
+
+	return v.Rendering.FuncName(name)
+}
+
+type DataRender struct {
+	renderType  func(data ValueData) (string, error)
+	renderValue func(data any, view ValueData) (string, error)
+}
+
+func (d DataRender) Type(data ValueData) (string, error) {
+	return d.renderType(data)
+}
+
+func (d DataRender) Value(data any, view ValueData) (string, error) {
+	return d.renderValue(data, view)
+}
+
+func NewDataRender(rendeType func(data ValueData) (string, error), renderValue func(data any, view ValueData) (string, error)) DataRender {
+	if rendeType == nil {
+		rendeType = anyType
+	}
+
+	if renderValue == nil {
+		renderValue = anyValue
+	}
+
+	return DataRender{
+		renderType:  rendeType,
+		renderValue: renderValue,
+	}
+}

definition/generate/render/value_test.go

@@ -0,0 +1,129 @@
+package render_test
+
+import (
+	"fmt"
+	"strconv"
+	"testing"
+
+	"gitoa.ru/go-4devs/config/definition/generate/render"
+	"gitoa.ru/go-4devs/config/definition/generate/view"
+	"gitoa.ru/go-4devs/config/definition/option"
+)
+
+type flagValue int
+
+func (f flagValue) String() string {
+	return strconv.Itoa(int(f))
+}
+
+func (f *flagValue) Set(in string) error {
+	data, err := strconv.Atoi(in)
+	if err != nil {
+		return fmt.Errorf("%w", err)
+	}
+
+	*f = flagValue(data)
+
+	return nil
+}
+
+func TestValue_FlagType(t *testing.T) {
+	t.Parallel()
+
+	const ex = `pval, perr := val.ParseString()
+    if perr != nil {
+        return v, fmt.Errorf("parse [%v]:%w",[]string{"flag_value"}, perr)
+    }
+
+    return v, v.Set(pval)`
+
+	viewData := render.NewViewData(nil, view.NewView(option.New("flag_value", "flag desc", flagValue(0))))
+	result := render.Value("val", "v", viewData)
+
+	if result != ex {
+		t.Errorf("failed render flag type ex:%s, res:%s", ex, result)
+	}
+}
+
+func TestData_Flag(t *testing.T) {
+	t.Parallel()
+
+	const ex = `return {{.val}}, {{.val}}.Set("42")`
+
+	viewData := render.NewViewData(nil, view.NewView(option.New("flag_value", "flag desc", flagValue(0))))
+	result := render.Data(flagValue(42), "val", viewData)
+
+	if result != ex {
+		t.Errorf("failed render flag value ex:%s, res:%s", ex, result)
+	}
+}
+
+type scanValue int
+
+func (s *scanValue) Scan(src any) error {
+	res, _ := src.(string)
+
+	data, err := strconv.Atoi(res)
+	if err != nil {
+		return fmt.Errorf("%w", err)
+	}
+
+	*s = scanValue(data)
+
+	return nil
+}
+
+func TestValue_Scan(t *testing.T) {
+	t.Parallel()
+
+	const ex = `return v, v.Scan(val.Any())`
+
+	viewData := render.NewViewData(nil, view.NewView(option.New("scan_value", "scan desc", scanValue(42))))
+	result := render.Value("val", "v", viewData)
+
+	if result != ex {
+		t.Errorf("failed render flag value ex:%s, res:%s", ex, result)
+	}
+}
+
+type textData string
+
+func (j *textData) UnmarshalText(in []byte) error {
+	val := string(in)
+
+	*j = textData(val)
+
+	return nil
+}
+
+func TestData_UnmarshalText(t *testing.T) {
+	t.Parallel()
+
+	const ex = `return {{.val}}, {{.val}}.UnmarshalText("4devs")`
+
+	data := textData("4devs")
+	viewData := render.NewViewData(nil, view.NewView(option.New("tvalue", "unmarshal text desc", textData(""))))
+	result := render.Data(data, "val", viewData)
+
+	if result != ex {
+		t.Errorf("failed render flag value ex:%s, res:%s", ex, result)
+	}
+}
+
+func TestValue_UnmarshalText(t *testing.T) {
+	t.Parallel()
+
+	const ex = `pval, perr := val.ParseString()
+    if perr != nil {
+        return v, fmt.Errorf("parse [%v]:%w", []string{"tvalue"}, perr)
+    }
+
+    return v, v.UnmarshalText([]byte(pval))`
+
+	viewData := render.NewViewData(nil, view.NewView(option.New("tvalue", "unmarshal text desc", textData(""))))
+	result := render.Value("val", "v", viewData)
+
+	if result != ex {
+		t.Errorf("failed render flag value ex:%s, res:%s", ex, result)
+	}
+}

definition/generate/tpl/init.go.tpl

@@ -0,0 +1,8 @@
+// Code generated gitoa.ru/go-4devs/config DO NOT EDIT.
+package {{.Pkg}}
+
+import (
+    {{range .Imports}}
+    {{- . }}
+    {{end}}
+)

definition/generate/view/view.go

@@ -0,0 +1,250 @@
+package view
+
+import (
+	"fmt"
+	"reflect"
+	"strings"
+
+	"gitoa.ru/go-4devs/config"
+	"gitoa.ru/go-4devs/config/definition/option"
+	"gitoa.ru/go-4devs/config/param"
+)
+
+type key int
+
+const (
+	viewParamFunctName key = iota + 1
+	viewParamSkipContext
+	viewParamStructName
+	viewParamStructPrefix
+	viewParamStructSuffix
+)
+
+func WithStructName(name string) param.Option {
+	return func(p param.Params) param.Params {
+		return param.With(p, viewParamStructName, name)
+	}
+}
+
+func WithStructPrefix(prefix string) param.Option {
+	return func(p param.Params) param.Params {
+		return param.With(p, viewParamStructPrefix, prefix)
+	}
+}
+
+func WithStructSuffix(suffix string) param.Option {
+	return func(p param.Params) param.Params {
+		return param.With(p, viewParamStructSuffix, suffix)
+	}
+}
+
+func WithSkipContext(p param.Params) param.Params {
+	return param.With(p, viewParamSkipContext, true)
+}
+
+func WithContext(p param.Params) param.Params {
+	return param.With(p, viewParamSkipContext, false)
+}
+
+func IsSkipContext(p param.Params) bool {
+	data, has := p.Param(viewParamSkipContext)
+
+	if has {
+		skip, ok := data.(bool)
+
+		return ok && skip
+	}
+
+	return false
+}
+
+type Option func(*View)
+
+func WithParent(in *View) Option {
+	return func(v *View) {
+		v.parent = in
+	}
+}
+
+func NewViews(option config.Options, opts ...Option) View {
+	view := newView(option, opts...)
+
+	for _, op := range option.Options() {
+		view.children = append(view.children, NewView(op, WithParent(&view)))
+	}
+
+	return view
+}
+
+func newView(params param.Params, opts ...Option) View {
+	vi := View{
+		Params:   params,
+		parent:   nil,
+		children: nil,
+	}
+
+	for _, opt := range opts {
+		opt(&vi)
+	}
+
+	return vi
+}
+
+func NewView(opt config.Option, opts ...Option) View {
+	vi := newView(opt, opts...)
+
+	if data, ok := opt.(config.Group); ok {
+		for _, chi := range data.Options() {
+			vi.children = append(vi.children, NewView(chi, WithParent(&vi)))
+		}
+	}
+
+	return vi
+}
+
+type View struct {
+	param.Params
+
+	children []View
+	parent   *View
+}
+
+func (v View) Types() []any {
+	types := make([]any, 0)
+	if v.Type() != "" {
+		types = append(types, v.Type())
+	}
+
+	for _, child := range v.children {
+		types = append(types, child.Types()...)
+	}
+
+	return types
+}
+
+func (v View) Kind() reflect.Type {
+	return reflect.TypeOf(v.Params)
+}
+
+func (v View) Views() []View {
+	return v.children
+}
+
+func (v View) Param(key any) string {
+	data, has := v.Params.Param(key)
+	if has {
+		return fmt.Sprintf("%v", data)
+	}
+
+	if v.parent != nil {
+		return v.parent.Param(key)
+	}
+
+	return ""
+}
+
+func (v View) ClildSkipContext() bool {
+	for _, child := range v.children {
+		if child.SkipContext() {
+			return true
+		}
+	}
+
+	return false
+}
+
+func (v View) SkipContext() bool {
+	if IsSkipContext(v.Params) {
+		return true
+	}
+
+	if v.parent != nil {
+		return v.parent.SkipContext()
+	}
+
+	return false
+}
+
+func (v View) Name() string {
+	if data, ok := v.Params.(interface{ Name() string }); ok {
+		return data.Name()
+	}
+
+	return ""
+}
+
+func (v View) Keys() []string {
+	keys := make([]string, 0, 1)
+	if v.parent != nil {
+		keys = append(keys, v.parent.Keys()...)
+	}
+
+	if name := v.Name(); name != "" {
+		keys = append(keys, name)
+	}
+
+	return keys
+}
+
+func (v View) Type() any {
+	return param.Type(v.Params)
+}
+
+func (v View) FuncName() string {
+	data, ok := v.Params.Param(viewParamFunctName)
+	name, valid := data.(string)
+
+	if !ok || !valid {
+		return v.Name()
+	}
+
+	return name
+}
+
+func (v View) StructName() string {
+	name, ok := param.String(v.Params, viewParamStructName)
+	if ok {
+		return name
+	}
+
+	keys := make([]string, 0, len(v.Keys())+2) //nolint:mnd
+
+	prefix := v.Param(viewParamStructPrefix)
+	if prefix != "" {
+		keys = append(keys, prefix)
+	}
+
+	keys = append(keys, v.Keys()...)
+
+	suffix := v.Param(viewParamStructSuffix)
+	if suffix != "" {
+		keys = append(keys, suffix)
+	}
+
+	return strings.Join(keys, "_")
+}
+
+func (v View) ParentStruct() string {
+	if v.parent == nil {
+		return ""
+	}
+
+	return v.parent.StructName()
+}
+
+func (v View) Description() string {
+	return param.Description(v.Params)
+}
+
+func (v View) Default() any {
+	data, ok := param.Default(v.Params)
+	if !ok {
+		return nil
+	}
+
+	return data
+}
+
+func (v View) HasDefault() bool {
+	return option.HasDefaut(v.Params)
+}

definition/group/group.go

@@ -0,0 +1,44 @@
+package group
+
+import (
+	"gitoa.ru/go-4devs/config"
+	"gitoa.ru/go-4devs/config/param"
+)
+
+var _ config.Group = New("", "")
+
+func New(name, desc string, opts ...config.Option) *Group {
+	group := Group{
+		name:   name,
+		opts:   opts,
+		Params: param.New(param.WithDescription(desc)),
+	}
+
+	return &group
+}
+
+type Group struct {
+	param.Params
+
+	name string
+	opts []config.Option
+}
+
+func (g *Group) Name() string {
+	return g.name
+}
+
+func (g *Group) Options() []config.Option {
+	return g.opts
+}
+
+func (g *Group) Add(opts ...config.Option) {
+	g.opts = append(g.opts, opts...)
+}
+
+func (g *Group) With(opts ...param.Option) *Group {
+	group := New(g.Name(), "")
+	group.Params = param.Chain(g.Params, param.New(opts...))
+
+	return group
+}

definition/group/group_test.go

@@ -0,0 +1,29 @@
+package group_test
+
+import (
+	"testing"
+
+	"gitoa.ru/go-4devs/config/definition/group"
+	"gitoa.ru/go-4devs/config/param"
+	"gitoa.ru/go-4devs/config/test/require"
+)
+
+func TestGroupAdd(t *testing.T) {
+	t.Parallel()
+
+	var gr group.Group
+
+	gr.Add(group.New("test", "test"))
+	require.Truef(t, len(gr.Options()) == 1, "len(%v) != 1", len(gr.Options()))
+}
+
+func TestGroupWith(t *testing.T) {
+	t.Parallel()
+
+	const descrition = "group description"
+
+	gr := group.New("test", "test desc")
+	gr = gr.With(param.WithDescription(descrition))
+
+	require.Equal(t, descrition, param.Description(gr))
+}

definition/option/errors.go

@@ -0,0 +1,30 @@
+package option
+
+import (
+	"errors"
+	"fmt"
+)
+
+type Error struct {
+	Key []string
+	Err error
+}
+
+func (o Error) Error() string {
+	return fmt.Sprintf("%s: %s", o.Key, o.Err)
+}
+
+func (o Error) Is(err error) bool {
+	return errors.Is(err, o.Err)
+}
+
+func (o Error) Unwrap() error {
+	return o.Err
+}
+
+func Err(err error, key []string) Error {
+	return Error{
+		Key: key,
+		Err: err,
+	}
+}

definition/option/option.go

@@ -0,0 +1,66 @@
+package option
+
+import (
+	"time"
+
+	"gitoa.ru/go-4devs/config"
+	"gitoa.ru/go-4devs/config/param"
+)
+
+var _ config.Option = New("", "", nil)
+
+func New(name, desc string, vtype any, opts ...param.Option) Option {
+	opts = append(opts, param.WithDescription(desc), WithType(vtype))
+	res := Option{
+		name:   name,
+		Params: param.New(opts...),
+	}
+
+	return res
+}
+
+type Option struct {
+	param.Params
+
+	name string
+}
+
+func (o Option) Name() string {
+	return o.name
+}
+
+func String(name, description string, opts ...param.Option) Option {
+	return New(name, description, "", opts...)
+}
+
+func Bool(name, description string, opts ...param.Option) Option {
+	return New(name, description, false, opts...)
+}
+
+func Duration(name, description string, opts ...param.Option) Option {
+	return New(name, description, time.Duration(0), opts...)
+}
+
+func Float64(name, description string, opts ...param.Option) Option {
+	return New(name, description, float64(0), opts...)
+}
+
+func Int(name, description string, opts ...param.Option) Option {
+	return New(name, description, int(0), opts...)
+}
+
+func Int64(name, description string, opts ...param.Option) Option {
+	return New(name, description, int64(0), opts...)
+}
+
+func Time(name, description string, opts ...param.Option) Option {
+	return New(name, description, time.Time{}, opts...)
+}
+
+func Uint(name, description string, opts ...param.Option) Option {
+	return New(name, description, uint(0), opts...)
+}
+
+func Uint64(name, descriontion string, opts ...param.Option) Option {
+	return New(name, descriontion, uint64(0), opts...)
+}

definition/option/params.go

@@ -0,0 +1,118 @@
+package option
+
+import (
+	"gitoa.ru/go-4devs/config/param"
+)
+
+type key int
+
+const (
+	paramHidden key = iota + 1
+	paramRequired
+	paramSlice
+	paramBool
+	paramShort
+)
+
+func Short(in rune) param.Option {
+	return func(v param.Params) param.Params {
+		return param.With(v, paramShort, string(in))
+	}
+}
+
+func ParamShort(fn param.Params) (string, bool) {
+	data, ok := param.String(fn, paramShort)
+
+	return data, ok
+}
+
+func HasShort(short string) param.Has {
+	return func(fn param.Params) bool {
+		data, ok := param.String(fn, paramShort)
+
+		return ok && data == short
+	}
+}
+
+func WithType(in any) param.Option {
+	return func(v param.Params) param.Params {
+		out := param.WithType(in)(v)
+		if _, ok := in.(bool); ok {
+			return param.With(out, paramBool, ok)
+		}
+
+		return out
+	}
+}
+
+func Position(pos uint64) param.Option {
+	return param.WithPostition(pos)
+}
+
+func Hidden(v param.Params) param.Params {
+	return param.With(v, paramHidden, true)
+}
+
+func Required(v param.Params) param.Params {
+	return param.With(v, paramRequired, true)
+}
+
+func Slice(v param.Params) param.Params {
+	return param.With(v, paramSlice, true)
+}
+
+func Default(in any) param.Option {
+	return param.WithDefault(in)
+}
+
+// Deprecated: use param.WithDescription.
+func Description(in string) param.Option {
+	return param.WithDescription(in)
+}
+
+func HasDefaut(fn param.Params) bool {
+	_, ok := param.Default(fn)
+
+	return ok
+}
+
+// Deprecated: use param.Position.
+func DataPosition(fn param.Params) (uint64, bool) {
+	pos := param.Position(fn)
+
+	return pos, pos != 0
+}
+
+// Deprecated: use param.Default.
+func DataDefaut(fn param.Params) (any, bool) {
+	return param.Default(fn)
+}
+
+func IsSlice(fn param.Params) bool {
+	data, ok := param.Bool(paramSlice, fn)
+
+	return ok && data
+}
+
+func IsBool(fn param.Params) bool {
+	data, ok := param.Bool(paramBool, fn)
+
+	return ok && data
+}
+
+func IsHidden(fn param.Params) bool {
+	data, ok := param.Bool(paramHidden, fn)
+
+	return ok && data
+}
+
+func IsRequired(fn param.Params) bool {
+	data, ok := param.Bool(paramRequired, fn)
+
+	return ok && data
+}
+
+// Deprecated: use param.Description.
+func DataDescription(fn param.Params) string {
+	return param.Description(fn)
+}

definition/proto/proto.go

@@ -0,0 +1,32 @@
+package proto
+
+import (
+	"gitoa.ru/go-4devs/config"
+	"gitoa.ru/go-4devs/config/key"
+	"gitoa.ru/go-4devs/config/param"
+)
+
+var _ config.Group = New("", "")
+
+func New(name string, desc string, opts ...config.Option) Proto {
+	return Proto{
+		name:   key.Wild(name),
+		opts:   opts,
+		Params: param.New(param.WithDescription(desc)),
+	}
+}
+
+type Proto struct {
+	param.Params
+
+	opts []config.Option
+	name string
+}
+
+func (p Proto) Options() []config.Option {
+	return p.opts
+}
+
+func (p Proto) Name() string {
+	return p.name
+}

error.go

@@ -1,11 +1,20 @@
 package config
 
-import "errors"
+import (
+	"errors"
+	"fmt"
+)
 
 var (
-	ErrValueNotFound = errors.New("value not found")
-	ErrInvalidValue  = errors.New("invalid value")
-	ErrUnknowType    = errors.New("unknow type")
-	ErrInitFactory   = errors.New("init factory")
-	ErrStopWatch     = errors.New("stop watch")
+	ErrInvalidValue   = errors.New("invalid value")
+	ErrUnknowType     = errors.New("unknow type")
+	ErrInitFactory    = errors.New("init factory")
+	ErrStopWatch      = errors.New("stop watch")
+	ErrNotFound       = errors.New("not found")
+	ErrValueNotFound  = fmt.Errorf("value %w", ErrNotFound)
+	ErrToManyArgs     = errors.New("to many args")
+	ErrWrongType      = errors.New("wrong type")
+	ErrInvalidName    = errors.New("ivalid name")
+	ErrUnexpectedType = errors.New("unexpected type")
+	ErrRequired       = errors.New("required")
 )

factory.go

@@ -0,0 +1,96 @@
+package config
+
+import (
+	"context"
+	"fmt"
+	"sync"
+	"sync/atomic"
+)
+
+func WrapFactory(fn Factory, prov Provider) *WrapProvider {
+	return &WrapProvider{
+		factory: func(ctx context.Context) (Provider, error) {
+			return fn.Create(ctx, prov)
+		},
+		mu:       sync.Mutex{},
+		done:     0,
+		provider: nil,
+		name:     fn.Name(),
+	}
+}
+
+type WrapProvider struct {
+	mu       sync.Mutex
+	done     uint32
+	provider Provider
+	factory  func(ctx context.Context) (Provider, error)
+	name     string
+}
+
+func (p *WrapProvider) Watch(ctx context.Context, callback WatchCallback, path ...string) error {
+	if err := p.init(ctx); err != nil {
+		return fmt.Errorf("init read:%w", err)
+	}
+
+	watch, ok := p.provider.(WatchProvider)
+	if !ok {
+		return nil
+	}
+
+	if err := watch.Watch(ctx, callback, path...); err != nil {
+		return fmt.Errorf("factory provider: %w", err)
+	}
+
+	return nil
+}
+
+func (p *WrapProvider) Value(ctx context.Context, path ...string) (Value, error) {
+	if err := p.init(ctx); err != nil {
+		return nil, fmt.Errorf("init read:%w", err)
+	}
+
+	variable, err := p.provider.Value(ctx, path...)
+	if err != nil {
+		return nil, fmt.Errorf("factory provider: %w", err)
+	}
+
+	return variable, nil
+}
+
+func (p *WrapProvider) Name() string {
+	return p.name
+}
+
+func (p *WrapProvider) Bind(ctx context.Context, data Variables) error {
+	if err := p.init(ctx); err != nil {
+		return fmt.Errorf("init bind: %w", err)
+	}
+
+	prov, ok := p.provider.(BindProvider)
+	if !ok {
+		return nil
+	}
+
+	if perr := prov.Bind(ctx, data); perr != nil {
+		return fmt.Errorf("init bind provider: %w", perr)
+	}
+
+	return nil
+}
+
+func (p *WrapProvider) init(ctx context.Context) error {
+	if atomic.LoadUint32(&p.done) == 0 {
+		if !p.mu.TryLock() {
+			return fmt.Errorf("%w", ErrInitFactory)
+		}
+		defer atomic.StoreUint32(&p.done, 1)
+		defer p.mu.Unlock()
+
+		var err error
+		if p.provider, err = p.factory(ctx); err != nil {
+			return fmt.Errorf("init provider factory:%w", err)
+		}
+	}
+
+	return nil
+}

go.mod

@@ -1,3 +1,5 @@
 module gitoa.ru/go-4devs/config
 
-go 1.21
+go 1.24.0
+
+require gitoa.ru/go-4devs/console v0.2.0

go.sum

@@ -0,0 +1,2 @@
+gitoa.ru/go-4devs/console v0.2.0 h1:6lsbArs99GA8vGdnwNDThZNKjFNctNtTlSCUjhgwIpU=
+gitoa.ru/go-4devs/console v0.2.0/go.mod h1:xi4Svw7T+lylckAQiJQS/2qwDwF4YbIanlhcbQrBAiI=

key/map.go

@@ -0,0 +1,125 @@
+package key
+
+import (
+	"strings"
+)
+
+const (
+	prefixByPath = "byPath"
+	wrongIDx     = -1
+)
+
+func newMap() *Map {
+	return &Map{
+		idx:      wrongIDx,
+		wild:     nil,
+		children: nil,
+	}
+}
+
+type Map struct {
+	idx      int
+	wild     *Map
+	children map[string]*Map
+}
+
+func ByPath(name, sep string) []string {
+	return []string{prefixByPath, name, sep}
+}
+
+func (m *Map) Index(path []string) (int, bool) {
+	if data, ok := m.find(path); ok {
+		return data.idx, true
+	}
+
+	if len(path) == 3 && path[0] == prefixByPath {
+		data, ok := m.byPath(path[1], path[2])
+
+		return data.idx, ok
+	}
+
+	return 0, false
+}
+
+func (m *Map) Add(idx int, path []string) {
+	m.add(path).idx = idx
+}
+
+func (m *Map) add(path []string) *Map {
+	name, path := path[0], path[1:]
+
+	if IsWild(name) {
+		m.wild = newMap()
+
+		return m.wild.add(path)
+	}
+
+	if m.children == nil {
+		m.children = map[string]*Map{}
+	}
+
+	if _, ok := m.children[name]; !ok {
+		m.children[name] = newMap()
+	}
+
+	if len(path) > 0 {
+		return m.children[name].add(path)
+	}
+
+	return m.children[name]
+}
+
+func (m *Map) byPath(path, sep string) (*Map, bool) {
+	if len(path) == 0 {
+		return m, m.isValid()
+	}
+
+	for name := range m.children {
+		if after, ok := strings.CutPrefix(path, name); ok {
+			data := m.children[name]
+			if len(after) == 0 || len(after) == len(sep) {
+				return data, data.isValid()
+			}
+
+			return data.byPath(after[len(sep):], sep)
+		}
+	}
+
+	if m.wild == nil {
+		return m, m.isValid()
+	}
+
+	if idx := strings.Index(path, sep); idx != -1 {
+		return m.wild.byPath(path[idx+1:], sep)
+	}
+
+	return m, m.isValid()
+}
+
+func (m *Map) find(path []string) (*Map, bool) {
+	name := path[0]
+
+	last := len(path) == 1
+	if !last {
+		path = path[1:]
+	}
+
+	data, ok := m.children[name]
+	if !ok && m.wild != nil {
+		return m.wild.find(path)
+	}
+
+	if !ok {
+		return data, false
+	}
+
+	if last {
+		return data, data.isValid()
+	}
+
+	return data.find(path)
+}
+
+func (m *Map) isValid() bool {
+	return m.idx != wrongIDx
+}

key/map_test.go

@@ -0,0 +1,101 @@
+package key_test
+
+import (
+	"testing"
+
+	"gitoa.ru/go-4devs/config/key"
+)
+
+func TestMap_ByPath(t *testing.T) {
+	t.Parallel()
+
+	const (
+		expID int = 1
+		othID int = 0
+		newID int = 42
+		grpID int = 27
+	)
+
+	data := key.Map{}
+	data.Add(expID, []string{"test", "data", "three"})
+	data.Add(othID, []string{"test", "other"})
+	data.Add(newID, []string{"new", "{data}", "test"})
+	data.Add(grpID, []string{"new", "group"})
+
+	idx, ok := data.Index(key.ByPath("test-other", "-"))
+	if !ok {
+		t.Error("key not found")
+	}
+
+	if idx != othID {
+		t.Errorf("idx exp:%v got:%v", othID, idx)
+	}
+
+	if nidx, nok := data.Index(key.ByPath("new-service-test", "-")); !nok && nidx != newID {
+		t.Errorf("idx exp:%v got:%v", newID, nidx)
+	}
+
+	if gidx, gok := data.Index(key.ByPath("new-group", "-")); !gok && gidx != grpID {
+		t.Errorf("idx %v exp:%v got:%v", gok, grpID, gidx)
+	}
+}
+
+func TestMap_Add(t *testing.T) {
+	t.Parallel()
+
+	const (
+		expID int = 1
+		newID int = 42
+	)
+
+	data := key.Map{}
+	data.Add(expID, []string{"test", "data"})
+	data.Add(expID, []string{"test", "other"})
+	data.Add(newID, []string{"new"})
+
+	idx, ok := data.Index([]string{"test", "data"})
+	if !ok {
+		t.Error("key not found")
+	}
+
+	if idx != expID {
+		t.Errorf("idx exp:%v got:%v", expID, idx)
+	}
+
+	if nidx, nok := data.Index([]string{"new"}); !nok && nidx != newID {
+		t.Errorf("idx exp:%v got:%v", newID, nidx)
+	}
+}
+
+func TestMap_Wild(t *testing.T) {
+	t.Parallel()
+
+	const (
+		expID int = 1
+		grpID int = 27
+		newID int = 42
+	)
+
+	data := key.Map{}
+	data.Add(expID, []string{"test", "{data}", "id"})
+	data.Add(grpID, []string{"test", "group"})
+	data.Add(newID, []string{"new", "data"})
+
+	idx, ok := data.Index([]string{"test", "data", "id"})
+	if !ok {
+		t.Error("key not found")
+	}
+
+	if idx != expID {
+		t.Errorf("idx exp:%v got:%v", expID, idx)
+	}
+
+	gidx, gok := data.Index([]string{"test", "group"})
+	if !gok {
+		t.Error("key not found")
+	}
+
+	if gidx != grpID {
+		t.Errorf("idx exp:%v got:%v", grpID, idx)
+	}
+}

key/wild.go

@@ -0,0 +1,21 @@
+package key
+
+import "slices"
+
+const minWildCount = 3
+
+func IsWild(keys ...string) bool {
+	return slices.ContainsFunc(keys, isWild)
+}
+
+func Wild(name string) string {
+	return "{" + name + "}"
+}
+
+func isWild(name string) bool {
+	if len(name) < minWildCount {
+		return false
+	}
+
+	return name[0] == '{' && name[len(name)-1] == '}'
+}

key/wild_test.go

@@ -0,0 +1,16 @@
+package key_test
+
+import (
+	"testing"
+
+	"gitoa.ru/go-4devs/config/key"
+	"gitoa.ru/go-4devs/config/test/require"
+)
+
+func TestWild(t *testing.T) {
+	t.Parallel()
+
+	require.True(t, key.IsWild(key.Wild("test")))
+	require.True(t, !key.IsWild("test"))
+	require.True(t, key.IsWild("test", key.Wild("test"), "key"))
+}

param/helper.go

@@ -0,0 +1,45 @@
+package param
+
+func String(fn Params, key any) (string, bool) {
+	val, ok := fn.Param(key)
+	if !ok {
+		return "", false
+	}
+
+	data, ok := val.(string)
+
+	return data, ok
+}
+
+func Rune(fn Params, key any) (rune, bool) {
+	val, ok := fn.Param(key)
+	if !ok {
+		return '0', false
+	}
+
+	data, dok := val.(rune)
+
+	return data, dok
+}
+
+func Bool(key any, fn Params) (bool, bool) {
+	val, ok := fn.Param(key)
+	if !ok {
+		return false, false
+	}
+
+	data, ok := val.(bool)
+
+	return data, ok
+}
+
+func Uint64(key any, fn Params) (uint64, bool) {
+	data, ok := fn.Param(key)
+	if !ok {
+		return 0, false
+	}
+
+	res, ok := data.(uint64)
+
+	return res, ok
+}

param/keys.go

@@ -0,0 +1,69 @@
+package param
+
+type key int
+
+const (
+	paramTimeFormat key = iota + 1
+	paramType
+	paramDescription
+	paramDefault
+	paramPosition
+)
+
+func WithTimeFormat(format string) Option {
+	return func(p Params) Params {
+		return With(p, paramTimeFormat, format)
+	}
+}
+
+func TimeFormat(fn Params) (string, bool) {
+	return String(fn, paramTimeFormat)
+}
+
+func WithType(in any) Option {
+	return func(v Params) Params {
+		return With(v, paramType, in)
+	}
+}
+
+func Type(fn Params) any {
+	param, _ := fn.Param(paramType)
+
+	return param
+}
+
+func WithDescription(in string) Option {
+	return func(p Params) Params {
+		return With(p, paramDescription, in)
+	}
+}
+
+func Description(fn Params) string {
+	data, _ := String(fn, paramDescription)
+
+	return data
+}
+
+func WithDefault(in any) Option {
+	return func(p Params) Params {
+		return With(p, paramDefault, in)
+	}
+}
+
+func Default(p Params) (any, bool) {
+	data, ok := p.Param(paramDefault)
+
+	return data, ok
+}
+
+func WithPostition(in uint64) Option {
+	return func(p Params) Params {
+		return With(p, paramPosition, in)
+	}
+}
+
+func Position(in Params) uint64 {
+	pos, _ := Uint64(paramPosition, in)
+
+	return pos
+}

param/param.go

@@ -0,0 +1,74 @@
+package param
+
+import (
+	"slices"
+)
+
+var emptyParam = empty{}
+
+type (
+	Option func(p Params) Params
+	Has    func(Params) bool
+	Params interface {
+		Param(key any) (any, bool)
+	}
+)
+
+func Chain(vals ...Params) Params {
+	slices.Reverse(vals)
+
+	return chain(vals)
+}
+
+func With(parent Params, key, val any) Params {
+	return value{
+		Params: parent,
+		key:    key,
+		val:    val,
+	}
+}
+
+func New(opts ...Option) Params {
+	var parms Params
+
+	parms = emptyParam
+
+	for _, opt := range opts {
+		parms = opt(parms)
+	}
+
+	return parms
+}
+
+type empty struct{}
+
+func (v empty) Param(_ any) (any, bool) {
+	return nil, false
+}
+
+type value struct {
+	Params
+
+	key, val any
+}
+
+func (v value) Param(key any) (any, bool) {
+	if v.key == key {
+		return v.val, true
+	}
+
+	return v.Params.Param(key)
+}
+
+type chain []Params
+
+func (c chain) Param(key any) (any, bool) {
+	for _, p := range c {
+		val, ok := p.Param(key)
+		if ok {
+			return val, ok
+		}
+	}
+
+	return nil, false
+}

param/param_test.go

@@ -0,0 +1,49 @@
+package param_test
+
+import (
+	"testing"
+
+	"gitoa.ru/go-4devs/config/param"
+)
+
+func TestChainReplace(t *testing.T) {
+	t.Parallel()
+
+	const (
+		replaceParam = "param1"
+		replaceValue = "replace"
+	)
+
+	params1 := param.With(param.New(), replaceParam, "param1")
+	params2 := param.With(param.New(), replaceParam, replaceValue)
+
+	data, ok := param.String(param.Chain(params1, params2), replaceParam)
+	if !ok {
+		t.Errorf("param %v: not found", replaceParam)
+	}
+
+	if data != replaceValue {
+		t.Errorf("got:%v, expect:%v", data, replaceValue)
+	}
+}
+
+func TestChainExtend(t *testing.T) {
+	t.Parallel()
+
+	const (
+		extendParam = "param1"
+		extendValue = "replace"
+	)
+
+	params1 := param.With(param.New(), extendParam, extendValue)
+	params2 := param.With(param.New(), "new_value", "param2")
+
+	data1, ok := param.String(param.Chain(params1, params2), extendParam)
+	if !ok {
+		t.Errorf("param %v: not found", extendParam)
+	}
+
+	if data1 != extendValue {
+		t.Errorf("got:%v, expect:%v", data1, extendParam)
+	}
+}

processor/csv/processor.go

@@ -0,0 +1,123 @@
+package csv
+
+import (
+	"bytes"
+	"context"
+	"encoding/csv"
+	"fmt"
+
+	"gitoa.ru/go-4devs/config"
+	"gitoa.ru/go-4devs/config/param"
+	"gitoa.ru/go-4devs/config/value"
+)
+
+type pkey int
+
+const (
+	paramDelimiter pkey = iota + 1
+	paramParse
+)
+
+const defaultDelimiter = ','
+
+func WithDelimiter(in rune) param.Option {
+	return func(p param.Params) param.Params {
+		return param.With(p, paramDelimiter, in)
+	}
+}
+
+func WithInt(p param.Params) param.Params {
+	return param.With(p, paramParse, func(data []string) (config.Value, error) {
+		return value.ParseSlice(data, value.Atoi)
+	})
+}
+
+func WithInt64(p param.Params) param.Params {
+	return param.With(p, paramParse, func(data []string) (config.Value, error) {
+		return value.ParseSlice(data, value.ParseInt64)
+	})
+}
+
+func WithFloat(p param.Params) param.Params {
+	return param.With(p, paramParse, func(data []string) (config.Value, error) {
+		return value.ParseSlice(data, value.ParseFloat)
+	})
+}
+
+func WithBool(p param.Params) param.Params {
+	return param.With(p, paramParse, func(data []string) (config.Value, error) {
+		return value.ParseSlice(data, value.ParseBool)
+	})
+}
+
+func WithUint(p param.Params) param.Params {
+	return param.With(p, paramParse, func(data []string) (config.Value, error) {
+		return value.ParseSlice(data, value.ParseUint)
+	})
+}
+
+func WithUint64(p param.Params) param.Params {
+	return param.With(p, paramParse, func(data []string) (config.Value, error) {
+		return value.ParseSlice(data, value.ParseUint64)
+	})
+}
+
+func WithDuration(p param.Params) param.Params {
+	return param.With(p, paramParse, func(data []string) (config.Value, error) {
+		return value.ParseSlice(data, value.ParseDuration)
+	})
+}
+
+func WithTime(p param.Params) param.Params {
+	return param.With(p, paramParse, func(data []string) (config.Value, error) {
+		return value.ParseSlice(data, value.ParseTime)
+	})
+}
+
+func WithParse(fn func(data []string) config.Value) param.Option {
+	return func(p param.Params) param.Params {
+		return param.With(p, paramParse, fn)
+	}
+}
+
+func Csv(_ context.Context, in config.Value, opts ...param.Option) (config.Value, error) {
+	sval, serr := in.ParseString()
+	if serr != nil {
+		return in, nil //nolint:nilerr
+	}
+
+	params := param.New(opts...)
+
+	reader := csv.NewReader(bytes.NewBufferString(sval))
+	reader.Comma = getDelimiter(params)
+
+	data, rerr := reader.Read()
+	if rerr != nil {
+		return nil, fmt.Errorf("read csv:%w", rerr)
+	}
+
+	return csvValue(params, data)
+}
+
+func csvValue(params param.Params, data []string) (config.Value, error) {
+	fn, ok := params.Param(paramParse)
+	if !ok {
+		return stringsValue(data)
+	}
+
+	parse, _ := fn.(func([]string) (config.Value, error))
+
+	return parse(data)
+}
+
+func stringsValue(data []string) (config.Value, error) {
+	return value.New(data), nil
+}
+
+func getDelimiter(params param.Params) rune {
+	if name, ok := param.Rune(params, paramDelimiter); ok {
+		return name
+	}
+
+	return defaultDelimiter
+}

processor/csv/processor_test.go

@@ -0,0 +1,54 @@
+package csv_test
+
+import (
+	"context"
+	"testing"
+
+	"gitoa.ru/go-4devs/config"
+	"gitoa.ru/go-4devs/config/processor/csv"
+	"gitoa.ru/go-4devs/config/test/require"
+	"gitoa.ru/go-4devs/config/value"
+)
+
+func TestCsv(t *testing.T) {
+	t.Parallel()
+
+	ctx := context.Background()
+
+	val := value.String("test2,test3,other")
+
+	data, derr := csv.Csv(ctx, val)
+	require.NoError(t, derr)
+
+	var resString []string
+
+	require.NoError(t, data.Unmarshal(&resString))
+	require.Equal(t, []string{"test2", "test3", "other"}, resString)
+}
+
+func TestCsv_int(t *testing.T) {
+	t.Parallel()
+
+	ctx := context.Background()
+
+	val := value.String("42,0,1")
+
+	data, derr := csv.Csv(ctx, val, csv.WithInt)
+	require.NoError(t, derr)
+
+	var resInt []int
+
+	require.NoError(t, data.Unmarshal(&resInt))
+	require.Equal(t, []int{42, 0, 1}, resInt)
+}
+
+func TestCsv_invalidValue(t *testing.T) {
+	t.Parallel()
+
+	ctx := context.Background()
+	val := value.String("42,0.1,1")
+
+	data, derr := csv.Csv(ctx, val, csv.WithInt)
+	require.ErrorIs(t, derr, config.ErrInvalidValue)
+	require.Equal(t, nil, data)
+}

processor/env/processor.go

@@ -0,0 +1,27 @@
+package env
+
+import (
+	"context"
+	"fmt"
+	"os"
+
+	"gitoa.ru/go-4devs/config"
+	"gitoa.ru/go-4devs/config/param"
+	"gitoa.ru/go-4devs/config/value"
+)
+
+var _ config.ProcessFunc = Env
+
+func Env(_ context.Context, in config.Value, _ ...param.Option) (config.Value, error) {
+	key, err := in.ParseString()
+	if err != nil {
+		return in, fmt.Errorf("process[env]:%w", err)
+	}
+
+	res, ok := os.LookupEnv(key)
+	if !ok {
+		return nil, fmt.Errorf("%w", config.ErrNotFound)
+	}
+
+	return value.String(res), nil
+}

processor/json/processor.go

@@ -0,0 +1,19 @@
+package json //nolint:revive
+
+import (
+	"context"
+
+	"gitoa.ru/go-4devs/config"
+	"gitoa.ru/go-4devs/config/param"
+	"gitoa.ru/go-4devs/config/value"
+)
+
+//nolint:revive
+func Json(_ context.Context, in config.Value, _ ...param.Option) (config.Value, error) {
+	data, err := in.ParseString()
+	if err != nil {
+		return in, nil //nolint:nilerr
+	}
+
+	return value.JString(data), nil
+}

processor/json/processor_test.go

@@ -0,0 +1,48 @@
+package json_test
+
+import (
+	"context"
+	"testing"
+
+	"gitoa.ru/go-4devs/config"
+	"gitoa.ru/go-4devs/config/processor/json"
+	"gitoa.ru/go-4devs/config/test/require"
+	"gitoa.ru/go-4devs/config/value"
+)
+
+func TestJson(t *testing.T) {
+	t.Parallel()
+
+	ctx := context.Background()
+	val, err := json.Json(ctx, value.String("42"))
+	require.NoError(t, err)
+
+	var res int
+	require.NoError(t, val.Unmarshal(&res))
+	require.Equal(t, 42, res)
+
+	sval, serr := json.Json(ctx, value.String("\"test data\""))
+	require.NoError(t, serr)
+
+	var sres string
+	require.NoError(t, sval.Unmarshal(&sres))
+	require.Equal(t, "test data", sres)
+
+	slval, slerr := json.Json(ctx, value.String("[\"test\",\"test2 data\",\"test3\"]"))
+	require.NoError(t, slerr)
+
+	var slres []string
+	require.NoError(t, slval.Unmarshal(&slres))
+	require.Equal(t, []string{"test", "test2 data", "test3"}, slres)
+}
+
+func TestJson_invalidValue(t *testing.T) {
+	t.Parallel()
+
+	ctx := context.Background()
+	val, err := json.Json(ctx, value.New("42"))
+	require.NoError(t, err)
+
+	var data string
+	require.ErrorIs(t, val.Unmarshal(&data), config.ErrInvalidValue)
+}

processor/key/processor.go

@@ -0,0 +1,49 @@
+package key
+
+import (
+	"context"
+	"fmt"
+
+	"gitoa.ru/go-4devs/config"
+	"gitoa.ru/go-4devs/config/param"
+	"gitoa.ru/go-4devs/config/value"
+)
+
+type pkey int
+
+const paramKey pkey = iota
+
+func WithKey(in string) param.Option {
+	return func(p param.Params) param.Params {
+		return param.With(p, paramKey, in)
+	}
+}
+
+func Key(_ context.Context, in config.Value, opts ...param.Option) (config.Value, error) {
+	data := make(map[string]any, 0)
+	if err := in.Unmarshal(&data); err != nil {
+		return nil, fmt.Errorf("unmarshal:%w", err)
+	}
+
+	key, ok := getKey(opts...)
+	if !ok {
+		return nil, fmt.Errorf("key is %w", config.ErrRequired)
+	}
+
+	val, vok := data[key]
+	if !vok {
+		return nil, fmt.Errorf("value by key[%v]: %w", key, config.ErrNotFound)
+	}
+
+	return value.New(val), nil
+}
+
+func getKey(opts ...param.Option) (string, bool) {
+	params := param.New(opts...)
+
+	if name, ok := param.String(params, paramKey); ok {
+		return name, ok
+	}
+
+	return "", false
+}

processor/key/processor_test.go

@@ -0,0 +1,58 @@
+package key_test
+
+import (
+	"context"
+	"encoding/json"
+	"testing"
+
+	"gitoa.ru/go-4devs/config"
+	"gitoa.ru/go-4devs/config/processor/key"
+	"gitoa.ru/go-4devs/config/test/require"
+	"gitoa.ru/go-4devs/config/value"
+)
+
+func TestKey(t *testing.T) {
+	t.Parallel()
+
+	ctx := context.Background()
+
+	res, rerr := key.Key(ctx, keyData(t), key.WithKey("key"))
+	require.NoError(t, rerr)
+
+	require.Equal(t, "value", res.String())
+}
+
+func TestKey_required(t *testing.T) {
+	t.Parallel()
+
+	ctx := context.Background()
+
+	res, rerr := key.Key(ctx, keyData(t))
+	require.ErrorIs(t, rerr, config.ErrRequired)
+
+	require.Equal(t, res, nil)
+}
+
+func TestKey_notFound(t *testing.T) {
+	t.Parallel()
+
+	ctx := context.Background()
+
+	res, rerr := key.Key(ctx, keyData(t), key.WithKey("wrong"))
+	require.ErrorIs(t, rerr, config.ErrNotFound)
+
+	require.Equal(t, res, nil)
+}
+
+func keyData(t *testing.T) config.Value {
+	t.Helper()
+
+	data := map[string]string{
+		"key": "value",
+	}
+
+	jdata, err := json.Marshal(data)
+	require.NoError(t, err)
+
+	return value.JBytes(jdata)
+}

provider.go

@@ -1,14 +1,15 @@
 package config
 
-import "context"
+import (
+	"context"
+	"io"
+
+	"gitoa.ru/go-4devs/config/param"
+)
 
 type Provider interface {
 	Value(ctx context.Context, path ...string) (Value, error)
-}
-
-type NamedProvider interface {
 	Name() string
-	Provider
 }
 
 type WatchCallback func(ctx context.Context, oldVar, newVar Value) error
@@ -17,4 +18,61 @@ type WatchProvider interface {
 	Watch(ctx context.Context, callback WatchCallback, path ...string) error
 }
 
-type Factory func(ctx context.Context, cfg Provider) (Provider, error)
+type Factory interface {
+	Name() string
+	Create(ctx context.Context, prov Provider) (Provider, error)
+}
+
+type Option interface {
+	Name() string
+	Param(key any) (any, bool)
+}
+
+type Group interface {
+	Option
+	Options
+}
+
+type Options interface {
+	Options() []Option
+	param.Params
+}
+
+type BindProvider interface {
+	Provider
+
+	Bind(ctx context.Context, data Variables) error
+}
+
+type DunpProvider interface {
+	Provider
+
+	DumpRefernce(ctx context.Context, w io.Writer, opts Options) error
+}
+
+type Providers interface {
+	Provider
+
+	Provider(name string) (Provider, error)
+	Names() []string
+}
+
+type Variables interface {
+	ByName(name ...string) (Variable, error)
+	ByParam(filter param.Has) (Variable, error)
+	Variables() []Variable
+}
+
+type Definition interface {
+	Add(opts ...Option)
+}
+
+type ProcessFunc func(ctx context.Context, in Value, opts ...param.Option) (Value, error)
+
+func (o ProcessFunc) Process(ctx context.Context, in Value, opts ...param.Option) (Value, error) {
+	return o(ctx, in, opts...)
+}
+
+type Processor interface {
+	Process(ctx context.Context, in Value, opts ...param.Option) (Value, error)
+}

provider/arg/dump.go

@@ -0,0 +1,419 @@
+package arg
+
+import (
+	"bytes"
+	"encoding"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"sort"
+	"strings"
+	"time"
+
+	"gitoa.ru/go-4devs/config"
+	"gitoa.ru/go-4devs/config/definition/option"
+	"gitoa.ru/go-4devs/config/param"
+)
+
+const (
+	defaultSpace = 2
+)
+
+func ResolveStyle(params param.Params) ViewStyle {
+	var vs ViewStyle
+
+	data, ok := params.Param(paramDumpReferenceView)
+	if ok {
+		vs, _ = data.(ViewStyle)
+	}
+
+	return vs
+}
+
+func WithStyle(comment, info Style) param.Option {
+	return func(p param.Params) param.Params {
+		return param.With(p, paramDumpReferenceView, ViewStyle{
+			Comment: comment,
+			Info:    info,
+			MLen:    0,
+		})
+	}
+}
+
+type ViewStyle struct {
+	Comment Style
+	Info    Style
+	MLen    int
+}
+
+func (v ViewStyle) ILen() int {
+	return v.Info.Len() + v.MLen
+}
+
+type Style struct {
+	Start string
+	End   string
+}
+
+func (s Style) Len() int {
+	return len(s.End) + len(s.Start)
+}
+
+func NewDump() Dump {
+	return Dump{
+		sep:   dash,
+		space: defaultSpace,
+	}
+}
+
+type Dump struct {
+	sep   string
+	space int
+}
+
+func (d Dump) Reference(w io.Writer, opt config.Options) error {
+	views := NewViews(opt, nil)
+	style := ResolveStyle(opt)
+	style.MLen = d.keyMaxLen(views...)
+
+	if args := views.Arguments(); len(args) > 0 {
+		if aerr := d.writeArguments(w, style, args...); aerr != nil {
+			return fmt.Errorf("write arguments:%w", aerr)
+		}
+	}
+
+	if opts := views.Options(); len(opts) > 0 {
+		if oerr := d.writeOptions(w, style, opts...); oerr != nil {
+			return fmt.Errorf("write option:%w", oerr)
+		}
+	}
+
+	return nil
+}
+
+//nolint:mnd
+func (d Dump) keyMaxLen(views ...View) int {
+	var maxLen int
+
+	for _, vi := range views {
+		vlen := len(vi.Name(d.sep)) + d.space
+
+		if !vi.IsArgument() {
+			if !vi.IsBool() {
+				vlen = vlen*2 + 1
+			}
+
+			if def := vi.Default(); def != "" {
+				vlen += d.space
+			}
+
+			vlen += 4 + d.space
+		}
+
+		if vlen > maxLen {
+			maxLen = vlen
+		}
+	}
+
+	return maxLen
+}
+
+func (d Dump) writeArguments(w io.Writer, style ViewStyle, args ...View) error {
+	_, err := fmt.Fprintf(w, "\n%sArguments:%s\n",
+		style.Comment.Start,
+		style.Comment.End,
+	)
+
+	for _, arg := range args {
+		alen, ierr := fmt.Fprintf(w, "%s%s%s%s",
+			strings.Repeat(" ", d.space),
+			style.Info.Start,
+			arg.Name(d.sep),
+			style.Info.End,
+		)
+		if ierr != nil {
+			err = errors.Join(err, ierr)
+		}
+
+		_, ierr = fmt.Fprint(w, strings.Repeat(" ", style.ILen()+d.space-alen))
+		if ierr != nil {
+			err = errors.Join(err, ierr)
+		}
+
+		_, ierr = fmt.Fprint(w, arg.Description())
+		if ierr != nil {
+			err = errors.Join(err, ierr)
+		}
+
+		if def := arg.Default(); def != "" {
+			ierr := d.writeDefault(w, style, def)
+			if ierr != nil {
+				err = errors.Join(err, ierr)
+			}
+		}
+
+		_, ierr = fmt.Fprint(w, "\n")
+		if ierr != nil {
+			err = errors.Join(err, ierr)
+		}
+	}
+
+	if err != nil {
+		return fmt.Errorf("%w", err)
+	}
+
+	return nil
+}
+
+//nolint:gocognit,gocyclo,cyclop
+func (d Dump) writeOptions(w io.Writer, style ViewStyle, opts ...View) error {
+	_, err := fmt.Fprintf(w, "\n%sOptions:%s\n",
+		style.Comment.Start,
+		style.Comment.End,
+	)
+
+	for _, opt := range opts {
+		if opt.IsHidden() {
+			continue
+		}
+
+		var op bytes.Buffer
+
+		_, oerr := fmt.Fprintf(&op, "%s%s", strings.Repeat(" ", d.space), style.Info.Start)
+		if oerr != nil {
+			err = errors.Join(err, oerr)
+		}
+
+		if short := opt.Short(); short != "" {
+			op.WriteString("-")
+			op.WriteString(short)
+			op.WriteString(", ")
+		} else {
+			op.WriteString("    ")
+		}
+
+		op.WriteString("--")
+		op.WriteString(opt.Name(d.sep))
+
+		if !opt.IsBool() {
+			if !opt.IsRequired() {
+				op.WriteString("[")
+			}
+
+			op.WriteString("=")
+			op.WriteString(strings.ToUpper(opt.Name(d.sep)))
+
+			if !opt.IsRequired() {
+				op.WriteString("]")
+			}
+		}
+
+		_, oerr = fmt.Fprintf(&op, "%s", style.Info.End)
+		if oerr != nil {
+			err = errors.Join(err, oerr)
+		}
+
+		olen, oerr := w.Write(op.Bytes())
+		if oerr != nil {
+			err = errors.Join(err, oerr)
+		}
+
+		_, oerr = fmt.Fprintf(w, "%s%s",
+			strings.Repeat(" ", style.ILen()+d.space-olen),
+			opt.Description(),
+		)
+		if oerr != nil {
+			err = errors.Join(err, oerr)
+		}
+
+		if def := opt.Default(); def != "" {
+			oerr = d.writeDefault(w, style, def)
+			if oerr != nil {
+				err = errors.Join(err, oerr)
+			}
+		}
+
+		if opt.IsSlice() {
+			_, oerr = fmt.Fprintf(w, "%s  (multiple values allowed)%s", style.Comment.Start, style.Comment.End)
+			if oerr != nil {
+				err = errors.Join(err, oerr)
+			}
+		}
+
+		_, oerr = fmt.Fprint(w, "\n")
+		if oerr != nil {
+			err = errors.Join(err, oerr)
+		}
+	}
+
+	if err != nil {
+		return fmt.Errorf("write options:%w", err)
+	}
+
+	return nil
+}
+
+func (d Dump) writeDefault(w io.Writer, style ViewStyle, data string) error {
+	_, err := fmt.Fprintf(w, " %s[default:%s]%s",
+		style.Comment.Start,
+		data,
+		style.Comment.End,
+	)
+	if err != nil {
+		return fmt.Errorf("default:%w", err)
+	}
+
+	return nil
+}
+
+func NewViews(opts config.Options, parent *View) Views {
+	views := make(Views, 0, len(opts.Options()))
+	for _, opt := range opts.Options() {
+		views = append(views, newViews(opt, parent)...)
+	}
+
+	return views
+}
+
+func newViews(opt config.Option, parent *View) []View {
+	view := NewView(opt, parent)
+	switch one := opt.(type) {
+	case config.Group:
+		return NewViews(one, &view)
+	default:
+		return []View{view}
+	}
+}
+
+type Views []View
+
+func (v Views) Arguments() []View {
+	args := make([]View, 0, len(v))
+
+	for _, view := range v {
+		if view.IsArgument() {
+			args = append(args, view)
+		}
+	}
+
+	sort.Slice(args, func(i, j int) bool {
+		return args[i].Pos() < args[j].Pos()
+	})
+
+	return args
+}
+
+func (v Views) Options() []View {
+	opts := make([]View, 0, len(v))
+
+	for _, view := range v {
+		if !view.IsArgument() {
+			opts = append(opts, view)
+		}
+	}
+
+	sort.Slice(opts, func(i, j int) bool {
+		return opts[i].Pos() < opts[j].Pos()
+	})
+
+	return opts
+}
+
+func NewView(params config.Option, parent *View) View {
+	pos, ok := ParamArgument(params)
+
+	keys := make([]string, 0)
+	if parent != nil {
+		keys = append(keys, parent.Keys()...)
+	}
+
+	if !ok {
+		pos = param.Position(params)
+	}
+
+	if name := params.Name(); name != "" {
+		keys = append(keys, name)
+	}
+
+	return View{
+		pos:        pos,
+		isArgument: ok,
+		keys:       keys,
+		parent:     parent,
+		Params:     params,
+	}
+}
+
+type View struct {
+	param.Params
+
+	keys       []string
+	pos        uint64
+	isArgument bool
+	parent     *View
+}
+
+func (v View) Name(delimiter string) string {
+	return strings.Join(v.keys, delimiter)
+}
+
+func (v View) IsArgument() bool {
+	return v.isArgument
+}
+
+func (v View) Keys() []string {
+	return v.keys
+}
+
+func (v View) Pos() uint64 {
+	return v.pos
+}
+
+func (v View) Default() string {
+	data, ok := param.Default(v.Params)
+	if !ok {
+		return ""
+	}
+
+	switch dt := data.(type) {
+	case time.Time:
+		return dt.Format(time.RFC3339)
+	case encoding.TextMarshaler:
+		if res, err := dt.MarshalText(); err == nil {
+			return string(res)
+		}
+	case json.Marshaler:
+		if res, err := dt.MarshalJSON(); err == nil {
+			return string(res)
+		}
+	}
+
+	return fmt.Sprintf("%v", data)
+}
+
+func (v View) Description() string {
+	return param.Description(v.Params)
+}
+
+func (v View) IsHidden() bool {
+	return option.IsHidden(v.Params)
+}
+
+func (v View) Short() string {
+	short, _ := option.ParamShort(v.Params)
+
+	return short
+}
+
+func (v View) IsRequired() bool {
+	return option.IsHidden(v.Params)
+}
+
+func (v View) IsBool() bool {
+	return option.IsBool(v.Params)
+}
+
+func (v View) IsSlice() bool {
+	return option.IsSlice(v.Params)
+}

provider/arg/dump_test.go

@@ -0,0 +1,35 @@
+package arg_test
+
+import (
+	"bytes"
+	"testing"
+
+	"gitoa.ru/go-4devs/config/provider/arg"
+	"gitoa.ru/go-4devs/config/test/require"
+)
+
+func TestDumpReference(t *testing.T) {
+	t.Parallel()
+
+	//nolint:dupword
+	const expect = `
+Arguments:
+  config                                           config [default:config.hcl]
+  user-name                                        username
+
+Options:
+  -l, --listen[=LISTEN]                            listen [default:8080]
+  -p, --user-password[=USER-PASSWORD]              user pass
+  -u, --url[=URL]                                  url  (multiple values allowed)
+  -t, --timeout[=TIMEOUT]                          timeout  (multiple values allowed)
+      --start-at[=START-AT]                        start at [default:2010-01-02T15:04:05Z]
+      --end-after[=END-AFTER]                      after  (multiple values allowed)
+      --end-{service}-after[=END-{SERVICE}-AFTER]  after
+`
+
+	dump := arg.NewDump()
+
+	var buff bytes.Buffer
+	require.NoError(t, dump.Reference(&buff, testOptions(t)))
+	require.Equal(t, expect, buff.String())
+}

provider/arg/helper_test.go

@@ -0,0 +1,38 @@
+package arg_test
+
+import (
+	"testing"
+
+	"gitoa.ru/go-4devs/config"
+	"gitoa.ru/go-4devs/config/definition"
+	"gitoa.ru/go-4devs/config/definition/group"
+	"gitoa.ru/go-4devs/config/definition/option"
+	"gitoa.ru/go-4devs/config/definition/proto"
+	"gitoa.ru/go-4devs/config/provider/arg"
+	"gitoa.ru/go-4devs/config/test"
+)
+
+func testOptions(t *testing.T) config.Options {
+	t.Helper()
+
+	def := definition.New()
+	def.Add(
+		option.Int("listen", "listen", option.Short('l'), option.Default(8080)),
+		option.String("config", "config", arg.Argument, option.Default("config.hcl")),
+		group.New("user", "configure user",
+			option.String("name", "username", arg.Argument),
+			option.String("password", "user pass", option.Short('p')),
+		),
+		option.String("url", "url", option.Short('u'), option.Slice),
+		option.Duration("timeout", "timeout", option.Short('t'), option.Slice),
+		option.Time("start-at", "start at", option.Default(test.Time("2010-01-02T15:04:05Z"))),
+		group.New("end", "end at",
+			option.Time("after", "after", option.Slice),
+			proto.New("service", "service after",
+				option.Time("after", "after"),
+			),
+		),
+	)
+
+	return def
+}

provider/arg/option.go

@@ -0,0 +1,59 @@
+package arg
+
+import (
+	"gitoa.ru/go-4devs/config/definition/option"
+	"gitoa.ru/go-4devs/config/param"
+	"gitoa.ru/go-4devs/config/value"
+)
+
+func Default(in any) param.Option {
+	return option.Default(value.New(in))
+}
+
+func Required(v param.Params) {
+	option.Required(v)
+}
+
+func Slice(v param.Params) {
+	option.Slice(v)
+}
+
+func String(name, description string, opts ...param.Option) option.Option {
+	return option.String(name, description, append(opts, Argument)...)
+}
+
+func Bool(name, description string, opts ...param.Option) option.Option {
+	return option.Bool(name, description, append(opts, Argument)...)
+}
+
+func Duration(name, description string, opts ...param.Option) option.Option {
+	return option.Duration(name, description, append(opts, Argument)...)
+}
+
+func Float64(name, description string, opts ...param.Option) option.Option {
+	return option.Float64(name, description, append(opts, Argument)...)
+}
+
+func Int(name, description string, opts ...param.Option) option.Option {
+	return option.Int(name, description, append(opts, Argument)...)
+}
+
+func Int64(name, description string, opts ...param.Option) option.Option {
+	return option.Int64(name, description, append(opts, Argument)...)
+}
+
+func Time(name, description string, opts ...param.Option) option.Option {
+	return option.Time(name, description, append(opts, Argument)...)
+}
+
+func Uint(name, description string, opts ...param.Option) option.Option {
+	return option.Uint(name, description, append(opts, Argument)...)
+}
+
+func Uint64(name, descriontion string, opts ...param.Option) option.Option {
+	return option.Uint64(name, descriontion, append(opts, Argument)...)
+}
+
+func Err(err error, key ...string) option.Error {
+	return option.Err(err, key)
+}

provider/arg/param.go

@@ -0,0 +1,39 @@
+package arg
+
+import (
+	"sync/atomic"
+
+	"gitoa.ru/go-4devs/config/param"
+)
+
+type keyParam int
+
+const (
+	paramArgument keyParam = iota + 1
+	paramDumpReferenceView
+)
+
+//nolint:gochecknoglobals
+var argNum uint64
+
+func Argument(v param.Params) param.Params {
+	return param.With(v, paramArgument, atomic.AddUint64(&argNum, 1)-1)
+}
+
+func ParamArgument(fn param.Params) (uint64, bool) {
+	return param.Uint64(paramArgument, fn)
+}
+
+func PosArgument(in uint64) param.Has {
+	return func(p param.Params) bool {
+		idx, ok := ParamArgument(p)
+
+		return ok && idx == in
+	}
+}
+
+func HasArgument(fn param.Params) bool {
+	_, ok := ParamArgument(fn)
+
+	return ok
+}

provider/arg/provider.go

@@ -2,50 +2,238 @@ package arg
 
 import (
 	"context"
-	"encoding/json"
 	"fmt"
+	"io"
 	"os"
 	"strings"
 
 	"gitoa.ru/go-4devs/config"
-	"gitoa.ru/go-4devs/config/value"
+	"gitoa.ru/go-4devs/config/definition/option"
+	"gitoa.ru/go-4devs/config/key"
+	"gitoa.ru/go-4devs/config/param"
+	"gitoa.ru/go-4devs/config/provider/memory"
 )
 
-const Name = "arg"
+const (
+	doubleDash           = `--`
+	defaultLenLognOption = 2
+	dash                 = `-`
+)
 
-var _ config.Provider = (*Provider)(nil)
+// Deprecated: use WithArgs.
+func WithSkip(skip int) func(*Argv) {
+	return func(ar *Argv) {
+		res := 2
 
-type Option func(*Provider)
+		switch {
+		case skip > 0 && len(os.Args) > skip:
+			res = skip
+		case skip > 0:
+			res = len(os.Args)
+		case len(os.Args) == 1:
+			res = 1
+		case len(os.Args) > 1 && os.Args[1][0] == '-':
+			res = 1
+		}
 
-func WithKeyFactory(factory func(s ...string) string) Option {
-	return func(p *Provider) { p.key = factory }
+		ar.args = os.Args[res:]
+	}
 }
 
-func New(opts ...Option) *Provider {
-	prov := Provider{
-		key: func(s ...string) string {
-			return strings.Join(s, "-")
-		},
-		args: make(map[string][]string, len(os.Args[1:])),
-		name: Name,
+func WithArgs(args []string) func(*Argv) {
+	return func(a *Argv) {
+		a.args = args
+	}
+}
+
+func New(opts ...func(*Argv)) *Argv {
+	arg := &Argv{
+		args: os.Args[1:],
+		pos:  0,
+		Map:  memory.Map{},
 	}
 
 	for _, opt := range opts {
-		opt(&prov)
+		opt(arg)
 	}
 
-	return &prov
+	return arg
 }
 
-type Provider struct {
-	args map[string][]string
-	key  func(...string) string
-	name string
+type Argv struct {
+	memory.Map
+
+	args []string
+	pos  uint64
 }
 
-// nolint: cyclop
-// return name, value, error.
-func (p *Provider) parseOne(arg string) (string, string, error) {
+func (i *Argv) Value(ctx context.Context, key ...string) (config.Value, error) {
+	if err := i.parse(); err != nil {
+		return nil, fmt.Errorf("parse:%w", err)
+	}
+
+	data, err := i.Map.Value(ctx, key...)
+	if err != nil {
+		return nil, fmt.Errorf("map: %w", err)
+	}
+
+	return data, nil
+}
+
+func (i *Argv) Bind(ctx context.Context, def config.Variables) error {
+	options := true
+
+	for len(i.args) > 0 {
+		var err error
+
+		arg := i.args[0]
+		i.args = i.args[1:]
+
+		switch {
+		case options && arg == doubleDash:
+			options = false
+		case options && len(arg) > 2 && arg[0:2] == doubleDash:
+			err = i.parseLongOption(arg[2:], def)
+		case options && arg[0:1] == "-":
+			if len(arg) == 1 {
+				return fmt.Errorf("%w: option name required given '-'", config.ErrInvalidName)
+			}
+
+			err = i.parseShortOption(arg[1:], def)
+		default:
+			err = i.parseArgument(arg, def)
+		}
+
+		if err != nil {
+			return fmt.Errorf("arg bind:%w", err)
+		}
+	}
+
+	if err := i.Map.Bind(ctx, def); err != nil {
+		return fmt.Errorf("arg map:%w", err)
+	}
+
+	return nil
+}
+
+func (i *Argv) DumpRefernce(_ context.Context, w io.Writer, opt config.Options) error {
+	return NewDump().Reference(w, opt)
+}
+
+func (i *Argv) parseLongOption(arg string, def config.Variables) error {
+	var value *string
+
+	name := arg
+
+	if strings.Contains(arg, "=") {
+		vals := strings.SplitN(arg, "=", defaultLenLognOption)
+		name = vals[0]
+		value = &vals[1]
+	}
+
+	opt, err := def.ByName(key.ByPath(name, dash)...)
+	if err != nil {
+		return Err(err, name)
+	}
+
+	return i.appendOption(value, opt)
+}
+
+func (i *Argv) appendOption(data *string, opt config.Variable) error {
+	if i.HasOption(opt.Key()...) && !option.IsSlice(opt) {
+		return fmt.Errorf("%w: got: array, expect: %T", config.ErrUnexpectedType, param.Type(opt))
+	}
+
+	var val string
+
+	switch {
+	case data != nil:
+		val = *data
+	case option.IsBool(opt):
+		val = "true"
+	case len(i.args) > 0 && len(i.args[0]) > 0 && i.args[0][0:1] != "-":
+		val = i.args[0]
+		i.args = i.args[1:]
+	default:
+		return Err(config.ErrRequired, opt.Key()...)
+	}
+
+	err := i.AppendOption(val, opt.Key()...)
+	if err != nil {
+		return Err(err, opt.Key()...)
+	}
+
+	return nil
+}
+
+func (i *Argv) parseShortOption(arg string, def config.Variables) error {
+	name := arg
+
+	var value string
+
+	if len(name) > 1 {
+		name, value = arg[0:1], strings.TrimSpace(arg[1:])
+	}
+
+	opt, err := def.ByParam(option.HasShort(name))
+	if err != nil {
+		return fmt.Errorf("%w", err)
+	}
+
+	if option.IsBool(opt) && value != "" {
+		err := i.parseShortOption(value, def)
+		if err != nil {
+			return err
+		}
+
+		value = ""
+	}
+
+	if value == "" {
+		return i.appendOption(nil, opt)
+	}
+
+	return i.appendOption(&value, opt)
+}
+
+func (i *Argv) parseArgument(arg string, def config.Variables) error {
+	opt, err := def.ByParam(PosArgument(i.pos))
+	if err != nil {
+		return fmt.Errorf("%w", err)
+	}
+
+	i.pos++
+
+	if err := i.AppendOption(arg, opt.Key()...); err != nil {
+		return Err(err, opt.Key()...)
+	}
+
+	return nil
+}
+
+func (i *Argv) parse() error {
+	if i.Len() > 0 {
+		return nil
+	}
+
+	for _, arg := range i.args {
+		name, value, err := i.parseOne(arg)
+		if err != nil {
+			return err
+		}
+
+		if name != "" {
+			if err := i.AppendOption(value, name); err != nil {
+				return fmt.Errorf("append %v: %w", name, err)
+			}
+		}
+	}
+
+	return nil
+}
+
+// parseOne return name, value, error.
+func (i *Argv) parseOne(arg string) (string, string, error) {
 	if arg[0] != '-' {
 		return "", "", nil
 	}
@@ -82,55 +270,3 @@ func (p *Provider) parseOne(arg string) (string, string, error) {
 
 	return name, val, nil
 }
-
-func (p *Provider) parse() error {
-	if len(p.args) > 0 {
-		return nil
-	}
-
-	for _, arg := range os.Args[1:] {
-		name, value, err := p.parseOne(arg)
-		if err != nil {
-			return err
-		}
-
-		if name != "" {
-			p.args[name] = append(p.args[name], value)
-		}
-	}
-
-	return nil
-}
-
-func (p *Provider) Name() string {
-	return p.name
-}
-
-func (p *Provider) Value(_ context.Context, path ...string) (config.Value, error) {
-	if err := p.parse(); err != nil {
-		return nil, err
-	}
-
-	name := p.key(path...)
-	if val, ok := p.args[name]; ok {
-		switch {
-		case len(val) == 1:
-			return value.JString(val[0]), nil
-		default:
-			data, jerr := json.Marshal(val)
-			if jerr != nil {
-				return nil, fmt.Errorf("failed load data:%w", jerr)
-			}
-
-			return value.Decode(func(v interface{}) error {
-				if err := json.Unmarshal(data, v); err != nil {
-					return fmt.Errorf("unmarshal:%w", err)
-				}
-
-				return nil
-			}), nil
-		}
-	}
-
-	return nil, fmt.Errorf("%s:%w", p.Name(), config.ErrValueNotFound)
-}

provider/arg/provider_test.go

@@ -1,27 +1,22 @@
 package arg_test
 
 import (
+	"context"
 	"fmt"
-	"os"
 	"strings"
 	"testing"
 	"time"
 
+	"gitoa.ru/go-4devs/config"
 	"gitoa.ru/go-4devs/config/provider/arg"
 	"gitoa.ru/go-4devs/config/test"
+	"gitoa.ru/go-4devs/config/test/require"
 )
 
 func TestProvider(t *testing.T) {
 	t.Parallel()
 
-	args := os.Args
-
-	defer func() {
-		os.Args = args
-	}()
-
-	os.Args = []string{
-		"main.go",
+	args := []string{
 		"--listen=8080",
 		"--config=config.hcl",
 		"--url=http://4devs.io",
@@ -44,11 +39,50 @@ func TestProvider(t *testing.T) {
 		}, &[]time.Time{}, "end-after"),
 	}
 
-	prov := arg.New()
+	prov := arg.New(arg.WithArgs(args))
 
 	test.Run(t, prov, read)
 }
 
+func TestProviderBind(t *testing.T) {
+	t.Parallel()
+
+	args := []string{
+		"-l 8080",
+		"--config=config.hcl",
+		"-u http://4devs.io",
+		"--url=https://4devs.io",
+		"-t 1m",
+		"--timeout=1h",
+		"--start-at=2010-01-02T15:04:05Z",
+		"--end-after=2009-01-02T15:04:05Z",
+		"--end-after=2008-01-02T15:04:05+03:00",
+	}
+
+	read := []test.Read{
+		test.NewRead(8080, "listen"),
+		test.NewRead(test.Time("2010-01-02T15:04:05Z"), "start-at"),
+		test.NewReadUnmarshal(&[]string{"http://4devs.io", "https://4devs.io"}, &[]string{}, "url"),
+		test.NewReadUnmarshal(&[]Duration{{time.Minute}, {time.Hour}}, &[]Duration{}, "timeout"),
+		test.NewReadUnmarshal(&[]time.Time{
+			test.Time("2009-01-02T15:04:05Z"),
+			test.Time("2008-01-02T15:04:05+03:00"),
+		}, &[]time.Time{}, "end", "after"),
+	}
+
+	ctx := context.Background()
+	prov := arg.New(arg.WithArgs(args))
+	require.NoError(t, prov.Bind(ctx, testVariables(t)))
+
+	test.Run(t, prov, read)
+}
+
+func testVariables(t *testing.T) config.Variables {
+	t.Helper()
+
+	return config.NewVars(testOptions(t).Options()...)
+}
+
 type Duration struct {
 	time.Duration
 }
@@ -65,5 +99,5 @@ func (d *Duration) UnmarshalJSON(in []byte) error {
 }
 
 func (d *Duration) MarshalJSON() ([]byte, error) {
-	return []byte(fmt.Sprintf("%q", d)), nil
+	return fmt.Appendf(nil, "%q", d), nil
 }

provider/chain/chain.go

@@ -0,0 +1,83 @@
+package chain
+
+import (
+	"context"
+	"fmt"
+
+	"gitoa.ru/go-4devs/config"
+)
+
+const Name = "chain"
+
+type Providers interface {
+	config.BindProvider
+	config.Providers
+}
+
+func New(c ...config.Provider) Providers {
+	return chain(c)
+}
+
+type chain []config.Provider
+
+func (c chain) Value(ctx context.Context, name ...string) (config.Value, error) {
+	for _, in := range c {
+		if val, err := in.Value(ctx, name...); err == nil {
+			return val, nil
+		}
+	}
+
+	return nil, fmt.Errorf("%w", config.ErrNotFound)
+}
+
+func (c chain) Bind(ctx context.Context, def config.Variables) error {
+	for _, input := range c {
+		if prov, ok := input.(config.BindProvider); ok {
+			if err := prov.Bind(ctx, def); err != nil {
+				return fmt.Errorf("%T:%w", input, err)
+			}
+		}
+	}
+
+	return nil
+}
+
+func (c chain) Name() string {
+	return Name
+}
+
+func (c chain) Provider(name string) (config.Provider, error) {
+	if c.Name() == name {
+		return c, nil
+	}
+
+	for _, prov := range c {
+		if prov.Name() == name {
+			return prov, nil
+		}
+
+		cprov, ok := prov.(config.Providers)
+		if !ok {
+			continue
+		}
+
+		if in, err := cprov.Provider(name); err == nil {
+			return in, nil
+		}
+	}
+
+	return nil, fmt.Errorf("prov[%v]:%w", c.Name(), config.ErrNotFound)
+}
+
+func (c chain) Names() []string {
+	names := make([]string, 0, len(c))
+	for _, prov := range c {
+		names = append(names, prov.Name())
+
+		if cprov, ok := prov.(config.Providers); ok {
+			names = append(names, cprov.Names()...)
+		}
+	}
+
+	return names
+}

provider/dasel/go.mod

@@ -0,0 +1,21 @@
+module gitoa.ru/go-4devs/config/provider/dasel
+
+go 1.25.5
+
+require (
+	github.com/tomwright/dasel/v3 v3.2.0
+	gitoa.ru/go-4devs/config v0.0.6
+)
+
+require (
+	github.com/agext/levenshtein v1.2.1 // indirect
+	github.com/apparentlymart/go-textseg/v15 v15.0.0 // indirect
+	github.com/google/go-cmp v0.7.0 // indirect
+	github.com/hashicorp/hcl/v2 v2.24.0 // indirect
+	github.com/mitchellh/go-wordwrap v1.0.1 // indirect
+	github.com/zclconf/go-cty v1.17.0 // indirect
+	golang.org/x/mod v0.26.0 // indirect
+	golang.org/x/sync v0.16.0 // indirect
+	golang.org/x/text v0.28.0 // indirect
+	golang.org/x/tools v0.35.0 // indirect
+)

provider/dasel/go.sum

@@ -0,0 +1,30 @@
+github.com/agext/levenshtein v1.2.1 h1:QmvMAjj2aEICytGiWzmxoE0x2KZvE0fvmqMOfy2tjT8=
+github.com/agext/levenshtein v1.2.1/go.mod h1:JEDfjyjHDjOF/1e4FlBE/PkbqA9OfWu2ki2W0IB5558=
+github.com/apparentlymart/go-textseg/v15 v15.0.0 h1:uYvfpb3DyLSCGWnctWKGj857c6ew1u1fNQOlOtuGxQY=
+github.com/apparentlymart/go-textseg/v15 v15.0.0/go.mod h1:K8XmNZdhEBkdlyDdvbmmsvpAG721bKi0joRfFdHIWJ4=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/go-test/deep v1.0.3 h1:ZrJSEWsXzPOxaZnFteGEfooLba+ju3FYIbOrS+rQd68=
+github.com/go-test/deep v1.0.3/go.mod h1:wGDj63lr65AM2AQyKZd/NYHGb0R+1RLqB8NKt3aSFNA=
+github.com/google/go-cmp v0.7.0 h1:wk8382ETsv4JYUZwIsn6YpYiWiBsYLSJiTsyBybVuN8=
+github.com/google/go-cmp v0.7.0/go.mod h1:pXiqmnSA92OHEEa9HXL2W4E7lf9JzCmGVUdgjX3N/iU=
+github.com/hashicorp/hcl/v2 v2.24.0 h1:2QJdZ454DSsYGoaE6QheQZjtKZSUs9Nh2izTWiwQxvE=
+github.com/hashicorp/hcl/v2 v2.24.0/go.mod h1:oGoO1FIQYfn/AgyOhlg9qLC6/nOJPX3qGbkZpYAcqfM=
+github.com/mitchellh/go-wordwrap v1.0.1 h1:TLuKupo69TCn6TQSyGxwI1EblZZEsQ0vMlAFQflz0v0=
+github.com/mitchellh/go-wordwrap v1.0.1/go.mod h1:R62XHJLzvMFRBbcrT7m7WgmE1eOyTSsCt+hzestvNj0=
+github.com/tomwright/dasel/v3 v3.2.0 h1:wyF2A4jVADx10E0kjbzPTiaF26D0OkK2OPuQRPJRDCo=
+github.com/tomwright/dasel/v3 v3.2.0/go.mod h1:XyAl6LidZuWOISIeUmKlCqJDz4IWEDp83epNngZgOQA=
+github.com/zclconf/go-cty v1.17.0 h1:seZvECve6XX4tmnvRzWtJNHdscMtYEx5R7bnnVyd/d0=
+github.com/zclconf/go-cty v1.17.0/go.mod h1:wqFzcImaLTI6A5HfsRwB0nj5n0MRZFwmey8YoFPPs3U=
+github.com/zclconf/go-cty-debug v0.0.0-20240509010212-0d6042c53940 h1:4r45xpDWB6ZMSMNJFMOjqrGHynW3DIBuR2H9j0ug+Mo=
+github.com/zclconf/go-cty-debug v0.0.0-20240509010212-0d6042c53940/go.mod h1:CmBdvvj3nqzfzJ6nTCIwDTPZ56aVGvDrmztiO5g3qrM=
+gitoa.ru/go-4devs/config v0.0.6 h1:BbOH2KHBRMWtSwcFyHKzMXzxYbJpSwZpA8LGnnzBwk8=
+gitoa.ru/go-4devs/config v0.0.6/go.mod h1:UINWnObZA0nLiJro+TtavUBBvN0cSt17aRHOk20pP74=
+golang.org/x/mod v0.26.0 h1:EGMPT//Ezu+ylkCijjPc+f4Aih7sZvaAr+O3EHBxvZg=
+golang.org/x/mod v0.26.0/go.mod h1:/j6NAhSk8iQ723BGAUyoAcn7SlD7s15Dp9Nd/SfeaFQ=
+golang.org/x/sync v0.16.0 h1:ycBJEhp9p4vXvUZNszeOq0kGTPghopOL8q0fq3vstxw=
+golang.org/x/sync v0.16.0/go.mod h1:1dzgHSNfp02xaA81J2MS99Qcpr2w7fw1gpm99rleRqA=
+golang.org/x/text v0.28.0 h1:rhazDwis8INMIwQ4tpjLDzUhx6RlXqZNPEM0huQojng=
+golang.org/x/text v0.28.0/go.mod h1:U8nCwOR8jO/marOQ0QbDiOngZVEBB7MAiitBuMjXiNU=
+golang.org/x/tools v0.35.0 h1:mBffYraMEf7aa0sB+NuKnuCy8qI/9Bughn8dC2Gu5r0=
+golang.org/x/tools v0.35.0/go.mod h1:NKdj5HkL/73byiZSJjqJgKn3ep7KjFkBOkR/Hps3VPw=

provider/dasel/hcl/fixture/config.hcl

@@ -0,0 +1,18 @@
+app {
+  name {
+    var = [
+      "name"
+    ]
+
+    title = "config title"
+    timeout = "1m"
+    success = true
+  }
+
+}
+
+cfg {
+  duration = 1260000000000
+  enabled = true
+  type = "json"
+}

provider/dasel/hcl/provider.go

@@ -0,0 +1,13 @@
+package hcl
+
+import (
+	"github.com/tomwright/dasel/v3/parsing/hcl"
+	"gitoa.ru/go-4devs/config/provider/dasel"
+)
+
+const Name = "dasel:hcl"
+
+//nolint:wrapcheck
+func New(data []byte) (dasel.Provider, error) {
+	return dasel.New(data, hcl.HCL, dasel.WithName(Name))
+}

provider/dasel/hcl/provider_test.go

@@ -0,0 +1,35 @@
+package hcl_test
+
+import (
+	"embed"
+	"testing"
+	"time"
+
+	dhcl "gitoa.ru/go-4devs/config/provider/dasel/hcl"
+	"gitoa.ru/go-4devs/config/test"
+	"gitoa.ru/go-4devs/config/test/require"
+)
+
+//go:embed fixture/*
+var fixture embed.FS
+
+func TestProvider(t *testing.T) {
+	t.Parallel()
+
+	js, err := fixture.ReadFile("fixture/config.hcl")
+	require.NoError(t, err)
+
+	prov, derr := dhcl.New(js)
+	require.NoError(t, derr)
+
+	sl := []string{}
+	read := []test.Read{
+		test.NewRead("config title", "app", "name", "title"),
+		test.NewRead(time.Minute, "app.name.timeout"),
+		test.NewReadUnmarshal(&[]string{"name"}, &sl, "app.name.var"),
+		test.NewReadConfig("cfg"),
+		test.NewRead(true, "app", "name", "success"),
+	}
+
+	test.Run(t, prov, read)
+}

provider/dasel/json/fixture/config.json

@@ -0,0 +1,17 @@
+{
+    "app": {
+        "name": {
+            "var": [
+                "name"
+            ],
+            "title": "config title",
+            "timeout": "1m",
+            "success": true
+        }
+    },
+    "cfg": {
+        "duration": 1260000000000,
+        "enabled": true,
+        "type":"json"
+    }
+}

provider/dasel/json/provider.go

@@ -0,0 +1,13 @@
+package json //nolint:revive
+
+import (
+	"github.com/tomwright/dasel/v3/parsing/json"
+	"gitoa.ru/go-4devs/config/provider/dasel"
+)
+
+const Name = "dasel:json"
+
+//nolint:wrapcheck
+func New(data []byte) (dasel.Provider, error) {
+	return dasel.New(data, json.JSON, dasel.WithName(Name))
+}

provider/dasel/json/provider_test.go

@@ -0,0 +1,35 @@
+package json_test
+
+import (
+	"embed"
+	"testing"
+	"time"
+
+	djson "gitoa.ru/go-4devs/config/provider/dasel/json"
+	"gitoa.ru/go-4devs/config/test"
+	"gitoa.ru/go-4devs/config/test/require"
+)
+
+//go:embed fixture/*
+var fixture embed.FS
+
+func TestProvider(t *testing.T) {
+	t.Parallel()
+
+	js, err := fixture.ReadFile("fixture/config.json")
+	require.NoError(t, err)
+
+	prov, derr := djson.New(js)
+	require.NoError(t, derr)
+
+	sl := []string{}
+	read := []test.Read{
+		test.NewRead("config title", "app.name.title"),
+		test.NewRead(time.Minute, "app.name.timeout"),
+		test.NewReadUnmarshal(&[]string{"name"}, &sl, "app.name.var"),
+		test.NewReadConfig("cfg"),
+		test.NewRead(true, "app", "name", "success"),
+	}
+
+	test.Run(t, prov, read)
+}

provider/dasel/provider.go

@@ -0,0 +1,91 @@
+package dasel
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"strings"
+
+	dasel "github.com/tomwright/dasel/v3"
+	"github.com/tomwright/dasel/v3/model"
+	"github.com/tomwright/dasel/v3/parsing"
+	"gitoa.ru/go-4devs/config"
+	"gitoa.ru/go-4devs/config/value"
+)
+
+var _ config.Provider = Provider{} //nolint:exhaustruct
+
+const Name = "dasel"
+
+type Option func(*Provider)
+
+func WithName(in string) Option {
+	return func(p *Provider) {
+		p.name = in
+	}
+}
+
+func New(in []byte, format parsing.Format, opts ...Option) (Provider, error) {
+	reader, err := format.NewReader(parsing.DefaultReaderOptions())
+	if err != nil {
+		return Provider{}, fmt.Errorf("%w:%w", config.ErrInitFactory, err)
+	}
+
+	data, verr := reader.Read(in)
+	if verr != nil {
+		return Provider{}, fmt.Errorf("%w:%w", config.ErrInitFactory, verr)
+	}
+
+	prov := Provider{
+		data: data,
+		key: func(path ...string) string {
+			return strings.Join(path, ".")
+		},
+		name: Name,
+	}
+
+	for _, opt := range opts {
+		opt(&prov)
+	}
+
+	return prov, nil
+}
+
+type Provider struct {
+	data *model.Value
+	key  func(path ...string) string
+	name string
+}
+
+func (p Provider) Value(ctx context.Context, path ...string) (config.Value, error) {
+	selector := p.key(path...)
+
+	data, cnt, err := dasel.Query(ctx, p.data, selector)
+	if err != nil {
+		return nil, fmt.Errorf("query: %w:%w", config.ErrInvalidValue, err)
+	}
+
+	if cnt > 1 {
+		return nil, fmt.Errorf("count: %v:%w", cnt, config.ErrToManyArgs)
+	}
+
+	if cnt == 0 {
+		return value.EmptyValue(), nil
+	}
+
+	val, verr := data[0].GoValue()
+	if verr != nil {
+		return nil, fmt.Errorf("go value: %w:%w", config.ErrInvalidValue, verr)
+	}
+
+	res, merr := json.Marshal(val)
+	if merr != nil {
+		return nil, fmt.Errorf("marshal: %w:%w", config.ErrInvalidValue, merr)
+	}
+
+	return value.JBytes(res), nil
+}
+
+func (p Provider) Name() string {
+	return p.name
+}

provider/env/provider.go

@@ -3,10 +3,13 @@ package env
 import (
 	"context"
 	"fmt"
+	"io"
 	"os"
 	"strings"
 
 	"gitoa.ru/go-4devs/config"
+	"gitoa.ru/go-4devs/config/key"
+	"gitoa.ru/go-4devs/config/param"
 	"gitoa.ru/go-4devs/config/value"
 )
 
@@ -26,6 +29,7 @@ func New(namespace, appName string, opts ...Option) *Provider {
 			return strings.ToUpper(strings.Join(path, "_"))
 		},
 		prefix: strings.ToUpper(namespace + "_" + appName + "_"),
+		name:   "",
 	}
 
 	for _, opt := range opts {
@@ -41,15 +45,68 @@ type Provider struct {
 	prefix string
 }
 
+func (p *Provider) Key(path ...string) string {
+	return p.prefix + p.key(path...)
+}
+
 func (p *Provider) Name() string {
 	return p.name
 }
 
 func (p *Provider) Value(_ context.Context, path ...string) (config.Value, error) {
-	name := p.prefix + p.key(path...)
-	if val, ok := os.LookupEnv(name); ok {
+	if val, ok := os.LookupEnv(p.Key(path...)); ok {
 		return value.JString(val), nil
 	}
 
-	return nil, fmt.Errorf("%v:%w", p.Name(), config.ErrValueNotFound)
+	return nil, fmt.Errorf("%v:%w", p.Name(), config.ErrNotFound)
+}
+
+func (p *Provider) DumpReference(_ context.Context, w io.Writer, opt config.Options) error {
+	return p.writeOptions(w, opt)
+}
+
+func (p *Provider) writeOptions(w io.Writer, opt config.Options, key ...string) error {
+	for idx, option := range opt.Options() {
+		if err := p.writeOption(w, option, key...); err != nil {
+			return fmt.Errorf("option[%d]:%w", idx, err)
+		}
+	}
+
+	return nil
+}
+
+func (p *Provider) writeOption(w io.Writer, opt config.Option, keys ...string) error {
+	if desc := param.Description(opt); desc != "" {
+		if _, derr := fmt.Fprintf(w, "# %v.\n", desc); derr != nil {
+			return fmt.Errorf("write description:%w", derr)
+		}
+	}
+
+	var err error
+
+	switch one := opt.(type) {
+	case config.Group:
+		err = p.writeOptions(w, one, append(keys, one.Name())...)
+	case config.Options:
+		err = p.writeOptions(w, one, keys...)
+	default:
+		def, dok := param.Default(opt)
+
+		prefix := ""
+		if !dok || key.IsWild(keys...) {
+			prefix = "#"
+		}
+
+		if !dok {
+			def = ""
+		}
+
+		_, err = fmt.Fprintf(w, "%s%s=%v\n", prefix, p.Key(append(keys, one.Name())...), def)
+	}
+
+	if err != nil {
+		return fmt.Errorf("%w", err)
+	}
+
+	return nil
 }

provider/env/provider_test.go

@@ -1,18 +1,22 @@
 package env_test
 
 import (
-	"os"
+	"bytes"
+	"context"
 	"testing"
 
+	"gitoa.ru/go-4devs/config"
+	"gitoa.ru/go-4devs/config/definition/group"
+	"gitoa.ru/go-4devs/config/definition/option"
+	"gitoa.ru/go-4devs/config/definition/proto"
 	"gitoa.ru/go-4devs/config/provider/env"
 	"gitoa.ru/go-4devs/config/test"
+	"gitoa.ru/go-4devs/config/test/require"
 )
 
 func TestProvider(t *testing.T) {
-	t.Parallel()
-
-	os.Setenv("FDEVS_CONFIG_DSN", test.DSN)
-	os.Setenv("FDEVS_CONFIG_PORT", "8080")
+	t.Setenv("FDEVS_CONFIG_DSN", test.DSN)
+	t.Setenv("FDEVS_CONFIG_PORT", "8080")
 
 	provider := env.New("fdevs", "config")
 
@@ -22,3 +26,35 @@ func TestProvider(t *testing.T) {
 	}
 	test.Run(t, provider, read)
 }
+
+func TestProvider_DumpReference(t *testing.T) {
+	t.Parallel()
+
+	const expect = `# configure log.
+# level.
+FDEVS_CONFIG_LOG_LEVEL=info
+# configure log service.
+# level.
+#FDEVS_CONFIG_LOG_{SERVICE}_LEVEL=
+`
+
+	ctx := context.Background()
+	prov := env.New("fdevs", "config")
+	buf := bytes.NewBuffer(nil)
+
+	require.NoError(t, prov.DumpReference(ctx, buf, testOptions(t)))
+	require.Equal(t, buf.String(), expect)
+}
+
+func testOptions(t *testing.T) config.Options {
+	t.Helper()
+
+	return group.New("test", "test",
+		group.New("log", "configure log",
+			option.String("level", "level", option.Default("info")),
+			proto.New("service", "configure log service",
+				option.String("level", "level"),
+			),
+		),
+	)
+}

provider/etcd/etcd_test.go

@@ -0,0 +1,48 @@
+package etcd_test
+
+import (
+	"context"
+	"os"
+	"time"
+
+	client "go.etcd.io/etcd/client/v3"
+)
+
+const ConfigJSON = `{"duration":1260000000000,"enabled":true}`
+
+func NewEtcd(ctx context.Context) (*client.Client, error) {
+	dsn, ok := os.LookupEnv("FDEVS_CONFIG_ETCD_HOST")
+	if !ok {
+		dsn = "127.0.0.1:2379"
+	}
+
+	et, err := client.New(client.Config{
+		Endpoints:   []string{dsn},
+		DialTimeout: time.Second,
+	})
+	if err != nil {
+		return nil, err
+	}
+
+	values := map[string]string{
+		"fdevs/config/db_dsn":   "pgsql://user@pass:127.0.0.1:5432",
+		"fdevs/config/duration": "12m",
+		"fdevs/config/port":     "8080",
+		"fdevs/config/maintain": "true",
+		"fdevs/config/start_at": "2020-01-02T15:04:05Z",
+		"fdevs/config/percent":  "0.064",
+		"fdevs/config/count":    "2020",
+		"fdevs/config/int64":    "2021",
+		"fdevs/config/uint64":   "2022",
+		"fdevs/config/config":   ConfigJSON,
+	}
+
+	for name, val := range values {
+		_, err = et.Put(ctx, name, val)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	return et, nil
+}

provider/etcd/go.mod

@@ -0,0 +1,32 @@
+module gitoa.ru/go-4devs/config/provider/etcd
+
+go 1.23
+
+require (
+	github.com/stretchr/testify v1.8.4
+	gitoa.ru/go-4devs/config v0.0.3
+	go.etcd.io/etcd/api/v3 v3.5.11
+	go.etcd.io/etcd/client/v3 v3.5.11
+)
+
+require (
+	github.com/coreos/go-semver v0.3.0 // indirect
+	github.com/coreos/go-systemd/v22 v22.3.2 // indirect
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/gogo/protobuf v1.3.2 // indirect
+	github.com/golang/protobuf v1.5.3 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
+	go.etcd.io/etcd/client/pkg/v3 v3.5.11 // indirect
+	go.uber.org/atomic v1.7.0 // indirect
+	go.uber.org/multierr v1.6.0 // indirect
+	go.uber.org/zap v1.17.0 // indirect
+	golang.org/x/net v0.17.0 // indirect
+	golang.org/x/sys v0.13.0 // indirect
+	golang.org/x/text v0.13.0 // indirect
+	google.golang.org/genproto v0.0.0-20230822172742-b8732ec3820d // indirect
+	google.golang.org/genproto/googleapis/api v0.0.0-20230822172742-b8732ec3820d // indirect
+	google.golang.org/genproto/googleapis/rpc v0.0.0-20230822172742-b8732ec3820d // indirect
+	google.golang.org/grpc v1.59.0 // indirect
+	google.golang.org/protobuf v1.31.0 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+)

provider/etcd/go.sum

@@ -0,0 +1,99 @@
+github.com/coreos/go-semver v0.3.0 h1:wkHLiw0WNATZnSG7epLsujiMCgPAc9xhjJ4tgnAxmfM=
+github.com/coreos/go-semver v0.3.0/go.mod h1:nnelYz7RCh+5ahJtPPxZlU+153eP4D4r3EedlOD2RNk=
+github.com/coreos/go-systemd/v22 v22.3.2 h1:D9/bQk5vlXQFZ6Kwuu6zaiXJ9oTPe68++AzAJc1DzSI=
+github.com/coreos/go-systemd/v22 v22.3.2/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 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/godbus/dbus/v5 v5.0.4/go.mod h1:xhWf0FNVPg57R7Z0UbKHbJfkEywrmjJnf7w5xrFpKfA=
+github.com/gogo/protobuf v1.3.2 h1:Ov1cvc58UF3b5XjBnZv7+opcTcQFZebYjWzi34vdm4Q=
+github.com/gogo/protobuf v1.3.2/go.mod h1:P1XiOD3dCwIKUDQYPy72D8LYyHL2YPYrpS2s69NZV8Q=
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+github.com/golang/protobuf v1.5.3 h1:KhyjKVUg7Usr/dYsdSqoFveMYd5ko72D+zANwlG1mmg=
+github.com/golang/protobuf v1.5.3/go.mod h1:XVQd3VNwM+JqD3oG2Ue2ip4fOMUkwXdXDdiuN0vRsmY=
+github.com/google/go-cmp v0.5.5/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
+github.com/google/go-cmp v0.5.9 h1:O2Tfq5qg4qc4AmwVlvv0oLiVAGB7enBSJ2x2DqQFi38=
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+gopkg.in/yaml.v3 v3.0.0-20210107192922-496545a6307b/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

provider/etcd/provider.go

@@ -0,0 +1,121 @@
+package etcd
+
+import (
+	"context"
+	"fmt"
+	"log"
+	"strings"
+
+	"gitoa.ru/go-4devs/config"
+	"gitoa.ru/go-4devs/config/value"
+	pb "go.etcd.io/etcd/api/v3/mvccpb"
+	client "go.etcd.io/etcd/client/v3"
+)
+
+const (
+	Name      = "etcd"
+	Separator = "/"
+)
+
+var (
+	_ config.Provider      = (*Provider)(nil)
+	_ config.WatchProvider = (*Provider)(nil)
+)
+
+type Client interface {
+	client.KV
+	client.Watcher
+}
+
+func New(namespace, appName string, client Client) *Provider {
+	prov := Provider{
+		client: client,
+		key: func(s ...string) string {
+			return strings.Join(s, Separator)
+		},
+		name:   Name,
+		prefix: namespace + Separator + appName,
+		log: func(_ context.Context, format string, args ...any) {
+			log.Printf(format, args...)
+		},
+	}
+
+	return &prov
+}
+
+type Provider struct {
+	client Client
+	key    func(...string) string
+	name   string
+	prefix string
+	log    func(context.Context, string, ...any)
+}
+
+func (p *Provider) Name() string {
+	return p.name
+}
+
+func (p *Provider) Key(s []string) string {
+	return p.prefix + Separator + p.key(s...)
+}
+
+func (p *Provider) Value(ctx context.Context, path ...string) (config.Value, error) {
+	name := p.Key(path)
+
+	resp, err := p.client.Get(ctx, name, client.WithPrefix())
+	if err != nil {
+		return nil, fmt.Errorf("%w: key:%s, prov:%s", err, name, p.Name())
+	}
+
+	val, err := p.resolve(name, resp.Kvs)
+	if err != nil {
+		return nil, fmt.Errorf("%w: key:%s, prov:%s", err, name, p.Name())
+	}
+
+	return val, nil
+}
+
+func (p *Provider) Watch(ctx context.Context, callback config.WatchCallback, path ...string) error {
+	go func(ctx context.Context, key string, callback config.WatchCallback) {
+		watch := p.client.Watch(ctx, key, client.WithPrevKV(), client.WithPrefix())
+		for w := range watch {
+			kvs, olds := p.getEventKvs(w.Events)
+			if len(kvs) > 0 {
+				newVar, _ := p.resolve(key, kvs)
+				oldVar, _ := p.resolve(key, olds)
+
+				if err := callback(ctx, oldVar, newVar); err != nil {
+					p.log(ctx, "watch callback[%v] %v:%v", p.Name(), path, err)
+				}
+			}
+		}
+	}(ctx, p.Key(path), callback)
+
+	return nil
+}
+
+func (p *Provider) getEventKvs(events []*client.Event) ([]*pb.KeyValue, []*pb.KeyValue) {
+	kvs := make([]*pb.KeyValue, 0, len(events))
+	old := make([]*pb.KeyValue, 0, len(events))
+
+	for i := range events {
+		kvs = append(kvs, events[i].Kv)
+		old = append(old, events[i].PrevKv)
+	}
+
+	return kvs, old
+}
+
+//nolint:nilnil
+func (p *Provider) resolve(key string, kvs []*pb.KeyValue) (config.Value, error) {
+	for _, kv := range kvs {
+		switch {
+		case kv == nil:
+			return nil, nil
+		case string(kv.Key) == key:
+			return value.JBytes(kv.Value), nil
+		}
+	}
+
+	return nil, fmt.Errorf("%w: name %s", config.ErrValueNotFound, key)
+}

provider/etcd/provider_example_test.go

@@ -0,0 +1,121 @@
+package etcd_test
+
+import (
+	"context"
+	"fmt"
+	"log"
+	"sync"
+	"time"
+
+	"gitoa.ru/go-4devs/config"
+	"gitoa.ru/go-4devs/config/provider/etcd"
+)
+
+func ExampleClient_Value() {
+	const (
+		namespace = "fdevs"
+		appName   = "config"
+	)
+
+	ctx := context.Background()
+
+	// configure etcd client
+	etcdClient, err := NewEtcd(ctx)
+	if err != nil {
+		log.Print(err)
+
+		return
+	}
+
+	config, err := config.New(
+		etcd.New(namespace, appName, etcdClient),
+	)
+	if err != nil {
+		log.Print(err)
+
+		return
+	}
+
+	enabled, err := config.Value(ctx, "maintain")
+	if err != nil {
+		log.Print("maintain ", err)
+
+		return
+	}
+
+	fmt.Printf("maintain from etcd: %v\n", enabled.Bool())
+	// Output:
+	// maintain from etcd: true
+}
+
+func ExampleClient_Watch() {
+	const (
+		namespace = "fdevs"
+		appName   = "config"
+	)
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	// configure etcd client
+	etcdClient, err := NewEtcd(ctx)
+	if err != nil {
+		log.Print(err)
+
+		return
+	}
+
+	_, err = etcdClient.Put(ctx, "fdevs/config/example_db_dsn", "pgsql://user@pass:127.0.0.1:5432")
+	if err != nil {
+		log.Print(err)
+
+		return
+	}
+
+	defer func() {
+		cancel()
+
+		if _, err = etcdClient.Delete(context.Background(), "fdevs/config/example_db_dsn"); err != nil {
+			log.Print(err)
+
+			return
+		}
+	}()
+
+	watcher, err := config.New(
+		etcd.New(namespace, appName, etcdClient),
+	)
+	if err != nil {
+		log.Print(err)
+
+		return
+	}
+
+	wg := sync.WaitGroup{}
+	wg.Add(1)
+
+	err = watcher.Watch(ctx, func(_ context.Context, oldVar, newVar config.Value) error {
+		fmt.Println("update example_db_dsn old: ", oldVar.String(), " new:", newVar.String())
+		wg.Done()
+
+		return nil
+	}, "example_db_dsn")
+	if err != nil {
+		log.Print(err)
+
+		return
+	}
+
+	time.AfterFunc(time.Second, func() {
+		if _, err := etcdClient.Put(ctx, "fdevs/config/example_db_dsn", "mysql://localhost:5432"); err != nil {
+			log.Print(err)
+
+			return
+		}
+	})
+
+	wg.Wait()
+
+	// Output:
+	// update example_db_dsn old:  pgsql://user@pass:127.0.0.1:5432  new: mysql://localhost:5432
+}