Merge pull request 'update pos argument' (#25) from arg into master

Reviewed-on: #25

.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 +4,9 @@ import (
 	"context"
 	"errors"
 	"fmt"
-	"sync"
-	"sync/atomic"
 )
 
-func Must(providers ...interface{}) *Client {
+func Must(providers ...any) *Client {
 	client, err := New(providers...)
 	if err != nil {
 		panic(err)
@@ -17,7 +15,7 @@ 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)),
 	}
@@ -27,11 +25,7 @@ func New(providers ...interface{}) (*Client, error) {
 		case Provider:
 			client.providers[idx] = current
 		case Factory:
-			client.providers[idx] = &provider{
-				factory: func(ctx context.Context) (Provider, error) {
-					return current(ctx, client)
-				},
-			}
+			client.providers[idx] = WrapFactory(current, client)
 		default:
 			return nil, fmt.Errorf("provier[%d]: %w %T", idx, ErrUnknowType, prov)
 		}
@@ -40,60 +34,6 @@ func New(providers ...interface{}) (*Client, error) {
 	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
 }
@@ -111,7 +51,7 @@ 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 +72,7 @@ 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 +82,18 @@ 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
+}

client_example_test.go

@@ -0,0 +1,174 @@
+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/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(),
+		config.Factory(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
+}

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 +1,23 @@
+package definition
+
+import (
+	"gitoa.ru/go-4devs/config"
+)
+
+func New(opts ...config.Option) *Definition {
+	return &Definition{
+		options: opts,
+	}
+}
+
+type Definition struct {
+	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
+}

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
+
+	imp       *pkg.Imports
+	Configure []string
+	OutName   string
+}
+
+func (b Boot) Imports() []pkg.Import {
+	return b.imp.Imports()
+}
+
+type Config interface {
+	File() string
+	Methods() []string
+	SkipContext() bool
+	Prefix() string
+	Suffix() string
+	FullPkg() string
+	Pkg() string
+}
+
+func Bootstrap(ctx context.Context, cfg Config) (string, error) {
+	fInfo, err := os.Stat(cfg.File())
+	if err != nil {
+		return "", fmt.Errorf("stat:%w", 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/definition/generate",
+			"os",
+			"fmt",
+			"go/format",
+			pkgPath,
+		)
+
+	data := Boot{
+		imp:       imports,
+		Configure: cfg.Methods(),
+		OutName:   fInfo.Name()[0:len(fInfo.Name())-3] + "_config.go",
+		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 +1,59 @@
+//go:build ignore
+// +build ignore
+
+package main
+
+import (
+	{{range .Imports}}
+    {{- .Alias }}"{{ .Package }}"
+    {{end}}
+)
+
+func main() {
+	if err := run(); err != nil {
+		fmt.Fprintln(os.Stderr, err)
+		os.Exit(1)
+	}
+}
+
+func run() error {
+	ctx := context.Background()
+
+	f, err := os.Create("{{.OutName}}")
+	if err != nil {
+		return err
+	}
+
+	defs:=make([]generate.Input,0)
+{{ range .Configure }} 
+	def{{.}} := definition.New()
+	if err := {{$.Pkg}}.{{.}}(ctx, def{{.}}); err != nil {
+		return err
+	}
+	defs = append(defs,generate.NewInput("{{.}}",def{{.}}))
+{{ end }}
+
+	opts := make([]generate.Option,0)
+	{{ if .SkipContext }}opts = append(opts, generate.WithSkipContext){{ end }}
+	opts = append(opts, 
+		generate.WithPrefix("{{.Prefix}}"),
+		generate.WithSuffix("{{.Suffix}}"),
+		generate.WithFullPkg("{{.FullPkg}}"),
+	)
+
+	if gerr := generate.Run(ctx,generate.NewConfig(opts...),f, defs...);gerr != nil {
+		return gerr
+	}
+
+	in, err := os.ReadFile(f.Name())
+	if err != nil {
+		return err
+	}
+
+	out, err := format.Source(in)
+	if err != nil {
+		return err
+	}
+
+	return os.WriteFile(f.Name(), out, 0644)
+}

definition/generate/example/config.go

@@ -0,0 +1,37 @@
+package example
+
+import (
+	"context"
+
+	"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 Level string
+
+func (l *Level) UnmarshalText(in []byte) error {
+	data := string(in)
+	*l = Level(data)
+
+	return nil
+}
+
+func Config(_ 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", Level("")),
+			proto.New("service", "servise logger", option.New("level", "log level", Level(""))),
+		),
+	)
+
+	return nil
+}

definition/generate/example/config_config.go

@@ -0,0 +1,206 @@
+// Code generated gitoa.ru/go-4devs/config DO NOT EDIT.
+package example
+
+import (
+	context "context"
+	fmt "fmt"
+	config "gitoa.ru/go-4devs/config"
+)
+
+func WithInputConfigLog(log func(context.Context, string, ...any)) func(*InputConfig) {
+	return func(ci *InputConfig) {
+		ci.log = log
+	}
+}
+
+func NewInputConfig(prov config.Provider, opts ...func(*InputConfig)) InputConfig {
+	i := InputConfig{
+		Provider: prov,
+		log: func(_ context.Context, format string, args ...any) {
+			fmt.Printf(format, args...)
+		},
+	}
+
+	for _, opt := range opts {
+		opt(&i)
+	}
+
+	return i
+}
+
+type InputConfig struct {
+	config.Provider
+	log func(context.Context, string, ...any)
+}
+
+// readTest test string.
+func (i InputConfig) 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 InputConfig) ReadTest() (string, error) {
+	return i.readTest(context.Background())
+}
+
+// Test test string.
+func (i InputConfig) Test() string {
+	val, err := i.readTest(context.Background())
+	if err != nil {
+		i.log(context.Background(), "get [%v]: %v", []string{"test"}, err)
+	}
+
+	return val
+}
+
+type InputConfigUser struct {
+	InputConfig
+}
+
+// User configure user.
+func (i InputConfig) User() InputConfigUser {
+	return InputConfigUser{i}
+}
+
+// readName name.
+func (i InputConfigUser) readName(ctx context.Context) (v string, e error) {
+	val, err := i.Value(ctx, "user", "name")
+	if err != nil {
+		i.log(context.Background(), "read [%v]: %v", []string{"user", "name"}, err)
+
+		return "4devs", nil
+	}
+
+	return val.ParseString()
+
+}
+
+// ReadName name.
+func (i InputConfigUser) ReadName(ctx context.Context) (string, error) {
+	return i.readName(ctx)
+}
+
+// Name name.
+func (i InputConfigUser) Name(ctx context.Context) string {
+	val, err := i.readName(ctx)
+	if err != nil {
+		i.log(ctx, "get [%v]: %v", []string{"user", "name"}, err)
+	}
+
+	return val
+}
+
+// readPass password.
+func (i InputConfigUser) readPass(ctx context.Context) (v string, e error) {
+	val, err := i.Value(ctx, "user", "pass")
+	if err != nil {
+		return v, fmt.Errorf("read [%v]:%w", []string{"user", "pass"}, err)
+
+	}
+
+	return val.ParseString()
+
+}
+
+// ReadPass password.
+func (i InputConfigUser) ReadPass(ctx context.Context) (string, error) {
+	return i.readPass(ctx)
+}
+
+// Pass password.
+func (i InputConfigUser) Pass(ctx context.Context) string {
+	val, err := i.readPass(ctx)
+	if err != nil {
+		i.log(ctx, "get [%v]: %v", []string{"user", "pass"}, err)
+	}
+
+	return val
+}
+
+type InputConfigLog struct {
+	InputConfig
+}
+
+// Log configure logger.
+func (i InputConfig) Log() InputConfigLog {
+	return InputConfigLog{i}
+}
+
+// readLevel log level.
+func (i InputConfigLog) 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("read [%v]:%w", []string{"log", "level"}, perr)
+	}
+
+	return v, v.UnmarshalText([]byte(pval))
+}
+
+// ReadLevel log level.
+func (i InputConfigLog) ReadLevel(ctx context.Context) (Level, error) {
+	return i.readLevel(ctx)
+}
+
+// Level log level.
+func (i InputConfigLog) Level(ctx context.Context) Level {
+	val, err := i.readLevel(ctx)
+	if err != nil {
+		i.log(ctx, "get [%v]: %v", []string{"log", "level"}, err)
+	}
+
+	return val
+}
+
+type InputConfigLogService struct {
+	InputConfigLog
+	service string
+}
+
+// Service servise logger.
+func (i InputConfigLog) Service(key string) InputConfigLogService {
+	return InputConfigLogService{i, key}
+}
+
+// readLevel log level.
+func (i InputConfigLogService) 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("read [%v]:%w", []string{"log", i.service, "level"}, perr)
+	}
+
+	return v, v.UnmarshalText([]byte(pval))
+}
+
+// ReadLevel log level.
+func (i InputConfigLogService) ReadLevel(ctx context.Context) (Level, error) {
+	return i.readLevel(ctx)
+}
+
+// Level log level.
+func (i InputConfigLogService) Level(ctx context.Context) Level {
+	val, err := i.readLevel(ctx)
+	if err != nil {
+		i.log(ctx, "get [%v]: %v", []string{"log", i.service, "level"}, err)
+	}
+
+	return val
+}

definition/generate/example/generate_test.go

@@ -0,0 +1,59 @@
+package example_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/example"
+)
+
+func TestGenerate_Bootstrap(t *testing.T) {
+	t.SkipNow()
+	t.Parallel()
+
+	ctx := context.Background()
+	options := definition.New()
+	_ = example.Config(ctx, options)
+
+	cfg, _ := generate.NewGConfig("./config.go",
+		generate.WithMethods("Config"),
+		generate.WithFullPkg("gitoa.ru/go-4devs/config/definition/generate/example"),
+	)
+
+	path, err := bootstrap.Bootstrap(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()
+	_ = example.Config(ctx, options)
+
+	cfg, _ := generate.NewGConfig("./config.go",
+		generate.WithMethods("Config"),
+		generate.WithFullPkg("gitoa.ru/go-4devs/config/definition/generate/example"),
+	)
+
+	err := generate.Generate(ctx, cfg)
+	if err != nil {
+		t.Error(err)
+		t.FailNow()
+	}
+
+	t.FailNow()
+}

definition/generate/exec.go

@@ -0,0 +1,78 @@
+package generate
+
+import (
+	"context"
+	"fmt"
+	"go/format"
+	"os"
+	"os/exec"
+	"path/filepath"
+
+	"gitoa.ru/go-4devs/config/definition/generate/bootstrap"
+)
+
+func NewGConfig(fname string, opts ...Option) (Config, error) {
+	opts = append([]Option{
+		WithFile(fname),
+	}, opts...)
+
+	return NewConfig(opts...), nil
+}
+
+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 +1,233 @@
+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"
+	"gitoa.ru/go-4devs/config/param"
+)
+
+type Option func(*Config)
+
+func WithSkipContext(c *Config) {
+	view.WithSkipContext(c.Params)
+}
+
+func WithPrefix(name string) Option {
+	return func(c *Config) {
+		c.prefix = name
+	}
+}
+
+func WithSuffix(name string) Option {
+	return func(c *Config) {
+		c.suffix = name
+	}
+}
+
+// WithMethods set methosd.
+//
+// generate.WithMethods(runtime.FuncForPC(reflect.ValueOf(configure).Pointer()).Name()).
+func WithMethods(in ...string) Option {
+	return func(c *Config) {
+		c.methods = in
+	}
+}
+
+func WithOutName(in string) Option {
+	return func(c *Config) {
+		c.outName = in
+	}
+}
+
+func WithFile(in string) Option {
+	return func(c *Config) {
+		c.file = in
+	}
+}
+
+func WithFullPkg(in string) Option {
+	return func(c *Config) {
+		c.fullPkg = in
+	}
+}
+
+func NewConfig(opts ...Option) Config {
+	var cfg Config
+
+	cfg.Params = param.New()
+	cfg.prefix = "Input"
+
+	for _, opt := range opts {
+		opt(&cfg)
+	}
+
+	return cfg
+}
+
+type Config struct {
+	param.Params
+
+	methods   []string
+	prefix    string
+	suffix    string
+	fullPkg   string
+	pkg       string
+	file      string
+	buildTags string
+	outName   string
+}
+
+func (c Config) BuildTags() string {
+	return c.buildTags
+}
+
+func (c Config) Pkg() string {
+	if c.pkg == "" {
+		if idx := strings.LastIndex(c.fullPkg, "/"); idx != -1 {
+			c.pkg = c.fullPkg[idx+1:]
+		}
+	}
+
+	return c.pkg
+}
+
+func (c Config) FullPkg() string {
+	return c.fullPkg
+}
+
+func (c Config) SkipContext() bool {
+	return view.IsSkipContext(c.Params)
+}
+
+func (c Config) Methods() []string {
+	return c.methods
+}
+
+func (c Config) Prefix() string {
+	return c.prefix
+}
+
+func (c Config) Suffix() string {
+	return c.suffix
+}
+
+func (c Config) File() string {
+	return c.file
+}
+
+func (c Config) OutName() string {
+	return c.outName
+}
+
+//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, cfg Config, w io.Writer, inputs ...Input) error {
+	data := Data{
+		Config: cfg,
+		imp:    pkg.NewImports(cfg.FullPkg()).Adds("fmt", "context", "gitoa.ru/go-4devs/config"),
+	}
+
+	var buff bytes.Buffer
+
+	for _, in := range inputs {
+		vi := view.NewViews(in.Method(), data.Params, in.Options(), view.WithKeys())
+
+		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 {
+	Config
+
+	imp *pkg.Imports
+}
+
+func (f Data) Imports() []pkg.Import {
+	return f.imp.Imports()
+}
+
+func (f Data) StructName(name string) string {
+	return f.Prefix() + FuncName(name) + f.Suffix()
+}
+
+func (f Data) FuncName(in string) string {
+	return FuncName(in)
+}
+
+func (f Data) AddType(pkg string) (string, error) {
+	short, err := f.imp.AddType(pkg)
+	if err != nil {
+		return "", fmt.Errorf("data: %w", err)
+	}
+
+	return short, nil
+}
+
+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()
+}
+
+func NewInput(method string, options config.Options) Input {
+	return Input{
+		method:  method,
+		options: options,
+	}
+}
+
+type Input struct {
+	options config.Options
+	method  string
+}
+
+func (i Input) Method() string {
+	return i.method
+}
+
+func (i Input) Options() config.Options {
+	return i.options
+}

definition/generate/generate_test.go

@@ -0,0 +1,33 @@
+package generate_test
+
+import (
+	"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 LogLevel string
+
+func (l *LogLevel) UnmarshalText(in []byte) error {
+	data := string(in)
+	*l = LogLevel(data)
+
+	return nil
+}
+
+func Configure(def *definition.Definition) {
+	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(""))),
+		),
+	)
+}

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 +1,106 @@
+package pkg
+
+import (
+	"fmt"
+	"strconv"
+	"strings"
+)
+
+func NewImports(pkg string) *Imports {
+	imp := Imports{
+		data: make(map[string]string),
+		pkg:  pkg,
+	}
+
+	return &imp
+}
+
+type Imports struct {
+	data map[string]string
+	pkg  string
+}
+
+func (i *Imports) 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 *Imports) 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 *Imports) 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 *Imports) Adds(pkgs ...string) *Imports {
+	for _, pkg := range pkgs {
+		i.Add(pkg)
+	}
+
+	return i
+}
+
+func (i *Imports) 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,
+	}
+}
+
+type Import struct {
+	Alias   string
+	Package string
+}

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.Split(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.ParentName() + "_" + d.View.Name())
+}
+
+func (d ViewData) FuncName() string {
+	return d.Rendering.FuncName(d.View.FuncName())
+}
+
+func (d ViewData) ParentName() string {
+	name := d.View.ParentName()
+	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(append(d.View.Keys(), d.Name()), 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("read [%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("read [%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("read [%v]:%w", []string{ {{- .Keys "i" -}} }, perr)
+    }
+
+    return {{.Value}}, {{.Value}}.UnmarshalText([]byte(pval))
+{{- end }}

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

@@ -0,0 +1,25 @@
+func With{{.StructName}}Log(log func(context.Context, string, ...any)) func(*{{.StructName}}) {
+	return func(ci *{{.StructName}}) {
+		ci.log = log
+	}
+}
+
+func New{{.StructName}}(prov config.Provider, opts ...func(*{{.StructName}})) {{.StructName}} {
+	i := {{.StructName}}{
+		Provider: prov,
+		log: func(_ context.Context, format string, args ...any) {
+			fmt.Printf(format, args...)
+		},
+	}
+
+	for _, opt := range opts {
+		opt(&i)
+	}
+
+	return i
+}
+
+type {{.StructName}} struct {
+	config.Provider
+	log   func(context.Context, string, ...any)
+}

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

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

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

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

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

@@ -0,0 +1,9 @@
+type {{.StructName}} struct {
+    {{.ParentName}}
+    {{ .Name }} string
+}
+
+// {{.FuncName}} {{.Description}}.
+func (i {{.ParentName}}) {{.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.Ptr {
+		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("read [%v]:%w",[]string{"flagValue"}, perr)
+    }
+
+    return v, v.Set(pval)`
+
+	viewData := render.NewViewData(nil, view.NewView(option.New("flag_value", "flag desc", flagValue(0)), nil))
+	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)), nil))
+	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)), nil))
+	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("")), nil))
+	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("read [%v]:%w", []string{"tvalue"}, perr)
+    }
+
+    return v, v.UnmarshalText([]byte(pval))`
+
+	viewData := render.NewViewData(nil, view.NewView(option.New("tvalue", "unmarshal text desc", textData("")), nil))
+	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}}
+    {{- .Alias }} "{{ .Package }}"
+    {{end}}
+)

definition/generate/view/view.go

@@ -0,0 +1,191 @@
+package view
+
+import (
+	"fmt"
+	"reflect"
+
+	"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
+)
+
+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(name string) Option {
+	return func(v *View) {
+		v.parent = name
+	}
+}
+
+func WithKeys(keys ...string) Option {
+	return func(v *View) {
+		v.keys = keys
+	}
+}
+
+func NewViews(name string, get param.Params, option config.Options, opts ...Option) View {
+	view := newView(name, get, option, opts...)
+
+	for _, op := range option.Options() {
+		view.children = append(view.children, NewView(op, get, WithParent(name)))
+	}
+
+	return view
+}
+
+type IOption any
+
+func newView(name string, get param.Params, in any, opts ...Option) View {
+	vi := View{
+		kind:     reflect.TypeOf(in),
+		name:     name,
+		Params:   get,
+		dtype:    param.Type(get),
+		children: nil,
+		keys:     nil,
+		parent:   "",
+	}
+
+	for _, opt := range opts {
+		opt(&vi)
+	}
+
+	return vi
+}
+
+func NewView(opt config.Option, get param.Params, opts ...Option) View {
+	vi := newView(opt.Name(), param.Chain(get, opt), opt, opts...)
+
+	if data, ok := opt.(config.Group); ok {
+		for _, chi := range data.Options() {
+			vi.children = append(vi.children, NewView(
+				chi,
+				param.Chain(vi.Params, chi),
+				WithParent(vi.ParentName()+"_"+opt.Name()),
+				WithKeys(append(vi.keys, opt.Name())...),
+			))
+		}
+	}
+
+	return vi
+}
+
+type View struct {
+	param.Params
+
+	children []View
+	keys     []string
+	kind     reflect.Type
+	name     string
+	parent   string
+	dtype    any
+}
+
+func (v View) Types() []any {
+	types := make([]any, 0)
+	if v.dtype != nil {
+		types = append(types, v.dtype)
+	}
+
+	for _, child := range v.children {
+		types = append(types, child.Types()...)
+	}
+
+	return types
+}
+
+func (v View) Kind() reflect.Type {
+	return v.kind
+}
+
+func (v View) Views() []View {
+	return v.children
+}
+
+func (v View) Param(key any) string {
+	data, ok := v.Params.Param(key)
+	if !ok {
+		return ""
+	}
+
+	if res, ok := data.(string); ok {
+		return res
+	}
+
+	return fmt.Sprintf("%v", data)
+}
+
+func (v View) SkipContext() bool {
+	return IsSkipContext(v.Params)
+}
+
+func (v View) Name() string {
+	return v.name
+}
+
+func (v View) Keys() []string {
+	return v.keys
+}
+
+func (v View) Type() any {
+	return v.dtype
+}
+
+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) ParentName() string {
+	return v.parent
+}
+
+func (v View) Description() string {
+	return option.DataDescription(v.Params)
+}
+
+func (v View) Default() any {
+	data, ok := option.DataDefaut(v.Params)
+	if !ok {
+		return nil
+	}
+
+	return data
+}
+
+func (v View) HasDefault() bool {
+	return option.HasDefaut(v.Params)
+}

definition/group/group.go

@@ -0,0 +1,34 @@
+package group
+
+import (
+	"gitoa.ru/go-4devs/config"
+	"gitoa.ru/go-4devs/config/definition/option"
+	"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(option.Description(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
+}

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, Description(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 +1,125 @@
+package option
+
+import (
+	"gitoa.ru/go-4devs/config/param"
+)
+
+type key int
+
+const (
+	paramHidden key = iota + 1
+	paramDefault
+	paramDesc
+	paramRequired
+	paramSlice
+	paramBool
+	paramPos
+	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 func(p param.Params) param.Params {
+		return param.With(p, paramPos, 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 func(v param.Params) param.Params {
+		return param.With(v, paramDefault, in)
+	}
+}
+
+func Description(in string) param.Option {
+	return func(v param.Params) param.Params {
+		return param.With(v, paramDesc, in)
+	}
+}
+
+func HasDefaut(fn param.Params) bool {
+	_, ok := fn.Param(paramDefault)
+
+	return ok
+}
+
+func DataPosition(fn param.Params) (uint64, bool) {
+	return param.Uint64(paramPos, fn)
+}
+
+func DataDefaut(fn param.Params) (any, bool) {
+	data, ok := fn.Param(paramDefault)
+
+	return data, ok
+}
+
+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
+}
+
+func DataDescription(fn param.Params) string {
+	data, _ := param.String(fn, paramDesc)
+
+	return data
+}

definition/proto/proto.go

@@ -0,0 +1,33 @@
+package proto
+
+import (
+	"gitoa.ru/go-4devs/config"
+	"gitoa.ru/go-4devs/config/definition/option"
+	"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(option.Description(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 +1,98 @@
+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(ctx, prov)
+		},
+		mu:       sync.Mutex{},
+		done:     0,
+		provider: nil,
+	}
+}
+
+type WrapProvider struct {
+	mu       sync.Mutex
+	done     uint32
+	provider Provider
+	factory  func(ctx context.Context) (Provider, error)
+}
+
+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 {
+	if err := p.init(context.Background()); err != nil {
+		return fmt.Sprintf("%T", p.provider)
+	}
+
+	return p.provider.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 +1,3 @@
 module gitoa.ru/go-4devs/config
 
-go 1.21
+go 1.23

key/map.go

@@ -0,0 +1,121 @@
+package key
+
+import (
+	"strings"
+)
+
+const (
+	prefixByPath = "byPath"
+)
+
+func newMap() *Map {
+	return &Map{
+		idx:      0,
+		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) {
+	for name := range m.children {
+		if after, ok := strings.CutPrefix(path, name); ok {
+			data := m.children[name]
+			if len(after) == 0 {
+				return data, true
+			}
+
+			after, ok = strings.CutPrefix(after, sep)
+			if !ok {
+				return data, false
+			}
+
+			if data.wild == nil {
+				return data.byPath(after, sep)
+			}
+
+			if idx := strings.Index(after, sep); idx != -1 {
+				return data.wild.byPath(after[idx+1:], sep)
+			}
+
+			return data, false
+		}
+	}
+
+	return m, false
+}
+
+func (m *Map) find(path []string) (*Map, bool) {
+	name := path[0]
+
+	last := len(path) == 1
+	if !last {
+		path = path[1:]
+	}
+
+	if m.wild != nil {
+		return m.wild.find(path)
+	}
+
+	data, ok := m.children[name]
+	if !ok {
+		return data, false
+	}
+
+	if last {
+		return data, data.children == nil
+	}
+
+	return data.find(path)
+}

key/map_test.go

@@ -0,0 +1,83 @@
+package key_test
+
+import (
+	"testing"
+
+	"gitoa.ru/go-4devs/config/key"
+)
+
+func TestMap_ByPath(t *testing.T) {
+	t.Parallel()
+
+	const (
+		expID int = 1
+		newID int = 42
+	)
+
+	data := key.Map{}
+	data.Add(expID, []string{"test", "data", "three"})
+	data.Add(expID, []string{"test", "other"})
+	data.Add(newID, []string{"new", "{data}", "test"})
+
+	idx, ok := data.Index(key.ByPath("test-other", "-"))
+	if !ok {
+		t.Error("key not found")
+	}
+
+	if idx != expID {
+		t.Errorf("idx exp:%v got:%v", expID, idx)
+	}
+
+	if nidx, nok := data.Index(key.ByPath("new-service-test", "-")); !nok && nidx != newID {
+		t.Errorf("idx exp:%v got:%v", newID, nidx)
+	}
+}
+
+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
+		newID int = 42
+	)
+
+	data := key.Map{}
+	data.Add(expID, []string{"test", "{data}", "id"})
+	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)
+	}
+}

key/wild.go

@@ -0,0 +1,15 @@
+package key
+
+const minWildCount = 3
+
+func IsWild(name string) bool {
+	if len(name) < minWildCount {
+		return false
+	}
+
+	return name[0] == '{' && name[len(name)-1] == '}'
+}
+
+func Wild(name string) string {
+	return "{" + name + "}"
+}

param/helper.go

@@ -0,0 +1,34 @@
+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 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 +1,30 @@
+package param
+
+type key int
+
+const (
+	paramTimeFormat key = iota + 1
+	paramType
+)
+
+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
+}

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)
+	}
+}

provider.go

@@ -1,14 +1,14 @@
 package config
 
-import "context"
+import (
+	"context"
+
+	"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
@@ -18,3 +18,33 @@ type WatchProvider interface {
 }
 
 type Factory func(ctx context.Context, cfg Provider) (Provider, error)
+
+type Option interface {
+	Name() string
+	Param(key any) (any, bool)
+}
+
+type Group interface {
+	Option
+	Options
+}
+
+type Options interface {
+	Options() []Option
+}
+
+type BindProvider interface {
+	Provider
+
+	Bind(ctx context.Context, data Variables) error
+}
+
+type Variables interface {
+	ByName(name ...string) (Variable, error)
+	ByParam(filter param.Has) (Variable, error)
+	Variables() []Variable
+}
+
+type Definition interface {
+	Add(opts ...Option)
+}

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 +1,38 @@
+package arg
+
+import (
+	"sync/atomic"
+
+	"gitoa.ru/go-4devs/config/param"
+)
+
+type keyParam int
+
+const (
+	paramArgument keyParam = iota + 1
+)
+
+//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 +2,230 @@ package arg
 
 import (
 	"context"
-	"encoding/json"
 	"fmt"
 	"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)
+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.skip = 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 New(opts ...func(*Argv)) *Argv {
+	arg := &Argv{
+		args: nil,
+		pos:  0,
+		Map:  memory.Map{},
+		skip: 1,
 	}
 
 	for _, opt := range opts {
-		opt(&prov)
+		opt(arg)
 	}
 
-	return &prov
+	arg.args = os.Args[arg.skip:]
+
+	return arg
 }
 
-type Provider struct {
-	args map[string][]string
-	key  func(...string) string
-	name string
+type Argv struct {
+	memory.Map
+
+	args []string
+	pos  uint64
+	skip int
 }
 
-// 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) 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], 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 +262,3 @@ 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

@@ -65,5 +65,5 @@ 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 +1,42 @@
+package chain
+
+import (
+	"context"
+	"fmt"
+
+	"gitoa.ru/go-4devs/config"
+)
+
+const Name = "chain"
+
+func New(c ...config.Provider) config.BindProvider {
+	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
+}

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

@@ -26,6 +26,7 @@ func New(namespace, appName string, opts ...Option) *Provider {
 			return strings.ToUpper(strings.Join(path, "_"))
 		},
 		prefix: strings.ToUpper(namespace + "_" + appName + "_"),
+		name:   "",
 	}
 
 	for _, opt := range opts {
@@ -51,5 +52,5 @@ func (p *Provider) Value(_ context.Context, path ...string) (config.Value, error
 		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)
 }

provider/env/provider_test.go

@@ -1,7 +1,6 @@
 package env_test
 
 import (
-	"os"
 	"testing"
 
 	"gitoa.ru/go-4devs/config/provider/env"
@@ -9,10 +8,8 @@ import (
 )
 
 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")
 

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=
+github.com/golang/protobuf v1.5.0/go.mod h1:FsONVRAS9T7sI+LIUmWTfcYkHO4aIWwzhcaSAoJOfIk=
+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=
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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
+}

provider/etcd/provider_test.go

@@ -0,0 +1,118 @@
+package etcd_test
+
+import (
+	"context"
+	"fmt"
+	"sync"
+	"sync/atomic"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+	"gitoa.ru/go-4devs/config"
+	"gitoa.ru/go-4devs/config/provider/etcd"
+	"gitoa.ru/go-4devs/config/test"
+	"gitoa.ru/go-4devs/config/test/require"
+)
+
+func TestProvider(t *testing.T) {
+	t.Parallel()
+
+	ctx := context.Background()
+
+	et, err := NewEtcd(ctx)
+	require.NoError(t, err)
+
+	provider := etcd.New("fdevs", "config", et)
+	read := []test.Read{
+		test.NewRead(test.DSN, "db_dsn"),
+		test.NewRead(12*time.Minute, "duration"),
+		test.NewRead(8080, "port"),
+		test.NewRead(true, "maintain"),
+		test.NewRead(test.Time("2020-01-02T15:04:05Z"), "start_at"),
+		test.NewRead(.064, "percent"),
+		test.NewRead(uint(2020), "count"),
+		test.NewRead(int64(2021), "int64"),
+		test.NewRead(int64(2022), "uint64"),
+		test.NewReadConfig("config"),
+	}
+	test.Run(t, provider, read)
+}
+
+func value(cnt int32) string {
+	return fmt.Sprintf("test data: %d", cnt)
+}
+
+func TestWatcher(t *testing.T) {
+	t.Parallel()
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	key := "test_watch"
+
+	et, err := NewEtcd(ctx)
+	require.NoError(t, err)
+
+	defer func() {
+		_, err = et.Delete(context.Background(), "fdevs/config/test_watch")
+		require.NoError(t, err)
+	}()
+
+	var cnt, cnt2 int32
+
+	prov := etcd.New("fdevs", "config", et)
+	wg := sync.WaitGroup{}
+	wg.Add(6)
+
+	watch := func(cnt *int32) config.WatchCallback {
+		return func(_ context.Context, oldVar, newVar config.Value) error {
+			switch *cnt {
+			case 0:
+				assert.Equal(t, value(*cnt), newVar.String())
+				assert.Nil(t, oldVar)
+			case 1:
+				assert.Equal(t, value(*cnt), newVar.String())
+				assert.Equal(t, value(*cnt-1), oldVar.String())
+			case 2:
+				_, perr := newVar.ParseString()
+				require.NoError(t, perr)
+				assert.Empty(t, newVar.String())
+				assert.Equal(t, value(*cnt-1), oldVar.String())
+			default:
+				t.Error("unexpected watch")
+				t.Fail()
+			}
+
+			wg.Done()
+			atomic.AddInt32(cnt, 1)
+
+			return nil
+		}
+	}
+
+	err = prov.Watch(ctx, watch(&cnt), key)
+	err = prov.Watch(ctx, watch(&cnt2), key)
+	require.NoError(t, err)
+
+	time.AfterFunc(time.Second, func() {
+		_, err = et.Put(ctx, "fdevs/config/test_watch", value(0))
+		require.NoError(t, err)
+		_, err = et.Put(ctx, "fdevs/config/test_watch", value(1))
+		require.NoError(t, err)
+		_, err = et.Delete(ctx, "fdevs/config/test_watch")
+		require.NoError(t, err)
+	})
+
+	time.AfterFunc(time.Second*10, func() {
+		assert.Fail(t, "failed watch after 5 sec")
+		cancel()
+	})
+
+	go func() {
+		wg.Wait()
+		cancel()
+	}()
+
+	<-ctx.Done()
+}

provider/ini/go.mod

@@ -0,0 +1,10 @@
+module gitoa.ru/go-4devs/config/provider/ini
+
+go 1.23
+
+require (
+	gitoa.ru/go-4devs/config v0.0.3
+	gopkg.in/ini.v1 v1.67.0
+)
+
+require github.com/stretchr/testify v1.11.1 // indirect

provider/ini/go.sum

@@ -0,0 +1,12 @@
+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/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/stretchr/testify v1.11.1 h1:7s2iGBzp5EwR7/aIZr8ao5+dra3wiQyKjjFuvgVKu7U=
+github.com/stretchr/testify v1.11.1/go.mod h1:wZwfW3scLgRK+23gO65QZefKpKQRnfz6sD981Nm4B6U=
+gitoa.ru/go-4devs/config v0.0.3 h1:+ecwDQj4fneJCh2uLNNAonm4cUJdGmlfxUsFhQRI9Ko=
+gitoa.ru/go-4devs/config v0.0.3/go.mod h1:UINWnObZA0nLiJro+TtavUBBvN0cSt17aRHOk20pP74=
+gopkg.in/ini.v1 v1.67.0 h1:Dgnx+6+nfE+IfzjUEISNeydPJh9AXNNsWbGP9KzCsOA=
+gopkg.in/ini.v1 v1.67.0/go.mod h1:pNLf8WUiyNEtQjuu5G5vTm06TEv9tsIgeAvK8hOrP4k=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

provider/ini/provider.go

@@ -0,0 +1,58 @@
+package ini
+
+import (
+	"context"
+	"fmt"
+	"strings"
+
+	"gitoa.ru/go-4devs/config"
+	"gitoa.ru/go-4devs/config/value"
+	"gopkg.in/ini.v1"
+)
+
+const (
+	Name      = "ini"
+	Separator = "."
+)
+
+var _ config.Provider = (*Provider)(nil)
+
+func New(data *ini.File) *Provider {
+	return &Provider{
+		data: data,
+		resolve: func(path []string) (string, string) {
+			if len(path) == 1 {
+				return "", path[0]
+			}
+
+			return strings.Join(path[:len(path)-1], Separator), strings.ToUpper(path[len(path)-1])
+		},
+		name: Name,
+	}
+}
+
+type Provider struct {
+	data    *ini.File
+	resolve func(path []string) (string, string)
+	name    string
+}
+
+func (p *Provider) Name() string {
+	return p.name
+}
+
+func (p *Provider) Value(_ context.Context, path ...string) (config.Value, error) {
+	section, name := p.resolve(path)
+
+	iniSection, err := p.data.GetSection(section)
+	if err != nil {
+		return nil, fmt.Errorf("%w: %s: %w", config.ErrValueNotFound, p.Name(), err)
+	}
+
+	iniKey, err := iniSection.GetKey(name)
+	if err != nil {
+		return nil, fmt.Errorf("%w: %s: %w", config.ErrValueNotFound, p.Name(), err)
+	}
+
+	return value.JString(iniKey.String()), nil
+}

provider/ini/provider_test.go

@@ -0,0 +1,38 @@
+package ini_test
+
+import (
+	"embed"
+	"testing"
+	"time"
+
+	"gitoa.ru/go-4devs/config/provider/ini"
+	"gitoa.ru/go-4devs/config/test"
+	"gitoa.ru/go-4devs/config/test/require"
+	lib "gopkg.in/ini.v1"
+)
+
+//go:embed fixture/*
+var fixtures embed.FS
+
+func TestProvider(t *testing.T) {
+	t.Parallel()
+
+	data, derr := fixtures.ReadFile("fixture/config.ini")
+	require.NoError(t, derr)
+
+	file, err := lib.Load(data)
+	require.NoError(t, err)
+
+	read := []test.Read{
+		test.NewRead("To Do, In Progress, Done", "project", "PROJECT_BOARD_BASIC_KANBAN_TYPE"),
+		test.NewRead("markdown", "repository.editor", "PREVIEWABLE_FILE_MODES"),
+		test.NewRead("http://0.0.0.0:3000/", "server", "LOCAL_ROOT_URL"),
+		test.NewRead(20*time.Minute, "server", "LFS_HTTP_AUTH_EXPIRY"),
+		test.NewRead(5120, "repository.pull-request", "DEFAULT_MERGE_MESSAGE_SIZE"),
+		test.NewRead(true, "ui", "SHOW_USER_EMAIL"),
+		test.NewRead(false, "cors", "enabled"),
+	}
+
+	prov := ini.New(file)
+	test.Run(t, prov, read)
+}

provider/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/json/go.mod

@@ -0,0 +1,13 @@
+module gitoa.ru/go-4devs/config/provider/json
+
+go 1.23
+
+require (
+	github.com/tidwall/gjson v1.18.0
+	gitoa.ru/go-4devs/config v0.0.3
+)
+
+require (
+	github.com/tidwall/match v1.1.1 // indirect
+	github.com/tidwall/pretty v1.2.0 // indirect
+)

provider/json/go.sum

@@ -0,0 +1,10 @@
+github.com/tidwall/gjson v1.17.0 h1:/Jocvlh98kcTfpN2+JzGQWQcqrPQwDrVEMApx/M5ZwM=
+github.com/tidwall/gjson v1.17.0/go.mod h1:/wbyibRr2FHMks5tjHJ5F8dMZh3AcwJEMf5vlfC0lxk=
+github.com/tidwall/gjson v1.18.0 h1:FIDeeyB800efLX89e5a8Y0BNH+LOngJyGrIWxG2FKQY=
+github.com/tidwall/gjson v1.18.0/go.mod h1:/wbyibRr2FHMks5tjHJ5F8dMZh3AcwJEMf5vlfC0lxk=
+github.com/tidwall/match v1.1.1 h1:+Ho715JplO36QYgwN9PGYNhgZvoUSc9X2c80KVTi+GA=
+github.com/tidwall/match v1.1.1/go.mod h1:eRSPERbgtNPcGhD8UCthc6PmLEQXEWd3PRB5JTxsfmM=
+github.com/tidwall/pretty v1.2.0 h1:RWIZEg2iJ8/g6fDDYzMpobmaoGh5OLl4AXtGUGPcqCs=
+github.com/tidwall/pretty v1.2.0/go.mod h1:ITEVvHYasfjBbM0u2Pg8T2nJnzm8xPwvNhhsoaGGjNU=
+gitoa.ru/go-4devs/config v0.0.3 h1:+ecwDQj4fneJCh2uLNNAonm4cUJdGmlfxUsFhQRI9Ko=
+gitoa.ru/go-4devs/config v0.0.3/go.mod h1:UINWnObZA0nLiJro+TtavUBBvN0cSt17aRHOk20pP74=

provider/json/provider.go

@@ -0,0 +1,66 @@
+package json //nolint:revive
+
+import (
+	"context"
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+
+	"github.com/tidwall/gjson"
+	"gitoa.ru/go-4devs/config"
+	"gitoa.ru/go-4devs/config/value"
+)
+
+const (
+	Name      = "json"
+	Separator = "."
+)
+
+var _ config.Provider = (*Provider)(nil)
+
+func New(json []byte, opts ...Option) *Provider {
+	provider := Provider{
+		key: func(s ...string) string {
+			return strings.Join(s, Separator)
+		},
+		data: json,
+		name: Name,
+	}
+
+	for _, opt := range opts {
+		opt(&provider)
+	}
+
+	return &provider
+}
+
+func NewFile(path string, opts ...Option) (*Provider, error) {
+	file, err := os.ReadFile(filepath.Clean(path))
+	if err != nil {
+		return nil, fmt.Errorf("%w: unable to read config file %#q: file not found or unreadable", err, path)
+	}
+
+	return New(file, opts...), nil
+}
+
+type Option func(*Provider)
+
+type Provider struct {
+	data []byte
+	key  func(...string) string
+	name string
+}
+
+func (p *Provider) Name() string {
+	return p.name
+}
+
+func (p *Provider) Value(_ context.Context, path ...string) (config.Value, error) {
+	key := p.key(path...)
+	if val := gjson.GetBytes(p.data, key); val.Exists() {
+		return value.JString(val.String()), nil
+	}
+
+	return nil, fmt.Errorf("%v:%w", p.Name(), config.ErrValueNotFound)
+}

provider/json/provider_example_test.go

@@ -0,0 +1,55 @@
+package json_test
+
+import (
+	"context"
+	"fmt"
+	"log"
+
+	"gitoa.ru/go-4devs/config"
+	"gitoa.ru/go-4devs/config/provider/json"
+	"gitoa.ru/go-4devs/config/test"
+)
+
+func ExampleClient_Value() {
+	ctx := context.Background()
+
+	// read json config
+	jsonConfig, jerr := fixture.ReadFile("fixture/config.json")
+	if jerr != nil {
+		log.Printf("failed load file:%v", jerr)
+
+		return
+	}
+
+	config, err := config.New(
+		json.New(jsonConfig),
+	)
+	if err != nil {
+		log.Print(err)
+
+		return
+	}
+
+	title, err := config.Value(ctx, "app.name.title")
+	if err != nil {
+		log.Print("app.name.title", err)
+
+		return
+	}
+
+	cfgValue, err := config.Value(ctx, "cfg")
+	if err != nil {
+		log.Print("cfg ", err)
+
+		return
+	}
+
+	cfg := test.Config{}
+	_ = cfgValue.Unmarshal(&cfg)
+
+	fmt.Printf("title from json: %v\n", title.String())
+	fmt.Printf("struct from json: %+v\n", cfg)
+	// Output:
+	// title from json: config title
+	// struct from json: {Duration:21m0s Enabled:true}
+}

provider/json/provider_test.go

@@ -0,0 +1,33 @@
+package json_test
+
+import (
+	"embed"
+	"testing"
+	"time"
+
+	"gitoa.ru/go-4devs/config/provider/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 := json.New(js)
+	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/memory/def.go

@@ -0,0 +1,44 @@
+package memory
+
+import (
+	"context"
+	"fmt"
+
+	"gitoa.ru/go-4devs/config"
+	"gitoa.ru/go-4devs/config/definition/option"
+)
+
+const NameDefault = "default"
+
+var _ config.BindProvider = (*Default)(nil)
+
+type Default struct {
+	data Map
+	name string
+}
+
+func (a *Default) Value(ctx context.Context, key ...string) (config.Value, error) {
+	if v, err := a.data.Value(ctx, key...); err == nil {
+		return v, nil
+	}
+
+	return nil, fmt.Errorf("%w", config.ErrNotFound)
+}
+
+func (a *Default) Bind(_ context.Context, def config.Variables) error {
+	for _, opt := range def.Variables() {
+		if data, ok := option.DataDefaut(opt); ok {
+			a.data.SetOption(data, opt.Key()...)
+		}
+	}
+
+	return nil
+}
+
+func (a *Default) Name() string {
+	if a.name != "" {
+		return a.name
+	}
+
+	return NameDefault
+}

provider/memory/map.go

@@ -0,0 +1,92 @@
+package memory
+
+import (
+	"context"
+	"fmt"
+	"sync"
+
+	"gitoa.ru/go-4devs/config"
+	"gitoa.ru/go-4devs/config/key"
+	"gitoa.ru/go-4devs/config/value"
+)
+
+const NameMap = "map"
+
+var _ config.BindProvider = (*Map)(nil)
+
+type Map struct {
+	mu   sync.Mutex
+	vals []config.Value
+	idx  key.Map
+	name string
+}
+
+func (m *Map) Len() int {
+	return len(m.vals)
+}
+
+func (m *Map) Value(_ context.Context, key ...string) (config.Value, error) {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+
+	idx, ok := m.idx.Index(key)
+	if !ok {
+		return nil, fmt.Errorf("%w", config.ErrNotFound)
+	}
+
+	val := m.vals[idx]
+
+	return val, nil
+}
+
+func (m *Map) Bind(_ context.Context, _ config.Variables) error {
+	return nil
+}
+
+func (m *Map) Name() string {
+	if m.name != "" {
+		return m.name
+	}
+
+	return NameMap
+}
+
+func (m *Map) HasOption(key ...string) bool {
+	_, ok := m.idx.Index(key)
+
+	return ok
+}
+
+func (m *Map) SetOption(val any, key ...string) {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+
+	if id, ok := m.idx.Index(key); ok {
+		m.vals[id] = value.New(val)
+
+		return
+	}
+
+	m.idx.Add(len(m.vals), key)
+	m.vals = append(m.vals, value.New(val))
+}
+
+func (m *Map) AppendOption(val string, keys ...string) error {
+	id, ok := m.idx.Index(keys)
+	if !ok {
+		data := value.Strings{val}
+
+		m.SetOption(data, keys...)
+
+		return nil
+	}
+
+	old, tok := m.vals[id].(value.Strings)
+	if !tok {
+		return fmt.Errorf("%w:%T", config.ErrWrongType, m.vals[id])
+	}
+
+	m.SetOption(old.Append(val), keys...)
+
+	return nil
+}

provider/memory/validate.go

@@ -0,0 +1,45 @@
+package memory
+
+import (
+	"context"
+
+	"gitoa.ru/go-4devs/config"
+	"gitoa.ru/go-4devs/config/definition/option"
+	"gitoa.ru/go-4devs/config/validator"
+	"gitoa.ru/go-4devs/config/value"
+)
+
+var _ config.BindProvider = (*Map)(nil)
+
+func Valid(in config.Provider) Validate {
+	return Validate{
+		Provider: in,
+		name:     "",
+	}
+}
+
+type Validate struct {
+	config.Provider
+
+	name string
+}
+
+func (a Validate) Bind(ctx context.Context, def config.Variables) error {
+	for _, opt := range def.Variables() {
+		if val, err := a.Value(ctx, opt.Key()...); err != nil && !value.IsEmpty(val) {
+			if err := validator.Validate(opt.Key(), opt, val); err != nil {
+				return option.Err(err, opt.Key())
+			}
+		}
+	}
+
+	return nil
+}
+
+func (a Validate) Name() string {
+	if a.name != "" {
+		return a.name
+	}
+
+	return a.Provider.Name()
+}

provider/toml/fixture/config.toml

@@ -0,0 +1,31 @@
+title = "TOML Example"
+
+[owner]
+name = "Tom Preston-Werner"
+dob = 1979-05-27T07:32:00-08:00 # First class dates
+
+[database]
+server = "192.168.1.1"
+ports = [ 8001, 8001, 8002 ]
+connection_max = 5000
+enabled = true
+
+[servers]
+
+  # Indentation (tabs and/or spaces) is allowed but not required
+  [servers.alpha]
+  ip = "10.0.0.1"
+  dc = "eqdc10"
+
+  [servers.beta]
+  ip = "10.0.0.2"
+  dc = "eqdc10"
+
+[clients]
+data = [ ["gamma", "delta"], [1, 2] ]
+
+# Line breaks are OK when inside arrays
+hosts = [
+  "alpha",
+  "omega"
+]

provider/toml/go.mod

@@ -0,0 +1,8 @@
+module gitoa.ru/go-4devs/config/provider/toml
+
+go 1.23
+
+require (
+	github.com/pelletier/go-toml/v2 v2.2.4
+	gitoa.ru/go-4devs/config v0.0.5
+)