add config definition

Reviewed-on: #9

.drone.yml

@@ -2,10 +2,6 @@
 kind: pipeline
 name: default
 
-environment:
-  VAULT_DEV_LISTEN_ADDRESS: http://vault:8200
-  VAULT_DEV_ROOT_TOKEN_ID: dev
-
 steps:
 - name: test 
   image: golang
@@ -119,3 +115,51 @@ steps:
   - cd provider/etcd
   - golangci-lint run
 
+---
+kind: pipeline
+type: docker
+name: vault
+
+environment:
+  VAULT_DEV_LISTEN_ADDRESS: http://vault:8200
+  VAULT_DEV_ROOT_TOKEN_ID: dev
+
+services:
+  - name: vault
+    image: vault:1.13.3
+    environment:
+      VAULT_DEV_ROOT_TOKEN_ID: dev
+      VAULT_DEV_LISTEN_ADDRESS: 0.0.0.0:8200
+
+steps:
+- name: test 
+  image: golang
+  failure: ignore # runtime/cgo: pthread_create failed: Operation not permitted
+  commands:
+  - cd provider/vault
+  - go test ./... 
+
+- name: golangci-lint
+  image: golangci/golangci-lint:v1.55
+  commands:
+  - cd provider/vault
+  - golangci-lint run
+
+---
+kind: pipeline
+type: docker
+name: definition
+
+steps:
+- name: test 
+  image: golang
+  commands:
+  - cd definition
+  - go test ./... 
+
+- name: golangci-lint
+  image: golangci/golangci-lint:v1.55
+  commands:
+  - cd definition
+  - golangci-lint run
+

.golangci.yml

@@ -24,6 +24,13 @@ linters-settings:
       locale: US  
     varnamelen:
       min-name-length: 2
+      ignore-decls:
+        - w io.Writer
+        - t testing.T
+        - e error
+        - i int
+        - b bytes.Buffer
+        - h Handle
 
 linters:
     enable-all: true

definition/defenition.go

@@ -0,0 +1,29 @@
+package definition
+
+import (
+	"fmt"
+)
+
+func New() Definition {
+	return Definition{}
+}
+
+type Definition struct {
+	options Options
+}
+
+func (d *Definition) Add(opts ...Option) *Definition {
+	d.options = append(d.options, opts...)
+
+	return d
+}
+
+func (d *Definition) View(handle func(Option) error) error {
+	for idx, opt := range d.options {
+		if err := handle(opt); err != nil {
+			return fmt.Errorf("%s[%d]:%w", opt.Kind(), idx, err)
+		}
+	}
+
+	return nil
+}

definition/generate/generator.go

@@ -0,0 +1,70 @@
+package generate
+
+import (
+	"fmt"
+	"io"
+
+	"gitoa.ru/go-4devs/config/definition"
+)
+
+type Generator struct {
+	pkg string
+	ViewOption
+	Imp           Imports
+	errs          []error
+	defaultErrors []string
+}
+
+func (g Generator) Pkg() string {
+	return g.pkg
+}
+
+func (g Generator) Imports() []Import {
+	return g.Imp.Imports()
+}
+
+func (g Generator) Handle(w io.Writer, data Handler, opt definition.Option) error {
+	handle := get(opt.Kind())
+
+	return handle(w, data, opt)
+}
+
+func (g Generator) StructName() string {
+	return FuncName(g.Prefix + "_" + g.Struct + "_" + g.Suffix)
+}
+
+func (g Generator) Options() ViewOption {
+	return g.ViewOption
+}
+
+func (g Generator) Keys() []string {
+	return nil
+}
+
+func (g Generator) DefaultErrors() []string {
+	if len(g.defaultErrors) > 0 {
+		return g.defaultErrors
+	}
+
+	if len(g.ViewOption.Errors.Default) > 0 {
+		g.Imp.Adds("errors")
+	}
+
+	g.defaultErrors = make([]string, len(g.ViewOption.Errors.Default))
+	for idx, name := range g.ViewOption.Errors.Default {
+		short, err := g.AddType(name)
+		if err != nil {
+			g.errs = append(g.errs, fmt.Errorf("add default error[%d]:%w", idx, err))
+
+			return nil
+		}
+
+		g.defaultErrors[idx] = short
+	}
+
+	return g.defaultErrors
+}
+
+func (g *Generator) AddType(pkg string) (string, error) {
+	return g.Imp.AddType(pkg)
+}

definition/generate/helpers.go

@@ -0,0 +1,18 @@
+package generate
+
+import (
+	"errors"
+
+	"github.com/iancoleman/strcase"
+)
+
+var (
+	ErrNotFound     = errors.New("not found")
+	ErrAlreadyExist = errors.New("already exist")
+	ErrWrongType    = errors.New("wrong type")
+	ErrWrongFormat  = errors.New("wrong format")
+)
+
+func FuncName(in string) string {
+	return strcase.ToCamel(in)
+}

definition/generate/imports.go

@@ -0,0 +1,89 @@
+package generate
+
+import (
+	"fmt"
+	"strconv"
+	"strings"
+)
+
+func NewImports() Imports {
+	return Imports{
+		data: make(map[string]string),
+	}
+}
+
+type Imports struct {
+	data map[string]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", ErrWrongFormat)
+	}
+
+	imp := i.Add(fullType[:idx])
+
+	return imp.Alias + fullType[idx:], nil
+}
+
+func (i *Imports) Adds(pkgs ...string) {
+	for _, pkg := range pkgs {
+		i.Add(pkg)
+	}
+}
+
+func (i *Imports) Add(pkg string) Import {
+	alias := pkg
+
+	if idx := strings.LastIndexByte(pkg, '/'); idx != -1 {
+		alias = 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/run.go

@@ -0,0 +1,39 @@
+package generate
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+
+	"gitoa.ru/go-4devs/config/definition"
+)
+
+func Run(w io.Writer, pkgName string, defs definition.Definition, viewOpt ViewOption) error {
+	gen := Generator{
+		pkg:        pkgName,
+		ViewOption: viewOpt,
+		Imp:        NewImports(),
+	}
+
+	gen.Imp.Adds("gitoa.ru/go-4devs/config", "fmt", "context")
+
+	var view bytes.Buffer
+
+	err := defs.View(func(o definition.Option) error {
+		return gen.Handle(&view, &gen, o)
+	})
+	if err != nil {
+		return fmt.Errorf("render options:%w", err)
+	}
+
+	if err := tpl.Execute(w, gen); err != nil {
+		return fmt.Errorf("render base:%w", err)
+	}
+
+	_, cerr := io.Copy(w, &view)
+	if cerr != nil {
+		return fmt.Errorf("copy error:%w", cerr)
+	}
+
+	return nil
+}

definition/generate/template.go

@@ -0,0 +1,43 @@
+package generate
+
+import "text/template"
+
+//nolint:gochecknoglobals
+var (
+	tpl          = template.Must(template.New("tpls").Parse(baseTemplate))
+	baseTemplate = `// Code generated gitoa.ru/go-4devs/config DO NOT EDIT.
+package {{.Pkg}}
+
+import (
+    {{range .Imports}}
+    {{- .Alias }}"{{ .Package }}"
+    {{end}}
+)
+
+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/view.go

@@ -0,0 +1,63 @@
+package generate
+
+import (
+	"fmt"
+	"io"
+	"sync"
+
+	"gitoa.ru/go-4devs/config/definition"
+)
+
+//nolint:gochecknoglobals
+var handlers = sync.Map{}
+
+func Add(kind string, h Handle) error {
+	_, ok := handlers.Load(kind)
+	if ok {
+		return fmt.Errorf("kind %v: %w", kind, ErrAlreadyExist)
+	}
+
+	handlers.Store(kind, h)
+
+	return nil
+}
+
+//nolint:forcetypeassert
+func get(kind string) Handle {
+	handler, ok := handlers.Load(kind)
+	if !ok {
+		return func(w io.Writer, h Handler, o definition.Option) error {
+			return fmt.Errorf("handler by %v:%w", kind, ErrNotFound)
+		}
+	}
+
+	return handler.(Handle)
+}
+
+func MustAdd(kind string, h Handle) {
+	if err := Add(kind, h); err != nil {
+		panic(err)
+	}
+}
+
+type Handle func(io.Writer, Handler, definition.Option) error
+
+type Handler interface {
+	StructName() string
+	Handle(w io.Writer, handler Handler, opt definition.Option) error
+	Options() ViewOption
+	Keys() []string
+	AddType(fullName string) (string, error)
+	DefaultErrors() []string
+}
+
+type ViewOption struct {
+	Prefix, Suffix string
+	Context        bool
+	Struct         string
+	Errors         ViewErrors
+}
+
+type ViewErrors struct {
+	Default []string
+}

definition/go.mod

@@ -0,0 +1,5 @@
+module gitoa.ru/go-4devs/config/definition
+
+go 1.21.5
+
+require github.com/iancoleman/strcase v0.3.0

definition/go.sum

@@ -0,0 +1,2 @@
+github.com/iancoleman/strcase v0.3.0 h1:nTXanmYxhfFAMjZL34Ov6gkzEsSJZ5DbhxWjvSASxEI=
+github.com/iancoleman/strcase v0.3.0/go.mod h1:iwCmte+B7n89clKwxIoIXy/HfoL7AsD47ZCWhYzw7ho=

definition/group/group.go

@@ -0,0 +1,27 @@
+package group
+
+import (
+	"gitoa.ru/go-4devs/config/definition"
+)
+
+const Kind = "group"
+
+var _ definition.Option = Group{}
+
+func New(name, desc string, opts ...definition.Option) Group {
+	return Group{
+		Name:        name,
+		Description: desc,
+		Options:     opts,
+	}
+}
+
+type Group struct {
+	Options     definition.Options
+	Name        string
+	Description string
+}
+
+func (o Group) Kind() string {
+	return Kind
+}

definition/group/view.go

@@ -0,0 +1,88 @@
+package group
+
+import (
+	"fmt"
+	"io"
+	"text/template"
+
+	"gitoa.ru/go-4devs/config/definition"
+	"gitoa.ru/go-4devs/config/definition/generate"
+)
+
+//nolint:gochecknoinits
+func init() {
+	generate.MustAdd(Kind, handle)
+}
+
+func handle(w io.Writer, data generate.Handler, option definition.Option) error {
+	group, ok := option.(Group)
+	if !ok {
+		return fmt.Errorf("%w:%T", generate.ErrWrongType, option)
+	}
+
+	viewData := View{
+		Group:      group,
+		ParentName: data.StructName(),
+		ViewOption: data.Options(),
+	}
+
+	err := tpl.Execute(w, viewData)
+	if err != nil {
+		return fmt.Errorf("render group:%w", err)
+	}
+
+	childData := ChildData{
+		Handler:    data,
+		structName: viewData.StructName(),
+		keys:       append(data.Keys(), group.Name),
+	}
+	for idx, child := range group.Options {
+		if cerr := data.Handle(w, childData, child); cerr != nil {
+			return fmt.Errorf("render group child[%d]:%w", idx, cerr)
+		}
+	}
+
+	return nil
+}
+
+type ChildData struct {
+	generate.Handler
+	structName string
+	keys       []string
+}
+
+func (c ChildData) StructName() string {
+	return c.structName
+}
+
+func (c ChildData) Keys() []string {
+	return c.keys
+}
+
+type View struct {
+	Group
+	ParentName string
+	generate.ViewOption
+}
+
+func (v View) FuncName() string {
+	return generate.FuncName(v.Name)
+}
+
+func (v View) StructName() string {
+	return generate.FuncName(v.Prefix + v.Name + v.Suffix)
+}
+
+//nolint:gochecknoglobals
+var (
+	tpl           = template.Must(template.New("tpls").Parse(gpoupTemplate))
+	gpoupTemplate = `type {{.StructName}} struct {
+    {{.ParentName}}
+}
+
+// {{.FuncName}} {{.Description}}.
+func (i {{.ParentName}}) {{.FuncName}}() {{.StructName}} {
+	return {{.StructName}}{i}
+}
+`
+)

definition/option.go

@@ -0,0 +1,27 @@
+package definition
+
+type Option interface {
+	Kind() string
+}
+
+type Options []Option
+
+func (s Options) Len() int      { return len(s) }
+func (s Options) Swap(i, j int) { s[i], s[j] = s[j], s[i] }
+
+type Params []Param
+
+func (p Params) Get(name string) (any, bool) {
+	for _, param := range p {
+		if param.Name == name {
+			return param.Value, true
+		}
+	}
+
+	return nil, false
+}
+
+type Param struct {
+	Name  string
+	Value any
+}

definition/option/option.go

@@ -0,0 +1,100 @@
+package option
+
+import (
+	"gitoa.ru/go-4devs/config/definition"
+)
+
+var _ definition.Option = Option{}
+
+const (
+	Kind = "option"
+)
+
+const (
+	TypeString   = "string"
+	TypeInt      = "int"
+	TypeInt64    = "int64"
+	TypeUint     = "uint"
+	TypeUint64   = "uint64"
+	TypeFloat64  = "float64"
+	TypeBool     = "bool"
+	TypeTime     = "time.Time"
+	TypeDuration = "time.Duration"
+)
+
+func Default(v any) func(*Option) {
+	return func(o *Option) {
+		o.Default = v
+	}
+}
+
+func New(name, desc string, vtype any, opts ...func(*Option)) Option {
+	option := Option{
+		Name:        name,
+		Description: desc,
+		Type:        vtype,
+	}
+
+	for _, opt := range opts {
+		opt(&option)
+	}
+
+	return option
+}
+
+type Option struct {
+	Name        string
+	Description string
+	Type        any
+	Default     any
+	Params      definition.Params
+}
+
+func (o Option) WithParams(params ...definition.Param) Option {
+	return Option{
+		Name:        o.Name,
+		Description: o.Description,
+		Type:        o.Type,
+		Params:      append(params, o.Params...),
+	}
+}
+
+func (o Option) Kind() string {
+	return Kind
+}
+
+func Time(name, desc string, opts ...func(*Option)) Option {
+	return New(name, desc, TypeTime, opts...)
+}
+
+func Duration(name, desc string, opts ...func(*Option)) Option {
+	return New(name, desc, TypeDuration, opts...)
+}
+
+func String(name, desc string, opts ...func(*Option)) Option {
+	return New(name, desc, TypeString, opts...)
+}
+
+func Int(name, desc string, opts ...func(*Option)) Option {
+	return New(name, desc, TypeInt, opts...)
+}
+
+func Int64(name, desc string, opts ...func(*Option)) Option {
+	return New(name, desc, TypeInt64, opts...)
+}
+
+func Uint(name, desc string, opts ...func(*Option)) Option {
+	return New(name, desc, TypeUint, opts...)
+}
+
+func Uint64(name, desc string, opts ...func(*Option)) Option {
+	return New(name, desc, TypeUint64, opts...)
+}
+
+func Float64(name, desc string, opts ...func(*Option)) Option {
+	return New(name, desc, TypeFloat64, opts...)
+}
+
+func Bool(name, desc string, opts ...func(*Option)) Option {
+	return New(name, desc, TypeBool, opts...)
+}

definition/option/tpl/option.tmpl

@@ -0,0 +1,33 @@
+// read{{.FuncName}} {{.Description}}.
+func (i {{.StructName}}) read{{.FuncName}}(ctx context.Context) (v {{.Type}},e error) {
+	val, err := i.Value(ctx, {{ .ParentKeys }}"{{ .Name }}")
+	if err != nil {
+        {{if .HasDefault}}
+        {{$default := .Default}}
+        {{range .DefaultErrors}}
+        if errors.Is(err,{{.}}){
+            return {{$default}}
+		}
+        {{end}}
+        {{end}}
+        return v, fmt.Errorf("read {{.Keys}}:%w",err)
+	}
+
+	{{.Parse "val" "v" .Keys }}
+}
+
+// Read{{.FuncName}} {{.Description}}.
+func (i {{.StructName}}) Read{{.FuncName}}(ctx context.Context) ({{.Type}}, error) {
+    return i.read{{.FuncName}}(ctx)
+}
+
+// {{.FuncName}} {{.Description}}.
+func (i {{.StructName}}) {{.FuncName}}({{if .Context}} ctx context.Context {{end}}) {{.Type}} {
+    {{if not .Context}} ctx := context.Background() {{end}}
+	val, err := i.read{{.FuncName}}(ctx)
+	if err != nil {
+		i.log(ctx, "get {{.Keys}}: %v", err)
+	}
+
+	return val
+}

definition/option/tpl/parse.tmpl

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

definition/option/tpl/unmarshal_json.tmpl

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

definition/option/tpl/unmarshal_text.tmpl

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

definition/option/view.go

@@ -0,0 +1,235 @@
+package option
+
+import (
+	"bytes"
+	"embed"
+	"encoding"
+	"encoding/json"
+	"fmt"
+	"io"
+	"reflect"
+	"strings"
+	"text/template"
+	"time"
+
+	"gitoa.ru/go-4devs/config/definition"
+	"gitoa.ru/go-4devs/config/definition/generate"
+)
+
+//go:embed tpl/*
+var tpls embed.FS
+
+//nolint:gochecknoglobals
+var tpl = template.Must(template.New("tpls").ParseFS(tpls, "tpl/*.tmpl"))
+
+//nolint:gochecknoinits
+func init() {
+	generate.MustAdd(Kind, Handle(tpl.Lookup("option.tmpl")))
+}
+
+func Handle(tpl *template.Template) generate.Handle {
+	return func(w io.Writer, h generate.Handler, o definition.Option) error {
+		opt, _ := o.(Option)
+		if err := tpl.Execute(w, View{Option: opt, Handler: h}); err != nil {
+			return fmt.Errorf("option tpl:%w", err)
+		}
+
+		return nil
+	}
+}
+
+type View struct {
+	Option
+	generate.Handler
+}
+
+func (v View) Context() bool {
+	return v.Options().Context
+}
+
+func (v View) FuncName() string {
+	if funcName, ok := v.Option.Params.Get(ViewParamFunctName); ok {
+		name, _ := funcName.(string)
+
+		return name
+	}
+
+	return generate.FuncName(v.Name)
+}
+
+func (v View) Description() string {
+	if desc, ok := v.Option.Params.Get(ViewParamDescription); ok {
+		description, _ := desc.(string)
+
+		return description
+	}
+
+	return v.Option.Description
+}
+
+func (v View) Default() string {
+	switch data := v.Option.Default.(type) {
+	case time.Time:
+		return fmt.Sprintf("time.Parse(%q,time.RFC3339Nano)", data.Format(time.RFC3339Nano))
+	case time.Duration:
+		return fmt.Sprintf("time.ParseDuration(%q)", data)
+	default:
+		return fmt.Sprintf("%#v, nil", data)
+	}
+}
+
+func (v View) HasDefault() bool {
+	return v.Option.Default != nil
+}
+
+func (v View) ParentKeys() string {
+	if len(v.Handler.Keys()) > 0 {
+		return `"` + strings.Join(v.Handler.Keys(), `","`) + `",`
+	}
+
+	return ""
+}
+
+func (v View) Type() string {
+	slice := ""
+
+	if vtype, ok := v.Option.Type.(string); ok {
+		if strings.Contains(vtype, ".") {
+			if name, err := v.AddType(vtype); err == nil {
+				return slice + name
+			}
+		}
+
+		return vtype
+	}
+
+	rtype := reflect.TypeOf(v.Option.Type)
+
+	if rtype.PkgPath() == "" {
+		return rtype.String()
+	}
+
+	if rtype.Kind() == reflect.Slice {
+		slice = "[]"
+	}
+
+	short, err := v.AddType(rtype.PkgPath() + "." + rtype.Name())
+	if err != nil {
+		return err.Error()
+	}
+
+	return slice + short
+}
+
+func (v View) FuncType() string {
+	return generate.FuncName(v.Type())
+}
+
+func (v View) Parse(valName string, value string, keys []string) string {
+	h := parser(v.Option.Type)
+
+	data, err := h(ParseData{
+		Value:   value,
+		ValName: valName,
+		Keys:    keys,
+		View:    v,
+	})
+	if err != nil {
+		return err.Error()
+	}
+
+	return data
+}
+
+//nolint:gochecknoglobals,unparam
+var parses = map[string]func(data ParseData) (string, error){
+	typesIntreface[0].Name(): func(data ParseData) (string, error) {
+		var b bytes.Buffer
+
+		err := tpl.ExecuteTemplate(&b, "unmarshal_text.tmpl", data)
+		if err != nil {
+			return "", fmt.Errorf("execute unmarshal text:%w", err)
+		}
+
+		return b.String(), nil
+	},
+	typesIntreface[1].Name(): func(data ParseData) (string, error) {
+		var b bytes.Buffer
+
+		err := tpl.ExecuteTemplate(&b, "unmarshal_json.tmpl", data)
+		if err != nil {
+			return "", fmt.Errorf("execute unmarshal json:%w", err)
+		}
+
+		return b.String(), nil
+	},
+	TypeInt:     internal,
+	TypeInt64:   internal,
+	TypeBool:    internal,
+	TypeString:  internal,
+	TypeFloat64: internal,
+	TypeUint:    internal,
+	TypeUint64:  internal,
+	"time.Duration": func(data ParseData) (string, error) {
+		return fmt.Sprintf("return %s.ParseDuration()", data.ValName), nil
+	},
+	"time.Time": func(data ParseData) (string, error) {
+		return fmt.Sprintf("return %s.ParseTime()", data.ValName), nil
+	},
+	"any": func(data ParseData) (string, error) {
+		return fmt.Sprintf("return %[2]s, %[1]s.Unmarshal(&%[2]s)", data.ValName, data.Value), nil
+	},
+}
+
+func internal(data ParseData) (string, error) {
+	var b bytes.Buffer
+
+	err := tpl.ExecuteTemplate(&b, "parse.tmpl", data)
+	if err != nil {
+		return "", fmt.Errorf("execute parse.tmpl:%w", err)
+	}
+
+	return b.String(), nil
+}
+
+//nolint:gochecknoglobals
+var typesIntreface = [...]reflect.Type{
+	reflect.TypeOf((*encoding.TextUnmarshaler)(nil)).Elem(),
+	reflect.TypeOf((*json.Unmarshaler)(nil)).Elem(),
+}
+
+func parser(data any) func(ParseData) (string, error) {
+	vtype := reflect.TypeOf(data)
+	name := vtype.Name()
+
+	if v, ok := data.(string); ok {
+		name = v
+	}
+
+	if vtype.Kind() == reflect.Slice {
+		return parses["any"]
+	}
+
+	if h, ok := parses[name]; ok {
+		return h
+	}
+
+	for _, extypes := range typesIntreface {
+		if vtype.Implements(extypes) {
+			return parses[extypes.Name()]
+		}
+
+		if vtype.Kind() != reflect.Ptr && reflect.PointerTo(vtype).Implements(extypes) {
+			return parses[extypes.Name()]
+		}
+	}
+
+	return parses["any"]
+}
+
+type ParseData struct {
+	Value   string
+	ValName string
+	Keys    []string
+	View
+}

definition/option/view_params.go

@@ -0,0 +1,6 @@
+package option
+
+const (
+	ViewParamFunctName   = "view.funcName"
+	ViewParamDescription = "view.description"
+)

definition/proto/proto.go

@@ -0,0 +1,27 @@
+package proto
+
+import (
+	"gitoa.ru/go-4devs/config/definition"
+)
+
+const Kind = "proto"
+
+func New(name, desc string, opt definition.Option) Proto {
+	pr := Proto{
+		Name:        name,
+		Description: desc,
+		Option:      opt,
+	}
+
+	return pr
+}
+
+type Proto struct {
+	Name        string
+	Description string
+	Option      definition.Option
+}
+
+func (p Proto) Kind() string {
+	return Kind
+}

definition/proto/view.go

@@ -0,0 +1,80 @@
+package proto
+
+import (
+	"fmt"
+	"io"
+	"strings"
+	"text/template"
+
+	"gitoa.ru/go-4devs/config/definition"
+	"gitoa.ru/go-4devs/config/definition/generate"
+	"gitoa.ru/go-4devs/config/definition/option"
+)
+
+//nolint:gochecknoinits
+func init() {
+	generate.MustAdd(Kind, handle)
+}
+
+func handle(w io.Writer, data generate.Handler, opt definition.Option) error {
+	proto, ok := opt.(Proto)
+	if !ok {
+		return fmt.Errorf("%w:%T", generate.ErrWrongType, opt)
+	}
+
+	if viewOpt, ok := proto.Option.(option.Option); ok {
+		viewOpt = viewOpt.WithParams(
+			definition.Param{
+				Name:  option.ViewParamFunctName,
+				Value: generate.FuncName(proto.Name) + generate.FuncName(viewOpt.Name),
+			},
+			definition.Param{
+				Name:  option.ViewParamDescription,
+				Value: proto.Description + " " + viewOpt.Description,
+			},
+		)
+
+		return option.Handle(tpl)(w, data, viewOpt)
+	}
+
+	return fmt.Errorf("%w:%T", generate.ErrWrongType, opt)
+}
+
+//nolint:gochecknoglobals
+var (
+	tpl            = template.Must(template.New("tpls").Funcs(template.FuncMap{"join": strings.Join}).Parse(templateOption))
+	templateOption = `// read{{.FuncName}} {{.Description}}.
+func (i {{.StructName}}) read{{.FuncName}}(ctx context.Context, key string) (v {{.Type}},e error) {
+	val, err := i.Value(ctx, {{ .ParentKeys }} key, "{{.Name}}")
+	if err != nil {
+        {{if .HasDefault}}
+        {{$default := .Default}}
+        {{range .DefaultErrors}}
+        if errors.Is(err,{{.}}){
+            return {{$default}}
+		}
+        {{end}}
+        {{end}}
+        return v, fmt.Errorf("read {{.Keys}}:%w",err)
+	}
+
+	{{.Parse "val" "v" .Keys }}
+}
+
+// Read{{.FuncName}} {{.Description}}.
+func (i {{.StructName}}) Read{{.FuncName}}(ctx context.Context, key string) ({{.Type}}, error) {
+    return i.read{{.FuncName}}(ctx, key)
+}
+
+// {{.FuncName}} {{.Description}}.
+func (i {{.StructName}}) {{.FuncName}}({{if .Context}} ctx context.Context, {{end}} key string) {{.Type}} {
+    {{if not .Context}} ctx := context.Background() {{end}}
+	val, err := i.read{{.FuncName}}(ctx, key)
+	if err != nil {
+		i.log(ctx, "get {{.Keys}}: %v", err)
+	}
+
+	return val
+}
+`
+)

provider/vault/go.mod

@@ -0,0 +1,29 @@
+module gitoa.ru/go-4devs/config/provider/vault
+
+go 1.21
+
+require (
+	github.com/hashicorp/vault/api v1.11.0
+	gitoa.ru/go-4devs/config v0.0.2
+)
+
+require (
+	github.com/cenkalti/backoff/v3 v3.0.0 // indirect
+	github.com/go-jose/go-jose/v3 v3.0.1 // indirect
+	github.com/hashicorp/errwrap v1.1.0 // indirect
+	github.com/hashicorp/go-cleanhttp v0.5.2 // indirect
+	github.com/hashicorp/go-multierror v1.1.1 // indirect
+	github.com/hashicorp/go-retryablehttp v0.6.6 // indirect
+	github.com/hashicorp/go-rootcerts v1.0.2 // indirect
+	github.com/hashicorp/go-secure-stdlib/parseutil v0.1.6 // indirect
+	github.com/hashicorp/go-secure-stdlib/strutil v0.1.2 // indirect
+	github.com/hashicorp/go-sockaddr v1.0.2 // indirect
+	github.com/hashicorp/hcl v1.0.0 // indirect
+	github.com/mitchellh/go-homedir v1.1.0 // indirect
+	github.com/mitchellh/mapstructure v1.5.0 // indirect
+	github.com/ryanuber/go-glob v1.0.0 // indirect
+	golang.org/x/crypto v0.17.0 // indirect
+	golang.org/x/net v0.17.0 // indirect
+	golang.org/x/text v0.14.0 // indirect
+	golang.org/x/time v0.0.0-20200416051211-89c76fbcd5d1 // indirect
+)

provider/vault/go.sum

@@ -0,0 +1,92 @@
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+github.com/bgentry/speakeasy v0.1.0/go.mod h1:+zsyZBPWlz7T6j88CTgSN5bM796AkVf0kBD4zp0CCIs=
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+golang.org/x/time v0.0.0-20200416051211-89c76fbcd5d1/go.mod h1:tRJNPiyCQ0inRvYxbN9jk5I+vvW/OXSQhTDSoE431IQ=
+golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=

provider/vault/provider.go

@@ -0,0 +1,120 @@
+package vault
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"strings"
+
+	"github.com/hashicorp/vault/api"
+	"gitoa.ru/go-4devs/config"
+	"gitoa.ru/go-4devs/config/value"
+)
+
+const (
+	Name      = "vault"
+	Separator = "/"
+	Prefix    = "secret/data/"
+	ValueName = "value"
+)
+
+var _ config.Provider = (*Provider)(nil)
+
+type SecretOption func(*Provider)
+
+func WithSecretResolve(f func(key []string) (string, string)) SecretOption {
+	return func(s *Provider) { s.resolve = f }
+}
+
+func New(namespace, appName string, client *api.Client, opts ...SecretOption) *Provider {
+	prov := Provider{
+		client: client,
+		resolve: func(key []string) (string, string) {
+			keysLen := len(key)
+			if keysLen == 1 {
+				return "", key[0]
+			}
+
+			return strings.Join(key[:keysLen-1], Separator), key[keysLen-1]
+		},
+		name:   Name,
+		prefix: Prefix + namespace + Separator + appName,
+	}
+
+	for _, opt := range opts {
+		opt(&prov)
+	}
+
+	return &prov
+}
+
+type Provider struct {
+	client  *api.Client
+	resolve func(key []string) (string, string)
+	name    string
+	prefix  string
+}
+
+func (p *Provider) Name() string {
+	return p.name
+}
+
+func (p *Provider) Key(in []string) (string, string) {
+	path, val := p.resolve(in)
+	if path == "" {
+		return p.prefix, val
+	}
+
+	return p.prefix + Separator + path, val
+}
+
+func (p *Provider) read(path, key string) (*api.Secret, error) {
+	secret, err := p.client.Logical().Read(path)
+	if err != nil {
+		return nil, fmt.Errorf("read[%s:%s]:%w", path, key, err)
+	}
+
+	if secret == nil && key != ValueName {
+		return p.read(path+Separator+key, ValueName)
+	}
+
+	return secret, nil
+}
+
+func (p *Provider) Value(_ context.Context, key ...string) (config.Value, error) {
+	path, field := p.Key(key)
+
+	secret, err := p.read(path, field)
+	if err != nil {
+		return nil, fmt.Errorf("%w: path:%s, field:%s, provider:%s", err, path, field, p.Name())
+	}
+
+	if secret == nil || len(secret.Data) == 0 {
+		return nil, fmt.Errorf("%w: path:%s, field:%s, provider:%s", config.ErrValueNotFound, path, field, p.Name())
+	}
+
+	if len(secret.Warnings) > 0 {
+		return nil,
+			fmt.Errorf("%w: warn: %s, path:%s, field:%s, provider:%s", config.ErrValueNotFound, secret.Warnings, path, field, p.Name())
+	}
+
+	data, ok := secret.Data["data"].(map[string]interface{})
+	if !ok {
+		return nil, fmt.Errorf("%w: path:%s, field:%s, provider:%s", config.ErrValueNotFound, path, field, p.Name())
+	}
+
+	if val, ok := data[field]; ok {
+		return value.JString(fmt.Sprint(val)), nil
+	}
+
+	if val, ok := data[ValueName]; ok {
+		return value.JString(fmt.Sprint(val)), nil
+	}
+
+	md, err := json.Marshal(data)
+	if err != nil {
+		return nil, fmt.Errorf("%w: %w", config.ErrInvalidValue, err)
+	}
+
+	return value.JBytes(md), nil
+}

provider/vault/provider_example_test.go

@@ -0,0 +1,47 @@
+package vault_test
+
+import (
+	"context"
+	"fmt"
+	"log"
+
+	"gitoa.ru/go-4devs/config"
+	"gitoa.ru/go-4devs/config/provider/vault"
+)
+
+func ExampleClient_Value() {
+	const (
+		namespace = "fdevs"
+		appName   = "config"
+	)
+
+	ctx := context.Background()
+
+	// configure vault client
+	vaultClient, err := NewVault()
+	if err != nil {
+		log.Print(err)
+
+		return
+	}
+
+	config, err := config.New(
+		vault.New(namespace, appName, vaultClient),
+	)
+	if err != nil {
+		log.Print(err)
+
+		return
+	}
+
+	dsn, err := config.Value(ctx, "example", "dsn")
+	if err != nil {
+		log.Print("example:dsn ", err)
+
+		return
+	}
+
+	fmt.Printf("dsn from vault: %s\n", dsn.String())
+	// Output:
+	// dsn from vault: pgsql://user@pass:127.0.0.1:5432
+}

provider/vault/provider_test.go

@@ -0,0 +1,26 @@
+package vault_test
+
+import (
+	"testing"
+	"time"
+
+	"gitoa.ru/go-4devs/config/provider/vault"
+	"gitoa.ru/go-4devs/config/test"
+	"gitoa.ru/go-4devs/config/test/require"
+)
+
+func TestProvider(t *testing.T) {
+	t.Parallel()
+
+	cl, err := NewVault()
+	require.NoError(t, err)
+
+	provider := vault.New("fdevs", "config", cl)
+
+	read := []test.Read{
+		test.NewReadConfig("database"),
+		test.NewRead(test.DSN, "db", "dsn"),
+		test.NewRead(time.Minute, "db", "timeout"),
+	}
+	test.Run(t, provider, read)
+}

provider/vault/vault_test.go

@@ -0,0 +1,90 @@
+package vault_test
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"net/http"
+	"os"
+
+	"github.com/hashicorp/vault/api"
+	"gitoa.ru/go-4devs/config/test"
+)
+
+const token = "dev"
+
+func NewVault() (*api.Client, error) {
+	address, ok := os.LookupEnv("VAULT_DEV_LISTEN_ADDRESS")
+	if !ok {
+		address = "http://127.0.0.1:8200"
+	}
+
+	tokenID, ok := os.LookupEnv("VAULT_DEV_ROOT_TOKEN_ID")
+	if !ok {
+		tokenID = token
+	}
+
+	cl, err := api.NewClient(&api.Config{
+		Address: address,
+	})
+	if err != nil {
+		return nil, err
+	}
+
+	cl.SetToken(tokenID)
+
+	values := map[string]map[string]interface{}{
+		"database": {
+			"duration": 1260000000000,
+			"enabled":  true,
+		},
+		"db": {
+			"dsn":     test.DSN,
+			"timeout": "60s",
+		},
+		"example": {
+			"dsn":     test.DSN,
+			"timeout": "60s",
+		},
+	}
+
+	for name, val := range values {
+		if err := create(address, tokenID, name, val); err != nil {
+			return nil, err
+		}
+	}
+
+	return cl, nil
+}
+
+func create(host, token, path string, data map[string]interface{}) error {
+	type Req struct {
+		Data interface{} `json:"data"`
+	}
+
+	b, err := json.Marshal(Req{Data: data})
+	if err != nil {
+		return err
+	}
+
+	body := bytes.NewBuffer(b)
+
+	req, err := http.NewRequestWithContext(
+		context.Background(),
+		http.MethodPost,
+		host+"/v1/secret/data/fdevs/config/"+path,
+		body,
+	)
+	if err != nil {
+		return err
+	}
+
+	req.Header.Set("X-Vault-Token", token)
+
+	res, err := http.DefaultClient.Do(req)
+	if err != nil {
+		return err
+	}
+
+	return res.Body.Close()
+}