add config definition

Reviewed-on: https://gitoa.ru/go-4devs/config/pulls/10
Co-authored-by: andrey <andrey@4devs.io>
Co-committed-by: andrey <andrey@4devs.io>

.drone.yml

@@ -145,3 +145,21 @@ steps:
   - cd provider/vault
   - golangci-lint run
 
+---
+kind: pipeline
+type: docker
+name: definition
+
+steps:
+- name: test 
+  image: golang
+  commands:
+  - cd provider/definition
+  - go test ./... 
+
+- name: golangci-lint
+  image: golangci/golangci-lint:v1.55
+  commands:
+  - cd provider/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
+}
+`
+)