Internationalization

Hertz provides the middleware extension for internationalization (i18n), which references Gin’s implementation.

Refer to the below for usage example

Installation

go get github.com/hertz-contrib/i18n

Sample code

package main

import (
    "context"
    "github.com/cloudwego/hertz/pkg/app"
    "github.com/cloudwego/hertz/pkg/app/server"
    hertzI18n "github.com/hertz-contrib/i18n"
    "github.com/nicksnyder/go-i18n/v2/i18n"
)

func main() {
    h := server.New(server.WithHostPorts(":3000"))
    h.Use(hertzI18n.Localize())
    h.GET("/:name", func(c context.Context, ctx *app.RequestContext) {
        ctx.String(200, hertzI18n.MustGetMessage(&i18n.LocalizeConfig{
            MessageID: "welcomeWithName",
            TemplateData: map[string]string{
             "name": ctx.Param("name"),
          },
         }))
    })
	h.GET("/", func(c context.Context, ctx *app.RequestContext) {
        ctx.String(200, hertzI18n.MustGetMessage("welcome"))
	})

      h.Spin()
}

Configuration

Localize

Localize for integrating the i18n extension into the hertz server

Function Signature：

func Localize(opts ...Option) app.HandlerFunc

Sample code：

package main

import (
    "context"
    _ "embed"
    "time"

    "github.com/cloudwego/hertz/pkg/app"
    "github.com/cloudwego/hertz/pkg/app/server"
    hertzI18n "github.com/hertz-contrib/i18n"
    "github.com/nicksnyder/go-i18n/v2/i18n"
    "golang.org/x/text/language"
    "gopkg.in/yaml.v3"
)

func main() {
    h := server.New()
    h.Use(hertzI18n.Localize())
    h.GET("/:name", func(c context.Context, ctx *app.RequestContext) {
        ctx.String(200, hertzI18n.MustGetMessage(&i18n.LocalizeConfig{
            MessageID: "welcomeWithName",
            TemplateData: map[string]string{
                "name": ctx.Param("name"),
            },
        }))
    })
    h.GET("/", func(c context.Context, ctx *app.RequestContext) {
        ctx.String(200, hertzI18n.MustGetMessage("welcome"))
    })

    h.Spin()
}

MustGetMessage

MustGetMessage get the i18n message without error handling

Function Signature：

func MustGetMessage(param interface{}) string

Sample code：

h.GET("/:name", func(c context.Context, ctx *app.RequestContext) {
	ctx.String(200, hertzI18n.MustGetMessage(&i18n.LocalizeConfig{
		MessageID: "welcomeWithName",
		TemplateData: map[string]string{
			"name": ctx.Param("name"),
		},
	}))
})
h.GET("/", func(c context.Context, ctx *app.RequestContext) {
	ctx.String(200, hertzI18n.MustGetMessage("welcome"))
})

LocalizeConfig Configuration item

This configuration item can be viewed by moving to go-i18n

WithBundle

WithBundle is used to load custom configurations into the middleware

Function Signature：

func WithBundle(cfg *BundleCfg) Option

Sample code：

package main

import (
    "context"
    _ "embed"
    "time"

    "github.com/cloudwego/hertz/pkg/app"
    "github.com/cloudwego/hertz/pkg/app/server"
    hertzI18n "github.com/hertz-contrib/i18n"
    "github.com/nicksnyder/go-i18n/v2/i18n"
    "golang.org/x/text/language"
    "gopkg.in/yaml.v3"
)

func main() {
    h := server.New(
        server.WithHostPorts(":3000"),
        server.WithExitWaitTime(time.Second),
    )
    h.Use(hertzI18n.Localize(
        hertzI18n.WithBundle(&hertzI18n.BundleCfg{
            RootPath:         "./localize",
            AcceptLanguage:   []language.Tag{language.Chinese, language.English},
            DefaultLanguage:  language.Chinese,
            FormatBundleFile: "yaml",
            UnmarshalFunc:    yaml.Unmarshal,
        }),
    ))
    h.GET("/:name", func(c context.Context, ctx *app.RequestContext) {
        ctx.String(200, hertzI18n.MustGetMessage(&i18n.LocalizeConfig{
            MessageID: "welcomeWithName",
            TemplateData: map[string]string{
                "name": ctx.Param("name"),
            },
        }))
    })
    h.GET("/", func(c context.Context, ctx *app.RequestContext) {
        ctx.String(200, hertzI18n.MustGetMessage("welcome"))
    })

    h.Spin()
}

Configuration item

Configuration items Type Default value Description
DefaultLanguage language.Tag language.English Default conversion language type
FormatBundleFile string “yaml” Convert file template types，For example yaml, json
AcceptLanguage []language.Tag []language.Tag{defaultLanguage,language.Chinese} Receiving conversion type
RootPath string defaultRootPath Template file directory
UnmarshalFunc i18n.UnmarshalFunc yaml.Unmarshal Template file decoding functions，For example: yaml.Unmarshal
Loader Loader LoaderFunc(ioutil.ReadFile) File reading functions, For example : LoaderFunc(ioutil.ReadFile)

WithGetLangHandle

WithGetLangHandle is used to configure the i18n template trigger conditions, which can be retrieved from the parameters, request headers

Function Signature：

func WithGetLangHandle(handler GetLangHandler)

Sample code：

func main() {
    h := server.New()
	h.Use(hertzI18n.Localize(
		hertzI18n.WithGetLangHandle(
			func(c context.Context, ctx *app.RequestContext, defaultLang string) string {
				lang := ctx.Query("lang")
				if lang == "" {
					return defaultLang
				}
				return lang
			},
		),
	))
	// ...
    h.Spin()
}

Refer to the i18n for more usage examples


Last modified July 13, 2023 : docs: update code example in kitex-generic call (#711) (f80b346)