connect/middleware/lang.go

package middleware

import (
	"github.com/gin-contrib/i18n"
	"github.com/gin-gonic/gin"
	"golang.org/x/text/language"
)

var translate = map[string]language.Tag{
	"zh-CN": language.Chinese,
	"zh-TW": language.TraditionalChinese,
	"zh-HK": language.TraditionalChinese,
	"zh-MO": language.TraditionalChinese,
	"zh-SG": language.SimplifiedChinese,
}

func Language() i18n.GetLngHandler {
	return func(ctx *gin.Context, defaultLng string) string {
		localization := ctx.GetHeader("Localization")
		if localization == "" {
			localization = defaultLng
		}

		// Translate to golang.org/x/text/language
		if local, ok := translate[localization]; ok {
			localization = local.String()
		}

		ctx.Set("localization", localization)
		return localization
	}
}