gin表单验证

功能：

　　1. 对登录和注册表单进行验证

　　2. 对表单返回的错误进行中文翻译

　　3. 对表单返回的数据进行处理，大小写处理和切割

package main

import (
	"fmt"
	"net/http"
	"reflect"
	"strings"

	"github.com/gin-gonic/gin"
	"github.com/gin-gonic/gin/binding"
	"github.com/go-playground/locales/en"
	"github.com/go-playground/locales/zh"
	ut "github.com/go-playground/universal-translator"
	"github.com/go-playground/validator/v10"
	en_translations "github.com/go-playground/validator/v10/translations/en"
	zh_translations "github.com/go-playground/validator/v10/translations/zh"
)

var trans ut.Translator

type LoginForm struct {
	User     string `json:"user" binding:"required,min=3,max=10"`
	Password string `json:"password" binding:"required"`
}

type SignUpForm struct {
	//注册的表单验证
	Age        uint8  `json:"age" binding:"gte=1,lte=130"`
	Name       string `json:"name" binding:"required,min=3"`
	Email      string `json:"email" binding:"required,email"`
	Password   string `json:"password" binding:"required"`
	RePassword string `json:"re_password" binding:"required,eqfield=Password"` //跨字段
}

func removeTopStruct(fileds map[string]string) map[string]string {
	rsp := map[string]string{}
	for field, err := range fileds {
		rsp[field[strings.Index(field, ".")+1:]] = err
	}
	return rsp
}

func InitTrans(locale string) (err error) {
	//修改gin框架中的validator引擎属性, 实现定制
	if v, ok := binding.Validator.Engine().(*validator.Validate); ok {
		//注册一个获取json的tag的自定义方法
		v.RegisterTagNameFunc(func(fld reflect.StructField) string {
			name := strings.SplitN(fld.Tag.Get("json"), ",", 2)[0]
			if name == "-" {
				return ""
			}
			return name
		})

		zhT := zh.New() //中文翻译器
		enT := en.New() //英文翻译器
		//第一个参数是备用的语言环境，后面的参数是应该支持的语言环境
		uni := ut.New(enT, zhT, enT)
		trans, ok = uni.GetTranslator(locale)
		if !ok {
			return fmt.Errorf("uni.GetTranslator(%s)", locale)
		}

		switch locale {
		case "en":
			en_translations.RegisterDefaultTranslations(v, trans)
		case "zh":
			zh_translations.RegisterDefaultTranslations(v, trans)
		default:
			en_translations.RegisterDefaultTranslations(v, trans)
		}
		return
	}

	return
}

func main() {
	//代码侵入性很强 中间件
	if err := InitTrans("zh"); err != nil {
		fmt.Println("初始化翻译器错误")
		return
	}
	router := gin.Default()
	router.POST("/loginJSON", func(c *gin.Context) {

		var loginForm LoginForm
		if err := c.ShouldBind(&loginForm); err != nil {
			errs, ok := err.(validator.ValidationErrors)
			if !ok {
				c.JSON(http.StatusOK, gin.H{
					"msg": err.Error(),
				})
			}
			c.JSON(http.StatusBadRequest, gin.H{
				"error": removeTopStruct(errs.Translate(trans)),
			})
			return
		}

		c.JSON(http.StatusOK, gin.H{
			"msg": "登录成功",
		})
	})

	router.POST("/signup", func(c *gin.Context) {
		var signUpFrom SignUpForm
		if err := c.ShouldBind(&signUpFrom); err != nil {
			fmt.Println(err.Error())
			c.JSON(http.StatusBadRequest, gin.H{
				"error": err.Error(),
			})
			return
		}

		c.JSON(http.StatusOK, gin.H{
			"msg": "注册成功",
		})
	})

	_ = router.Run(":8083")
}