Golang go-playground validator 包中文教程

在Web开发中经常会对用户输入数据进行校验，或者在提供API给第三方使用时候需要对字段进行校验，防止脏数据和恶意请求。 Golang官方维护了 go-playground/validator 是使用最广泛的包，自带了非常多常用的校验规则。其基于标签实现结构和单个字段的值验证。

特性

• 使用验证标签或自定义验证器进行跨字段和跨结构验证。
• slice、array 和 map 层级校验支持，允许验证多维字段的任何或所有级别。
• 支持对 map key 和 value 以进行验证
• 支持处理自定义字段类型，例如 sql driver
• 重命名验证标签，允许将多个验证映射到单个标签，以便更轻松地定义struct上的验证规则
• 支持提取验证数据字段的名称，例如可以指定在验证时提取 JSON 名称，并使其在生成的 FieldError 中可用
• 可设置的 i18n 错误消息。
• gin web 框架的默认验证器

安装

示例

go get github.com/go-playground/validator/v10一键复制

代码中引入包

import "github.com/go-playground/validator/v10"一键复制

简单的用法示例

可以看出我们只用在结构体的字段上加上对应的`validate:"xx"`即可添加对应验证规则。

示例

package main

import (
	"fmt"

	"github.com/go-playground/validator/v10"
)

// User contains user information
type User struct {
	FirstName      string     `validate:"required"`
	LastName       string     `validate:"required"`
	Age            uint8      `validate:"gte=0,lte=130"`
	Email          string     `validate:"required,email"`
	FavouriteColor string     `validate:"iscolor"`                // alias for 'hexcolor|rgb|rgba|hsl|hsla'
	Addresses      []*Address `validate:"required,dive,required"` // a person can have a home and cottage...
}

// Address houses a users address information
type Address struct {
	Street string `validate:"required"`
	City   string `validate:"required"`
	Planet string `validate:"required"`
	Phone  string `validate:"required"`
}

// use a single instance of Validate, it caches struct info
var validate *validator.Validate

func main() {

	validate = validator.New()

	validateStruct()
	validateVariable()
}

func validateStruct() {

	address := &Address{
		Street: "Eavesdown Docks",
		Planet: "Persphone",
		Phone:  "none",
	}

	user := &User{
		FirstName:      "Badger",
		LastName:       "Smith",
		Age:            135,
		Email:          "[email protected]",
		FavouriteColor: "#000-",
		Addresses:      []*Address{address},
	}

	// returns nil or ValidationErrors ( []FieldError )
	err := validate.Struct(user)
	if err != nil {

		// this check is only needed when your code could produce
		// an invalid value for validation such as interface with nil
		// value most including myself do not usually have code like this.
		if _, ok := err.(*validator.InvalidValidationError); ok {
			fmt.Println(err)
			return
		}

		for _, err := range err.(validator.ValidationErrors) {

			fmt.Println(err.Namespace())
			fmt.Println(err.Field())
			fmt.Println(err.StructNamespace())
			fmt.Println(err.StructField())
			fmt.Println(err.Tag())
			fmt.Println(err.ActualTag())
			fmt.Println(err.Kind())
			fmt.Println(err.Type())
			fmt.Println(err.Value())
			fmt.Println(err.Param())
			fmt.Println()
		}

		// from here you can create your own error messages in whatever language you wish
		return
	}

	// save user to database
}

func validateVariable() {

	myEmail := "joeybloggs.gmail.com"

	errs := validate.Var(myEmail, "required,email")

	if errs != nil {
		fmt.Println(errs) // output: Key: "" Error:Field validation for "" failed on the "email" tag
		return
	}

	// email ok, move on
}尝试一下一键复制

验证规则

字段验证规则

标签	说明
eqcsfield	字段等于另一个字段（相对）
eqfield	字段等于另一个字段
fieldcontains	字段包含
fieldexcludes	字段不包含
gtcsfield	Field Greater Than Another Relative Field
gtecsfield	Field Greater Than or Equal To Another Relative Field
gtefield	Field Greater Than or Equal To Another Field
gtfield	Field Greater Than Another Field
ltcsfield	Less Than Another Relative Field
ltecsfield	Less Than or Equal To Another Relative Field
ltefield	Less Than or Equal To Another Field
ltfield	Less Than Another Field
necsfield	Field Does Not Equal Another Field (relative)
nefield	Field Does Not Equal Another Field