golang常用库:字段参数验证库-validator使用
转载一个大佬的博客,mark一下方便自己学习,原文地址:
https://www.cnblogs.com/jiujuan/p/13823864.html
golang常用库:字段参数验证库-validator使用
golang常用库:gorilla/mux-http路由库使用
golang常用库:配置文件解析库/管理工具-viper使用
golang常用库:操作数据库的orm框架-gorm基本使用
golang常用库:字段参数验证库-validator使用
一、背景#
在平常开发中,特别是在web应用开发中,为了验证输入字段的合法性,都会做一些验证操作。比如对用户提交的表单字段进行验证,或者对请求的API接口字段进行验证,验证字段的合法性,保证输入字段值的安全,防止用户的恶意请求。
一般的做法是用正则表达式,一个字段一个字段的进行验证。一个一个字段验证的话,写起来比较繁琐。那有没更好的方法,进行字段的合法性验证?有, 这就是下面要介绍的 validator 这个验证组件。
代码地址:
https://github.com/go-playground/validator
文档地址:
https://github.com/go-playground/validator/blob/master/README.md
二、功能介绍#
这个验证包 github.com/go-playground/validator 验证功能非常多。
标记之间特殊符号说明#
- 逗号(
,
):把多个验证标记隔开。注意
:隔开逗号之间不能有空格,validate:"lt=0,gt=100"
,逗号那里不能有空格,否则panic - 横线(
-
):跳过该字段不验证 - 竖线(
|
):使用多个验证标记,但是只需满足其中一个即可 - required:表示该字段值必输设置,且不能为默认值
- omitempty:如果字段未设置,则忽略它
范围比较验证#
doc: https://github.com/go-playground/validator/blob/master/README.md#comparisons
范围验证: 切片、数组和map、字符串,验证其长度;数值,验证大小范围
- lte:小于等于参数值,
validate:"lte=3"
(小于等于3) - gte:大于等于参数值,
validate:"lte=120,gte=0"
(大于等于0小于等于120) - lt:小于参数值,
validate:"lt=3"
(小于3) - gt:大于参数值,
validate:"lt=120,gt=0"
(大于0小于120) - len:等于参数值,
validate:"len=2"
- max:最大值,小于等于参数值,
validate:"max=20"
(小于等于20) - min:最小值,大于等于参数值,
validate:"min=2,max=20"
(大于等于2小于等于20) - ne:不等于,
validate:"ne=2"
(不等于2) - oneof:只能是列举出的值其中一个,这些值必须是数值或字符串,以空格分隔,如果字符串中有空格,将字符串用单引号包围,
validate:"oneof=red green"
例子:
Copytype User struct {
Name string `json:"name" validate:"min=0,max=35"`
Age unit8 `json:"age" validate:"lte=90,gte=0"`
}
更多功能请参看文档 validator comparisons doc
字符串验证#
doc: https://github.com/go-playground/validator/blob/master/README.md#strings
- contains:包含参数子串,
validate:"contains=tom"
(字段的字符串值包含tom) - excludes:包含参数子串,
validate:"excludes=tom"
(字段的字符串值不包含tom) - startswith:以参数子串为前缀,
validate:"startswith=golang"
- endswith:以参数子串为后缀,
validate:"startswith=world"
例子:
Copytype User struct {
Name string `validate:"contains=tom"`
Age int `validate:"min=1"`
}
更多功能请参看文档 validator strings doc
字段验证#
doc: https://github.com/go-playground/validator/blob/master/README.md#fields
- eqcsfield:跨不同结构体字段验证,比如说 Struct1 Filed1,与结构体Struct2 Field2相等,
Copytype Struct1 struct {
Field1 string `validate:eqcsfield=Struct2.Field2`
Struct2 struct {
Field2 string
}
}
- necsfield:跨不同结构体字段不相等
- eqfield:同一结构体字段验证相等,最常见的就是输入2次密码验证
Copytype User struct {
Name string `validate:"lte=4"`
Age int `validate:"min=20"`
Password string `validate:"min=10"`
Password2 string `validate:"eqfield=Password"`
}
- nefield:同一结构体字段验证不相等
Copytype User struct {
Name string `validate:"lte=4"`
Age int `validate:"min=20"`
Password string `validate:"min=10,nefield=Name"`
}
- gtefield:大于等于同一结构体字段,
validate:"gtefiled=Field2"
- ltefield:小于等于同一结构体字段
更多功能请参看文档:validator Fields DOC
网络验证#
doc: https://github.com/go-playground/validator/blob/master/README.md#network
- ip:字段值是否包含有效的IP地址,
validate:"ip"
- ipv4:字段值是否包含有效的ipv4地址,
validate:"ipv4"
- ipv6:字段值是否包含有效的ipv6地址,
validate:"ipv6"
- uri:字段值是否包含有效的uri,
validate:"uri"
- url:字段值是否包含有效的uri,
validate:"url"
更多功能请参看文档:validator network DOC
Format#
doc: https://github.com/go-playground/validator/blob/master/README.md#format
- base64:字段值是否包含有效的base64值
更多功能请参看文档 validator strings doc
其他#
请参看文档: https://github.com/go-playground/validator/blob/master/README.md#other
三、安装#
go get:
go get github.com/go-playground/validator/v10
在文件中引用validator包:
import "github.com/go-playground/validator/v10"
四、validator使用#
文档:https://github.com/go-playground/validator/blob/master/README.md#examples
例子1:验证单个字段变量值#
validation1.go
Copypackage main
import (
"fmt"
"github.com/go-playground/validator/v10"
)
func main() {
validate := validator.New()
var boolTest bool
err := validate.Var(boolTest, "required")
if err != nil {
fmt.Println(err)
}
var stringTest string = ""
err = validate.Var(stringTest, "required")
if err != nil {
fmt.Println(err)
}
var emailTest string = "test@126.com"
err = validate.Var(emailTest, "email")
if err != nil {
fmt.Println(err)
} else {
fmt.Println("success") // 输出: success。 说明验证成功
}
emailTest2 := "test.126.com"
errs := validate.Var(emailTest2, "required,email")
if errs != nil {
fmt.Println(errs) // 输出: Key: "" Error:Field validation for "" failed on the "email" tag。验证失败
}
fmt.Println("\r\nEnd!!")
}
运行输出:
go run simple1.go
Key: '' Error:Field validation for '' failed on the 'required' tag
Key: '' Error:Field validation for '' failed on the 'required' tag
success
Key: '' Error:Field validation for '' failed on the 'email' tagEnd!!
例子2:验证结构体struct#
from:struct validate
validation_struct.go,这个程序还列出了效验出错字段的一些信息,
Copypackage main
import (
"fmt"
"github.com/go-playground/validator/v10"
)
type User struct {
FirstName string `validate:"required"`
LastName string `validate:"required"`
Age uint8 `validate:"gte=0,lte=130"`
Email string `validate:"required,email"`
Addresses []*Address `validate:"required,dive,required"`
}
type Address struct {
Street string `validate:"required"`
City string `validate:"required"`
Planet string `validate:"required"`
Phone string `validate:"required"`
}
func main() {
address := &Address{
Street: "Eavesdown Docks",
Planet: "Persphone",
Phone: "none",
}
user := &User{
FirstName: "Badger",
LastName: "Smith",
Age: 135,
Email: "Badger.Smith@gmail.com",
Addresses: []*Address{address},
}
validate := validator.New()
err := validate.Struct(user)
if err != nil {
fmt.Println("=== error msg ====")
fmt.Println(err)
if _, ok := err.(*validator.InvalidValidationError); ok {
fmt.Println(err)
return
}
fmt.Println("\r\n=========== error field info ====================")
for _, err := range err.(validator.ValidationErrors) {
// 列出效验出错字段的信息
fmt.Println("Namespace: ", err.Namespace())
fmt.Println("Fild: ", err.Field())
fmt.Println("StructNamespace: ", err.StructNamespace())
fmt.Println("StructField: ", err.StructField())
fmt.Println("Tag: ", err.Tag())
fmt.Println("ActualTag: ", err.ActualTag())
fmt.Println("Kind: ", err.Kind())
fmt.Println("Type: ", err.Type())
fmt.Println("Value: ", err.Value())
fmt.Println("Param: ", err.Param())
fmt.Println()
}
// from here you can create your own error messages in whatever language you wish
return
}
}
运行 输出:
$ go run validation_struct.go
=== error msg ====
Key: 'User.Age' Error:Field validation for 'Age' failed on the 'lte' tag
Key: 'User.Addresses[0].City' Error:Field validation for 'City' failed on the 'required' tag=========== error field info ====================
Namespace: User.Age
Fild: Age
StructNamespace: User.Age
StructField: Age
Tag: lte
ActualTag: lte
Kind: uint8
Type: uint8
Value: 135
Param: 130Namespace: User.Addresses[0].City
Fild: City
StructNamespace: User.Addresses[0].City
StructField: City
Tag: required
ActualTag: required
Kind: string
Type: string
Value:
Param:
还可以给字段加一些其他tag信息,方面form,json的解析,如下:
Copytype User struct {
FirstName string `form:"firstname" json:"firstname" validate:"required"`
LastName string `form:"lastname" json:"lastname" validate:"required"`
Age uint8 ` form:"age" json:"age"validate:"gte=0,lte=130"`
Email string ` form:"email" json:"email" validate:"required,email"`
}
例子2.2:验证slice map#
slice#
slice验证中用到一个tag关键字 dive
, 意思深入一层验证。
validate_slice.go
Copypackage main
import (
"fmt"
"github.com/go-playground/validator/v10"
)
func main() {
sliceone := []string{"123", "onetwothree", "myslicetest", "four", "five"}
validate := validator.New()
err := validate.Var(sliceone, "max=15,dive,min=4")
if err != nil {
fmt.Println(err)
}
slicetwo := []string{}
err = validate.Var(slicetwo, "min=4,dive,required")
if err != nil {
fmt.Println(err)
}
}
运行输出:
$ go run validate_slice.go
Key: '[0]' Error:Field validation for '[0]' failed on the 'min' tag
Key: '' Error:Field validation for '' failed on the 'min' tag
说明:
Copysliceone := []string{"123", "onetwothree", "myslicetest", "four", "five"}
validate.Var(sliceone, "max=15,dive,min=4")
第二个参数中tag关键字
dive
前面的 max=15,验证 [] , 也就是验证slice的长度,dive
后面的 min=4,验证slice里的值长度,也就是说 dive 后面的 tag 验证 slice 的值
那如果是二维slice验证呢?如:
Copyslicethree := [][]string{}
validate.Var(slicethree, "min=2,dive,len=2,dive,required")
validate.Var(slicethree, "min=2,dive,dive,required")
说明:
这里有2个 dive,刚好深入到二维slice,但他们也有不同之处,第二个表达式的第一个dive后没有设置tag。
第一个验证表达式:
min=2:验证第一个 [] 方括号的值长度 ;
len=2:验证第二个 []string 长度;
required:验证slice里的值
第二个验证表达式:
min=2:验证第一个 [] 方括号的值长度 ;
dive: 后没有设置tag值,不验证第二个 []string ;
required: 验证slice里的值
map#
map的验证中也需要tag关键字 dive
, 另外,它还有 keys
和 endkeys
两tag,验证这2个tag之间map的 key,而不是value值。
validate_map.go
Copypackage main
import (
"fmt"
"github.com/go-playground/validator/v10"
)
func main() {
var mapone map[string]string
mapone = map[string]string{"one": "jimmmy", "two": "tom", "three": ""}
validate := validator.New()
err := validate.Var(mapone, "gte=3,dive,keys,eq=1|eq=2,endkeys,required")
if err != nil {
fmt.Println(err)
}
}
运行输出:
$ go run validate_map.go
Key: '[three]' Error:Field validation for '[three]' failed on the 'eq=1|eq=3' tag
Key: '[three]' Error:Field validation for '[three]' failed on the 'required' tag
Key: '[one]' Error:Field validation for '[one]' failed on the 'eq=1|eq=3' tag
Key: '[two]' Error:Field validation for '[two]' failed on the 'eq=1|eq=3' tag
说明:
gte=3:验证map自己的长度;
dive后的 keys,eq=1|eq=2,endkeys:验证map的keys个数,也就是验证 [] 里值。上例中定义了一个string,所以明显报了3个错误。
required:验证 map的值value
那嵌套map怎么验证?
如:map[[3]string]string,和上面slice差不多,使用多个 dive
Copyvar maptwo map[[3]string]string{}
validate.Var(maptwo, "gte=3,dive,keys,dive,eq=1|eq=3,endkeys,required")
说明:
gte=3: 验证map的长度;
keys,dive,eq=1|eq=3,endkeys:keys和endkeys中有一个dive(深入一级),验证map中key的数组每一个值
required: 验证map的值
用户自定义函数验证#
用户自定义函数验证字段是否合法,效验是否正确。
例子3: 通过字段tag自定义函数#
validate.RegisterValidation
customer_tag.go:
Copypackage main
import (
"fmt"
"github.com/go-playground/validator/v10"
)
type User struct {
Name string `form:"name" json:"name" validate:"required,CustomerValidation"` //注意:required和CustomerValidation之间不能有空格,否则panic。CustomerValidation:自定义tag-函数标签
Age uint8 ` form:"age" json:"age" validate:"gte=0,lte=80"` //注意:gte=0和lte=80之间不能有空格,否则panic
}
var validate *validator.Validate
func main() {
validate = validator.New()
validate.RegisterValidation("CustomerValidation", CustomerValidationFunc) //注册自定义函数,前一个参数是struct里tag自定义,后一个参数是自定义的函数
user := &User{
Name: "jimmy",
Age: 86,
}
fmt.Println("first value: ", user)
err := validate.Struct(user)
if err != nil {
fmt.Printf("Err(s):\n%+v\n", err)
}
user.Name = "tom"
user.Age = 29
fmt.Println("second value: ", user)
err = validate.Struct(user)
if err != nil {
fmt.Printf("Err(s):\n%+v\n", err)
}
}
// 自定义函数
func CustomerValidationFunc(f1 validator.FieldLevel) bool {
// f1 包含了字段相关信息
// f1.Field() 获取当前字段信息
// f1.Param() 获取tag对应的参数
// f1.FieldName() 获取字段名称
return f1.Field().String() == "jimmy"
}
运行输出:
$ go run customer.go
first value: &{jimmy 86}
Err(s):
Key: 'User.Age' Error:Field validation for 'Age' failed on the 'lte' tag
second value: &{tom 29}
Err(s):
Key: 'User.Name' Error:Field validation for 'Name' failed on the 'CustomerValidation' tag
**注意:
上面代码user struct
定义中 ,validate
里的required和CustomerValidation之间不能有空格,否则运行时报panic错误:panic: Undefined validation function ' CustomerValidation' on field 'Name'
例子4:自定义函数-直接注册函数1#
不通过字段tag自定义函数,直接注册函数。
RegisterStructValidation
https://github.com/go-playground/validator/blob/master/_examples/struct-level/main.go
customer1.go
Copypackage main
import (
"fmt"
"github.com/go-playground/validator/v10"
)
type User struct {
FirstName string `json:firstname`
LastName string `json:lastname`
Age uint8 `validate:"gte=0,lte=130"`
Email string `validate:"required,email"`
FavouriteColor string `validate:"hexcolor|rgb|rgba"`
}
var validate *validator.Validate
func main() {
validate = validator.New()
validate.RegisterStructValidation(UserStructLevelValidation, User{})
user := &User{
FirstName: "",
LastName: "",
Age: 30,
Email: "TestFunc@126.com",
FavouriteColor: "#000",
}
err := validate.Struct(user)
if err != nil {
fmt.Println(err)
}
}
func UserStructLevelValidation(sl validator.StructLevel) {
user := sl.Current().Interface().(User)
if len(user.FirstName) == 0 && len(user.LastName) == 0 {
sl.ReportError(user.FirstName, "FirstName", "firstname", "firstname", "")
sl.ReportError(user.LastName, "LastName", "lastname", "lastname", "")
}
}
运行输出:
$ go run customer1.go
Key: 'User.FirstName' Error:Field validation for 'FirstName' failed on the 'firstname' tag
Key: 'User.LastName' Error:Field validation for 'LastName' failed on the 'lastname' tag
例子5:自定义函数-直接注册函数2#
RegisterCustomTypeFunc
https://github.com/go-playground/validator/blob/master/_examples/custom/main.go
validate.RegisterCustomTypeFunc:验证类型的自定义函数
customer2.go:
Copypackage main
import (
"database/sql"
"database/sql/driver"
"fmt"
"reflect"
"github.com/go-playground/validator/v10"
)
type DbBackedUser struct {
Name sql.NullString `validate:"required"`
Age sql.NullInt64 `validate:"required"`
}
var validate *validator.Validate
func main() {
validate = validator.New()
validate.RegisterCustomTypeFunc(ValidateValuer, sql.NullString{}, sql.NullInt64{}, sql.NullBool{}, sql.NullFloat64{})
// build object for validation
x := DbBackedUser{Name: sql.NullString{String: "", Valid: true}, Age: sql.NullInt64{Int64: 0, Valid: false}}
err := validate.Struct(x)
if err != nil {
fmt.Printf("Err(s):\n%+v\n", err)
}
}
func ValidateValuer(field reflect.Value) interface{} {
if valuer, ok := field.Interface().(driver.Valuer); ok {
val, err := valuer.Value()
if err == nil {
return val
}
// handle the error how you want
}
return nil
}
运行输出:
$ go run customer.go
Err(s):
Key: 'DbBackedUser.Name' Error:Field validation for 'Name' failed on the 'required' tag
Key: 'DbBackedUser.Age' Error:Field validation for 'Age' failed on the 'required' tag
注意,这个函数:
RegisterCustomTypeFunc,它上面有2行注释:
// RegisterCustomTypeFunc registers a CustomTypeFunc against a number of types
//
// NOTE: this method is not thread-safe it is intended that these all be registered prior to any validation
它是一个验证数据类型自定义函数,NOTE:这个方法不是线程安全的
例子6:两字段比较#
两个字段比较,有一种是密码比较验证,用户注册时候验证2次密码输入是否相同。用tag eqfield
比较两字段。。
verify_pwd.go:
Copypackage main
import (
"fmt"
"github.com/go-playground/validator/v10"
)
// 注册用户 user struct
type User struct {
UserName string `json:"username" validate:"lte=14,gte=4"`
Password string `json:"password" validate:"max=20,min=6"`
Password2 string `json:"password2" validate:"eqfield=Password"`
}
func main() {
validate := validator.New()
user1 := User{
UserName: "jim",
Password: "123456",
Password2: "12345",
}
fmt.Println("validate user1 value: ", user1)
err := validate.Struct(user1)
if err != nil {
fmt.Println(err)
}
fmt.Println("====================")
user2 := User{
UserName: "jimy",
Password: "123456",
Password2: "123456",
}
fmt.Println("validate user2 value: ", user2)
err = validate.Struct(user2)
if err != nil {
fmt.Println(err)
}
}
运行输出:
$ go run verify_pwd.go
validate user1 value: {jim 123456 12345}
Key: 'User.UserName' Error:Field validation for 'UserName' failed on the 'gte' tag
Key: 'User.Password2' Error:Field validation for 'Password2' failed on the 'eqfield' tagvalidate user2 value:
还有一种是2变量字段比较,见下面例子 eq_field.go:
Copypackage main
import (
"fmt"
"github.com/go-playground/validator/v10"
)
func main() {
field1 := "tom"
field2 := "jimmy"
validate := validator.New()
fmt.Println("tag nefield: ")
err := validate.VarWithValue(field1, field2, "nefield")
if err != nil {
fmt.Println(err)
} else {
fmt.Println("correct")
}
fmt.Println("===========================")
fmt.Println("tag eqfield: ")
err = validate.VarWithValue(field1, field2, "eqfield")
if err != nil {
fmt.Println(err)
}
}
运行输出:
$ go run eq_field.go
tag nefield:
correcttag eqfield:
Key: '' Error:Field validation for '' failed on the 'eqfield' tag
例子7:翻译/自定义字段错误#
Copypackage main
import (
"fmt"
"strings"
"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"
zhtrans "github.com/go-playground/validator/v10/translations/zh"
// entrans "github.com/go-playground/validator/v10/translations/en"
)
type Student struct {
Name string `validate:required`
Email string `validate:"email"`
Age int `validate:"max=30,min=12"`
}
func main() {
en := en.New() //英文翻译器
zh := zh.New() //中文翻译器
// 第一个参数是必填,如果没有其他的语言设置,就用这第一个
// 后面的参数是支持多语言环境(
// uni := ut.New(en, en) 也是可以的
// uni := ut.New(en, zh, tw)
uni := ut.New(en, zh)
trans, _ := uni.GetTranslator("zh") //获取需要的语言
student := Student{
Name: "tom",
Email: "testemal",
Age: 40,
}
validate := validator.New()
zhtrans.RegisterDefaultTranslations(validate, trans)
err := validate.Struct(student)
if err != nil {
// fmt.Println(err)
errs := err.(validator.ValidationErrors)
fmt.Println(removeStructName(errs.Translate(trans)))
}
}
func removeStructName(fields map[string]string) map[string]string {
result := map[string]string{}
for field, err := range fields {
result[field[strings.Index(field, ".")+1:]] = err
}
return result
}
运行输出:
$ go run customer_err_info3.go
map[Age:Age必须小于或等于30 Email:Email必须是一个有效的邮箱]
五、参考#
- https://github.com/go-playground/validator/blob/master/README.md
- https://github.com/go-playground/validator/tree/master/_examples
- https://github.com/go-playground/universal-translator/tree/master/_examples
- https://github.com/go-playground/validator/issues/633
- validator translator
作者: 九卷
出处:https://www.cnblogs.com/jiujuan/p/13823864.html
版权:本文采用「署名-非商业性使用-相同方式共享 4.0 国际」知识共享许可协议进行许可。
分类: [01]Go
1
0
« 上一篇: golang常用库:配置文件解析库/管理工具-viper使用
» 下一篇: 技术人沟通中的几个常见问题分析和解答
posted @ 2020-10-15 23:42 九卷 阅读(11763) 评论(2) 编辑 [收藏](javascript:void(0)) [举报](javascript:void(0))