validator

package
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 Go to latest Published: Nov 28, 2019 License: GPL-3.0, MIT Imports: 13 Imported by: 0

README

Package validator

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Package validator implements value validations for structs and individual fields based on tags.

It has the following unique features:

  • Cross Field and Cross Struct validations by using validation tags or custom validators.
  • Slice, Array and Map diving, which allows any or all levels of a multidimensional field to be validated.
  • Handles type interface by determining it's underlying type prior to validation.
  • Handles custom field types such as sql driver Valuer see Valuer
  • Alias validation tags, which allows for mapping of several validations to a single tag for easier defining of validations on structs
  • Extraction of custom defined Field Name e.g. can specify to extract the JSON name while validating and have it available in the resulting FieldError

Installation

Use go get.

go get gopkg.in/go-playground/validator.v8

or to update

go get -u gopkg.in/go-playground/validator.v8

Then import the validator package into your own code.

import "gopkg.in/go-playground/validator.v8"

Error Return Value

Validation functions return type error

They return type error to avoid the issue discussed in the following, where err is always != nil:

validator only returns nil or ValidationErrors as type error; so in you code all you need to do is check if the error returned is not nil, and if it's not type cast it to type ValidationErrors like so:

err := validate.Struct(mystruct)
validationErrors := err.(validator.ValidationErrors)

Usage and documentation

Please see http://godoc.org/gopkg.in/go-playground/validator.v8 for detailed usage docs.

Examples:

Struct & Field validation

package main

import (
	"fmt"

	"gopkg.in/go-playground/validator.v8"
)

// 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:"hexcolor|rgb|rgba"`
	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"`
}

var validate *validator.Validate

func main() {

	config := &validator.Config{TagName: "validate"}

	validate = validator.New(config)

	validateStruct()
	validateField()
}

func validateStruct() {

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

	user := &User{
		FirstName:      "Badger",
		LastName:       "Smith",
		Age:            135,
		Email:          "Badger.Smith@gmail.com",
		FavouriteColor: "#000",
		Addresses:      []*Address{address},
	}

	// returns nil or ValidationErrors ( map[string]*FieldError )
	errs := validate.Struct(user)

	if errs != nil {

		fmt.Println(errs) // output: 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
		err := errs.(validator.ValidationErrors)["User.Addresses[0].City"]
		fmt.Println(err.Field) // output: City
		fmt.Println(err.Tag)   // output: required
		fmt.Println(err.Kind)  // output: string
		fmt.Println(err.Type)  // output: string
		fmt.Println(err.Param) // output:
		fmt.Println(err.Value) // output:

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

	// save user to database
}

func validateField() {
	myEmail := "joeybloggs.gmail.com"

	errs := validate.Field(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
}

Custom Field Type

package main

import (
	"database/sql"
	"database/sql/driver"
	"fmt"
	"reflect"

	"gopkg.in/go-playground/validator.v8"
)

// DbBackedUser User struct
type DbBackedUser struct {
	Name sql.NullString `validate:"required"`
	Age  sql.NullInt64  `validate:"required"`
}

func main() {

	config := &validator.Config{TagName: "validate"}

	validate := validator.New(config)

	// register all sql.Null* types to use the ValidateValuer CustomTypeFunc
	validate.RegisterCustomTypeFunc(ValidateValuer, sql.NullString{}, sql.NullInt64{}, sql.NullBool{}, sql.NullFloat64{})

	x := DbBackedUser{Name: sql.NullString{String: "", Valid: true}, Age: sql.NullInt64{Int64: 0, Valid: false}}
	errs := validate.Struct(x)

	if len(errs.(validator.ValidationErrors)) > 0 {
		fmt.Printf("Errs:\n%+v\n", errs)
	}
}

// ValidateValuer implements validator.CustomTypeFunc
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
}

Struct Level Validation

package main

import (
	"fmt"
	"reflect"

	"gopkg.in/go-playground/validator.v8"
)

// User contains user information
type User struct {
	FirstName      string     `json:"fname"`
	LastName       string     `json:"lname"`
	Age            uint8      `validate:"gte=0,lte=130"`
	Email          string     `validate:"required,email"`
	FavouriteColor string     `validate:"hexcolor|rgb|rgba"`
	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"`
}

var validate *validator.Validate

func main() {

	config := &validator.Config{TagName: "validate"}

	validate = validator.New(config)
	validate.RegisterStructValidation(UserStructLevelValidation, User{})

	validateStruct()
}

// UserStructLevelValidation contains custom struct level validations that don't always
// make sense at the field validation level. For Example this function validates that either
// FirstName or LastName exist; could have done that with a custom field validation but then
// would have had to add it to both fields duplicating the logic + overhead, this way it's
// only validated once.
//
// NOTE: you may ask why wouldn't I just do this outside of validator, because doing this way
// hooks right into validator and you can combine with validation tags and still have a
// common error output format.
func UserStructLevelValidation(v *validator.Validate, structLevel *validator.StructLevel) {

	user := structLevel.CurrentStruct.Interface().(User)

	if len(user.FirstName) == 0 && len(user.LastName) == 0 {
		structLevel.ReportError(reflect.ValueOf(user.FirstName), "FirstName", "fname", "fnameorlname")
		structLevel.ReportError(reflect.ValueOf(user.LastName), "LastName", "lname", "fnameorlname")
	}

	// plus can to more, even with different tag than "fnameorlname"
}

func validateStruct() {

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

	user := &User{
		FirstName:      "",
		LastName:       "",
		Age:            45,
		Email:          "Badger.Smith@gmail.com",
		FavouriteColor: "#000",
		Addresses:      []*Address{address},
	}

	// returns nil or ValidationErrors ( map[string]*FieldError )
	errs := validate.Struct(user)

	if errs != nil {

		fmt.Println(errs) // output: Key: 'User.LastName' Error:Field validation for 'LastName' failed on the 'fnameorlname' tag
		//	                         Key: 'User.FirstName' Error:Field validation for 'FirstName' failed on the 'fnameorlname' tag
		err := errs.(validator.ValidationErrors)["User.FirstName"]
		fmt.Println(err.Field) // output: FirstName
		fmt.Println(err.Tag)   // output: fnameorlname
		fmt.Println(err.Kind)  // output: string
		fmt.Println(err.Type)  // output: string
		fmt.Println(err.Param) // output:
		fmt.Println(err.Value) // output:

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

	// save user to database
}

Benchmarks

Run on MacBook Pro (Retina, 15-inch, Late 2013) 2.6 GHz Intel Core i7 16 GB 1600 MHz DDR3 using Go version go1.5.3 darwin/amd64
PASS
BenchmarkFieldSuccess-8                            	20000000	       118 ns/op	       0 B/op	       0 allocs/op
BenchmarkFieldFailure-8                            	 2000000	       758 ns/op	     432 B/op	       4 allocs/op
BenchmarkFieldDiveSuccess-8                        	  500000	      2471 ns/op	     464 B/op	      28 allocs/op
BenchmarkFieldDiveFailure-8                        	  500000	      3172 ns/op	     896 B/op	      32 allocs/op
BenchmarkFieldCustomTypeSuccess-8                  	 5000000	       300 ns/op	      32 B/op	       2 allocs/op
BenchmarkFieldCustomTypeFailure-8                  	 2000000	       775 ns/op	     432 B/op	       4 allocs/op
BenchmarkFieldOrTagSuccess-8                       	 1000000	      1122 ns/op	       4 B/op	       1 allocs/op
BenchmarkFieldOrTagFailure-8                       	 1000000	      1167 ns/op	     448 B/op	       6 allocs/op
BenchmarkStructLevelValidationSuccess-8            	 3000000	       548 ns/op	     160 B/op	       5 allocs/op
BenchmarkStructLevelValidationFailure-8            	 3000000	       558 ns/op	     160 B/op	       5 allocs/op
BenchmarkStructSimpleCustomTypeSuccess-8           	 2000000	       623 ns/op	      36 B/op	       3 allocs/op
BenchmarkStructSimpleCustomTypeFailure-8           	 1000000	      1381 ns/op	     640 B/op	       9 allocs/op
BenchmarkStructPartialSuccess-8                    	 1000000	      1036 ns/op	     272 B/op	       9 allocs/op
BenchmarkStructPartialFailure-8                    	 1000000	      1734 ns/op	     730 B/op	      14 allocs/op
BenchmarkStructExceptSuccess-8                     	 2000000	       888 ns/op	     250 B/op	       7 allocs/op
BenchmarkStructExceptFailure-8                     	 1000000	      1036 ns/op	     272 B/op	       9 allocs/op
BenchmarkStructSimpleCrossFieldSuccess-8           	 2000000	       773 ns/op	      80 B/op	       4 allocs/op
BenchmarkStructSimpleCrossFieldFailure-8           	 1000000	      1487 ns/op	     536 B/op	       9 allocs/op
BenchmarkStructSimpleCrossStructCrossFieldSuccess-8	 1000000	      1261 ns/op	     112 B/op	       7 allocs/op
BenchmarkStructSimpleCrossStructCrossFieldFailure-8	 1000000	      2055 ns/op	     576 B/op	      12 allocs/op
BenchmarkStructSimpleSuccess-8                     	 3000000	       519 ns/op	       4 B/op	       1 allocs/op
BenchmarkStructSimpleFailure-8                     	 1000000	      1429 ns/op	     640 B/op	       9 allocs/op
BenchmarkStructSimpleSuccessParallel-8             	10000000	       146 ns/op	       4 B/op	       1 allocs/op
BenchmarkStructSimpleFailureParallel-8             	 2000000	       551 ns/op	     640 B/op	       9 allocs/op
BenchmarkStructComplexSuccess-8                    	  500000	      3269 ns/op	     244 B/op	      15 allocs/op
BenchmarkStructComplexFailure-8                    	  200000	      8436 ns/op	    3609 B/op	      60 allocs/op
BenchmarkStructComplexSuccessParallel-8            	 1000000	      1024 ns/op	     244 B/op	      15 allocs/op
BenchmarkStructComplexFailureParallel-8            	  500000	      3536 ns/op	    3609 B/op	      60 allocs/op

Complimentary Software

Here is a list of software that compliments using this library either pre or post validation.

  • form - Decodes url.Values into Go value(s) and Encodes Go value(s) into url.Values. Dual Array and Full map support.
  • Conform - Trims, sanitizes & scrubs data based on struct tags.

How to Contribute

There will always be a development branch for each version i.e. v1-development. In order to contribute, please make your pull requests against those branches.

If the changes being proposed or requested are breaking changes, please create an issue, for discussion or create a pull request against the highest development branch for example this package has a v1 and v1-development branch however, there will also be a v2-development branch even though v2 doesn't exist yet.

I strongly encourage everyone whom creates a custom validation function to contribute them and help make this package even better.

License

Distributed under MIT License, please see license file in code for more details.

Documentation

Overview

Package validator implements value validations for structs and individual fields based on tags.

It can also handle Cross-Field and Cross-Struct validation for nested structs and has the ability to dive into arrays and maps of any type.

Why not a better error message? Because this library intends for you to handle your own error messages.

Why should I handle my own errors? Many reasons. We built an internationalized application and needed to know the field, and what validation failed so we could provide a localized error. 

if fieldErr.Field == "Name" {
	switch fieldErr.ErrorTag
	case "required":
		return "Translated string based on field + error"
	default:
	return "Translated string based on field"
}

Validation Functions Return Type error

Doing things this way is actually the way the standard library does, see the file.Open method here: 

https://golang.org/pkg/os/#Open.

The authors return type "error" to avoid the issue discussed in the following, where err is always != nil: 

http://stackoverflow.com/a/29138676/3158232
https://github.com/go-playground/validator/issues/134

Validator only returns nil or ValidationErrors as type error; so, in your code all you need to do is check if the error returned is not nil, and if it's not type cast it to type ValidationErrors like so err.(validator.ValidationErrors).

Custom Functions

Custom functions can be added. Example: 

// Structure
func customFunc(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool {

	if whatever {
		return false
	}

	return true
}

validate.RegisterValidation("custom tag name", customFunc)
// NOTES: using the same tag name as an existing function
//        will overwrite the existing one

Cross-Field Validation

Cross-Field Validation can be done via the following tags:

  • eqfield
  • nefield
  • gtfield
  • gtefield
  • ltfield
  • ltefield
  • eqcsfield
  • necsfield
  • gtcsfield
  • ftecsfield
  • ltcsfield
  • ltecsfield

If, however, some custom cross-field validation is required, it can be done using a custom validation.

Why not just have cross-fields validation tags (i.e. only eqcsfield and not eqfield)?

The reason is efficiency. If you want to check a field within the same struct "eqfield" only has to find the field on the same struct (1 level). But, if we used "eqcsfield" it could be multiple levels down. Example: 

type Inner struct {
	StartDate time.Time
}

type Outer struct {
	InnerStructField *Inner
	CreatedAt time.Time      `validate:"ltecsfield=InnerStructField.StartDate"`
}

now := time.Now()

inner := &Inner{
	StartDate: now,
}

outer := &Outer{
	InnerStructField: inner,
	CreatedAt: now,
}

errs := validate.Struct(outer)

// NOTE: when calling validate.Struct(val) topStruct will be the top level struct passed
//       into the function
//       when calling validate.FieldWithValue(val, field, tag) val will be
//       whatever you pass, struct, field...
//       when calling validate.Field(field, tag) val will be nil

Multiple Validators

Multiple validators on a field will process in the order defined. Example: 

type Test struct {
	Field `validate:"max=10,min=1"`
}

// max will be checked then min

Bad Validator definitions are not handled by the library. Example: 

type Test struct {
	Field `validate:"min=10,max=0"`
}

// this definition of min max will never succeed

Using Validator Tags

Baked In Cross-Field validation only compares fields on the same struct. If Cross-Field + Cross-Struct validation is needed you should implement your own custom validator.

Comma (",") is the default separator of validation tags. If you wish to have a comma included within the parameter (i.e. excludesall=,) you will need to use the UTF-8 hex representation 0x2C, which is replaced in the code as a comma, so the above will become excludesall=0x2C. 

type Test struct {
	Field `validate:"excludesall=,"`    // BAD! Do not include a comma.
	Field `validate:"excludesall=0x2C"` // GOOD! Use the UTF-8 hex representation.
}

Pipe ("|") is the default separator of validation tags. If you wish to have a pipe included within the parameter i.e. excludesall=| you will need to use the UTF-8 hex representation 0x7C, which is replaced in the code as a pipe, so the above will become excludesall=0x7C 

type Test struct {
	Field `validate:"excludesall=|"`    // BAD! Do not include a a pipe!
	Field `validate:"excludesall=0x7C"` // GOOD! Use the UTF-8 hex representation.
}

Baked In Validators and Tags

Here is a list of the current built in validators:

Skip Field

Tells the validation to skip this struct field; this is particularly handy in ignoring embedded structs from being validated. (Usage: -) 

Usage: -

Or Operator

This is the 'or' operator allowing multiple validators to be used and accepted. (Usage: rbg|rgba) <-- this would allow either rgb or rgba colors to be accepted. This can also be combined with 'and' for example ( Usage: omitempty,rgb|rgba) 

Usage: |

StructOnly

When a field that is a nested struct is encountered, and contains this flag any validation on the nested struct will be run, but none of the nested struct fields will be validated. This is usefull if inside of you program you know the struct will be valid, but need to verify it has been assigned. NOTE: only "required" and "omitempty" can be used on a struct itself. 

Usage: structonly

NoStructLevel

Same as structonly tag except that any struct level validations will not run. 

Usage: nostructlevel

Exists

Is a special tag without a validation function attached. It is used when a field is a Pointer, Interface or Invalid and you wish to validate that it exists. Example: want to ensure a bool exists if you define the bool as a pointer and use exists it will ensure there is a value; couldn't use required as it would fail when the bool was false. exists will fail is the value is a Pointer, Interface or Invalid and is nil. 

Usage: exists

Omit Empty

Allows conditional validation, for example if a field is not set with a value (Determined by the "required" validator) then other validation such as min or max won't run, but if a value is set validation will run. 

Usage: omitempty

Dive

This tells the validator to dive into a slice, array or map and validate that level of the slice, array or map with the validation tags that follow. Multidimensional nesting is also supported, each level you wish to dive will require another dive tag. 

Usage: dive

Example #1 

[][]string with validation tag "gt=0,dive,len=1,dive,required"
// gt=0 will be applied to []
// len=1 will be applied to []string
// required will be applied to string

Example #2 

[][]string with validation tag "gt=0,dive,dive,required"
// gt=0 will be applied to []
// []string will be spared validation
// required will be applied to string

Required

This validates that the value is not the data types default zero value. For numbers ensures value is not zero. For strings ensures value is not "". For slices, maps, pointers, interfaces, channels and functions ensures the value is not nil. 

Usage: required

Length

For numbers, max will ensure that the value is equal to the parameter given. For strings, it checks that the string length is exactly that number of characters. For slices, arrays, and maps, validates the number of items. 

Usage: len=10

Maximum

For numbers, max will ensure that the value is less than or equal to the parameter given. For strings, it checks that the string length is at most that number of characters. For slices, arrays, and maps, validates the number of items. 

Usage: max=10

Mininum

For numbers, min will ensure that the value is greater or equal to the parameter given. For strings, it checks that the string length is at least that number of characters. For slices, arrays, and maps, validates the number of items. 

Usage: min=10

Equals

For strings & numbers, eq will ensure that the value is equal to the parameter given. For slices, arrays, and maps, validates the number of items. 

Usage: eq=10

Not Equal

For strings & numbers, ne will ensure that the value is not equal to the parameter given. For slices, arrays, and maps, validates the number of items. 

Usage: ne=10

Greater Than

For numbers, this will ensure that the value is greater than the parameter given. For strings, it checks that the string length is greater than that number of characters. For slices, arrays and maps it validates the number of items.

Example #1 

Usage: gt=10

Example #2 (time.Time)

For time.Time ensures the time value is greater than time.Now.UTC(). 

Usage: gt

Greater Than or Equal

Same as 'min' above. Kept both to make terminology with 'len' easier.

Example #1 

Usage: gte=10

Example #2 (time.Time)

For time.Time ensures the time value is greater than or equal to time.Now.UTC(). 

Usage: gte

Less Than

For numbers, this will ensure that the value is less than the parameter given. For strings, it checks that the string length is less than that number of characters. For slices, arrays, and maps it validates the number of items.

Example #1 

Usage: lt=10

Example #2 (time.Time) For time.Time ensures the time value is less than time.Now.UTC(). 

Usage: lt

Less Than or Equal

Same as 'max' above. Kept both to make terminology with 'len' easier.

Example #1 

Usage: lte=10

Example #2 (time.Time)

For time.Time ensures the time value is less than or equal to time.Now.UTC(). 

Usage: lte

Field Equals Another Field

This will validate the field value against another fields value either within a struct or passed in field.

Example #1: 

// Validation on Password field using:
Usage: eqfield=ConfirmPassword

Example #2: 

// Validating by field:
validate.FieldWithValue(password, confirmpassword, "eqfield")

Field Equals Another Field (relative)

This does the same as eqfield except that it validates the field provided relative to the top level struct. 

Usage: eqcsfield=InnerStructField.Field)

Field Does Not Equal Another Field

This will validate the field value against another fields value either within a struct or passed in field.

Examples: 

// Confirm two colors are not the same:
//
// Validation on Color field:
Usage: nefield=Color2

// Validating by field:
validate.FieldWithValue(color1, color2, "nefield")

Field Does Not Equal Another Field (relative)

This does the same as nefield except that it validates the field provided relative to the top level struct. 

Usage: necsfield=InnerStructField.Field

Field Greater Than Another Field

Only valid for Numbers and time.Time types, this will validate the field value against another fields value either within a struct or passed in field. usage examples are for validation of a Start and End date:

Example #1: 

// Validation on End field using:
validate.Struct Usage(gtfield=Start)

Example #2: 

// Validating by field:
validate.FieldWithValue(start, end, "gtfield")

Field Greater Than Another Relative Field

This does the same as gtfield except that it validates the field provided relative to the top level struct. 

Usage: gtcsfield=InnerStructField.Field

Field Greater Than or Equal To Another Field

Only valid for Numbers and time.Time types, this will validate the field value against another fields value either within a struct or passed in field. usage examples are for validation of a Start and End date:

Example #1: 

// Validation on End field using:
validate.Struct Usage(gtefield=Start)

Example #2: 

// Validating by field:
validate.FieldWithValue(start, end, "gtefield")

Field Greater Than or Equal To Another Relative Field

This does the same as gtefield except that it validates the field provided relative to the top level struct. 

Usage: gtecsfield=InnerStructField.Field

Less Than Another Field

Only valid for Numbers and time.Time types, this will validate the field value against another fields value either within a struct or passed in field. usage examples are for validation of a Start and End date:

Example #1: 

// Validation on End field using:
validate.Struct Usage(ltfield=Start)

Example #2: 

// Validating by field:
validate.FieldWithValue(start, end, "ltfield")

Less Than Another Relative Field

This does the same as ltfield except that it validates the field provided relative to the top level struct. 

Usage: ltcsfield=InnerStructField.Field

Less Than or Equal To Another Field

Only valid for Numbers and time.Time types, this will validate the field value against another fields value either within a struct or passed in field. usage examples are for validation of a Start and End date:

Example #1: 

// Validation on End field using:
validate.Struct Usage(ltefield=Start)

Example #2: 

// Validating by field:
validate.FieldWithValue(start, end, "ltefield")

Less Than or Equal To Another Relative Field

This does the same as ltefield except that it validates the field provided relative to the top level struct. 

Usage: ltecsfield=InnerStructField.Field

Alpha Only

This validates that a string value contains alpha characters only 

Usage: alpha

Alphanumeric

This validates that a string value contains alphanumeric characters only 

Usage: alphanum

Numeric

This validates that a string value contains a basic numeric value. basic excludes exponents etc... 

Usage: numeric

Hexadecimal String

This validates that a string value contains a valid hexadecimal. 

Usage: hexadecimal

Hexcolor String

This validates that a string value contains a valid hex color including hashtag (#) 

Usage: hexcolor

RGB String

This validates that a string value contains a valid rgb color 

Usage: rgb

RGBA String

This validates that a string value contains a valid rgba color 

Usage: rgba

HSL String

This validates that a string value contains a valid hsl color 

Usage: hsl

HSLA String

This validates that a string value contains a valid hsla color 

Usage: hsla

E-mail String

This validates that a string value contains a valid email This may not conform to all possibilities of any rfc standard, but neither does any email provider accept all posibilities. 

Usage: email

URL String

This validates that a string value contains a valid url This will accept any url the golang request uri accepts but must contain a schema for example http:// or rtmp:// 

Usage: url

URI String

This validates that a string value contains a valid uri This will accept any uri the golang request uri accepts 

Usage: uri

Base64 String

This validates that a string value contains a valid base64 value. Although an empty string is valid base64 this will report an empty string as an error, if you wish to accept an empty string as valid you can use this with the omitempty tag. 

Usage: base64

Contains

This validates that a string value contains the substring value. 

Usage: contains=@

Contains Any

This validates that a string value contains any Unicode code points in the substring value. 

Usage: containsany=!@#?

Contains Rune

This validates that a string value contains the supplied rune value. 

Usage: containsrune=@

Excludes

This validates that a string value does not contain the substring value. 

Usage: excludes=@

Excludes All

This validates that a string value does not contain any Unicode code points in the substring value. 

Usage: excludesall=!@#?

Excludes Rune

This validates that a string value does not contain the supplied rune value. 

Usage: excludesrune=@

International Standard Book Number

This validates that a string value contains a valid isbn10 or isbn13 value. 

Usage: isbn

International Standard Book Number 10

This validates that a string value contains a valid isbn10 value. 

Usage: isbn10

International Standard Book Number 13

This validates that a string value contains a valid isbn13 value. 

Usage: isbn13

Universally Unique Identifier UUID

This validates that a string value contains a valid UUID. 

Usage: uuid

Universally Unique Identifier UUID v3

This validates that a string value contains a valid version 3 UUID. 

Usage: uuid3

Universally Unique Identifier UUID v4

This validates that a string value contains a valid version 4 UUID. 

Usage: uuid4

Universally Unique Identifier UUID v5

This validates that a string value contains a valid version 5 UUID. 

Usage: uuid5

ASCII

This validates that a string value contains only ASCII characters. NOTE: if the string is blank, this validates as true. 

Usage: ascii

Printable ASCII

This validates that a string value contains only printable ASCII characters. NOTE: if the string is blank, this validates as true. 

Usage: asciiprint

Multi-Byte Characters

This validates that a string value contains one or more multibyte characters. NOTE: if the string is blank, this validates as true. 

Usage: multibyte

Data URL

This validates that a string value contains a valid DataURI. NOTE: this will also validate that the data portion is valid base64 

Usage: datauri

Latitude

This validates that a string value contains a valid latitude. 

Usage: latitude

Longitude

This validates that a string value contains a valid longitude. 

Usage: longitude

Social Security Number SSN

This validates that a string value contains a valid U.S. Social Security Number. 

Usage: ssn

Internet Protocol Address IP

This validates that a string value contains a valid IP Adress. 

Usage: ip

Internet Protocol Address IPv4

This validates that a string value contains a valid v4 IP Adress. 

Usage: ipv4

Internet Protocol Address IPv6

This validates that a string value contains a valid v6 IP Adress. 

Usage: ipv6

Classless Inter-Domain Routing CIDR

This validates that a string value contains a valid CIDR Adress. 

Usage: cidr

Classless Inter-Domain Routing CIDRv4

This validates that a string value contains a valid v4 CIDR Adress. 

Usage: cidrv4

Classless Inter-Domain Routing CIDRv6

This validates that a string value contains a valid v6 CIDR Adress. 

Usage: cidrv6

Transmission Control Protocol Address TCP

This validates that a string value contains a valid resolvable TCP Adress. 

Usage: tcp_addr

Transmission Control Protocol Address TCPv4

This validates that a string value contains a valid resolvable v4 TCP Adress. 

Usage: tcp4_addr

Transmission Control Protocol Address TCPv6

This validates that a string value contains a valid resolvable v6 TCP Adress. 

Usage: tcp6_addr

User Datagram Protocol Address UDP

This validates that a string value contains a valid resolvable UDP Adress. 

Usage: udp_addr

User Datagram Protocol Address UDPv4

This validates that a string value contains a valid resolvable v4 UDP Adress. 

Usage: udp4_addr

User Datagram Protocol Address UDPv6

This validates that a string value contains a valid resolvable v6 UDP Adress. 

Usage: udp6_addr

Internet Protocol Address IP

This validates that a string value contains a valid resolvable IP Adress. 

Usage: ip_addr

Internet Protocol Address IPv4

This validates that a string value contains a valid resolvable v4 IP Adress. 

Usage: ip4_addr

Internet Protocol Address IPv6

This validates that a string value contains a valid resolvable v6 IP Adress. 

Usage: ip6_addr

Unix domain socket end point Address

This validates that a string value contains a valid Unix Adress. 

Usage: unix_addr

Media Access Control Address MAC

This validates that a string value contains a valid MAC Adress. 

Usage: mac

Note: See Go's ParseMAC for accepted formats and types: 

http://golang.org/src/net/mac.go?s=866:918#L29

Alias Validators and Tags

NOTE: When returning an error, the tag returned in "FieldError" will be the alias tag unless the dive tag is part of the alias. Everything after the dive tag is not reported as the alias tag. Also, the "ActualTag" in the before case will be the actual tag within the alias that failed.

Here is a list of the current built in alias tags: 

"iscolor"
	alias is "hexcolor|rgb|rgba|hsl|hsla" (Usage: iscolor)

Validator notes: 

regex
	a regex validator won't be added because commas and = signs can be part
	of a regex which conflict with the validation definitions. Although
	workarounds can be made, they take away from using pure regex's.
	Furthermore it's quick and dirty but the regex's become harder to
	maintain and are not reusable, so it's as much a programming philosiphy
	as anything.

	In place of this new validator functions should be created; a regex can
	be used within the validator function and even be precompiled for better
	efficiency within regexes.go.

	And the best reason, you can submit a pull request and we can keep on
	adding to the validation library of this package!

Panics

This package panics when bad input is provided, this is by design, bad code like that should not make it to production. 

type Test struct {
	TestField string `validate:"nonexistantfunction=1"`
}

t := &Test{
	TestField: "Test"
}

validate.Struct(t) // this will panic

Index

Examples

Constants

This section is empty.

Variables

This section is empty.

Functions

func Contains 

func Contains(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

Contains is the validation function for validating that the field's value contains the text specified within the param. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func ContainsAny 

func ContainsAny(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

ContainsAny is the validation function for validating that the field's value contains any of the characters specified within the param. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func ContainsRune 

func ContainsRune(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

ContainsRune is the validation function for validating that the field's value contains the rune specified within the param. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func Excludes 

func Excludes(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

Excludes is the validation function for validating that the field's value does not contain the text specified within the param. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func ExcludesAll 

func ExcludesAll(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

ExcludesAll is the validation function for validating that the field's value does not contain any of the characters specified within the param. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func ExcludesRune 

func ExcludesRune(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

ExcludesRune is the validation function for validating that the field's value does not contain the rune specified within the param. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func HasLengthOf 

func HasLengthOf(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

HasLengthOf is the validation function for validating if the current field's value is equal to the param's value. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func HasMaxOf 

func HasMaxOf(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

HasMaxOf is the validation function for validating if the current field's value is less than or equal to the param's value. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func HasMinOf 

func HasMinOf(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

HasMinOf is the validation function for validating if the current field's value is greater than or equal to the param's value. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func HasMultiByteCharacter 

func HasMultiByteCharacter(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

HasMultiByteCharacter is the validation function for validating if the field's value has a multi byte character. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func HasValue 

func HasValue(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

HasValue is the validation function for validating if the current field's value is not the default static value. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsASCII 

func IsASCII(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsASCII is the validation function for validating if the field's value is a valid ASCII character. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsAlpha 

func IsAlpha(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsAlpha is the validation function for validating if the current field's value is a valid alpha value. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsAlphanum 

func IsAlphanum(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsAlphanum is the validation function for validating if the current field's value is a valid alphanumeric value. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsBase64 

func IsBase64(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsBase64 is the validation function for validating if the current field's value is a valid base 64. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsCIDR 

func IsCIDR(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsCIDR is the validation function for validating if the field's value is a valid v4 or v6 CIDR address. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsCIDRv4 

func IsCIDRv4(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsCIDRv4 is the validation function for validating if the field's value is a valid v4 CIDR address. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsCIDRv6 

func IsCIDRv6(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsCIDRv6 is the validation function for validating if the field's value is a valid v6 CIDR address. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsDataURI 

func IsDataURI(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsDataURI is the validation function for validating if the field's value is a valid data URI. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsEmail 

func IsEmail(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsEmail is the validation function for validating if the current field's value is a valid email address. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsEq 

func IsEq(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsEq is the validation function for validating if the current field's value is equal to the param's value. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsEqCrossStructField 

func IsEqCrossStructField(v *Validate, topStruct reflect.Value, current reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsEqCrossStructField is the validation function for validating that the current field's value is equal to the field, within a separate struct, specified by the param's value. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsEqField 

func IsEqField(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsEqField is the validation function for validating if the current field's value is equal to the field specified by the param's value. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsGt 

func IsGt(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsGt is the validation function for validating if the current field's value is greater than the param's value. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsGtCrossStructField 

func IsGtCrossStructField(v *Validate, topStruct reflect.Value, current reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsGtCrossStructField is the validation function for validating if the current field's value is greater than the field, within a separate struct, specified by the param's value. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsGtField 

func IsGtField(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsGtField is the validation function for validating if the current field's value is greater than the field specified by the param's value. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsGte 

func IsGte(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsGte is the validation function for validating if the current field's value is greater than or equal to the param's value. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsGteCrossStructField 

func IsGteCrossStructField(v *Validate, topStruct reflect.Value, current reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsGteCrossStructField is the validation function for validating if the current field's value is greater than or equal to the field, within a separate struct, specified by the param's value. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsGteField 

func IsGteField(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsGteField is the validation function for validating if the current field's value is greater than or equal to the field specified by the param's value. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsHEXColor 

func IsHEXColor(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsHEXColor is the validation function for validating if the current field's value is a valid HEX color. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsHSL 

func IsHSL(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsHSL is the validation function for validating if the current field's value is a valid HSL color. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsHSLA 

func IsHSLA(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsHSLA is the validation function for validating if the current field's value is a valid HSLA color. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsHexadecimal 

func IsHexadecimal(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsHexadecimal is the validation function for validating if the current field's value is a valid hexadecimal. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsIP 

func IsIP(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsIP is the validation function for validating if the field's value is a valid v4 or v6 IP address. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsIP4AddrResolvable 

func IsIP4AddrResolvable(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsIP4AddrResolvable is the validation function for validating if the field's value is a resolvable ip4 address. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsIP6AddrResolvable 

func IsIP6AddrResolvable(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsIP6AddrResolvable is the validation function for validating if the field's value is a resolvable ip6 address. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsIPAddrResolvable 

func IsIPAddrResolvable(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsIPAddrResolvable is the validation function for validating if the field's value is a resolvable ip address. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsIPv4 

func IsIPv4(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsIPv4 is the validation function for validating if a value is a valid v4 IP address. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsIPv6 

func IsIPv6(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsIPv6 is the validation function for validating if the field's value is a valid v6 IP address. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsISBN 

func IsISBN(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsISBN is the validation function for validating if the field's value is a valid v10 or v13 ISBN. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsISBN10 

func IsISBN10(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsISBN10 is the validation function for validating if the field's value is a valid v10 ISBN. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsISBN13 

func IsISBN13(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsISBN13 is the validation function for validating if the field's value is a valid v13 ISBN. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsLatitude 

func IsLatitude(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsLatitude is the validation function for validating if the field's value is a valid latitude coordinate. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsLongitude 

func IsLongitude(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsLongitude is the validation function for validating if the field's value is a valid longitude coordinate. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsLt 

func IsLt(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsLt is the validation function for validating if the current field's value is less than the param's value. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsLtCrossStructField 

func IsLtCrossStructField(v *Validate, topStruct reflect.Value, current reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsLtCrossStructField is the validation function for validating if the current field's value is less than the field, within a separate struct, specified by the param's value. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsLtField 

func IsLtField(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsLtField is the validation function for validating if the current field's value is less than the field specified by the param's value. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsLte 

func IsLte(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsLte is the validation function for validating if the current field's value is less than or equal to the param's value. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsLteCrossStructField 

func IsLteCrossStructField(v *Validate, topStruct reflect.Value, current reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsLteCrossStructField is the validation function for validating if the current field's value is less than or equal to the field, within a separate struct, specified by the param's value. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsLteField 

func IsLteField(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsLteField is the validation function for validating if the current field's value is less than or equal to the field specified by the param's value. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsMAC 

func IsMAC(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsMAC is the validation function for validating if the field's value is a valid MAC address. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsNe 

func IsNe(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsNe is the validation function for validating that the field's value does not equal the provided param value. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsNeCrossStructField 

func IsNeCrossStructField(v *Validate, topStruct reflect.Value, current reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsNeCrossStructField is the validation function for validating that the current field's value is not equal to the field, within a separate struct, specified by the param's value. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsNeField 

func IsNeField(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsNeField is the validation function for validating if the current field's value is not equal to the field specified by the param's value. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsNumber 

func IsNumber(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsNumber is the validation function for validating if the current field's value is a valid number. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsNumeric 

func IsNumeric(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsNumeric is the validation function for validating if the current field's value is a valid numeric value. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsPrintableASCII 

func IsPrintableASCII(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsPrintableASCII is the validation function for validating if the field's value is a valid printable ASCII character. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsRGB 

func IsRGB(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsRGB is the validation function for validating if the current field's value is a valid RGB color. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsRGBA 

func IsRGBA(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsRGBA is the validation function for validating if the current field's value is a valid RGBA color. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsSSN 

func IsSSN(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsSSN is the validation function for validating if the field's value is a valid SSN. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsTCP4AddrResolvable 

func IsTCP4AddrResolvable(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsTCP4AddrResolvable is the validation function for validating if the field's value is a resolvable tcp4 address. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsTCP6AddrResolvable 

func IsTCP6AddrResolvable(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsTCP6AddrResolvable is the validation function for validating if the field's value is a resolvable tcp6 address. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsTCPAddrResolvable 

func IsTCPAddrResolvable(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsTCPAddrResolvable is the validation function for validating if the field's value is a resolvable tcp address. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsUDP4AddrResolvable 

func IsUDP4AddrResolvable(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsUDP4AddrResolvable is the validation function for validating if the field's value is a resolvable udp4 address. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsUDP6AddrResolvable 

func IsUDP6AddrResolvable(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsUDP6AddrResolvable is the validation function for validating if the field's value is a resolvable udp6 address. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsUDPAddrResolvable 

func IsUDPAddrResolvable(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsUDPAddrResolvable is the validation function for validating if the field's value is a resolvable udp address. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsURI 

func IsURI(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsURI is the validation function for validating if the current field's value is a valid URI. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsURL 

func IsURL(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsURL is the validation function for validating if the current field's value is a valid URL. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsUUID 

func IsUUID(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsUUID is the validation function for validating if the field's value is a valid UUID of any version. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsUUID3 

func IsUUID3(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsUUID3 is the validation function for validating if the field's value is a valid v3 UUID. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsUUID4 

func IsUUID4(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsUUID4 is the validation function for validating if the field's value is a valid v4 UUID. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsUUID5 

func IsUUID5(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsUUID5 is the validation function for validating if the field's value is a valid v5 UUID. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

func IsUnixAddrResolvable 

func IsUnixAddrResolvable(v *Validate, topStruct reflect.Value, currentStructOrField reflect.Value, field reflect.Value, fieldType reflect.Type, fieldKind reflect.Kind, param string) bool

IsUnixAddrResolvable is the validation function for validating if the field's value is a resolvable unix address. NOTE: This is exposed for use within your own custom functions and not intended to be called directly.

Types

type Config 

type Config struct {
	TagName      string
	FieldNameTag string
}

Config contains the options that a Validator instance will use. It is passed to the New() function

type CustomTypeFunc 

type CustomTypeFunc func(field reflect.Value) interface{}

CustomTypeFunc allows for overriding or adding custom field type handler functions field = field value of the type to return a value to be validated example Valuer from sql drive see https://golang.org/src/database/sql/driver/types.go?s=1210:1293#L29

type FieldError 

type FieldError struct {
	FieldNamespace string
	NameNamespace  string
	Field          string
	Name           string
	Tag            string
	ActualTag      string
	Kind           reflect.Kind
	Type           reflect.Type
	Param          string
	Value          interface{}
}

FieldError contains a single field's validation error along with other properties that may be needed for error message creation

type Func 

type Func func(v *Validate, topStruct reflect.Value, currentStruct reflect.Value, field reflect.Value, fieldtype reflect.Type, fieldKind reflect.Kind, param string) bool

Func accepts all values needed for file and cross field validation v = validator instance, needed but some built in functions for it's custom types topStruct = top level struct when validating by struct otherwise nil currentStruct = current level struct when validating by struct otherwise optional comparison value field = field value for validation param = parameter used in validation i.e. gt=0 param would be 0

type StructLevel 

type StructLevel struct {
	TopStruct     reflect.Value
	CurrentStruct reflect.Value
	// contains filtered or unexported fields
}

StructLevel contains all of the information and helper methods for reporting errors during struct level validation

func (*StructLevel) ReportError 

func (sl *StructLevel) ReportError(field reflect.Value, fieldName string, customName string, tag string)

ReportError reports an error just by passing the field and tag information NOTE: tag can be an existing validation tag or just something you make up and precess on the flip side it's up to you.

func (*StructLevel) ReportValidationErrors 

func (sl *StructLevel) ReportValidationErrors(relativeKey string, errs ValidationErrors)

ReportValidationErrors accepts the key relative to the top level struct and validatin errors. Example: had a triple nested struct User, ContactInfo, Country and ran errs := validate.Struct(country) from within a User struct level validation would call this method like so: ReportValidationErrors("ContactInfo.", errs) NOTE: relativeKey can contain both the Field Relative and Custom name relative paths i.e. ReportValidationErrors("ContactInfo.|cInfo", errs) where cInfo represents say the JSON name of the relative path; this will be split into 2 variables in the next valiator version.

type StructLevelFunc 

type StructLevelFunc func(v *Validate, structLevel *StructLevel)

StructLevelFunc accepts all values needed for struct level validation

type Validate 

type Validate struct {
	// contains filtered or unexported fields
}

Validate contains the validator settings passed in using the Config struct

Example (Field) 
// This should be stored somewhere globally
var validate *validator.Validate

config := &validator.Config{TagName: "validate"}

validate = validator.New(config)

i := 0
errs := validate.Field(i, "gt=1,lte=10")
err := errs.(validator.ValidationErrors)[""]
fmt.Println(err.Field)
fmt.Println(err.Tag)
fmt.Println(err.Kind) // NOTE: Kind and Type can be different i.e. time Kind=struct and Type=time.Time
fmt.Println(err.Type)
fmt.Println(err.Param)
fmt.Println(err.Value)

Output:


gt
int
int
1
0
Example (New) 
config := &validator.Config{TagName: "validate"}

validator.New(config)

Output:
Example (Struct) 
// This should be stored somewhere globally
var validate *validator.Validate

config := &validator.Config{TagName: "validate"}

validate = validator.New(config)

type ContactInformation struct {
	Phone  string `validate:"required"`
	Street string `validate:"required"`
	City   string `validate:"required"`
}

type User struct {
	Name               string `validate:"required,excludesall=!@#$%^&*()_+-=:;?/0x2C"` // 0x2C = comma (,)
	Age                int8   `validate:"required,gt=0,lt=150"`
	Email              string `validate:"email"`
	ContactInformation []*ContactInformation
}

contactInfo := &ContactInformation{
	Street: "26 Here Blvd.",
	City:   "Paradeso",
}

user := &User{
	Name:               "Joey Bloggs",
	Age:                31,
	Email:              "joeybloggs@gmail.com",
	ContactInformation: []*ContactInformation{contactInfo},
}

errs := validate.Struct(user)
for _, v := range errs.(validator.ValidationErrors) {
	fmt.Println(v.Field) // Phone
	fmt.Println(v.Tag)   // required
	//... and so forth
	

Output:

func New 

func New(config *Config) *Validate

New creates a new Validate instance for use.

func (*Validate) ExtractType 

func (v *Validate) ExtractType(current reflect.Value) (reflect.Value, reflect.Kind)

ExtractType gets the actual underlying type of field value. It will dive into pointers, customTypes and return you the underlying value and it's kind. it is exposed for use within you Custom Functions

func (*Validate) Field 

func (v *Validate) Field(field interface{}, tag string) error

Field validates a single field using tag style validation and returns nil or ValidationErrors as type error. You will need to assert the error if it's not nil i.e. err.(validator.ValidationErrors) to access the map of errors. NOTE: it returns ValidationErrors instead of a single FieldError because this can also validate Array, Slice and maps fields which may contain more than one error

func (*Validate) FieldWithValue 

func (v *Validate) FieldWithValue(val interface{}, field interface{}, tag string) error

FieldWithValue validates a single field, against another fields value using tag style validation and returns nil or ValidationErrors. You will need to assert the error if it's not nil i.e. err.(validator.ValidationErrors) to access the map of errors. NOTE: it returns ValidationErrors instead of a single FieldError because this can also validate Array, Slice and maps fields which may contain more than one error

func (*Validate) GetStructFieldOK 

func (v *Validate) GetStructFieldOK(current reflect.Value, namespace string) (reflect.Value, reflect.Kind, bool)

GetStructFieldOK traverses a struct to retrieve a specific field denoted by the provided namespace and returns the field, field kind and whether is was successful in retrieving the field at all. NOTE: when not successful ok will be false, this can happen when a nested struct is nil and so the field could not be retrieved because it didn't exist.

func (*Validate) RegisterAliasValidation 

func (v *Validate) RegisterAliasValidation(alias, tags string)

RegisterAliasValidation registers a mapping of a single validationstag that defines a common or complex set of validation(s) to simplify adding validation to structs. NOTE: when returning an error the tag returned in FieldError will be the alias tag unless the dive tag is part of the alias; everything after the dive tag is not reported as the alias tag. Also the ActualTag in the before case will be the actual tag within the alias that failed. NOTE: this method is not thread-safe it is intended that these all be registered prior to any validation

func (*Validate) RegisterCustomTypeFunc 

func (v *Validate) RegisterCustomTypeFunc(fn CustomTypeFunc, types ...interface{})

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

func (*Validate) RegisterStructValidation 

func (v *Validate) RegisterStructValidation(fn StructLevelFunc, types ...interface{})

RegisterStructValidation registers a StructLevelFunc against a number of types NOTE: this method is not thread-safe it is intended that these all be registered prior to any validation

func (*Validate) RegisterValidation 

func (v *Validate) RegisterValidation(key string, fn Func) error

RegisterValidation adds a validation Func to a Validate's map of validators denoted by the key NOTE: if the key already exists, the previous validation function will be replaced. NOTE: this method is not thread-safe it is intended that these all be registered prior to any validation

func (*Validate) Struct 

func (v *Validate) Struct(current interface{}) error

Struct validates a structs exposed fields, and automatically validates nested structs, unless otherwise specified. it returns nil or ValidationErrors as error. You will need to assert the error if it's not nil i.e. err.(validator.ValidationErrors) to access the map of errors.

func (*Validate) StructExcept 

func (v *Validate) StructExcept(current interface{}, fields ...string) error

StructExcept validates all fields except the ones passed in. Fields may be provided in a namespaced fashion relative to the struct provided i.e. NestedStruct.Field or NestedArrayField[0].Struct.Name and returns nil or ValidationErrors as error You will need to assert the error if it's not nil i.e. err.(validator.ValidationErrors) to access the map of errors.

func (*Validate) StructPartial 

func (v *Validate) StructPartial(current interface{}, fields ...string) error

StructPartial validates the fields passed in only, ignoring all others. Fields may be provided in a namespaced fashion relative to the struct provided i.e. NestedStruct.Field or NestedArrayField[0].Struct.Name and returns nil or ValidationErrors as error You will need to assert the error if it's not nil i.e. err.(validator.ValidationErrors) to access the map of errors.

type ValidationErrors 

type ValidationErrors map[string]*FieldError

ValidationErrors is a type of map[string]*FieldError it exists to allow for multiple errors to be passed from this library and yet still subscribe to the error interface

func (ValidationErrors) Error 

func (ve ValidationErrors) Error() string

Error is intended for use in development + debugging and not intended to be a production error message. It allows ValidationErrors to subscribe to the Error interface. All information to create an error message specific to your application is contained within the FieldError found within the ValidationErrors map

Source Files

View all Source files

Directories

Path Synopsis
examples
custom
simple
struct-level

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