validator.v9: gopkg.in/go-playground/validator.v9 Index | Files | Directories

package validator

import "gopkg.in/go-playground/validator.v9"

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.

see more examples https://github.com/go-playground/validator/tree/v9/_examples

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 InvalidValidationError for bad validation input, 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 check if error is InvalidValidationError ( if necessary, most of the time it isn't ) type cast it to type ValidationErrors like so err.(validator.ValidationErrors).

Custom Validation Functions

Custom Validation functions can be added. Example:

// Structure
func customFunc(fl validator.FieldLevel) bool {

	if fl.Field().String() == "invalid" {
		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
- gtecsfield
- 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.VarWithValue(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 'or' validation tags deparator. 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 useful 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

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. dive has some sub-tags, 'keys' & 'endkeys', please see the Keys & EndKeys section just below.

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

Keys & EndKeys

These are to be used together directly after the dive tag and tells the validator that anything between 'keys' and 'endkeys' applies to the keys of a map and not the values; think of it like the 'dive' tag, but for map keys instead of values. Multidimensional nesting is also supported, each level you wish to validate will require another 'keys' and 'endkeys' tag. These tags are only valid for maps.

Usage: dive,keys,othertagvalidation(s),endkeys,valuevalidationtags

Example #1

map[string]string with validation tag "gt=0,dive,keys,eg=1|eq=2,endkeys,required"
// gt=0 will be applied to the map itself
// eg=1|eq=2 will be applied to the map keys
// required will be applied to map values

Example #2

map[[2]string]string with validation tag "gt=0,dive,keys,dive,eq=1|eq=2,endkeys,required"
// gt=0 will be applied to the map itself
// eg=1|eq=2 will be applied to each array element in the the map keys
// required will be applied to map values

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

Is Default

This validates that the value is the default value and is almost the opposite of required.

Usage: isdefault

Length

For numbers, length 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

Minimum

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

One Of

For strings, ints, and uints, oneof will ensure that the value is one of the values in the parameter. The parameter should be a list of values separated by whitespace. Values may be strings or numbers.

Usage: oneof=red green
       oneof=5 7 9

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.VarWithValue(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.VarWithValue(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.VarWithValue(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.VarWithValue(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.VarWithValue(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.VarWithValue(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

Unique

For arrays & slices, unique will ensure that there are no duplicates. For maps, unique will ensure that there are no duplicate values.

Usage: unique

Alpha Only

This validates that a string value contains ASCII alpha characters only

Usage: alpha

Alphanumeric

This validates that a string value contains ASCII alphanumeric characters only

Usage: alphanum

Alpha Unicode

This validates that a string value contains unicode alpha characters only

Usage: alphaunicode

Alphanumeric Unicode

This validates that a string value contains unicode alphanumeric characters only

Usage: alphanumunicode

Numeric

This validates that a string value contains a basic numeric value. basic excludes exponents etc... for integers or float it returns true.

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

File path

This validates that a string value contains a valid file path and that the file exists on the machine. This is done using os.Stat, which is a platform independent function.

Usage: file

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

Base64URL String

This validates that a string value contains a valid base64 URL safe value according the the RFC4648 spec. Although an empty string is a valid base64 URL safe value, 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: base64url

Bitcoin Address

This validates that a string value contains a valid bitcoin address. The format of the string is checked to ensure it matches one of the three formats P2PKH, P2SH and performs checksum validation.

Usage: btc_addr

Bitcoin Bech32 Address (segwit)

This validates that a string value contains a valid bitcoin Bech32 address as defined by bip-0173 (https://github.com/bitcoin/bips/blob/master/bip-0173.mediawiki) Special thanks to Pieter Wuille for providng reference implementations.

Usage: btc_addr_bech32

Ethereum Address

This validates that a string value contains a valid ethereum address. The format of the string is checked to ensure it matches the standard Ethereum address format Full validation is blocked by https://github.com/golang/crypto/pull/28

Usage: eth_addr

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: printascii

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 Address.

Usage: ip

Internet Protocol Address IPv4

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

Usage: ipv4

Internet Protocol Address IPv6

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

Usage: ipv6

Classless Inter-Domain Routing CIDR

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

Usage: cidr

Classless Inter-Domain Routing CIDRv4

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

Usage: cidrv4

Classless Inter-Domain Routing CIDRv6

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

Usage: cidrv6

Transmission Control Protocol Address TCP

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

Usage: tcp_addr

Transmission Control Protocol Address TCPv4

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

Usage: tcp4_addr

Transmission Control Protocol Address TCPv6

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

Usage: tcp6_addr

User Datagram Protocol Address UDP

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

Usage: udp_addr

User Datagram Protocol Address UDPv4

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

Usage: udp4_addr

User Datagram Protocol Address UDPv6

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

Usage: udp6_addr

Internet Protocol Address IP

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

Usage: ip_addr

Internet Protocol Address IPv4

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

Usage: ip4_addr

Internet Protocol Address IPv6

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

Usage: ip6_addr

Unix domain socket end point Address

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

Usage: unix_addr

Media Access Control Address MAC

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

Usage: mac

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

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

Hostname RFC 952

This validates that a string value is a valid Hostname according to RFC 952 https://tools.ietf.org/html/rfc952

Usage: hostname

Hostname RFC 1123

This validates that a string value is a valid Hostname according to RFC 1123 https://tools.ietf.org/html/rfc1123

Usage: hostname_rfc1123 or if you want to continue to use 'hostname' in your tags, create an alias.

Full Qualified Domain Name (FQDN)

This validates that a string value contains a valid FQDN.

Usage: fqdn

HTML Tags

This validates that a string value appears to be an HTML element tag including those described at https://developer.mozilla.org/en-US/docs/Web/HTML/Element

Usage: html

HTML Encoded

This validates that a string value is a proper character reference in decimal or hexadecimal format

Usage: html_encoded

URL Encoded

This validates that a string value is percent-encoded (URL encoded) according to https://tools.ietf.org/html/rfc3986#section-2.1

Usage: url_encoded

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 philosophy
	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

Package Files

baked_in.go cache.go doc.go errors.go field_level.go regexes.go struct_level.go translations.go util.go validator.go validator_instance.go

type CustomTypeFunc Uses

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 Uses

type FieldError interface {

    // returns the validation tag that failed. if the
    // validation was an alias, this will return the
    // alias name and not the underlying tag that failed.
    //
    // eg. alias "iscolor": "hexcolor|rgb|rgba|hsl|hsla"
    // will return "iscolor"
    Tag() string

    // returns the validation tag that failed, even if an
    // alias the actual tag within the alias will be returned.
    // If an 'or' validation fails the entire or will be returned.
    //
    // eg. alias "iscolor": "hexcolor|rgb|rgba|hsl|hsla"
    // will return "hexcolor|rgb|rgba|hsl|hsla"
    ActualTag() string

    // returns the namespace for the field error, with the tag
    // name taking precedence over the fields actual name.
    //
    // eg. JSON name "User.fname"
    //
    // See StructNamespace() for a version that returns actual names.
    //
    // NOTE: this field can be blank when validating a single primitive field
    // using validate.Field(...) as there is no way to extract it's name
    Namespace() string

    // returns the namespace for the field error, with the fields
    // actual name.
    //
    // eq. "User.FirstName" see Namespace for comparison
    //
    // NOTE: this field can be blank when validating a single primitive field
    // using validate.Field(...) as there is no way to extract it's name
    StructNamespace() string

    // returns the fields name with the tag name taking precedence over the
    // fields actual name.
    //
    // eq. JSON name "fname"
    // see StructField for comparison
    Field() string

    // returns the fields actual name from the struct, when able to determine.
    //
    // eq.  "FirstName"
    // see Field for comparison
    StructField() string

    // returns the actual fields value in case needed for creating the error
    // message
    Value() interface{}

    // returns the param value, in string form for comparison; this will also
    // help with generating an error message
    Param() string

    // Kind returns the Field's reflect Kind
    //
    // eg. time.Time's kind is a struct
    Kind() reflect.Kind

    // Type returns the Field's reflect Type
    //
    // // eg. time.Time's type is time.Time
    Type() reflect.Type

    // returns the FieldError's translated error
    // from the provided 'ut.Translator' and registered 'TranslationFunc'
    //
    // NOTE: is not registered translation can be found it returns the same
    // as calling fe.Error()
    Translate(ut ut.Translator) string
}

FieldError contains all functions to get error details

type FieldLevel Uses

type FieldLevel interface {

    // returns the top level struct, if any
    Top() reflect.Value

    // returns the current fields parent struct, if any or
    // the comparison value if called 'VarWithValue'
    Parent() reflect.Value

    // returns current field for validation
    Field() reflect.Value

    // returns the field's name with the tag
    // name taking precedence over the fields actual name.
    FieldName() string

    // returns the struct field's name
    StructFieldName() string

    // returns param for validation against current field
    Param() string

    // 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.
    ExtractType(field reflect.Value) (value reflect.Value, kind reflect.Kind, nullable bool)

    // traverses the parent struct to retrieve a specific field denoted by the provided namespace
    // in the param 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.
    GetStructFieldOK() (reflect.Value, reflect.Kind, bool)
}

FieldLevel contains all the information and helper functions to validate a field

type FilterFunc Uses

type FilterFunc func(ns []byte) bool

FilterFunc is the type used to filter fields using StructFiltered(...) function. returning true results in the field being filtered/skiped from validation

type Func Uses

type Func func(fl FieldLevel) bool

Func accepts a FieldLevel interface for all validation needs. The return value should be true when validation succeeds.

type FuncCtx Uses

type FuncCtx func(ctx context.Context, fl FieldLevel) bool

FuncCtx accepts a context.Context and FieldLevel interface for all validation needs. The return value should be true when validation succeeds.

type InvalidValidationError Uses

type InvalidValidationError struct {
    Type reflect.Type
}

InvalidValidationError describes an invalid argument passed to `Struct`, `StructExcept`, StructPartial` or `Field`

func (*InvalidValidationError) Error Uses

func (e *InvalidValidationError) Error() string

Error returns InvalidValidationError message

type RegisterTranslationsFunc Uses

type RegisterTranslationsFunc func(ut ut.Translator) error

RegisterTranslationsFunc allows for registering of translations for a 'ut.Translator' for use within the 'TranslationFunc'

type StructLevel Uses

type StructLevel interface {

    // returns the main validation object, in case one want to call validations internally.
    // this is so you don;t have to use anonymous functoins to get access to the validate
    // instance.
    Validator() *Validate

    // returns the top level struct, if any
    Top() reflect.Value

    // returns the current fields parent struct, if any
    Parent() reflect.Value

    // returns the current struct.
    Current() reflect.Value

    // 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.
    ExtractType(field reflect.Value) (value reflect.Value, kind reflect.Kind, nullable bool)

    // reports an error just by passing the field and tag information
    //
    // NOTES:
    //
    // fieldName and altName get appended to the existing namespace that
    // validator is on. eg. pass 'FirstName' or 'Names[0]' depending
    // on the nesting
    //
    // tag can be an existing validation tag or just something you make up
    // and process on the flip side it's up to you.
    ReportError(field interface{}, fieldName, structFieldName string, tag, param string)

    // reports an error just by passing ValidationErrors
    //
    // NOTES:
    //
    // relativeNamespace and relativeActualNamespace get appended to the
    // existing namespace that validator is on.
    // eg. pass 'User.FirstName' or 'Users[0].FirstName' depending
    // on the nesting. most of the time they will be blank, unless you validate
    // at a level lower the the current field depth
    ReportValidationErrors(relativeNamespace, relativeActualNamespace string, errs ValidationErrors)
}

StructLevel contains all the information and helper functions to validate a struct

type StructLevelFunc Uses

type StructLevelFunc func(sl StructLevel)

StructLevelFunc accepts all values needed for struct level validation

type StructLevelFuncCtx Uses

type StructLevelFuncCtx func(ctx context.Context, sl StructLevel)

StructLevelFuncCtx accepts all values needed for struct level validation but also allows passing of contextual validation information vi context.Context.

type TagNameFunc Uses

type TagNameFunc func(field reflect.StructField) string

TagNameFunc allows for adding of a custom tag name parser

type TranslationFunc Uses

type TranslationFunc func(ut ut.Translator, fe FieldError) string

TranslationFunc is the function type used to register or override custom translations

type Validate Uses

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

Validate contains the validator settings and cache

func New Uses

func New() *Validate

New returns a new instance of 'validate' with sane defaults.

func (*Validate) RegisterAlias Uses

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

RegisterAlias registers a mapping of a single validation tag that defines a common or complex set of validation(s) to simplify adding validation to structs.

NOTE: this function is not thread-safe it is intended that these all be registered prior to any validation

func (*Validate) RegisterCustomTypeFunc Uses

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 Uses

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) RegisterStructValidationCtx Uses

func (v *Validate) RegisterStructValidationCtx(fn StructLevelFuncCtx, types ...interface{})

RegisterStructValidationCtx registers a StructLevelFuncCtx against a number of types and allows passing of contextual validation information via context.Context.

NOTE: - this method is not thread-safe it is intended that these all be registered prior to any validation

func (*Validate) RegisterTagNameFunc Uses

func (v *Validate) RegisterTagNameFunc(fn TagNameFunc)

RegisterTagNameFunc registers a function to get alternate names for StructFields.

eg. to use the names which have been specified for JSON representations of structs, rather than normal Go field names:

validate.RegisterTagNameFunc(func(fld reflect.StructField) string {
    name := strings.SplitN(fld.Tag.Get("json"), ",", 2)[0]
    if name == "-" {
        return ""
    }
    return name
})

func (*Validate) RegisterTranslation Uses

func (v *Validate) RegisterTranslation(tag string, trans ut.Translator, registerFn RegisterTranslationsFunc, translationFn TranslationFunc) (err error)

RegisterTranslation registers translations against the provided tag.

func (*Validate) RegisterValidation Uses

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

RegisterValidation adds a validation with the given tag

NOTES: - if the key already exists, the previous validation function will be replaced. - this method is not thread-safe it is intended that these all be registered prior to any validation

func (*Validate) RegisterValidationCtx Uses

func (v *Validate) RegisterValidationCtx(tag string, fn FuncCtx) error

RegisterValidationCtx does the same as RegisterValidation on accepts a FuncCtx validation allowing context.Context validation support.

func (*Validate) SetTagName Uses

func (v *Validate) SetTagName(name string)

SetTagName allows for changing of the default tag name of 'validate'

func (*Validate) Struct Uses

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

Struct validates a structs exposed fields, and automatically validates nested structs, unless otherwise specified.

It returns InvalidValidationError for bad values passed in and nil or ValidationErrors as error otherwise. You will need to assert the error if it's not nil eg. err.(validator.ValidationErrors) to access the array of errors.

func (*Validate) StructCtx Uses

func (v *Validate) StructCtx(ctx context.Context, s interface{}) (err error)

StructCtx validates a structs exposed fields, and automatically validates nested structs, unless otherwise specified and also allows passing of context.Context for contextual validation information.

It returns InvalidValidationError for bad values passed in and nil or ValidationErrors as error otherwise. You will need to assert the error if it's not nil eg. err.(validator.ValidationErrors) to access the array of errors.

func (*Validate) StructExcept Uses

func (v *Validate) StructExcept(s 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

It returns InvalidValidationError for bad values passed in and nil or ValidationErrors as error otherwise. You will need to assert the error if it's not nil eg. err.(validator.ValidationErrors) to access the array of errors.

func (*Validate) StructExceptCtx Uses

func (v *Validate) StructExceptCtx(ctx context.Context, s interface{}, fields ...string) (err error)

StructExceptCtx validates all fields except the ones passed in and allows passing of contextual validation validation information via context.Context Fields may be provided in a namespaced fashion relative to the struct provided i.e. NestedStruct.Field or NestedArrayField[0].Struct.Name

It returns InvalidValidationError for bad values passed in and nil or ValidationErrors as error otherwise. You will need to assert the error if it's not nil eg. err.(validator.ValidationErrors) to access the array of errors.

func (*Validate) StructFiltered Uses

func (v *Validate) StructFiltered(s interface{}, fn FilterFunc) error

StructFiltered validates a structs exposed fields, that pass the FilterFunc check and automatically validates nested structs, unless otherwise specified.

It returns InvalidValidationError for bad values passed in and nil or ValidationErrors as error otherwise. You will need to assert the error if it's not nil eg. err.(validator.ValidationErrors) to access the array of errors.

func (*Validate) StructFilteredCtx Uses

func (v *Validate) StructFilteredCtx(ctx context.Context, s interface{}, fn FilterFunc) (err error)

StructFilteredCtx validates a structs exposed fields, that pass the FilterFunc check and automatically validates nested structs, unless otherwise specified and also allows passing of contextual validation information via context.Context

It returns InvalidValidationError for bad values passed in and nil or ValidationErrors as error otherwise. You will need to assert the error if it's not nil eg. err.(validator.ValidationErrors) to access the array of errors.

func (*Validate) StructPartial Uses

func (v *Validate) StructPartial(s 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 eg. NestedStruct.Field or NestedArrayField[0].Struct.Name

It returns InvalidValidationError for bad values passed in and nil or ValidationErrors as error otherwise. You will need to assert the error if it's not nil eg. err.(validator.ValidationErrors) to access the array of errors.

func (*Validate) StructPartialCtx Uses

func (v *Validate) StructPartialCtx(ctx context.Context, s interface{}, fields ...string) (err error)

StructPartialCtx validates the fields passed in only, ignoring all others and allows passing of contextual validation validation information via context.Context Fields may be provided in a namespaced fashion relative to the struct provided eg. NestedStruct.Field or NestedArrayField[0].Struct.Name

It returns InvalidValidationError for bad values passed in and nil or ValidationErrors as error otherwise. You will need to assert the error if it's not nil eg. err.(validator.ValidationErrors) to access the array of errors.

func (*Validate) Var Uses

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

Var validates a single variable using tag style validation. eg. var i int validate.Var(i, "gt=1,lt=10")

WARNING: a struct can be passed for validation eg. time.Time is a struct or if you have a custom type and have registered a custom type handler, so must allow it; however unforeseen validations will occur if trying to validate a struct that is meant to be passed to 'validate.Struct'

It returns InvalidValidationError for bad values passed in and nil or ValidationErrors as error otherwise. You will need to assert the error if it's not nil eg. err.(validator.ValidationErrors) to access the array of errors. validate Array, Slice and maps fields which may contain more than one error

func (*Validate) VarCtx Uses

func (v *Validate) VarCtx(ctx context.Context, field interface{}, tag string) (err error)

VarCtx validates a single variable using tag style validation and allows passing of contextual validation validation information via context.Context. eg. var i int validate.Var(i, "gt=1,lt=10")

WARNING: a struct can be passed for validation eg. time.Time is a struct or if you have a custom type and have registered a custom type handler, so must allow it; however unforeseen validations will occur if trying to validate a struct that is meant to be passed to 'validate.Struct'

It returns InvalidValidationError for bad values passed in and nil or ValidationErrors as error otherwise. You will need to assert the error if it's not nil eg. err.(validator.ValidationErrors) to access the array of errors. validate Array, Slice and maps fields which may contain more than one error

func (*Validate) VarWithValue Uses

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

VarWithValue validates a single variable, against another variable/field's value using tag style validation eg. s1 := "abcd" s2 := "abcd" validate.VarWithValue(s1, s2, "eqcsfield") // returns true

WARNING: a struct can be passed for validation eg. time.Time is a struct or if you have a custom type and have registered a custom type handler, so must allow it; however unforeseen validations will occur if trying to validate a struct that is meant to be passed to 'validate.Struct'

It returns InvalidValidationError for bad values passed in and nil or ValidationErrors as error otherwise. You will need to assert the error if it's not nil eg. err.(validator.ValidationErrors) to access the array of errors. validate Array, Slice and maps fields which may contain more than one error

func (*Validate) VarWithValueCtx Uses

func (v *Validate) VarWithValueCtx(ctx context.Context, field interface{}, other interface{}, tag string) (err error)

VarWithValueCtx validates a single variable, against another variable/field's value using tag style validation and allows passing of contextual validation validation information via context.Context. eg. s1 := "abcd" s2 := "abcd" validate.VarWithValue(s1, s2, "eqcsfield") // returns true

WARNING: a struct can be passed for validation eg. time.Time is a struct or if you have a custom type and have registered a custom type handler, so must allow it; however unforeseen validations will occur if trying to validate a struct that is meant to be passed to 'validate.Struct'

It returns InvalidValidationError for bad values passed in and nil or ValidationErrors as error otherwise. You will need to assert the error if it's not nil eg. err.(validator.ValidationErrors) to access the array of errors. validate Array, Slice and maps fields which may contain more than one error

type ValidationErrors Uses

type ValidationErrors []FieldError

ValidationErrors is an array of FieldError's for use in custom error messages post validation.

func (ValidationErrors) Error Uses

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 array

func (ValidationErrors) Translate Uses

func (ve ValidationErrors) Translate(ut ut.Translator) ValidationErrorsTranslations

Translate translates all of the ValidationErrors

type ValidationErrorsTranslations Uses

type ValidationErrorsTranslations map[string]string

ValidationErrorsTranslations is the translation return type

Directories

PathSynopsis
translations/en
translations/fr
translations/id
translations/nl
translations/zh

Package validator imports 17 packages (graph) and is imported by 193 packages. Updated 2018-11-05. Refresh now. Tools for package owners.