validator

package module

v10.0.0-...-4980782 Latest Latest Go to latest Published: Dec 5, 2023 License: MIT Imports: 25 Imported by: 0

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Tagged version

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Repository

github.com/integration-system/validator

Links

Open Source Insights

README ¶

Package validator

License

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.
Ability to dive into both map keys and values for validation
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
Customizable i18n aware error messages.
Default validator for the gin web framework; upgrading from v8 to v9 in gin see here

Installation

Use go get.

go get github.com/go-playground/validator/v10

Then import the validator package into your own code.

import "github.com/integration-system/validator/v10"

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

Usage and documentation

Please see https://pkg.go.dev/github.com/go-playground/validator/v10 for detailed usage docs.

Examples:

Baked-in Validations

Special Notes:

If new to using validator it is highly recommended to initialize it using the WithRequiredStructEnabled option which is opt-in to new behaviour that will become the default behaviour in v11+. See documentation for more details.

validate := validator.New(validator.WithRequiredStructEnabled())

Fields:

Tag	Description
eqcsfield	Field Equals Another Field (relative)
eqfield	Field Equals Another Field
fieldcontains	Check the indicated characters are present in the Field
fieldexcludes	Check the indicated characters are not present in the field
gtcsfield	Field Greater Than Another Relative Field
gtecsfield	Field Greater Than or Equal To Another Relative Field
gtefield	Field Greater Than or Equal To Another Field
gtfield	Field Greater Than Another Field
ltcsfield	Less Than Another Relative Field
ltecsfield	Less Than or Equal To Another Relative Field
ltefield	Less Than or Equal To Another Field
ltfield	Less Than Another Field
necsfield	Field Does Not Equal Another Field (relative)
nefield	Field Does Not Equal Another Field

Network:

Tag	Description
cidr	Classless Inter-Domain Routing CIDR
cidrv4	Classless Inter-Domain Routing CIDRv4
cidrv6	Classless Inter-Domain Routing CIDRv6
datauri	Data URL
fqdn	Full Qualified Domain Name (FQDN)
hostname	Hostname RFC 952
hostname_port	HostPort
hostname_rfc1123	Hostname RFC 1123
ip	Internet Protocol Address IP
ip4_addr	Internet Protocol Address IPv4
ip6_addr	Internet Protocol Address IPv6
ip_addr	Internet Protocol Address IP
ipv4	Internet Protocol Address IPv4
ipv6	Internet Protocol Address IPv6
mac	Media Access Control Address MAC
tcp4_addr	Transmission Control Protocol Address TCPv4
tcp6_addr	Transmission Control Protocol Address TCPv6
tcp_addr	Transmission Control Protocol Address TCP
udp4_addr	User Datagram Protocol Address UDPv4
udp6_addr	User Datagram Protocol Address UDPv6
udp_addr	User Datagram Protocol Address UDP
unix_addr	Unix domain socket end point Address
uri	URI String
url	URL String
http_url	HTTP URL String
url_encoded	URL Encoded
urn_rfc2141	Urn RFC 2141 String

Strings:

Tag	Description
alpha	Alpha Only
alphanum	Alphanumeric
alphanumunicode	Alphanumeric Unicode
alphaunicode	Alpha Unicode
ascii	ASCII
boolean	Boolean
contains	Contains
containsany	Contains Any
containsrune	Contains Rune
endsnotwith	Ends Not With
endswith	Ends With
excludes	Excludes
excludesall	Excludes All
excludesrune	Excludes Rune
lowercase	Lowercase
multibyte	Multi-Byte Characters
number	Number
numeric	Numeric
printascii	Printable ASCII
startsnotwith	Starts Not With
startswith	Starts With
uppercase	Uppercase

Format:

Tag	Description
base64	Base64 String
base64url	Base64URL String
base64rawurl	Base64RawURL String
bic	Business Identifier Code (ISO 9362)
bcp47_language_tag	Language tag (BCP 47)
btc_addr	Bitcoin Address
btc_addr_bech32	Bitcoin Bech32 Address (segwit)
credit_card	Credit Card Number
mongodb	MongoDB ObjectID
cron	Cron
spicedb	SpiceDb ObjectID/Permission/Type
datetime	Datetime
e164	e164 formatted phone number
email	E-mail String
eth_addr	Ethereum Address
hexadecimal	Hexadecimal String
hexcolor	Hexcolor String
hsl	HSL String
hsla	HSLA String
html	HTML Tags
html_encoded	HTML Encoded
isbn	International Standard Book Number
isbn10	International Standard Book Number 10
isbn13	International Standard Book Number 13
issn	International Standard Serial Number
iso3166_1_alpha2	Two-letter country code (ISO 3166-1 alpha-2)
iso3166_1_alpha3	Three-letter country code (ISO 3166-1 alpha-3)
iso3166_1_alpha_numeric	Numeric country code (ISO 3166-1 numeric)
iso3166_2	Country subdivision code (ISO 3166-2)
iso4217	Currency code (ISO 4217)
json	JSON
jwt	JSON Web Token (JWT)
latitude	Latitude
longitude	Longitude
luhn_checksum	Luhn Algorithm Checksum (for strings and (u)int)
postcode_iso3166_alpha2	Postcode
postcode_iso3166_alpha2_field	Postcode
rgb	RGB String
rgba	RGBA String
ssn	Social Security Number SSN
timezone	Timezone
uuid	Universally Unique Identifier UUID
uuid3	Universally Unique Identifier UUID v3
uuid3_rfc4122	Universally Unique Identifier UUID v3 RFC4122
uuid4	Universally Unique Identifier UUID v4
uuid4_rfc4122	Universally Unique Identifier UUID v4 RFC4122
uuid5	Universally Unique Identifier UUID v5
uuid5_rfc4122	Universally Unique Identifier UUID v5 RFC4122
uuid_rfc4122	Universally Unique Identifier UUID RFC4122
md4	MD4 hash
md5	MD5 hash
sha256	SHA256 hash
sha384	SHA384 hash
sha512	SHA512 hash
ripemd128	RIPEMD-128 hash
ripemd128	RIPEMD-160 hash
tiger128	TIGER128 hash
tiger160	TIGER160 hash
tiger192	TIGER192 hash
semver	Semantic Versioning 2.0.0
ulid	Universally Unique Lexicographically Sortable Identifier ULID
cve	Common Vulnerabilities and Exposures Identifier (CVE id)

Comparisons:

Tag	Description
eq	Equals
eq_ignore_case	Equals ignoring case
gt	Greater than
gte	Greater than or equal
lt	Less Than
lte	Less Than or Equal
ne	Not Equal
ne_ignore_case	Not Equal ignoring case

Other:

Tag	Description
dir	Existing Directory
dirpath	Directory Path
file	Existing File
filepath	File Path
image	Image
isdefault	Is Default
len	Length
max	Maximum
min	Minimum
oneof	One Of
required	Required
required_if	Required If
required_unless	Required Unless
required_with	Required With
required_with_all	Required With All
required_without	Required Without
required_without_all	Required Without All
excluded_if	Excluded If
excluded_unless	Excluded Unless
excluded_with	Excluded With
excluded_with_all	Excluded With All
excluded_without	Excluded Without
excluded_without_all	Excluded Without All
unique	Unique

Aliases:

Tag	Description
iscolor	hexcolor\|rgb\|rgba\|hsl\|hsla
country_code	iso3166_1_alpha2\|iso3166_1_alpha3\|iso3166_1_alpha_numeric

Benchmarks

Run on MacBook Pro (15-inch, 2017) go version go1.10.2 darwin/amd64

go version go1.21.0 darwin/arm64
goos: darwin
goarch: arm64
pkg: github.com/go-playground/validator/v10
BenchmarkFieldSuccess-8                                         33142266                35.94 ns/op            0 B/op          0 allocs/op
BenchmarkFieldSuccessParallel-8                                 200816191                6.568 ns/op           0 B/op          0 allocs/op
BenchmarkFieldFailure-8                                          6779707               175.1 ns/op           200 B/op          4 allocs/op
BenchmarkFieldFailureParallel-8                                 11044147               108.4 ns/op           200 B/op          4 allocs/op
BenchmarkFieldArrayDiveSuccess-8                                 6054232               194.4 ns/op            97 B/op          5 allocs/op
BenchmarkFieldArrayDiveSuccessParallel-8                        12523388                94.07 ns/op           97 B/op          5 allocs/op
BenchmarkFieldArrayDiveFailure-8                                 3587043               334.3 ns/op           300 B/op         10 allocs/op
BenchmarkFieldArrayDiveFailureParallel-8                         5816665               200.8 ns/op           300 B/op         10 allocs/op
BenchmarkFieldMapDiveSuccess-8                                   2217910               540.1 ns/op           288 B/op         14 allocs/op
BenchmarkFieldMapDiveSuccessParallel-8                           4446698               258.7 ns/op           288 B/op         14 allocs/op
BenchmarkFieldMapDiveFailure-8                                   2392759               504.6 ns/op           376 B/op         13 allocs/op
BenchmarkFieldMapDiveFailureParallel-8                           4244199               286.9 ns/op           376 B/op         13 allocs/op
BenchmarkFieldMapDiveWithKeysSuccess-8                           2005857               592.1 ns/op           288 B/op         14 allocs/op
BenchmarkFieldMapDiveWithKeysSuccessParallel-8                   4400850               296.9 ns/op           288 B/op         14 allocs/op
BenchmarkFieldMapDiveWithKeysFailure-8                           1850227               643.8 ns/op           553 B/op         16 allocs/op
BenchmarkFieldMapDiveWithKeysFailureParallel-8                   3293233               375.1 ns/op           553 B/op         16 allocs/op
BenchmarkFieldCustomTypeSuccess-8                               12174412                98.25 ns/op           32 B/op          2 allocs/op
BenchmarkFieldCustomTypeSuccessParallel-8                       34389907                35.49 ns/op           32 B/op          2 allocs/op
BenchmarkFieldCustomTypeFailure-8                                7582524               156.6 ns/op           184 B/op          3 allocs/op
BenchmarkFieldCustomTypeFailureParallel-8                       13019902                92.79 ns/op          184 B/op          3 allocs/op
BenchmarkFieldOrTagSuccess-8                                     3427260               349.4 ns/op            16 B/op          1 allocs/op
BenchmarkFieldOrTagSuccessParallel-8                            15144128                81.25 ns/op           16 B/op          1 allocs/op
BenchmarkFieldOrTagFailure-8                                     5913546               201.9 ns/op           216 B/op          5 allocs/op
BenchmarkFieldOrTagFailureParallel-8                             9810212               113.7 ns/op           216 B/op          5 allocs/op
BenchmarkStructLevelValidationSuccess-8                         13456327                87.66 ns/op           16 B/op          1 allocs/op
BenchmarkStructLevelValidationSuccessParallel-8                 41818888                27.77 ns/op           16 B/op          1 allocs/op
BenchmarkStructLevelValidationFailure-8                          4166284               272.6 ns/op           264 B/op          7 allocs/op
BenchmarkStructLevelValidationFailureParallel-8                  7594581               152.1 ns/op           264 B/op          7 allocs/op
BenchmarkStructSimpleCustomTypeSuccess-8                         6508082               182.6 ns/op            32 B/op          2 allocs/op
BenchmarkStructSimpleCustomTypeSuccessParallel-8                23078605                54.78 ns/op           32 B/op          2 allocs/op
BenchmarkStructSimpleCustomTypeFailure-8                         3118352               381.0 ns/op           416 B/op          9 allocs/op
BenchmarkStructSimpleCustomTypeFailureParallel-8                 5300738               224.1 ns/op           432 B/op         10 allocs/op
BenchmarkStructFilteredSuccess-8                                 4761807               251.1 ns/op           216 B/op          5 allocs/op
BenchmarkStructFilteredSuccessParallel-8                         8792598               128.6 ns/op           216 B/op          5 allocs/op
BenchmarkStructFilteredFailure-8                                 5202573               232.1 ns/op           216 B/op          5 allocs/op
BenchmarkStructFilteredFailureParallel-8                         9591267               121.4 ns/op           216 B/op          5 allocs/op
BenchmarkStructPartialSuccess-8                                  5188512               231.6 ns/op           224 B/op          4 allocs/op
BenchmarkStructPartialSuccessParallel-8                          9179776               123.1 ns/op           224 B/op          4 allocs/op
BenchmarkStructPartialFailure-8                                  3071212               392.5 ns/op           440 B/op          9 allocs/op
BenchmarkStructPartialFailureParallel-8                          5344261               223.7 ns/op           440 B/op          9 allocs/op
BenchmarkStructExceptSuccess-8                                   3184230               375.0 ns/op           424 B/op          8 allocs/op
BenchmarkStructExceptSuccessParallel-8                          10090130               108.9 ns/op           208 B/op          3 allocs/op
BenchmarkStructExceptFailure-8                                   3347226               357.7 ns/op           424 B/op          8 allocs/op
BenchmarkStructExceptFailureParallel-8                           5654923               209.5 ns/op           424 B/op          8 allocs/op
BenchmarkStructSimpleCrossFieldSuccess-8                         5232265               229.1 ns/op            56 B/op          3 allocs/op
BenchmarkStructSimpleCrossFieldSuccessParallel-8                17436674                64.75 ns/op           56 B/op          3 allocs/op
BenchmarkStructSimpleCrossFieldFailure-8                         3128613               383.6 ns/op           272 B/op          8 allocs/op
BenchmarkStructSimpleCrossFieldFailureParallel-8                 6994113               168.8 ns/op           272 B/op          8 allocs/op
BenchmarkStructSimpleCrossStructCrossFieldSuccess-8              3506487               340.9 ns/op            64 B/op          4 allocs/op
BenchmarkStructSimpleCrossStructCrossFieldSuccessParallel-8     13431300                91.77 ns/op           64 B/op          4 allocs/op
BenchmarkStructSimpleCrossStructCrossFieldFailure-8              2410566               500.9 ns/op           288 B/op          9 allocs/op
BenchmarkStructSimpleCrossStructCrossFieldFailureParallel-8      6344510               188.2 ns/op           288 B/op          9 allocs/op
BenchmarkStructSimpleSuccess-8                                   8922726               133.8 ns/op             0 B/op          0 allocs/op
BenchmarkStructSimpleSuccessParallel-8                          55291153                23.63 ns/op            0 B/op          0 allocs/op
BenchmarkStructSimpleFailure-8                                   3171553               378.4 ns/op           416 B/op          9 allocs/op
BenchmarkStructSimpleFailureParallel-8                           5571692               212.0 ns/op           416 B/op          9 allocs/op
BenchmarkStructComplexSuccess-8                                  1683750               714.5 ns/op           224 B/op          5 allocs/op
BenchmarkStructComplexSuccessParallel-8                          4578046               257.0 ns/op           224 B/op          5 allocs/op
BenchmarkStructComplexFailure-8                                   481585              2547 ns/op            3041 B/op         48 allocs/op
BenchmarkStructComplexFailureParallel-8                           965764              1577 ns/op            3040 B/op         48 allocs/op
BenchmarkOneof-8                                                17380881                68.50 ns/op            0 B/op          0 allocs/op
BenchmarkOneofParallel-8                                         8084733               153.5 ns/op             0 B/op          0 allocs/op

Complementary Software

Here is a list of software that complements 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.
mold - A general library to help modify or set data within data structures and other objects

How to Contribute

Make a pull request...

License

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

Maintainers

This project has grown large enough that more than one person is required to properly support the community. If you are interested in becoming a maintainer please reach out to me https://github.com/deankarn

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.

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

Singleton ¶

Validator is designed to be thread-safe and used as a singleton instance. It caches information about your struct and validations, in essence only parsing your validation tags once per struct type. Using multiple instances neglects the benefit of caching. The not thread-safe functions are explicitly marked as such in the documentation.

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 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: rgb|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 your 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

Omit Nil ¶

Allows to skip the validation if the value is nil (same as omitempty, but only for the nil-values).

Usage: omitnil

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,eq=1|eq=2,endkeys,required"
// gt=0 will be applied to the map itself
// eq=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
// eq=1|eq=2 will be applied to each array element in 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. For structs ensures value is not the zero value when using WithRequiredStructEnabled.

Usage: required

Required If ¶

The field under validation must be present and not empty only if all the other specified fields are equal to the value following the specified field. For strings ensures value is not "". For slices, maps, pointers, interfaces, channels and functions ensures the value is not nil. For structs ensures value is not the zero value.

Usage: required_if

Examples:

// require the field if the Field1 is equal to the parameter given:
Usage: required_if=Field1 foobar

// require the field if the Field1 and Field2 is equal to the value respectively:
Usage: required_if=Field1 foo Field2 bar

Required Unless ¶

The field under validation must be present and not empty unless all the other specified fields are equal to the value following the specified field. For strings ensures value is not "". For slices, maps, pointers, interfaces, channels and functions ensures the value is not nil. For structs ensures value is not the zero value.

Usage: required_unless

Examples:

// require the field unless the Field1 is equal to the parameter given:
Usage: required_unless=Field1 foobar

// require the field unless the Field1 and Field2 is equal to the value respectively:
Usage: required_unless=Field1 foo Field2 bar

Required With ¶

The field under validation must be present and not empty only if any of the other specified fields are present. For strings ensures value is not "". For slices, maps, pointers, interfaces, channels and functions ensures the value is not nil. For structs ensures value is not the zero value.

Usage: required_with

Examples:

// require the field if the Field1 is present:
Usage: required_with=Field1

// require the field if the Field1 or Field2 is present:
Usage: required_with=Field1 Field2

Required With All ¶

The field under validation must be present and not empty only if all of the other specified fields are present. For strings ensures value is not "". For slices, maps, pointers, interfaces, channels and functions ensures the value is not nil. For structs ensures value is not the zero value.

Usage: required_with_all

Example:

// require the field if the Field1 and Field2 is present:
Usage: required_with_all=Field1 Field2

Required Without ¶

The field under validation must be present and not empty only when any of the other specified fields are not present. For strings ensures value is not "". For slices, maps, pointers, interfaces, channels and functions ensures the value is not nil. For structs ensures value is not the zero value.

Usage: required_without

Examples:

// require the field if the Field1 is not present:
Usage: required_without=Field1

// require the field if the Field1 or Field2 is not present:
Usage: required_without=Field1 Field2

Required Without All ¶

The field under validation must be present and not empty only when all of the other specified fields are not present. For strings ensures value is not "". For slices, maps, pointers, interfaces, channels and functions ensures the value is not nil. For structs ensures value is not the zero value.

Usage: required_without_all

Example:

// require the field if the Field1 and Field2 is not present:
Usage: required_without_all=Field1 Field2

Excluded If ¶

The field under validation must not be present or not empty only if all the other specified fields are equal to the value following the specified field. For strings ensures value is not "". For slices, maps, pointers, interfaces, channels and functions ensures the value is not nil. For structs ensures value is not the zero value.

Usage: excluded_if

Examples:

// exclude the field if the Field1 is equal to the parameter given:
Usage: excluded_if=Field1 foobar

// exclude the field if the Field1 and Field2 is equal to the value respectively:
Usage: excluded_if=Field1 foo Field2 bar

Excluded Unless ¶

The field under validation must not be present or empty unless all the other specified fields are equal to the value following the specified field. For strings ensures value is not "". For slices, maps, pointers, interfaces, channels and functions ensures the value is not nil. For structs ensures value is not the zero value.

Usage: excluded_unless

Examples:

// exclude the field unless the Field1 is equal to the parameter given:
Usage: excluded_unless=Field1 foobar

// exclude the field unless the Field1 and Field2 is equal to the value respectively:
Usage: excluded_unless=Field1 foo Field2 bar

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.

Example #1

Usage: len=10

Example #2 (time.Duration)

For time.Duration, len will ensure that the value is equal to the duration given in the parameter.

Usage: len=1h30m

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.

Example #1

Usage: max=10

Example #2 (time.Duration)

For time.Duration, max will ensure that the value is less than or equal to the duration given in the parameter.

Usage: max=1h30m

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.

Example #1

Usage: min=10

Example #2 (time.Duration)

For time.Duration, min will ensure that the value is greater than or equal to the duration given in the parameter.

Usage: min=1h30m

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.

Example #1

Usage: eq=10

Example #2 (time.Duration)

For time.Duration, eq will ensure that the value is equal to the duration given in the parameter.

Usage: eq=1h30m

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.

Example #1

Usage: ne=10

Example #2 (time.Duration)

For time.Duration, ne will ensure that the value is not equal to the duration given in the parameter.

Usage: ne=1h30m

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. To match strings with spaces in them, include the target string between single quotes.

Usage: oneof=red green
       oneof='red green' 'blue yellow'
       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

Example #3 (time.Duration)

For time.Duration, gt will ensure that the value is greater than the duration given in the parameter.

Usage: gt=1h30m

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

Example #3 (time.Duration)

For time.Duration, gte will ensure that the value is greater than or equal to the duration given in the parameter.

Usage: gte=1h30m

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

Example #3 (time.Duration)

For time.Duration, lt will ensure that the value is less than the duration given in the parameter.

Usage: lt=1h30m

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

Example #3 (time.Duration)

For time.Duration, lte will ensure that the value is less than or equal to the duration given in the parameter.

Usage: lte=1h30m

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, time.Duration 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, time.Duration 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, time.Duration 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, time.Duration 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

Field Contains Another Field ¶

This does the same as contains except for struct fields. It should only be used with string types. See the behavior of reflect.Value.String() for behavior on other types.

Usage: containsfield=InnerStructField.Field

Field Excludes Another Field ¶

This does the same as excludes except for struct fields. It should only be used with string types. See the behavior of reflect.Value.String() for behavior on other types.

Usage: excludesfield=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. For slices of struct, unique will ensure that there are no duplicate values in a field of the struct specified via a parameter.

// For arrays, slices, and maps:
Usage: unique

// For slices of struct:
Usage: unique=field

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

Boolean ¶

This validates that a string value can successfully be parsed into a boolean with strconv.ParseBool

Usage: boolean

Number ¶

This validates that a string value contains number values only. For integers or float it returns true.

Usage: number

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

Lowercase String ¶

This validates that a string value contains only lowercase characters. An empty string is not a valid lowercase string.

Usage: lowercase

Uppercase String ¶

This validates that a string value contains only uppercase characters. An empty string is not a valid uppercase string.

Usage: uppercase

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.164 Phone Number String ¶

This validates that a string value contains a valid E.164 Phone number https://en.wikipedia.org/wiki/E.164 (ex. +1123456789)

Usage: e164

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 possibilities.

Usage: email

JSON String ¶

This validates that a string value is valid JSON

Usage: json

JWT String ¶

This validates that a string value is a valid JWT

Usage: jwt

File ¶

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

Image path ¶

This validates that a string value contains a valid file path and that the file exists on the machine and is an image. This is done using os.Stat and github.com/gabriel-vasile/mimetype

Usage: image

File Path ¶

This validates that a string value contains a valid file path but does not validate the existence of that file. This is done using os.Stat, which is a platform independent function.

Usage: filepath

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

Urn RFC 2141 String RFC 2141 String">¶

This validataes that a string value contains a valid URN according to the RFC 2141 spec.

Usage: urn_rfc2141

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 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

Base64RawURL String ¶

This validates that a string value contains a valid base64 URL safe value, but without = padding, according the RFC4648 spec, section 3.2. 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.

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=@

Starts With ¶

This validates that a string value starts with the supplied string value

Usage: startswith=hello

Ends With ¶

This validates that a string value ends with the supplied string value

Usage: endswith=goodbye

Does Not Start With ¶

This validates that a string value does not start with the supplied string value

Usage: startsnotwith=hello

Does Not End With ¶

This validates that a string value does not end with the supplied string value

Usage: endsnotwith=goodbye

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. Uppercase UUID values will not pass - use `uuid_rfc4122` instead.

Usage: uuid

Universally Unique Identifier UUID v3 ¶

This validates that a string value contains a valid version 3 UUID. Uppercase UUID values will not pass - use `uuid3_rfc4122` instead.

Usage: uuid3

Universally Unique Identifier UUID v4 ¶

This validates that a string value contains a valid version 4 UUID. Uppercase UUID values will not pass - use `uuid4_rfc4122` instead.

Usage: uuid4

Universally Unique Identifier UUID v5 ¶

This validates that a string value contains a valid version 5 UUID. Uppercase UUID values will not pass - use `uuid5_rfc4122` instead.

Usage: uuid5

Universally Unique Lexicographically Sortable Identifier ULID ¶

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

Usage: ulid

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 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 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

Directory ¶

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

Usage: dir

Directory Path ¶

This validates that a string value contains a valid directory but does not validate the existence of that directory. This is done using os.Stat, which is a platform independent function. It is safest to suffix the string with os.PathSeparator if the directory may not exist at the time of validation.

Usage: dirpath

HostPort ¶

This validates that a string value contains a valid DNS hostname and port that can be used to valiate fields typically passed to sockets and connections.

Usage: hostname_port

Datetime ¶

This validates that a string value is a valid datetime based on the supplied datetime format. Supplied format must match the official Go time format layout as documented in https://golang.org/pkg/time/

Usage: datetime=2006-01-02

Iso3166-1 alpha-2 ¶

This validates that a string value is a valid country code based on iso3166-1 alpha-2 standard. see: https://www.iso.org/iso-3166-country-codes.html

Usage: iso3166_1_alpha2

Iso3166-1 alpha-3 ¶

This validates that a string value is a valid country code based on iso3166-1 alpha-3 standard. see: https://www.iso.org/iso-3166-country-codes.html

Usage: iso3166_1_alpha3

Iso3166-1 alpha-numeric ¶

This validates that a string value is a valid country code based on iso3166-1 alpha-numeric standard. see: https://www.iso.org/iso-3166-country-codes.html

Usage: iso3166_1_alpha3

BCP 47 Language Tag ¶

This validates that a string value is a valid BCP 47 language tag, as parsed by language.Parse. More information on https://pkg.go.dev/golang.org/x/text/language

Usage: bcp47_language_tag

BIC (SWIFT code)

This validates that a string value is a valid Business Identifier Code (SWIFT code), defined in ISO 9362. More information on https://www.iso.org/standard/60390.html

Usage: bic

RFC 1035 label RFC 1035 label">¶

This validates that a string value is a valid dns RFC 1035 label, defined in RFC 1035. More information on https://datatracker.ietf.org/doc/html/rfc1035

Usage: dns_rfc1035_label

TimeZone ¶

This validates that a string value is a valid time zone based on the time zone database present on the system. Although empty value and Local value are allowed by time.LoadLocation golang function, they are not allowed by this validator. More information on https://golang.org/pkg/time/#LoadLocation

Usage: timezone

Semantic Version ¶

This validates that a string value is a valid semver version, defined in Semantic Versioning 2.0.0. More information on https://semver.org/

Usage: semver

CVE Identifier ¶

This validates that a string value is a valid cve id, defined in cve mitre. More information on https://cve.mitre.org/

Usage: cve

Credit Card ¶

This validates that a string value contains a valid credit card number using Luhn algorithm.

Usage: credit_card

Luhn Checksum ¶

Usage: luhn_checksum

This validates that a string or (u)int value contains a valid checksum using the Luhn algorithm.

MongoDb ObjectID ¶

This validates that a string is a valid 24 character hexadecimal string.

Usage: mongodb

Cron ¶

This validates that a string value contains a valid cron expression.

Usage: cron

SpiceDb ObjectID/Permission/Object Type ¶

This validates that a string is valid for use with SpiceDb for the indicated purpose. If no purpose is given, a purpose of 'id' is assumed.

Usage: spicedb=id|permission|type

Alias Validators and Tags ¶

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)
"country_code"
	alias is "iso3166_1_alpha2|iso3166_1_alpha3|iso3166_1_alpha_numeric" (Usage: country_code)

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!

Non standard validators ¶

A collection of validation rules that are frequently needed but are more complex than the ones found in the baked in validators. A non standard validator must be registered manually like you would with your own custom validation functions.

Example of registration and use:

type Test struct {
	TestField string `validate:"yourtag"`
}

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

validate := validator.New()
validate.RegisterValidation("yourtag", validators.NotBlank)

Here is a list of the current non standard validators:

NotBlank
	This validates that the value is not blank or with length zero.
	For strings ensures they do not contain only spaces. For channels, maps, slices and arrays
	ensures they don't have zero length. For others, a non empty value is required.

	Usage: notblank

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 ¶

type CustomTypeFunc
type FieldError
type FieldLevel
type FilterFunc
type Func
type FuncCtx
type InvalidValidationError
- func (e *InvalidValidationError) Error() string
type Option
- func WithRequiredStructEnabled() Option
type RegisterTranslationsFunc
type StructLevel
type StructLevelFunc
type StructLevelFuncCtx
type TagNameFunc
type TranslationFunc
type Validate
- func New(options ...Option) *Validate
- func (v *Validate) RegisterAlias(alias, tags string)
- func (v *Validate) RegisterCustomTypeFunc(fn CustomTypeFunc, types ...interface{})
- func (v *Validate) RegisterStructValidation(fn StructLevelFunc, types ...interface{})
- func (v *Validate) RegisterStructValidationCtx(fn StructLevelFuncCtx, types ...interface{})
- func (v *Validate) RegisterStructValidationMapRules(rules map[string]string, types ...interface{})
- func (v *Validate) RegisterTagNameFunc(fn TagNameFunc)
- func (v *Validate) RegisterTranslation(tag string, trans ut.Translator, registerFn RegisterTranslationsFunc, ...) (err error)
- func (v *Validate) RegisterValidation(tag string, fn Func, callValidationEvenIfNull ...bool) error
- func (v *Validate) RegisterValidationCtx(tag string, fn FuncCtx, callValidationEvenIfNull ...bool) error
- func (v *Validate) SetTagName(name string)
- func (v *Validate) Struct(s interface{}) error
- func (v *Validate) StructCtx(ctx context.Context, s interface{}) (err error)
- func (v *Validate) StructExcept(s interface{}, fields ...string) error
- func (v *Validate) StructExceptCtx(ctx context.Context, s interface{}, fields ...string) (err error)
- func (v *Validate) StructFiltered(s interface{}, fn FilterFunc) error
- func (v *Validate) StructFilteredCtx(ctx context.Context, s interface{}, fn FilterFunc) (err error)
- func (v *Validate) StructPartial(s interface{}, fields ...string) error
- func (v *Validate) StructPartialCtx(ctx context.Context, s interface{}, fields ...string) (err error)
- func (v *Validate) ValidateMap(data map[string]interface{}, rules map[string]interface{}) map[string]interface{}
- func (v Validate) ValidateMapCtx(ctx context.Context, data map[string]interface{}, rules map[string]interface{}) map[string]interface{}
- func (v *Validate) Var(field interface{}, tag string) error
- func (v *Validate) VarCtx(ctx context.Context, field interface{}, tag string) (err error)
- func (v *Validate) VarWithValue(field interface{}, other interface{}, tag string) error
- func (v *Validate) VarWithValueCtx(ctx context.Context, field interface{}, other interface{}, tag string) (err error)
type ValidationErrors
- func (ve ValidationErrors) Error() string
- func (ve ValidationErrors) Translate(ut ut.Translator) ValidationErrorsTranslations
type ValidationErrorsTranslations

Constants ¶

This section is empty.

Variables ¶

This section is empty.

Functions ¶

This section is empty.

Types ¶

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 interface {

	// Tag 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

	// ActualTag 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

	// Namespace returns the namespace for the field error, with the tag
	// name taking precedence over the field's 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

	// StructNamespace returns the namespace for the field error, with the field's
	// 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 its name
	StructNamespace() string

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

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

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

	// Param 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

	// Translate returns the FieldError's translated error
	// from the provided 'ut.Translator' and registered 'TranslationFunc'
	//
	// NOTE: if no registered translator can be found it returns the same as
	// calling fe.Error()
	Translate(ut ut.Translator) string

	// Error returns the FieldError's message
	Error() string
}

FieldError contains all functions to get error details

type FieldLevel ¶

type FieldLevel interface {

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

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

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

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

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

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

	// GetTag returns the current validations tag name
	GetTag() 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)

	// GetStructFieldOK 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.
	//
	// Deprecated: Use GetStructFieldOK2() instead which also return if the value is nullable.
	GetStructFieldOK() (reflect.Value, reflect.Kind, bool)

	// GetStructFieldOKAdvanced is the same as GetStructFieldOK except that it accepts the parent struct to start looking for
	// the field and namespace allowing more extensibility for validators.
	//
	// Deprecated: Use GetStructFieldOKAdvanced2() instead which also return if the value is nullable.
	GetStructFieldOKAdvanced(val reflect.Value, namespace string) (reflect.Value, reflect.Kind, bool)

	// GetStructFieldOK2 traverses the parent struct to retrieve a specific field denoted by the provided namespace
	// in the param and returns the field, field kind, if it's a nullable type 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.
	GetStructFieldOK2() (reflect.Value, reflect.Kind, bool, bool)

	// GetStructFieldOKAdvanced2 is the same as GetStructFieldOK except that it accepts the parent struct to start looking for
	// the field and namespace allowing more extensibility for validators.
	GetStructFieldOKAdvanced2(val reflect.Value, namespace string) (reflect.Value, reflect.Kind, bool, bool)
}

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

type FilterFunc ¶

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/skipped from validation

type Func ¶

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 ¶

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 ¶

type InvalidValidationError struct {
	Type reflect.Type
}

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

func (*InvalidValidationError) Error ¶

func (e *InvalidValidationError) Error() string

Error returns InvalidValidationError message

type Option ¶

type Option func(*Validate)

Option represents a configurations option to be applied to validator during initialization.

func WithRequiredStructEnabled ¶

func WithRequiredStructEnabled() Option

WithRequiredStructEnabled enables required tag on non-pointer structs to be applied instead of ignored.

This was made opt-in behaviour in order to maintain backward compatibility with the behaviour previous to being able to apply struct level validations on struct fields directly.

It is recommended you enabled this as it will be the default behaviour in v11+

type RegisterTranslationsFunc ¶

type RegisterTranslationsFunc func(ut ut.Translator) error

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

type StructLevel ¶

type StructLevel interface {

	// Validator returns the main validation object, in case one wants to call validations internally.
	// this is so you don't have to use anonymous functions to get access to the validate
	// instance.
	Validator() *Validate

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

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

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

	// ReportError 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. e.g. 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)

	// ReportValidationErrors reports an error just by passing ValidationErrors
	//
	// NOTES:
	//
	// relativeNamespace and relativeActualNamespace get appended to the
	// existing namespace that validator is on.
	// e.g. 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 current field depth
	ReportValidationErrors(relativeNamespace, relativeActualNamespace string, errs ValidationErrors)
}

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

type StructLevelFunc ¶

type StructLevelFunc func(sl StructLevel)

StructLevelFunc accepts all values needed for struct level validation

type StructLevelFuncCtx ¶

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 via context.Context.

type TagNameFunc ¶

type TagNameFunc func(field reflect.StructField) string

TagNameFunc allows for adding of a custom tag name parser

type TranslationFunc ¶

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

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

type Validate ¶

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

Validate contains the validator settings and cache

func New ¶

func New(options ...Option) *Validate

New returns a new instance of 'validate' with sane defaults. Validate is designed to be thread-safe and used as a singleton instance. It caches information about your struct and validations, in essence only parsing your validation tags once per struct type. Using multiple instances neglects the benefit of caching.

func (*Validate) RegisterAlias ¶

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 ¶

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) RegisterStructValidationCtx ¶

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) RegisterStructValidationMapRules ¶

func (v *Validate) RegisterStructValidationMapRules(rules map[string]string, types ...interface{})

RegisterStructValidationMapRules registers validate map rules. Be aware that map validation rules supersede those defined on a/the struct if present.

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

func (*Validate) RegisterTagNameFunc ¶

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]
    // skip if tag key says it should be ignored
    if name == "-" {
        return ""
    }
    return name
})

func (*Validate) RegisterTranslation ¶

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 ¶

func (v *Validate) RegisterValidation(tag string, fn Func, callValidationEvenIfNull ...bool) 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 ¶

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

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

func (*Validate) SetTagName ¶

func (v *Validate) SetTagName(name string)

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

func (*Validate) Struct ¶

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

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