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/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 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
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
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.
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.
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.
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.
Usage: required_without_all
Example:
// require the field if the Field1 and Field2 is not present: Usage: required_without_all=Field1 Field2
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
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
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 possibilities.
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
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 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=@
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
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
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
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!
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
- type RegisterTranslationsFunc
- type StructLevel
- type StructLevelFunc
- type StructLevelFuncCtx
- type TagNameFunc
- type TranslationFunc
- type 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) 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) 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
- type ValidationErrorsTranslations
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type CustomTypeFunc ¶
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 { // 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: if no registered translator 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 ¶
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 // 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) // 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) // 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) // 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. 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 ¶ added in v9.2.0
FilterFunc is the type used to filter fields using StructFiltered(...) function. returning true results in the field being filtered/skiped 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 ¶ added in v9.5.0
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 ¶
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 RegisterTranslationsFunc ¶ added in v9.1.0
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 { // 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 // 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 its 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. 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) // 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 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 ¶ added in v9.5.0
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 ¶ added in v9.1.0
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 (*Validate) RegisterAlias ¶
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 ¶ added in v9.5.0
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 ¶
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 ¶ added in v9.1.0
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 ¶
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 ¶ added in v9.5.0
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 ¶
SetTagName allows for changing of the default tag name of 'validate'
func (*Validate) Struct ¶
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 ¶ added in v9.5.0
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 ¶
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 ¶ added in v9.5.0
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 ¶ added in v9.2.0
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 ¶ added in v9.5.0
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 ¶
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 ¶ added in v9.5.0
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 ¶
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 ¶ added in v9.5.0
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 ¶
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 ¶ added in v9.5.0
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 ¶
type ValidationErrors []FieldError
ValidationErrors is an array of FieldError's for use in custom error messages post validation.
func (ValidationErrors) Error ¶
func (ve ValidationErrors) Error() string
Error is intended for use in development + debugging and not intended to be a production error message. It allows ValidationErrors to subscribe to the Error interface. All information to create an error message specific to your application is contained within the FieldError found within the ValidationErrors array
func (ValidationErrors) Translate ¶ added in v9.1.0
func (ve ValidationErrors) Translate(ut ut.Translator) ValidationErrorsTranslations
Translate translates all of the ValidationErrors
type ValidationErrorsTranslations ¶ added in v9.1.0
ValidationErrorsTranslations is the translation return type