Package validator
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/go-playground/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
Fields:
Tag | Description |
---|
eqcsfield | Field Equals Another Field (relative) |
eqfield | Field Equals Another Field |
fieldcontains | NOT DOCUMENTED IN doc.go |
fieldexcludes | NOT DOCUMENTED IN doc.go |
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 |
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 | NOT DOCUMENTED IN doc.go |
numeric | Numeric |
printascii | Printable ASCII |
startsnotwith | Starts Not With |
startswith | Starts With |
uppercase | Uppercase |
Format:
Tag | Description |
---|
base64 | Base64 String |
base64url | Base64URL 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 |
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 |
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 |
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 |
Comparisons:
Tag | Description |
---|
eq | Equals |
gt | Greater than |
gte | Greater than or equal |
lt | Less Than |
lte | Less Than or Equal |
ne | Not Equal |
Other:
Tag | Description |
---|
dir | Directory |
file | File path |
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
goos: darwin
goarch: amd64
pkg: github.com/go-playground/validator
BenchmarkFieldSuccess-8 20000000 83.6 ns/op 0 B/op 0 allocs/op
BenchmarkFieldSuccessParallel-8 50000000 26.8 ns/op 0 B/op 0 allocs/op
BenchmarkFieldFailure-8 5000000 291 ns/op 208 B/op 4 allocs/op
BenchmarkFieldFailureParallel-8 20000000 107 ns/op 208 B/op 4 allocs/op
BenchmarkFieldArrayDiveSuccess-8 2000000 623 ns/op 201 B/op 11 allocs/op
BenchmarkFieldArrayDiveSuccessParallel-8 10000000 237 ns/op 201 B/op 11 allocs/op
BenchmarkFieldArrayDiveFailure-8 2000000 859 ns/op 412 B/op 16 allocs/op
BenchmarkFieldArrayDiveFailureParallel-8 5000000 335 ns/op 413 B/op 16 allocs/op
BenchmarkFieldMapDiveSuccess-8 1000000 1292 ns/op 432 B/op 18 allocs/op
BenchmarkFieldMapDiveSuccessParallel-8 3000000 467 ns/op 432 B/op 18 allocs/op
BenchmarkFieldMapDiveFailure-8 1000000 1082 ns/op 512 B/op 16 allocs/op
BenchmarkFieldMapDiveFailureParallel-8 5000000 425 ns/op 512 B/op 16 allocs/op
BenchmarkFieldMapDiveWithKeysSuccess-8 1000000 1539 ns/op 480 B/op 21 allocs/op
BenchmarkFieldMapDiveWithKeysSuccessParallel-8 3000000 613 ns/op 480 B/op 21 allocs/op
BenchmarkFieldMapDiveWithKeysFailure-8 1000000 1413 ns/op 721 B/op 21 allocs/op
BenchmarkFieldMapDiveWithKeysFailureParallel-8 3000000 575 ns/op 721 B/op 21 allocs/op
BenchmarkFieldCustomTypeSuccess-8 10000000 216 ns/op 32 B/op 2 allocs/op
BenchmarkFieldCustomTypeSuccessParallel-8 20000000 82.2 ns/op 32 B/op 2 allocs/op
BenchmarkFieldCustomTypeFailure-8 5000000 274 ns/op 208 B/op 4 allocs/op
BenchmarkFieldCustomTypeFailureParallel-8 20000000 116 ns/op 208 B/op 4 allocs/op
BenchmarkFieldOrTagSuccess-8 2000000 740 ns/op 16 B/op 1 allocs/op
BenchmarkFieldOrTagSuccessParallel-8 3000000 474 ns/op 16 B/op 1 allocs/op
BenchmarkFieldOrTagFailure-8 3000000 471 ns/op 224 B/op 5 allocs/op
BenchmarkFieldOrTagFailureParallel-8 3000000 414 ns/op 224 B/op 5 allocs/op
BenchmarkStructLevelValidationSuccess-8 10000000 213 ns/op 32 B/op 2 allocs/op
BenchmarkStructLevelValidationSuccessParallel-8 20000000 91.8 ns/op 32 B/op 2 allocs/op
BenchmarkStructLevelValidationFailure-8 3000000 473 ns/op 304 B/op 8 allocs/op
BenchmarkStructLevelValidationFailureParallel-8 10000000 234 ns/op 304 B/op 8 allocs/op
BenchmarkStructSimpleCustomTypeSuccess-8 5000000 385 ns/op 32 B/op 2 allocs/op
BenchmarkStructSimpleCustomTypeSuccessParallel-8 10000000 161 ns/op 32 B/op 2 allocs/op
BenchmarkStructSimpleCustomTypeFailure-8 2000000 640 ns/op 424 B/op 9 allocs/op
BenchmarkStructSimpleCustomTypeFailureParallel-8 5000000 318 ns/op 440 B/op 10 allocs/op
BenchmarkStructFilteredSuccess-8 2000000 597 ns/op 288 B/op 9 allocs/op
BenchmarkStructFilteredSuccessParallel-8 10000000 266 ns/op 288 B/op 9 allocs/op
BenchmarkStructFilteredFailure-8 3000000 454 ns/op 256 B/op 7 allocs/op
BenchmarkStructFilteredFailureParallel-8 10000000 214 ns/op 256 B/op 7 allocs/op
BenchmarkStructPartialSuccess-8 3000000 502 ns/op 256 B/op 6 allocs/op
BenchmarkStructPartialSuccessParallel-8 10000000 225 ns/op 256 B/op 6 allocs/op
BenchmarkStructPartialFailure-8 2000000 702 ns/op 480 B/op 11 allocs/op
BenchmarkStructPartialFailureParallel-8 5000000 329 ns/op 480 B/op 11 allocs/op
BenchmarkStructExceptSuccess-8 2000000 793 ns/op 496 B/op 12 allocs/op
BenchmarkStructExceptSuccessParallel-8 10000000 193 ns/op 240 B/op 5 allocs/op
BenchmarkStructExceptFailure-8 2000000 639 ns/op 464 B/op 10 allocs/op
BenchmarkStructExceptFailureParallel-8 5000000 300 ns/op 464 B/op 10 allocs/op
BenchmarkStructSimpleCrossFieldSuccess-8 3000000 417 ns/op 72 B/op 3 allocs/op
BenchmarkStructSimpleCrossFieldSuccessParallel-8 10000000 163 ns/op 72 B/op 3 allocs/op
BenchmarkStructSimpleCrossFieldFailure-8 2000000 645 ns/op 304 B/op 8 allocs/op
BenchmarkStructSimpleCrossFieldFailureParallel-8 5000000 285 ns/op 304 B/op 8 allocs/op
BenchmarkStructSimpleCrossStructCrossFieldSuccess-8 3000000 588 ns/op 80 B/op 4 allocs/op
BenchmarkStructSimpleCrossStructCrossFieldSuccessParallel-8 10000000 221 ns/op 80 B/op 4 allocs/op
BenchmarkStructSimpleCrossStructCrossFieldFailure-8 2000000 868 ns/op 320 B/op 9 allocs/op
BenchmarkStructSimpleCrossStructCrossFieldFailureParallel-8 5000000 337 ns/op 320 B/op 9 allocs/op
BenchmarkStructSimpleSuccess-8 5000000 260 ns/op 0 B/op 0 allocs/op
BenchmarkStructSimpleSuccessParallel-8 20000000 90.6 ns/op 0 B/op 0 allocs/op
BenchmarkStructSimpleFailure-8 2000000 619 ns/op 424 B/op 9 allocs/op
BenchmarkStructSimpleFailureParallel-8 5000000 296 ns/op 424 B/op 9 allocs/op
BenchmarkStructComplexSuccess-8 1000000 1454 ns/op 128 B/op 8 allocs/op
BenchmarkStructComplexSuccessParallel-8 3000000 579 ns/op 128 B/op 8 allocs/op
BenchmarkStructComplexFailure-8 300000 4140 ns/op 3041 B/op 53 allocs/op
BenchmarkStructComplexFailureParallel-8 1000000 2127 ns/op 3041 B/op 53 allocs/op
BenchmarkOneof-8 10000000 140 ns/op 0 B/op 0 allocs/op
BenchmarkOneofParallel-8 20000000 70.1 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