validator
This is a modified version based off github.com/go-playground/validator/v10 to have better i18n support for the binding middleware.
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.
Installation
The minimum requirement of Go is 1.16.
go get github.com/flamego/validator
Error return value
Validation functions 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
- Simple
- Custom Field Types
- Struct Level
- Translations & Custom Errors
- wash - an example application putting it all together
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 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) |
| datetime | Datetime |
| e164 | e164 formatted phone number |
| 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 |
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_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 |
License
This project is under the MIT License. See the LICENSE file for the full license text.
