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:

• http://stackoverflow.com/a/29138676/3158232
• https://github.com/go-playground/validator/issues/134

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 | | 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 |

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.