Multiform Validator Go

Go library made for validating several form fields and common values, such as ASCII, Base64, CEP, CNPJ, CPF, credit card, email, real image bytes, MAC address, MD5, port, postal code, telephone, password, and much more.

This package is the Go version of Multiform Validator. It currently includes ASCII, Base64, CEP, CNPJ, CPF, credit card, email, image, MAC address, MD5, port, postal code, telephone, text, and higher-level validation helpers, with more validators being added over time. The CNPJ validator supports both the old LEGACY numeric CNPJ format and the new alphanumeric CNPJ format, in accordance with the official Receita Federal / SERPRO specification.

Install

go get github.com/Multiform-Validator/go

Usage

package main

import (
	"fmt"
	"os"

	mv "github.com/Multiform-Validator/go"
	"github.com/Multiform-Validator/go/validate"
)

func main() {
	if err := mv.IsAscii("Hello 123!"); err != nil {
		fmt.Println(err)
	}

	if err := mv.IsBase64("SGVsbG8gV29ybGQ="); err != nil {
		fmt.Println(err)
	}

	if err := mv.IsCEP("12345-678"); err != nil {
		fmt.Println(err)
	}

	if err := mv.IsCNPJ("12.ABC.345/01DE-35"); err != nil {
		fmt.Println(err)
	}

	if err := mv.IsCNPJ("04.252.011/0001-10"); err != nil {
		fmt.Println(err)
	}

	if err := mv.IsCPF("123.456.789-09"); err != nil {
		fmt.Println(err)
	}

	fmt.Println(mv.IdentifyFlagCard("4111 1111 1111 1111"))

	if err := mv.IsCreditCard("4111 1111 1111 1111"); err != nil {
		fmt.Println(err)
	}

	fmt.Println(mv.GetOnlyEmail("Contact team: joao@empresa.com, maria@empresa.com"))

	if err := mv.IsEmail("user@example.com"); err != nil {
		fmt.Println(err)
	}

	imageBytes, err := os.ReadFile("avatar.png")
	if err != nil {
		fmt.Println(err)
	}

	if err := mv.IsImage(imageBytes); err != nil {
		fmt.Println(err)
	}

	if err := mv.IsMACAddress("00:1A:2B:3C:4D:5E"); err != nil {
		fmt.Println(err)
	}

	if err := mv.IsPort("8080"); err != nil {
		fmt.Println(err)
	}

	if err := mv.IsPortNumber(8080); err != nil {
		fmt.Println(err)
	}

	if err := mv.IsPostalCode("10045-123", "BR"); err != nil {
		fmt.Println(err)
	}

	if err := mv.IsTelephone("+55 11 91234-5678", "BR"); err != nil {
		fmt.Println(err)
	}

	if err := mv.IsBlank("   "); err != nil {
		fmt.Println(err)
	}

	if err := mv.IsEmpty(""); err != nil {
		fmt.Println(err)
	}

	if err := validate.Email("user@gmail.com", validate.EmailOptions{ValidDomains: true}); err != nil {
		fmt.Println(err)
	}

	if err := validate.Password("MyP@ssw0rd", validate.PasswordOptions{
		MinLength:          8,
		MaxLength:          20,
		RequireUppercase:   true,
		RequireSpecialChar: true,
		RequireNumber:      true,
		RequireLetter:      true,
	}); err != nil {
		fmt.Println(err)
	}
}

You can also import each validator package directly:

import (
	"github.com/Multiform-Validator/go/ascii"
	"github.com/Multiform-Validator/go/base64"
	"github.com/Multiform-Validator/go/cep"
	"github.com/Multiform-Validator/go/cnpj"
	"github.com/Multiform-Validator/go/cpf"
	"github.com/Multiform-Validator/go/creditcard"
	"github.com/Multiform-Validator/go/email"
	"github.com/Multiform-Validator/go/image"
	"github.com/Multiform-Validator/go/macaddress"
	"github.com/Multiform-Validator/go/md5"
	"github.com/Multiform-Validator/go/port"
	"github.com/Multiform-Validator/go/postalcode"
	"github.com/Multiform-Validator/go/telephone"
	"github.com/Multiform-Validator/go/text"
	"github.com/Multiform-Validator/go/validate"
)

Validator Packages

Most validators follow the direct Is* style, such as IsEmail, IsCPF, and IsPort. These are simple checks for one specific value.

The validate package is intentionally separate and works a little differently. It is for higher-level validators with options and composed rules, using the validate.* style, such as validate.Email and validate.Password.

Available Validators

• IsAscii
• IsAsciiBytes
• IsBase64
• IsCEP
• CalculateCNPJCheckDigits
• IsCNPJ
• IsCPF
• IdentifyFlagCard
• IsCreditCard
• GetOnlyEmail
• GetOnlyEmails
• IsEmail
• IsImage
• IsMACAddress
• IsMD5
• IsPort
• IsPortNumber
• IsPostalCode
• IsTelephone
• IsBlank
• IsBlankBytes
• IsEmpty
• IsEmptyBytes
• validate.Email
• validate.Password

IsTelephone accepts an optional country argument. Current country-specific validation supports Brazil, United States, China, Japan, Germany, India, United Kingdom, France, Italy, Canada, and South Korea.

IsPostalCode accepts an optional country argument. Current country-specific validation supports Brazil, United States, Canada, United Kingdom, France, Netherlands, Japan, Spain, South Africa, Germany, Switzerland, and Italy.

IdentifyFlagCard is a special helper from the credit card package, similar to how GetOnlyEmail belongs to the email package. It identifies the card flag by prefix and returns Unknown when no known flag matches.

validate.Email provides higher-level email validation options inspired by the TypeScript package: max length, country suffix, default allowed domains, and custom allowed domains.

validate.Password validates password length and optional uppercase, special character, number, and letter requirements.

Development

make check