validator

validator

A simple validation utility for collecting and managing validation errors. Supports boolean and error-based validation with formatted error messages.

Installation

go get github.com/LightArrayCapital/go-utilities/validator

Forked from moonrhythm/validator.

Usage

The validator package provides a Validator type that collects validation errors and allows you to check if all validations passed.

Basic Example

package main

import (
	"fmt"
	"github.com/LightArrayCapital/go-utilities/validator"
)

func validateUser(name string, age int) error {
	v := validator.New()

	// Validate name is not empty
	v.Must(name != "", "name is required")

	// Validate age is positive
	v.Must(age > 0, "age must be positive")

	// Validate age is reasonable
	v.Mustf(age < 150, "age %d is too large", age)

	// Return combined error if any validation failed
	return v.Error()
}

func main() {
	if err := validateUser("", -5); err != nil {
		fmt.Println("Validation failed:", err)
	}
}

Using with Errors

func validateData(data string) error {
	v := validator.New()

	// Check if a function returns an error
	if err := someValidation(data); err != nil {
		v.Must(err, "error during someValidation") // Add the error directly
	}

	// Or use Must with the error directly
	v.Must(anotherValidation(data), "")

	return v.Error()
}

Checking Validation Status

v := validator.New()
v.Must(len(username) >= 3, "username must be at least 3 characters")
v.Must(email != "", "email is required")

if !v.Valid() {
	// Handle validation errors
	return v.Error()
}