Laravel 5.4 API/Request Validate Boolean

For some API work in Laravel, I wanted to validate that the incoming request parameter was a boolean value. At first I tried using the built in boolean slug validator but it didn’t accept all of the ‘boolean’ values I wanted to use. (Also there were weird scenarios where string values of false were triggering as true - like what I wrote about here.

In Laravel 5.4 (I mention this version because Laravel has recently updated so this validator format may not be the best anymore), I made the following validator:

<?php
/**
 * Validator to test for any boolean value, not just ones that is_bool() tests for.
 */
declare(strict_types=1);

namespace App\Validators;

use Illuminate\Contracts\Validation\Validator;

/**
 * Class AnyBooleanValueValidator
 * @package App\Validators
 */
class AnyBooleanValueValidator
{
  /**
   * This is invoked by the validator rule 'any_boolean_value'
   * 
   * @param $attribute string the attribute name that is validating
   * @param $value mixed the value that we're testing
   * @param $parameters array 
   * @param $validator Validator The Validator instance
   * @return bool
   */
  public function validate($attribute, $value, $parameters = [], Validator $validator = null) {
    return in_array($value, [
      '1', 1, "true", true, 'yes', 'on', 
      '0', 0, "false", false, 'no', 'off', ''
    ], true);
  }
}

Then, I registered any_boolean_value in the AppServiceProvider using the following line:

Validator::extend('any_boolean_value', AnyBooleanValueValidator::class);

Finally, I added an error translation in the validation language resource file.

'any_boolean_value' => 'The :attribute field must be a boolean type value. (Try true or false, 1 or 0).',

Now I can use that slug for validation on boolean values to allow in “acceptable” boolean values.