In this article, we are going to learn how to set strong password validation rule in Laravel. Let’s get started:

Table of Contents

1. Make a Rule
2. Apply the Rule
3. Output

Make a Rule

We are going to create a new rule called IsValidPassword. Run this comand:

php artisan make:rule IsValidPassword

Open the new rule IsValidPassword.php file from app/Rules folder and paste this code:

<?php

namespace App\Rules;

use Illuminate\Support\Str;
use Illuminate\Contracts\Validation\Rule;

class IsValidPassword implements Rule
{
    /**
     * Determine if the Length Validation Rule passes.
     *
     * @var boolean
     */
    public $lengthPasses = true;

    /**
     * Determine if the Uppercase Validation Rule passes.
     *
     * @var boolean
     */
    public $uppercasePasses = true;

    /**
     * Determine if the Numeric Validation Rule passes.
     *
     * @var boolean
     */
    public $numericPasses = true;

    /**
     * Determine if the Special Character Validation Rule passes.
     *
     * @var boolean
     */
    public $specialCharacterPasses = true;

    /**
     * Determine if the validation rule passes.
     *
     * @param string $attribute
     * @param mixed $value
     * @return bool
     */
    public function passes($attribute, $value)
    {
        $this->lengthPasses = (Str::length($value) >= 8);
        $this->uppercasePasses = (Str::lower($value) !== $value);
        $this->numericPasses = ((bool)preg_match('/[0-9]/', $value));
        $this->specialCharacterPasses = ((bool)preg_match('/[^A-Za-z0-9]/', $value));

        return ($this->lengthPasses && $this->uppercasePasses && $this->numericPasses && $this->specialCharacterPasses);
    }

    /**
     * Get the validation error message.
     *
     * @return string
     */
    public function message()
    {
        switch (true) {
            case !$this->uppercasePasses
                && $this->numericPasses
                && $this->specialCharacterPasses:
                return 'The :attribute must be at least 8 characters and contain at least 1 uppercase character.';

            case !$this->numericPasses
                && $this->uppercasePasses
                && $this->specialCharacterPasses:
                return 'The :attribute must be at least 8 characters and contain at least 1 number.';

            case !$this->specialCharacterPasses
                && $this->uppercasePasses
                && $this->numericPasses:
                return 'The :attribute must be at least 8 characters and contain at least 1 special character.';

            case !$this->uppercasePasses
                && !$this->numericPasses
                && $this->specialCharacterPasses:
                return 'The :attribute must be at least 8 characters and contain at least 1 uppercase character and 1 number.';

            case !$this->uppercasePasses
                && !$this->specialCharacterPasses
                && $this->numericPasses:
                return 'The :attribute must be at least 8 characters and contain at least 1 uppercase character and 1 special character.';

            case !$this->uppercasePasses
                && !$this->numericPasses
                && !$this->specialCharacterPasses:
                return 'The :attribute must be at least 8 characters and contain at least 1 uppercase character, 1 number, and 1 special character.';

            default:
                return 'The :attribute must be at least 8 characters.';
        }
    }
}

Apply the Rule

Now we can apply the rule in any password field. Let’s apply in RegisterController. Open the controller from app/Http/Controller/Auth folder and apply the rule like:

use App\Rules\IsValidPassword;

protected function validator(array $data)
{
    return Validator::make($data, [
        'name' => ['required', 'string', 'max:255'],
        'email' => ['required', 'string', 'email', 'max:255', 'unique:users'],
        'password' => ['required', 'string', 'confirmed', new isValidPassword()],
    ]);
}

Output

Run the application and test registration form. You’ll notice validation error like this: