Generate random passwords.

random-password.php

<?php

/**
 * Generate random password
 *
 * @see <https://gist.github.com/jrobinsonc/ef4245a6e915a038f108e12980ac24bc>
 * @param  int    $len   Number of characters the password should have.
 * @param  string $types Types of characters the password should have.
*                        Options are: l for lowercase, u for uppercase, d for digital, s for special.
 * @return string
 */
function randomPassword($len, $types = 'luds')
{
    $charsTypes = [
        'l' => 'abcdefghijklmnopqrstuvwxyz',
        'u' => 'ABCDEFGHIJKLMNOPQRSTUVWXYZ',
        'd' => '1234567890',
        's' => '@#$%&()_+!~\/:;-*?',
    ];
    $password = '';
    $typesArr = str_split($types);

    while (strlen($password) < $len) {
        $type = current($typesArr);

        $charsList = $charsTypes[$type];
        $randomCharNum = mt_rand(0, strlen($charsList) - 1);
        $password .= $charsList[$randomCharNum];

        if (! next($typesArr)) {
            reset($typesArr);
        }
    }
    
    return str_shuffle($password);
}