connection php
<?php
function init_db()
{
    try {
        $host = 'localhost';
        $dbname = 'db_name';
        $charset =  'utf8';
        $user =   'root';
        $password =  '';
        $db = new PDO("mysql:host=$host;dbname=$dbname;charset=$charset",
            $user,
            $password);
    } catch (Exception $e) {
        die('Erreur : ' . $e->getMessage());
    }
    return $db;
}
