rest_api/api/config/database.php

<?php

class DatabaseService {

  protected $glob;

  private $db_host;
  private $db_name;
  private $db_user;
  private $db_password;
  private $connection;

  public function __construct() {
    global $GLOBALS;
    $this->glob =& $GLOBALS;
  }

  public function getConnection() {

    $this->connection = null;
    $this->db_host      = $this->glob['CONF']['DB']['HOST'];
    $this->db_name      = $this->glob['CONF']['DB']['DB_NAME'];
    $this->db_user      = $this->glob['CONF']['DB']['USER'];
    $this->db_password  = $this->glob['CONF']['DB']['PASSWORD'];

    try {
      $this->connection = new PDO("mysql:host=" . $this->db_host . ";dbname=" . $this->db_name, $this->db_user, $this->db_password);
    } catch(PDOException $exception) {
      echo "Connection failed: " . $exception->getMessage();
    }

    return $this->connection;
  }
}
?>