Snippet: Cookie class for PHP

16 Oct 2008

Today’s snippet is a complete class for normalising cookie usage. In addition to providing methods to set and get cookies you can also check to see if a cookie exists, is empty and delete them without needing to concern yourself with more detail than necessary. Features include…

Cookies Set during a request are immediately available via the Get method.
Deleted cookies immediately cease to exist within the current request.
Pre
defined time spans allow for simple cookie management.
Sensible defaults throughout.

class Cookie
{
  const Session = null;
  const OneDay = 86400;
  const SevenDays = 604800;
  const ThirtyDays = 2592000;
  const SixMonths = 15811200;
  const OneYear = 31536000;
  const Lifetime = -1; // 2030-01-01 00:00:00

  /**
   * Returns true if there is a cookie with this name.
   *
   * @param string $name
   * @return bool
   */
  static public function Exists($name)
  {
    return isset($_COOKIE[$name]);
  }

  /**
   * Returns true if there no cookie with this name or it's empty, or 0,
   * or a few other things. Check http://php.net/empty for a full list.
   *
   * @param string $name
   * @return bool
   */
  static public function IsEmpty($name)
  {
    return empty($_COOKIE[$name]);
  }

  /**
   * Get the value of the given cookie. If the cookie does not exist the value
   * of $default will be returned.
   *
   * @param string $name
   * @param string $default
   * @return mixed
   */
  static public function Get($name, $default = '')
  {
    return (isset($_COOKIE[$name]) ? $_COOKIE[$name] : $default);
  }

  /**
   * Set a cookie. Silently does nothing if headers have already been sent.
   *
   * @param string $name
   * @param string $value
   * @param mixed $expiry
   * @param string $path
   * @param string $domain
   * @return bool
   */
  static public function Set($name, $value, $expiry = self::OneYear, $path = '/', $domain = false)
  {
    $retval = false;
    if (!headers_sent()) {
      if ($domain === false){
        $domain = $_SERVER['HTTP_HOST'];
      }

      if ($expiry === -1) {
        $expiry = 1893456000; // Lifetime = 2030-01-01 00:00:00
      } elseif (is_numeric($expiry)) {
        $expiry += time();
      } else {
        $expiry = strtotime($expiry);
      }

      $retval = @setcookie($name, $value, $expiry, $path, $domain);
      if ($retval) {
        $_COOKIE[$name] = $value;
      }
    }
    return $retval;
  }

  /**
   * Delete a cookie.
   *
   * @param string $name
   * @param string $path
   * @param string $domain
   * @param bool $remove_from_global Set to true to remove this cookie from this request.
   * @return bool
   */
  static public function Delete($name, $path = '/', $domain = false, $remove_from_global = false)
  {
    $retval = false;
    if (!headers_sent()) {
      if ($domain === false) {
        $domain = $_SERVER['HTTP_HOST'];
      }
      $retval = setcookie($name, '', time() - 3600, $path, $domain);

      if ($remove_from_global) {
        unset($_COOKIE[$name]);
      }
    }
    return $retval;
  }
}

Some example usage…

// Style preference, persists only until the browser is closed
Cookie::Set('style', 'black_and_orange', Cookie::Session);

// Remember the users email address to pre-fill the login form when they return
Cookie::Set('rememberme', 'email@domain.com', Cookie::ThirtyDays);

// Tracking cookie that effectively lasts forever
Cookie::Set('tracking', 'sdfoiwuyo8who8wfhow8fhso4', Cookie::Lifetime, '/', '.domain.com');