How do I set a cookie?

Question

I need to save a cookie for anonymous users in Drupal 8 when users visit the site for the first time, which will be used to display a message.

I can successfully save one using setcookie("FirstTimer", 1, strtotime('+1 year')); but I am sure Drupal 8 should have some alternatives.

I can also use the following code.

$user_is_first_timer = !isset($_COOKIE["Drupal_visitor_FirstTimer"]);

When I open it in Google Chrome, this works, but when I open it in incognito or in Firefox, there is no message. Somehow cached pages are being served.

The code is used in an implementation of hook_page_attachments().

Answer 1

With Drupal 7, Drupal 8, and Drupal 9 you could use user_cookie_save() to store a cookie.

function user_cookie_save(array $values) {
  foreach ($values as $field => $value) {
    // Set cookie for 365 days.
    setrawcookie('Drupal.visitor.' . $field, rawurlencode($value), REQUEST_TIME + 31536000, '/');
  }
}

The first parameter is an array, whose keys are the names of the cookies to set and its values are the cookie values.
user_cookie_save() doesn't allow to set when a cookie expires; cookies created with this function expires after 365 days.

The only method that in Drupal 8 calls user_cookie_save() is SystemController::compactPage().

public function compactPage($mode) {
  user_cookie_save(['admin_compact_mode' => $mode == 'on']);
  return $this->redirect('<front>');
}

Unfortunately, there isn't an equivalent function to read a cookie. In Drupal 8 and Drupal 9, to read the cookie saved from SystemController::compactPage() it's used system_admin_compact_mode().

function system_admin_compact_mode() {
  // PHP converts dots into underscores in cookie names to avoid problems with
  // its parser, so we use a converted cookie name.
  return \Drupal::request()->cookies->get('Drupal_visitor_admin_compact_mode', \Drupal::config('system.site')->get('admin_compact_mode'));
}

In alternative, in Drupal 8 and Drupal 9, you could store cookies using code similar to the one used by BigPipeController::setNoJsCookie() (implemented since Drupal 8.1.x).

if ($request->cookies->has(BigPipeStrategy::NOJS_COOKIE) || !$request->hasSession()) {
  throw new AccessDeniedHttpException();
}
if (!$request->query->has('destination')) {
  throw new HttpException(400, 'The original location is missing.');
}
$response = new LocalRedirectResponse($request->query->get('destination'));

// Set cookie without httpOnly, so that JavaScript can delete it.
$response->headers->setCookie(new Cookie(BigPipeStrategy::NOJS_COOKIE, TRUE, 0, '/', NULL, FALSE, FALSE, FALSE, NULL));
$response->addCacheableDependency((new CacheableMetadata())
  ->addCacheContexts([
    'cookies:' . BigPipeStrategy::NOJS_COOKIE,
    'session.exists',
  ]));
return $response;

This code used the $response object from Symfony, instead of using a PHP function.
It's also more "symmetric," as the same object allows to read and write cookies.

Using $response->headers->setCookie() gives more control over the cookie parameters (the parameters Cookie::__construct() accepts).

Answer 2

Drupal 8 cookies can be set using ResponseHeaderBag from the Symfony\Component\HttpFoundation\Response object.

Set new cookie value

use Symfony\Component\HttpFoundation\Cookie;

$cookie = new use Cookie('cookie_name', TRUE);
$response->headers->setCookie($cookie);
return $response;

Get cookies value

$request->cookies->get('cookie_name');