As you maybe know Drupal 8 is almost ready to be released, could be in next DrupalCon Europe held in Barcelona.

However, if you are interested in CORS applications you must wait until Drupal 8.1 to get native support to CORS in Drupal more information at issue.

A long time ago I wrote the article How to enable CORS requests against Drupal 8 but that approach only works in environments using Apache Web Server, but in servers using a non-Apache web server like Nginx that solution is useless. Today I face that problem with Pantheon.

Therefore, I implemented a solution hacking the file index.php to enable CORS. Let me split the change into two stages.

Firstly we have to guarantee the REST method OPTIONS return the proper value because Drupal 8 can’t handle that request right now, check the code to implement that

  if ($_SERVER['REQUEST_METHOD'] == 'OPTIONS') {
    $response = new Response(200);
    $response->headers->set('Access-Control-Allow-Origin', '*');
    $response->headers->set('Access-Control-Allow-Methods',
   'POST, GET, OPTIONS, PATCH, DELETE');
    $response->headers->set('Access-Control-Allow-Headers',
   'Authorization');
    $response->send();
    exit;
  }

Secondly, we have to modify normal requests to enable remote requests from any source desired, as you can see in the following snippet of code

  $response = $kernel
      ->handle($request)
      // Handle the response object.
      ->prepare($request);

  // Enable CORS requests, Change '*' for any specific domain or ip address
  $response->headers->set('Access-Control-Allow-Origin', '*');
  $response->headers->set('Access-Control-Allow-Methods', 
  'POST, GET, OPTIONS, PATCH, DELETE');
  $response->headers->set('Access-Control-Allow-Headers', 
  'Authorization');

You can apply this patch against Drupal 8 beta 10.

I know there are initiatives to enable this feature using contributed modules, but meanwhile, we get a definite solution, this is temporary solution flexible enough using Drupal 8 style to start using Drupal as backend in a Decoupled solution.

I hope you found this post useful.