Access-Control-Allow-Origin Multiple Origin Domains?

Question

Is there a way to allow multiple cross-domains using the Access-Control-Allow-Origin header?

I\'m aware of the *, but it is too open. I rea

Answer 1

Only a single origin can be specified for the Access-Control-Allow-Origin header. But you can set the origin in your response according to the request. Also don't forget to set the Vary header. In PHP I would do the following:

    /**
     * Enable CORS for the passed origins.
     * Adds the Access-Control-Allow-Origin header to the response with the origin that matched the one in the request.
     * @param array $origins
     * @return string|null returns the matched origin or null
     */
    function allowOrigins($origins)
    {
        $val = $_SERVER['HTTP_ORIGIN'] ?? null;
        if (in_array($val, $origins, true)) {
            header('Access-Control-Allow-Origin: '.$val);
            header('Vary: Origin');

            return $val;
        }

        return null;
    }

  if (allowOrigins(['http://localhost', 'https://localhost'])) {
      echo your response here, e.g. token
  }