OauthService.php

<?php

namespace SE\AppBundle\Service;

use Symfony\Component\DependencyInjection\ContainerInterface;
use Symfony\Component\HttpFoundation\Request;
use Symfony\Component\HttpFoundation\Response;
use Symfony\Component\HttpFoundation\Cookie;

class OAuthService
{
    private $container;

    private $request;

    public function __construct(ContainerInterface $container, Request $request)
    {
        $this->container = $container;
        $this->request = $request;
    }

    private function expireSoon($oauth)
    {
        if (isset($oauth->expire_at) && time() > ($oauth->expire_at - 600)) {
            return true;
        }

        return false;
    }

    public function getAccessToken()
    {
        $browser = $this->container->get('buzz');

        $oauth_url = $this->container->getParameter('api.oauth');
        $public_id = $this->container->getParameter('api.public_id');
        $secret = $this->container->getParameter('api.secret');

        // Get actual token

        $oauth = json_decode($this->request->cookies->get('oauth'));
        $access_token = null;

        if ($oauth) {
            $access_token = $oauth->access_token;
        }

        // If access_token will expire soon
        if ($this->expireSoon($oauth) && property_exists($oauth, 'refresh_token')) {
            $response = $browser->get("{$oauth_url}?client_id={$public_id}&client_secret={$secret}&grant_type=refresh_token&refresh_token={$oauth->refresh_token}");

            $response = json_decode($response->getContent());

            if (property_exists($response, 'access_token')) {
                $oauth = $response;
                $access_token = $response->access_token;

                // add the expire date value to $oauth array

                $oauth = get_object_vars($oauth);
                $oauth['expire_at'] = time() + 3600;

                // store access token information in a cookie

                $cookie = new Cookie('oauth', json_encode($oauth));
                $response = new Response();
                $response->headers->setCookie($cookie);
                $response->send();
            }
        } else {

            // If no user logged
            if (!$this->container->get('security.authorization_checker')->isGranted('ROLE_USER')) {

                // If access_token does not exist
                if (!$oauth) {

                    // Create an anonymous accessToken

                    $response = $browser->get("{$oauth_url}?client_id={$public_id}&client_secret={$secret}&grant_type=client_credentials");

                    $response = json_decode($response->getContent());

                    if (property_exists($response, 'access_token')) {
                        $oauth = $response;
                        $access_token = $response->access_token;

                        // add the expire date value to $oauth array

                        $oauth = get_object_vars($oauth);
                        $oauth['expire_at'] = time() + 3600;

                        // store access token information in a cookie

                        $cookie = new Cookie('oauth', json_encode($oauth), time() + 3600);
                        $response = new Response();
                        $response->headers->setCookie($cookie);
                        $response->send();
                    }
                }
            }
            // If user is logged
            else {
                $user = $this->container->get('security.token_storage')->getToken()->getUser();

                // If accessToken does NOT exist OR will expire soon OR is anonymous
                if (!$oauth) {

                    // Create an accessToken with an identity

                    $response = $browser->get("{$oauth_url}?grant_type=http://oauth2.dev/grants/api_key&client_id={$public_id}&client_secret={$secret}&api_key={$user->getApiKey()}");

                    $response = json_decode($response->getContent());

                    if (property_exists($response, 'access_token')) {
                        $oauth = $response;
                        $access_token = $response->access_token;

                        // add the expire date value to $oauth array
                        $oauth = get_object_vars($oauth);
                        $oauth['expire_at'] = time() + 3600;

                        // store access token information in a cookie

                        $cookie = new Cookie('oauth', json_encode($oauth));
                        $response = new Response();
                        $response->headers->setCookie($cookie);
                        $response->send();
                    }
                }
            }
        }

        return $access_token;
    }
}