WordPress

<?php

namespace App\Controller;

use KnpU\OAuth2ClientBundle\Client\Provider\GoogleClient;
use League\OAuth2\Client\Provider\GoogleUser;
use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;
use Symfony\Component\Routing\Annotation\Route;
use KnpU\OAuth2ClientBundle\Client\ClientRegistry;
use League\OAuth2\Client\Provider\Exception\IdentityProviderException;
use Symfony\Component\HttpFoundation\Request;

class GoogleController extends AbstractController
{
    /**
     * Link to this controller to start the "connect" process
     *
     * @Route("/connect/google", name="connect_google_start")
     */
    public function connectAction(ClientRegistry $clientRegistry)
    {
        // on Symfony 3.3 or lower, $clientRegistry = $this->get('knpu.oauth2.registry');

        // will redirect to Facebook!
        return $clientRegistry
            ->getClient('google') // key used in config/packages/knpu_oauth2_client.yaml
            ->redirect([
                'profile', 'email' // the scopes you want to access
            ])
            ;
    }

    /**
     * After going to Facebook, you're redirected back here
     * because this is the "redirect_route" you configured
     * in config/packages/knpu_oauth2_client.yaml
     *
     * @Route("/connect/google/check", name="connect_google_check")
     */
    public function connectCheckAction(Request $request, ClientRegistry $clientRegistry)
    {
        // ** if you want to *authenticate* the user, then
        // leave this method blank and create a Guard authenticator
        // (read below)

        /** @var GoogleClient $client */
        $client = $clientRegistry->getClient('google');

        try {
            // the exact class depends on which provider you're using
            /** @var GoogleUser $user */
            $user = $client->fetchUser();

            // do something with all this new power!
            // e.g. $name = $user->getFirstName();
            dump($user); die;
            // ...
        } catch (IdentityProviderException $e) {
            // something went wrong!
            // probably you should return the reason to the user
            dump(/*$e->getMessage().*/"An error occured. Please try again later"); die;
        }
    }
}