How to know if user is logged to Facebook? Laravel Socialite

Question

I setup a middleware on a route so that if anyone browses to it, they should be logged to facebook first, if not they'll be redirected to facebook:

Route::get( '/events/facebook', 'EventsController@facebookEvents' )->middleware('CheckFB');

It works fine, however, now the route keeps redirecting back to Facebook over and over.

This is the middleware:

/**
 * Handle an incoming request.
 *
 * @param  \Illuminate\Http\Request  $request
 * @param  \Closure  $next
 * @return mixed
 */
public function handle($request, Closure $next, $provider=null)
{  
    $provider = 'facebook';
    $this->validateProvider($provider);

    if ($provider === 'facebook') {
        return Socialite::driver($provider)->scopes([
            'email',
            'public_profile',
            'rsvp_event',
            'user_birthday',
            'user_events',
            'user_friends',
        ])->redirect();
    }

    return Socialite::driver($provider)->redirect();
}

What I want is that if the user is already logged, he shouldn't be redirected! only the first once.

I tried this:

$user = Socialite::driver('facebook')->user();

But it makes this error:

GuzzleHttp \ Exception \ ClientException (400) Client error: POST https://graph.facebook.com/v2.10/oauth/access_token resulted in a 400 Bad Request response: {"error":{"message":"This authorization code has been used.","type":"OAuthException","code":100,"fbtrace_id":"*** (truncated...)

Answer 1

Im using Auth::check(); to know if an user is logged

use App\User;
use Auth;
use Socialite;
use Redirect;

The method recives as param a $service in this case Facebook

//route to handle the callback
Route::get('/callback/{service}', 'SocialAuthController@handleProviderCallback');


public function handleProviderCallback($service)
{

    if(Auth::check())//if user is logged
    {
        $user_id = Auth::id(); //you get the user ID
        $authUser = User::where('id', $user_id)->first(); //you should find the user in the User table 
        $user_service = $authUser->service; //I saved in the database the service used to log in, so I call it
        return view ( 'home' )->withDetails ( $authUser )->withService ( $user_service ); //then I return the view with the details
    }else //if user is not login in
    {
        $user = Socialite::driver( $service )->user();
        $authUser = $this->findOrCreateUser($user, $service);//personal method to know if the user is new or it is already saved on DB
        Auth::login($authUser, true);//Login if the authUser return is true
        return view ( 'home' )->withDetails ( $user )->withService ( $service );
    }

Hope it works for you!