Undefined index: avatar_url... with facebook socialite

[m2ura]

I modified the code on AuthController so can add more socialite providers buy changing public function redirectToProvider()
{
return Socialite::driver($github)->redirect();
}
to
public function redirectToProvider($provider)
{
return Socialite::driver($provider)->redirect();
}

here is a full code

public function redirectToProvider($provider)
{
return Socialite::driver($provider)->redirect();
}

/**
 * Obtain the user information from GitHub.
 *
 * @return Response
 */
public function handleProviderCallback($provider)
{
    $User = Socialite::driver($provider)->user();
    $user = $this->user->getByProviderId($User->id);

    if (auth()->check()) {
        $currentUser = auth()->user();

        if ($currentUser->provider_id) {
            return redirect()->back();
        } else {
            if ($user) {
                return redirect()->back();
            } else {
                $this->bindProvider($currentUser, $User);

                return redirect()->back();
            }
        }
    } else {
        if ($user) {
            auth()->loginUsingId($user->id);
            return redirect()->to('article');
        } else {
            $this->registerUser($User);
            return redirect()->to('auth/register');
        }
    }
}

/**
 * Bind the github account.
 *
 * @param $currentUser
 * @param $registerData
 * @return mixed
 */
public function bindProvider($currentUser, $registerData)
{
    $currentUser->provider_id = $registerData->user['id'];
    $currentUser->name = $registerData->nickname;
    $currentUser->url = $registerData->user['url'];

    return $currentUser->save();
}

/**
 * Save the register data in session.
 *
 * @param $registerData
 */
public function registerUser($registerData)
{
    $data['avatar'] = $registerData->user['avatar_url'];
    $data['provider_id'] = $registerData->user['id'];
    $data['url'] = $registerData->user['url'];
    $data['name'] = $registerData->nickname;
    $data['nickname'] = $registerData->user['name'];
    $data['email'] = $registerData->user['email'];

    session()->put('oauthData', $data);
}

/**
 * Display the github oauth for register page.
 *
 * @return \Illuminate\Contracts\View\Factory|\Illuminate\Http\RedirectResponse|\Illuminate\View\View
 */
public function create()
{
    if (! session()->has('oauthData')) {
        return redirect()->to('login');
    }

    $oauthData = array_merge(session('oauthData'), request()->old());

    return view('auth.register', compact('oauthData'));
}

/**
 * Store a new user.
 *
 * @return \Illuminate\Http\RedirectResponse|\Illuminate\Routing\Redirector
 */
public function store()
{
    if (! session()->has('oauthData')) {
        return redirect('login');
    }

    $this->validator(request()->all())->validate();

    $oauthData = session('oauthData');

    $data = array_merge($oauthData, request()->all());

    $data['password'] = bcrypt($data['password']);

    $data['status'] = true;

    auth()->guard()->login(User::create($data));

    session()->forget('oauthData');

    return redirect()->to('article');
}

But I get this

[m2ura]

this is my login form now

[jcc]

This error is 'Undefined index: avatar_url'. You need to modify the method of registerUser(). You try to run the code of dd($registerData) to see what in it. If you want to support login for facebook, you need to modify the code.I had only supported login with github.