config>services.php

    'facebook'  => [
        'client_id'     => env('FACEBOOK_CLIENT_ID'),
        'client_secret' => env('FACEBOOK_CLIENT_SECRET'),
        'redirect'      => env('FACEBOOK_REDIRECT'),
    ],

    'google'    => [
        'client_id'     => env('GPlus_CLIENT_ID'),
        'client_secret' => env('Gplus_CLIENT_SECRET'),
        'redirect'      => env('GPlus_REDIRECT'),
    ],
-------------------------------------------------------------------------------------------------------------------------
web

Route::get('auth/{provider}', 'Auth\SocialAuthController@redirectToProvider')->name('social.auth');
Route::get('auth/{provider}/callback', 'Auth\SocialAuthController@handleProviderCallback')->name('provider.callback');

---------------------------------------------------------------------------------------------------------------------------
Controller>Auth>SocialAuthController

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

public function handleProviderCallback($provider)
    {
    $social_user = Socialite::driver($provider)->user();
   }

    public function authAndRedirect($user)
    {
        Auth::login($user);

        return redirect()->to('/bienvenido');
    }