Add option to controls whether a user should be created or not when a new user is logging in through Oauth

Author: joyceverheije

config/oauth.php

@@ -15,6 +15,17 @@
      */
     'providers' => ['google'],
 
+    /*
+    |--------------------------------------------------------------------------
+    | This boolean controls whether a user should be created or not
+    | when a new user is logging in through Oauth
+    |--------------------------------------------------------------------------
+    |
+    | Possible values: true, false
+    |
+     */
+    'create_user_with_default_role' => true,
+
     /*
     |--------------------------------------------------------------------------
     | New user default role name (legacy)

src/Http/Controllers/Admin/LoginController.php

@@ -240,6 +240,12 @@ public function handleProviderCallback($provider, OauthRequest $request)
                 return $this->afterAuthentication($request, $user);
             }
         } else {
+            if (!config('twill.oauth.create_user_with_default_role', true)) {
+                return $this->redirector->to(route('twill.login'))->withErrors([
+                    'error' => __('auth.failed'),
+                ]);
+            }
+
             // If the user doesn't exist, create it
             $user = $repository->oauthCreateUser($oauthUser);
             $user->linkProvider($oauthUser, $provider);