Move refresh_id_token to validator function

oauthlib/openid/connect/core/grant_types/refresh_token.py

@@ -15,8 +15,7 @@
 
 class RefreshTokenGrant(GrantTypeBase):
 
-    def __init__(self, refresh_id_token=True, request_validator=None, **kwargs):
-        self.refresh_id_token = refresh_id_token
+    def __init__(self, request_validator=None, **kwargs):
         self.proxy_target = OAuth2RefreshTokenGrant(
             request_validator=request_validator, **kwargs)
         self.register_token_modifier(self.add_id_token)
@@ -29,8 +28,7 @@ def add_id_token(self, token, token_handler, request):
         The authorization_code version of this method is used to
         retrieve the nonce accordingly to the code storage.
         """
-        # Treat it as normal OAuth 2 auth code request if openid is not present
-        if not self.refresh_id_token:
+        if not self.request_validator.refresh_id_token(request):
             return token
 
         return super().add_id_token(token, token_handler, request)

oauthlib/openid/connect/core/request_validator.py

@@ -306,3 +306,15 @@ def get_userinfo_claims(self, request):
         Method is used by:
             UserInfoEndpoint
         """
+
+    def refresh_id_token(self, request):
+        """Whether the id token should be refreshed. Default, True
+
+        :param request: OAuthlib request.
+        :type request: oauthlib.common.Request
+        :rtype: True or False
+
+        Method is used by:
+            RefreshTokenGrant
+        """
+        return True

tests/openid/connect/core/grant_types/test_refresh_token.py

@@ -60,9 +60,12 @@ def test_refresh_id_token(self):
         self.assertIn('token_type', token)
         self.assertIn('expires_in', token)
         self.assertEqual(token['scope'], 'hello openid')
+        self.mock_validator.refresh_id_token.assert_called_once_with(
+            self.request
+        )
 
     def test_refresh_id_token_false(self):
-        self.auth.refresh_id_token = False
+        self.mock_validator.refresh_id_token.return_value = False
         self.mock_validator.get_original_scopes.return_value = [
             'hello', 'openid'
         ]
@@ -80,6 +83,9 @@ def test_refresh_id_token_false(self):
         self.assertIn('expires_in', token)
         self.assertEqual(token['scope'], 'hello openid')
         self.assertNotIn('id_token', token)
+        self.mock_validator.refresh_id_token.assert_called_once_with(
+            self.request
+        )
 
     def test_refresh_token_without_openid_scope(self):
         self.request.scope = "hello"