Fix key repository failover for HTTP server errors

atlassian_jwt_auth/key.py

@@ -104,7 +104,7 @@ def retrieve(
             return self._retrieve(url, requests_kwargs)
         except requests.RequestException as e:
             try:
-                status_code = e.response.status_code if e.response else None
+                status_code = e.response.status_code if e.response is not None else None
             except AttributeError:
                 status_code = None
             raise PublicKeyRetrieverException(e, status_code=status_code)

atlassian_jwt_auth/tests/test_public_key_provider.py

@@ -6,6 +6,7 @@
 import httptest
 import requests
 
+from atlassian_jwt_auth.exceptions import PublicKeyRetrieverException
 from atlassian_jwt_auth.key import (
     PEM_FILE_TYPE,
     HTTPSMultiRepositoryPublicKeyRetriever,
@@ -274,6 +275,42 @@ def test_retrieve_with_connection_error(self, mock_get_method):
         self.assertEqual(retriever.retrieve("example/eg"), self._public_key_pem)
 
 
+class HTTPErrorStatusTest(unittest.TestCase):
+    @mock.patch.object(requests.Session, "get")
+    def test_server_error_tries_next_repository(self, mock_get):
+        error = requests.Response()
+        error.status_code = 503
+        success = requests.Response()
+        success.status_code = 200
+        success.headers["content-type"] = PEM_FILE_TYPE
+        success._content = b"public-key"
+        mock_get.side_effect = [error, success]
+        retriever = HTTPSMultiRepositoryPublicKeyRetriever(
+            ["https://first.example", "https://second.example"]
+        )
+
+        self.assertEqual(retriever.retrieve("example/key"), "public-key")
+        self.assertEqual(mock_get.call_count, 2)
+        self.assertEqual(
+            mock_get.call_args.args[0], "https://second.example/example/key"
+        )
+
+    @mock.patch.object(requests.Session, "get")
+    def test_client_error_preserves_status_without_failover(self, mock_get):
+        response = requests.Response()
+        response.status_code = 403
+        mock_get.return_value = response
+        retriever = HTTPSMultiRepositoryPublicKeyRetriever(
+            ["https://first.example", "https://second.example"]
+        )
+
+        with self.assertRaises(PublicKeyRetrieverException) as caught:
+            retriever.retrieve("example/key")
+        self.assertEqual(caught.exception.status_code, 403)
+        self.assertIs(caught.exception.original_exception.response, response)
+        mock_get.assert_called_once()
+
+
 def _setup_mock_response_for_retriever(mock_method, public_key_pem, headers=None):
     """returns a setup mock response for use with a https public key
     retriever.