fix: add minimum timeout to getQueryResults API requests

google/cloud/bigquery/client.py

@@ -94,6 +94,14 @@
 )
 _LIST_ROWS_FROM_QUERY_RESULTS_FIELDS = "jobReference,totalRows,pageToken,rows"
 
+# In microbenchmarks, it's been shown that even in ideal conditions (query
+# finished, local data), requests to getQueryResults can take 10+ seconds.
+# In less-than-ideal situations, the response can take even longer, as it must
+# be able to download a full 100+ MB row in that time. Don't let the
+# connection timeout before data can be downloaded.
+# https://github.com/googleapis/python-bigquery/issues/438
+_MIN_GET_QUERY_RESULTS_TIMEOUT = 120
+
 
 class Project(object):
     """Wrapper for resource describing a BigQuery project.
@@ -1580,6 +1588,9 @@ def _get_query_results(
 
         extra_params = {"maxResults": 0}
 
+        if timeout is not None:
+            timeout = max(timeout, _MIN_GET_QUERY_RESULTS_TIMEOUT)
+
         if project is None:
             project = self.project
 
@@ -3307,6 +3318,9 @@ def _list_rows_from_query_results(
             "location": location,
         }
 
+        if timeout is not None:
+            timeout = max(timeout, _MIN_GET_QUERY_RESULTS_TIMEOUT)
+
         if start_index is not None:
             params["startIndex"] = start_index
 

tests/unit/job/test_query.py

@@ -1046,6 +1046,8 @@ def test_result_invokes_begins(self):
         self.assertEqual(reload_request[1]["method"], "GET")
 
     def test_result_w_timeout(self):
+        import google.cloud.bigquery.client
+
         begun_resource = self._make_resource()
         query_resource = {
             "jobComplete": True,
@@ -1072,6 +1074,10 @@ def test_result_w_timeout(self):
             "/projects/{}/queries/{}".format(self.PROJECT, self.JOB_ID),
         )
         self.assertEqual(query_request[1]["query_params"]["timeoutMs"], 900)
+        self.assertEqual(
+            query_request[1]["timeout"],
+            google.cloud.bigquery.client._MIN_GET_QUERY_RESULTS_TIMEOUT,
+        )
         self.assertEqual(reload_request[1]["method"], "GET")
 
     def test_result_w_page_size(self):

tests/unit/test_client.py

@@ -311,7 +311,7 @@ def test__get_query_results_miss_w_explicit_project_and_timeout(self):
                     project="other-project",
                     location=self.LOCATION,
                     timeout_ms=500,
-                    timeout=42,
+                    timeout=420,
                 )
 
         final_attributes.assert_called_once_with({"path": path}, client, None)
@@ -320,7 +320,32 @@ def test__get_query_results_miss_w_explicit_project_and_timeout(self):
             method="GET",
             path=path,
             query_params={"maxResults": 0, "timeoutMs": 500, "location": self.LOCATION},
-            timeout=42,
+            timeout=420,
+        )
+
+    def test__get_query_results_miss_w_short_timeout(self):
+        import google.cloud.bigquery.client
+        from google.cloud.exceptions import NotFound
+
+        creds = _make_credentials()
+        client = self._make_one(self.PROJECT, creds)
+        conn = client._connection = make_connection()
+        path = "/projects/other-project/queries/nothere"
+        with self.assertRaises(NotFound):
+            client._get_query_results(
+                "nothere",
+                None,
+                project="other-project",
+                location=self.LOCATION,
+                timeout_ms=500,
+                timeout=1,
+            )
+
+        conn.api_request.assert_called_once_with(
+            method="GET",
+            path=path,
+            query_params={"maxResults": 0, "timeoutMs": 500, "location": self.LOCATION},
+            timeout=google.cloud.bigquery.client._MIN_GET_QUERY_RESULTS_TIMEOUT,
         )
 
     def test__get_query_results_miss_w_client_location(self):