From 6ae1145f5e980a47ac2b1ff3afa228a5da3f6e70 Mon Sep 17 00:00:00 2001 From: Johnson Shi Date: Thu, 25 Mar 2021 07:20:10 -0700 Subject: Azure helper: Ensure Azure http handler sleeps between retries (#842) Ensure that the Azure helper's http handler sleeps a fixed duration between retry failure attempts. The http handler will sleep a fixed duration between failed attempts regardless of whether the attempt failed due to (1) request timing out or (2) instant failure (no timeout). Due to certain platform issues, the http request to the Azure endpoint may instantly fail without reaching the http timeout duration. Without sleeping a fixed duration in between retry attempts, the http handler will loop through the max retry attempts quickly. This causes the communication between cloud-init and the Azure platform to be less resilient due to the short total duration if there is no sleep in between retries. --- tests/unittests/test_datasource/test_azure_helper.py | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) (limited to 'tests') diff --git a/tests/unittests/test_datasource/test_azure_helper.py b/tests/unittests/test_datasource/test_azure_helper.py index b8899807..63482c6c 100644 --- a/tests/unittests/test_datasource/test_azure_helper.py +++ b/tests/unittests/test_datasource/test_azure_helper.py @@ -384,6 +384,7 @@ class TestAzureHelperHttpWithRetries(CiTestCase): max_readurl_attempts = 240 default_readurl_timeout = 5 + sleep_duration_between_retries = 5 periodic_logging_attempts = 12 def setUp(self): @@ -394,8 +395,8 @@ class TestAzureHelperHttpWithRetries(CiTestCase): self.m_readurl = patches.enter_context( mock.patch.object( azure_helper.url_helper, 'readurl', mock.MagicMock())) - patches.enter_context( - mock.patch.object(azure_helper.time, 'sleep', mock.MagicMock())) + self.m_sleep = patches.enter_context( + mock.patch.object(azure_helper.time, 'sleep', autospec=True)) def test_http_with_retries(self): self.m_readurl.return_value = 'TestResp' @@ -438,6 +439,12 @@ class TestAzureHelperHttpWithRetries(CiTestCase): self.m_readurl.call_count, self.periodic_logging_attempts + 1) + # Ensure that cloud-init did sleep between each failed request + self.assertEqual( + self.m_sleep.call_count, + self.periodic_logging_attempts) + self.m_sleep.assert_called_with(self.sleep_duration_between_retries) + def test_http_with_retries_long_delay_logs_periodic_failure_msg(self): self.m_readurl.side_effect = \ [SentinelException] * self.periodic_logging_attempts + \ -- cgit v1.2.3