Merge "Dismiss only specific failure in retry"

whitebox_neutron_tempest_plugin/common/utils.py

@@ -231,9 +231,17 @@ def remote_service_action(client, service, action):
     time.sleep(5)
 
 
-def retry_on_assert_fail(max_retries):
+# NOTE(mblue): Please use specific regex to avoid dismissing various issues
+def retry_on_assert_fail(max_retries,
+                         assert_regex,
+                         exception_type=AssertionError):
     """Decorator that retries a function up to max_retries times on asser fail
-    :param max_retries: The maximum number of retries before failing.
+    In order to avoid dismissing exceptions which lead to bugs,
+    obligatory regex checked in caught exception message,
+    also optional specific exception type can be passed.
+    :param max_retries: Obligatory maximum number of retries before failing.
+    :param assert_regex: Obligatory regex should be in exception message.
+    :param exception_type: Optional specific exception related to failure.
     """
     def decor(f):
         @functools.wraps(f)
@@ -242,7 +250,10 @@ def retry_on_assert_fail(max_retries):
             while retries < max_retries:
                 try:
                     return f(*args, **kwargs)
-                except AssertionError as e:
+                except exception_type as e:
+                    if not (re.search(assert_regex, str(e)) or
+                            re.search(assert_regex, repr(e))):
+                        raise
                     LOG.debug(
                         f"Assertion failed: {e}. Retrying ({retries + 1}/"
                         f"{max_retries})..."

whitebox_neutron_tempest_plugin/tests/scenario/test_qos.py

@@ -255,7 +255,10 @@ class QosBaseTest(test_qos.QoSTestMixin, base.TrafficFlowTest):
             raise self.skipException(
                 "iperf3 is not available on VM instance")
 
-    @utils.retry_on_assert_fail(max_retries=3)
+    # retry only when noticed measuring issue, as reported in BZ#2274465
+    @utils.retry_on_assert_fail(
+        max_retries=2,
+        assert_regex='not .* than')
     def _validate_bw_limit(self, client, server, egress=True, ipv6=False,
                            bw_limit=None, protocol=constants.PROTO_NAME_TCP):
         server_port = self.client.list_ports(

whitebox_neutron_tempest_plugin/tests/scenario/test_security_group_logging.py

@@ -509,7 +509,10 @@ class BaseSecGroupLoggingTest(
         self.check_log_ssh(
             should_log=True, hypervisor_ssh=vm_a['hv_ssh_client'])
 
-    @utils.retry_on_assert_fail(max_retries=3)
+    # retry only when network instability causes packet loss
+    @utils.retry_on_assert_fail(
+        max_retries=3,
+        assert_regex='0% packet loss" not found in output')
     def _test_only_accepted_traffic_logged(self):
         """This test verifies that only the log entries of allowed traffic
         exist when only the "allow" event is supposed to be logged