autotest (wifi): reduce flake in network_WiFi_ConnectionIdentifier
In some trials of network_WiFi_ConnectionIdentifier, we
see that the ID is zero. This is probably due to a race
condition.
Specifically: we attempt to read the connection
ID when assert_connect_wifi() returns. But I don't believe
that there is any guarantee that ActiveLinkMonitor has
successfully ARPed the gateway at this point.
To address this race, we poll the service properties until
ConnectionId is non-zero (or until we time out).
BUG=chromium:502522
TEST=network_WiFi_ConnectionIdentifier (10 iterations)
Of the 10 iterations, 8 passed. The two failures were for other
reasons. (I.e., none of the failures were due to "Connection
ID mismatched".)
Change-Id: I17afab31ff25c021e56f2991588728cdececad45
Reviewed-on: https://chromium-review.googlesource.com/280901
Reviewed-by: Paul Stewart <pstew@chromium.org>
Reviewed-by: mukesh agrawal <quiche@chromium.org>
Tested-by: mukesh agrawal <quiche@chromium.org>
Commit-Queue: mukesh agrawal <quiche@chromium.org>
Trybot-Ready: mukesh agrawal <quiche@chromium.org>
diff --git a/server/site_tests/network_WiFi_ConnectionIdentifier/network_WiFi_ConnectionIdentifier.py b/server/site_tests/network_WiFi_ConnectionIdentifier/network_WiFi_ConnectionIdentifier.py
index 6f86e86..cdea836 100644
--- a/server/site_tests/network_WiFi_ConnectionIdentifier/network_WiFi_ConnectionIdentifier.py
+++ b/server/site_tests/network_WiFi_ConnectionIdentifier/network_WiFi_ConnectionIdentifier.py
@@ -2,6 +2,9 @@
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
+import logging
+import time
+
from autotest_lib.client.common_lib import error
from autotest_lib.client.common_lib.cros.network import xmlrpc_datatypes
from autotest_lib.server.cros.network import hostap_config
@@ -12,8 +15,30 @@
"""Test for verifying connection identifier."""
version = 1
+ CONNECTION_ID_TIMEOUT_SECS = 10
SERVICE_PROPERTY_CONNECTION_ID = 'ConnectionId'
+ def _get_service_connection_id(self, ssid):
+ """Get the connection ID for a service.
+
+ Polls a service's properties until ConnectionId becomes non-zero,
+ or a timeout occurs.
+
+ @param ssid: SSID of the service of interest.
+ @raise TestError if a timeout occurs.
+ @return ConnectionId of the current service.
+ """
+ start_time = time.time()
+ while time.time() - start_time < self.CONNECTION_ID_TIMEOUT_SECS:
+ properties = self.context.client.shill.get_service_properties(ssid)
+ logging.debug('Service properties are: %s', properties)
+ connection_id = properties[self.SERVICE_PROPERTY_CONNECTION_ID]
+ if connection_id != 0:
+ return connection_id
+ time.sleep(1)
+ raise error.TestFail('ConnectionId remained zero')
+
+
def _connect(self, ssid, expected_connection_id=None):
"""Connect to an AP, and verify connection ID if it is specified.
@@ -23,11 +48,12 @@
"""
client_conf = xmlrpc_datatypes.AssociationParameters(ssid)
self.context.assert_connect_wifi(client_conf)
- properties = self.context.client.shill.get_service_properties(ssid)
- connection_id = properties[self.SERVICE_PROPERTY_CONNECTION_ID]
+ connection_id = self._get_service_connection_id(ssid)
if (expected_connection_id is not None and
expected_connection_id != connection_id):
- raise error.TestFail('Connection ID mismatched')
+ raise error.TestFail(
+ 'Expected connection ID %s, but got %s' % (
+ expected_connection_id, connection_id))
return connection_id
