Monitoring system tests: Collision on group.create

[tseaver]

From: https://travis-ci.org/GoogleCloudPlatform/gcloud-python/builds/151551907#L1081-L1091

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ERROR: test_list_group_members (monitoring.TestMonitoringGroups)
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Traceback (most recent call last):
  File "/home/travis/build/GoogleCloudPlatform/gcloud-python/system_tests/monitoring.py", line 263, in test_list_group_members
    group.create()
  File "/home/travis/build/GoogleCloudPlatform/gcloud-python/.tox/system-tests3/lib/python3.4/site-packages/gcloud/monitoring/group.py", line 178, in create
    method='POST', path=path, data=self._to_dict())
  File "/home/travis/build/GoogleCloudPlatform/gcloud-python/.tox/system-tests3/lib/python3.4/site-packages/gcloud/connection.py", line 347, in api_request
    error_info=method + ' ' + url)
gcloud.exceptions.ServiceUnavailable: 503 Write collision, please retry. (POST https://monitoring.googleapis.com/v3/projects/precise-truck-742/groups/)

[dhermes]

@rimey Can you weigh in here?

[tseaver]

Smells like we just need to add a RetryErrors(ServiceUnavailable) here.

[tseaver]

I think #2095 addresses this error.

[rimey]

@dhermes I'm having trouble assigning this issue to @supriyagarg. Does she need to be a member of GoogleCloudPlatform?

[rimey]

I think she needs to be a member of the GoogleCloudPlatform "Contributors" team.

[rimey]

See my comment on #2092. This error is slightly surprising. Let's find out more about in exactly what circumstances it occurs, and whether it is deterministic.

[dhermes]

Closed by #2095