Since the pipeline state is stored in ZooKeeper, there could be cases
where the change_queues key is missing in the status json. This makes
API requests fail:
2022-02-22 17:56:18,390 ERROR cherrypy.error.139989033522128: [22/Feb/2022:17:56:18] HTTP
Traceback (most recent call last):
File "/opt/zuul/lib/python3.8/site-packages/cherrypy/_cprequest.py", line 638, in respond
self._do_respond(path_info)
File "/opt/zuul/lib/python3.8/site-packages/cherrypy/_cprequest.py", line 697, in _do_respond
response.body = self.handler()
File "/opt/zuul/lib/python3.8/site-packages/cherrypy/lib/encoding.py", line 223, in __call__
self.body = self.oldhandler(*args, **kwargs)
File "/opt/zuul/lib/python3.8/site-packages/cherrypy/lib/jsontools.py", line 59, in json_handler
value = cherrypy.serving.request._json_inner_handler(*args, **kwargs)
File "/opt/zuul/lib/python3.8/site-packages/cherrypy/_cpdispatch.py", line 54, in __call__
return self.callable(*self.args, **self.kwargs)
File "/opt/zuul/lib/python3.8/site-packages/zuul/web/__init__.py", line 1050, in status_change
return result_filter.filterPayload(payload)
File "/opt/zuul/lib/python3.8/site-packages/zuul/web/__init__.py", line 193, in filterPayload
for change_queue in pipeline['change_queues']:
KeyError: 'change_queues'
Fix this by using a .get() call rather than directly accessing the
dictionary key by name.
A similar issue was already fixed in [1].
[1]: https://review.opendev.org/c/zuul/zuul/+/829018
Change-Id: I947f58f02c3da7dad35d1fc186c7026800f7cbdd
8b7535b7a0