Delete notification: Operation cannot be fulfilled on replicasets.extensions, the object has been modified

[hjacobs]

An exception occurs in v0.6 when --delete-notification is set to a value > 0 and a deployment with a TTL annotation is processed. Note that everything works (events emitted, resources deleted) and the annotations are set as expected, but the exception is a bit annoying:

kube-janitor-69f4484d9b-djc9m janitor 2019-03-23 22:20:28,730 INFO: Deployment nginx will be deleted at 2019-03-23T22:24:30Z (annotation janitor/ttl is set)
kube-janitor-69f4484d9b-djc9m janitor 2019-03-23 22:20:28,756 INFO: ReplicaSet nginx-dbddb74b8 will be deleted at 2019-03-23T22:24:30Z (annotation janitor/ttl is set)
kube-janitor-69f4484d9b-djc9m janitor 2019-03-23 22:20:28,773 ERROR: Failed to clean up: Operation cannot be fulfilled on replicasets.extensions "nginx-dbddb74b8": the object has been modified; please apply your changes to the latest version and try again
kube-janitor-69f4484d9b-djc9m janitor Traceback (most recent call last):
kube-janitor-69f4484d9b-djc9m janitor   File "/usr/local/lib/python3.7/site-packages/pykube/http.py", line 239, in raise_for_status
kube-janitor-69f4484d9b-djc9m janitor     resp.raise_for_status()
kube-janitor-69f4484d9b-djc9m janitor   File "/usr/local/lib/python3.7/site-packages/requests/models.py", line 940, in raise_for_status
kube-janitor-69f4484d9b-djc9m janitor     raise HTTPError(http_error_msg, response=self)
kube-janitor-69f4484d9b-djc9m janitor requests.exceptions.HTTPError: 409 Client Error: Conflict for url: https://10.3.0.1:443/apis/extensions/v1beta1/namespaces/default/replicasets/nginx-dbddb74b8
kube-janitor-69f4484d9b-djc9m janitor 
kube-janitor-69f4484d9b-djc9m janitor During handling of the above exception, another exception occurred:
kube-janitor-69f4484d9b-djc9m janitor 
kube-janitor-69f4484d9b-djc9m janitor Traceback (most recent call last):
kube-janitor-69f4484d9b-djc9m janitor   File "/kube_janitor/main.py", line 51, in run_loop
kube-janitor-69f4484d9b-djc9m janitor     dry_run=dry_run)
kube-janitor-69f4484d9b-djc9m janitor   File "/kube_janitor/janitor.py", line 231, in clean_up
kube-janitor-69f4484d9b-djc9m janitor     counter.update(handle_resource_on_ttl(resource, rules, delete_notification, dry_run))
kube-janitor-69f4484d9b-djc9m janitor   File "/kube_janitor/janitor.py", line 156, in handle_resource_on_ttl
kube-janitor-69f4484d9b-djc9m janitor     send_delete_notification(resource, reason, expiry_time, dry_run=dry_run)
kube-janitor-69f4484d9b-djc9m janitor   File "/kube_janitor/janitor.py", line 75, in send_delete_notification
kube-janitor-69f4484d9b-djc9m janitor     add_notification_flag(resource, dry_run=dry_run)
kube-janitor-69f4484d9b-djc9m janitor   File "/kube_janitor/janitor.py", line 52, in add_notification_flag
kube-janitor-69f4484d9b-djc9m janitor     resource.update()
kube-janitor-69f4484d9b-djc9m janitor   File "/usr/local/lib/python3.7/site-packages/pykube/objects.py", line 142, in update
kube-janitor-69f4484d9b-djc9m janitor     self.api.raise_for_status(r)
kube-janitor-69f4484d9b-djc9m janitor   File "/usr/local/lib/python3.7/site-packages/pykube/http.py", line 246, in raise_for_status
kube-janitor-69f4484d9b-djc9m janitor     raise HTTPError(resp.status_code, payload["message"])
kube-janitor-69f4484d9b-djc9m janitor pykube.exceptions.HTTPError: Operation cannot be fulfilled on replicasets.extensions "nginx-dbddb74b8": the object has been modified; please apply your changes to the latest version and try again
kube-janitor-69f4484d9b-djc9m janitor 2019-03-23 22:21:30,727 INFO: Clean up run completed: resources-processed=2941, deployments-with-ttl=1, replicasets-with-ttl=1
kube-janitor-69f4484d9b-djc9m janitor 2019-03-23 22:22:32,614 INFO: Clean up run completed: resources-processed=2941, deployments-with-ttl=1, replicasets-with-ttl=1
kube-janitor-69f4484d9b-djc9m janitor 2019-03-23 22:23:34,703 INFO: Clean up run completed: resources-processed=2941, deployments-with-ttl=1, replicasets-with-ttl=1
kube-janitor-69f4484d9b-djc9m janitor 2019-03-23 22:24:36,777 INFO: Deployment nginx with 10m TTL is 10m6s old and will be deleted (annotation janitor/ttl is set)
kube-janitor-69f4484d9b-djc9m janitor 2019-03-23 22:24:36,789 INFO: Deleting Deployment default/nginx..
kube-janitor-69f4484d9b-djc9m janitor 2019-03-23 22:24:36,808 INFO: ReplicaSet nginx-dbddb74b8 with 10m TTL is 10m6s old and will be deleted (annotation janitor/ttl is set)
kube-janitor-69f4484d9b-djc9m janitor 2019-03-23 22:24:36,817 INFO: Deleting ReplicaSet default/nginx-dbddb74b8..
kube-janitor-69f4484d9b-djc9m janitor 2019-03-23 22:24:36,834 INFO: Clean up run completed: resources-processed=2941, deployments-with-ttl=1, deployments-deleted=1, replicasets-with-ttl=1, replicasets-deleted=1

[hjacobs]

This probably happens because the deployment already propagates the new annotation to the replica set and kube-janitor needs to reload the replica set before attempting the update (which actually is a no-op in this case).

[blacs30]

The create_event function fails when the resource with the ttl is a namespace itself because the event is going to be created in the namespace which is being terminated, that is only for the ExpiryTimeReached event, the TimeToLiveExpired is written to the default namespace successfully.