kuryr-kubernetes/kuryr_kubernetes/controller/handlers/pipeline.py
Maysa Macedo 11ccc66118 Prevent Kuryr restart due to connection issue
In case the connection to Keystone is broken Kuryr controller is instantly
restarted. This may result in leftovers loadbalancers as a Kubernetes
service deletion can happen while the lbaas is still in PENDING_CREATE
and if the controller is restarted, the deletion event will be gone.
In this commit we give Kuryr a chance to retry the event before restarting.

Change-Id: Ie2cacc86e745bbd7da7254f7adfd9b41370936ab
Closes-bug: 1853460
2019-11-21 17:01:45 +00:00

70 lines
2.9 KiB
Python

# Copyright (c) 2016 Mirantis, Inc.
# All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
from requests import exceptions as requests_exc
from keystoneauth1 import exceptions as key_exc
from kuryr_kubernetes import exceptions
from kuryr_kubernetes.handlers import asynchronous as h_async
from kuryr_kubernetes.handlers import dispatch as h_dis
from kuryr_kubernetes.handlers import k8s_base as h_k8s
from kuryr_kubernetes.handlers import logging as h_log
from kuryr_kubernetes.handlers import retry as h_retry
class ControllerPipeline(h_dis.EventPipeline):
"""Serves as an entry point for controller Kubernetes events.
`ControllerPipeline` is an entry point handler for the Kuryr-Kubernetes
controller. `ControllerPipeline` allows registering
:class:`kuryr_kubernetes.handlers.k8s_base.ResourceEventHandler`s and
ensures the proper handler is called for each event that is passed to the
`ControllerPipeline`. Also it ensures the following behavior:
- multiple `ResourceEventHandler`s can be registered for the same
resource type (`OBJECT_KIND`)
- failing handlers (i.e. ones that raise `Exception`s) are retried
until either the handler succeeds or a finite amount of time passes,
in which case the most recent exception is logged
- in case there are multiple handlers registered for the same resource
type, all such handlers are considered independent (i.e. if one
handler fails, other handlers will still be called regardless; and the
order in which such handlers are called is not determined)
- events for different Kubernetes objects can be handled concurrently
- events for the same Kubernetes object are handled sequentially in
the order of arrival
"""
def __init__(self, thread_group):
self._tg = thread_group
super(ControllerPipeline, self).__init__()
def _wrap_consumer(self, consumer):
# TODO(ivc): tune retry interval/timeout
return h_log.LogExceptions(h_retry.Retry(
consumer, exceptions=(
exceptions.ResourceNotReady,
key_exc.connection.ConnectFailure,
requests_exc.ConnectionError)))
def _wrap_dispatcher(self, dispatcher):
return h_log.LogExceptions(h_async.Async(dispatcher, self._tg,
h_k8s.object_uid))