7b3968d9b0
The rabbit backend now applies the [oslo_messaging_notifications]retry, [oslo_messaging_rabbit]rabbit_retry_interval, rabbit_retry_backoff and rabbit_interval_max configuration parameters when tries to establish the connection to the message bus during notification sending. This patch also clarifies the differences between the behavior of the kafka and the rabbit drivers in this regard. Closes-Bug: #1917645 Change-Id: Id4ccafc95314c86ae918336e42cca64a6acd4d94
140 lines
4.5 KiB
Python
140 lines
4.5 KiB
Python
# Copyright 2013 Red Hat, Inc.
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#
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# Licensed under the Apache License, Version 2.0 (the "License"); you may
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# not use this file except in compliance with the License. You may obtain
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# a copy of the License at
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#
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# http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
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# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
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# License for the specific language governing permissions and limitations
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# under the License.
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import abc
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import collections
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import threading
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from oslo_log import log as logging
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from oslo_utils import timeutils
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from oslo_messaging._drivers import common
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LOG = logging.getLogger(__name__)
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class Pool(object, metaclass=abc.ABCMeta):
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"""A thread-safe object pool.
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Modelled after the eventlet.pools.Pool interface, but designed to be safe
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when using native threads without the GIL.
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Resizing is not supported.
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"""
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def __init__(self, max_size=4, min_size=2, ttl=1200, on_expire=None):
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super(Pool, self).__init__()
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self._min_size = min_size
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self._max_size = max_size
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self._item_ttl = ttl
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self._current_size = 0
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self._cond = threading.Condition()
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self._items = collections.deque()
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self._on_expire = on_expire
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def expire(self):
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"""Remove expired items from left (the oldest item) to
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right (the newest item).
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"""
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with self._cond:
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while len(self._items) > self._min_size:
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try:
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ttl_watch, item = self._items.popleft()
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if ttl_watch.expired():
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self._on_expire and self._on_expire(item)
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self._current_size -= 1
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else:
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self._items.appendleft((ttl_watch, item))
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return
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except IndexError:
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break
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def put(self, item):
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"""Return an item to the pool."""
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with self._cond:
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ttl_watch = timeutils.StopWatch(duration=self._item_ttl)
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ttl_watch.start()
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self._items.append((ttl_watch, item))
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self._cond.notify()
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def get(self, retry=None):
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"""Return an item from the pool, when one is available.
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This may cause the calling thread to block.
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"""
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with self._cond:
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while True:
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try:
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ttl_watch, item = self._items.pop()
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self.expire()
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return item
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except IndexError:
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pass
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if self._current_size < self._max_size:
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self._current_size += 1
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break
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LOG.warning("Connection pool limit exceeded: "
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"current size %s surpasses max "
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"configured rpc_conn_pool_size %s",
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self._current_size, self._max_size)
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self._cond.wait()
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# We've grabbed a slot and dropped the lock, now do the creation
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try:
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return self.create(retry=retry)
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except Exception:
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with self._cond:
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self._current_size -= 1
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raise
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def iter_free(self):
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"""Iterate over free items."""
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while True:
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try:
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_, item = self._items.pop()
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yield item
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except IndexError:
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return
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@abc.abstractmethod
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def create(self, retry=None):
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"""Construct a new item."""
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class ConnectionPool(Pool):
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"""Class that implements a Pool of Connections."""
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def __init__(self, conf, max_size, min_size, ttl, url, connection_cls):
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self.connection_cls = connection_cls
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self.conf = conf
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self.url = url
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super(ConnectionPool, self).__init__(max_size, min_size, ttl,
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self._on_expire)
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def _on_expire(self, connection):
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connection.close()
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LOG.debug("Idle connection has expired and been closed."
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" Pool size: %d" % len(self._items))
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def create(self, purpose=common.PURPOSE_SEND, retry=None):
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LOG.debug('Pool creating new connection')
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return self.connection_cls(self.conf, self.url, purpose, retry=retry)
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def empty(self):
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for item in self.iter_free():
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item.close()
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