#!/usr/bin/env python
+# Copyright (C) The Arvados Authors. All rights reserved.
+#
+# SPDX-License-Identifier: AGPL-3.0
from __future__ import absolute_import, print_function
response to subscribers. It takes care of error handling, and retrying
requests with exponential backoff.
- To use this actor, define CLIENT_ERRORS and the _send_request method.
- If you also define an _item_key method, this class will support
- subscribing to a specific item by key in responses.
+ To use this actor, define the _send_request method. If you also
+ define an _item_key method, this class will support subscribing to
+ a specific item by key in responses.
"""
def __init__(self, client, timer_actor, poll_wait=60, max_poll_wait=180):
super(RemotePollLoopActor, self).__init__()
self._client = client
self._timer = timer_actor
- self._logger = logging.getLogger(self.LOGGER_NAME)
- self._later = self.actor_ref.proxy()
+ self._later = self.actor_ref.tell_proxy()
+ self._polling_started = False
self.min_poll_wait = poll_wait
self.max_poll_wait = max_poll_wait
self.poll_wait = self.min_poll_wait
- self.last_poll_time = None
self.all_subscribers = set()
self.key_subscribers = {}
if hasattr(self, '_item_key'):
self.subscribe_to = self._subscribe_to
+ def on_start(self):
+ self._logger = logging.getLogger("%s.%s" % (self.__class__.__name__, id(self.actor_urn[9:])))
+
def _start_polling(self):
- if self.last_poll_time is None:
- self.last_poll_time = time.time()
+ if not self._polling_started:
+ self._polling_started = True
self._later.poll()
def subscribe(self, subscriber):
self.all_subscribers.add(subscriber)
- self._logger.debug("%r subscribed to all events", subscriber)
+ self._logger.debug("%s subscribed to all events", subscriber.actor_ref.actor_urn)
self._start_polling()
# __init__ exposes this method to the proxy if the subclass defines
# _item_key.
def _subscribe_to(self, key, subscriber):
self.key_subscribers.setdefault(key, set()).add(subscriber)
- self._logger.debug("%r subscribed to events for '%s'", subscriber, key)
+ self._logger.debug("%s subscribed to events for '%s'", subscriber.actor_ref.actor_urn, key)
self._start_polling()
def _send_request(self):
def _got_error(self, error):
self.poll_wait = min(self.poll_wait * 2, self.max_poll_wait)
- self._logger.warning("Client error: %s - waiting %s seconds",
- error, self.poll_wait)
+ return "got error: {} - will try again in {} seconds".format(
+ error, self.poll_wait)
+
+ def is_common_error(self, exception):
+ return False
- def poll(self):
+ def poll(self, scheduled_start=None):
+ self._logger.debug("sending request")
start_time = time.time()
+ if scheduled_start is None:
+ scheduled_start = start_time
try:
response = self._send_request()
- except self.CLIENT_ERRORS as error:
- self.last_poll_time = start_time
- self._got_error(error)
+ except Exception as error:
+ errmsg = self._got_error(error)
+ if self.is_common_error(error):
+ self._logger.warning(errmsg)
+ else:
+ self._logger.exception(errmsg)
+ next_poll = start_time + self.poll_wait
else:
- self.last_poll_time += self.poll_wait
self._got_response(response)
- self._timer.schedule(self.last_poll_time + self.poll_wait,
- self._later.poll)
+ next_poll = scheduled_start + self.poll_wait
+ self._logger.info("got response with %d items in %s seconds, next poll at %s",
+ len(response), (time.time() - scheduled_start),
+ time.strftime('%Y-%m-%d %H:%M:%S', time.localtime(next_poll)))
+ end_time = time.time()
+ if next_poll < end_time: # We've drifted too much; start fresh.
+ next_poll = end_time + self.poll_wait
+ self._timer.schedule(next_poll, self._later.poll, next_poll)