X-Git-Url: https://git.arvados.org/arvados.git/blobdiff_plain/7f7ed63314bec77bf93edc233514c50a1030cac4..a05e443dbfcde94651afe783e633b08d79e2b6d1:/sdk/python/arvados/events.py diff --git a/sdk/python/arvados/events.py b/sdk/python/arvados/events.py index 81a9b36182..e53e4980a8 100644 --- a/sdk/python/arvados/events.py +++ b/sdk/python/arvados/events.py @@ -1,11 +1,20 @@ +# Copyright (C) The Arvados Authors. All rights reserved. +# +# SPDX-License-Identifier: Apache-2.0 + +from __future__ import absolute_import +from future import standard_library +standard_library.install_aliases() +from builtins import str +from builtins import object import arvados -import config -import errors -from retry import RetryLoop +from . import config +from . import errors +from .retry import RetryLoop import logging import json -import thread +import _thread import threading import time import os @@ -115,21 +124,22 @@ class EventClient(object): self.on_event_cb(m) except Exception as e: _logger.exception("Unexpected exception from event callback.") - thread.interrupt_main() + _thread.interrupt_main() def on_closed(self): if not self.is_closed.is_set(): - _logger.warn("Unexpected close. Reconnecting.") + _logger.warning("Unexpected close. Reconnecting.") for tries_left in RetryLoop(num_retries=25, backoff_start=.1, max_wait=15): try: self._setup_event_client() + _logger.warning("Reconnect successful.") break except Exception as e: - _logger.warn("Error '%s' during websocket reconnect.", e) + _logger.warning("Error '%s' during websocket reconnect.", e) if tries_left == 0: _logger.exception("EventClient thread could not contact websocket server.") self.is_closed.set() - thread.interrupt_main() + _thread.interrupt_main() return def run_forever(self): @@ -153,40 +163,77 @@ class PollClient(threading.Thread): self._closing = threading.Event() self._closing_lock = threading.RLock() - def run(self): - self.id = 0 if self.last_log_id != None: - self.id = self.last_log_id + # Caller supplied the last-seen event ID from a previous + # connection. + self._skip_old_events = [["id", ">", str(self.last_log_id)]] else: - for f in self.filters: - for tries_left in RetryLoop(num_retries=25, backoff_start=.1, max_wait=self.poll_time): - try: - items = self.api.logs().list(limit=1, order="id desc", filters=f).execute()['items'] - break - except errors.ApiError as error: - pass - else: - tries_left = 0 - break - if tries_left == 0: - _logger.exception("PollClient thread could not contact API server.") - with self._closing_lock: - self._closing.set() - thread.interrupt_main() - return - if items: - if items[0]['id'] > self.id: - self.id = items[0]['id'] + # We need to do a reverse-order query to find the most + # recent event ID (see "if not self._skip_old_events" + # in run()). + self._skip_old_events = False + def run(self): self.on_event({'status': 200}) while not self._closing.is_set(): - max_id = self.id moreitems = False for f in self.filters: for tries_left in RetryLoop(num_retries=25, backoff_start=.1, max_wait=self.poll_time): try: - items = self.api.logs().list(order="id asc", filters=f+[["id", ">", str(self.id)]]).execute() + if not self._skip_old_events: + # If the caller didn't provide a known + # recent ID, our first request will ask + # for the single most recent event from + # the last 2 hours (the time restriction + # avoids doing an expensive database + # query, and leaves a big enough margin to + # account for clock skew). If we do find a + # recent event, we remember its ID but + # then discard it (we are supposed to be + # returning new/current events, not old + # ones). + # + # Subsequent requests will get multiple + # events in chronological order, and + # filter on that same cutoff time, or + # (once we see our first matching event) + # the ID of the last-seen event. + # + # Note: self._skip_old_events must not be + # set until the threshold is decided. + # Otherwise, tests will be unreliable. + filter_by_time = [[ + "created_at", ">=", + time.strftime( + "%Y-%m-%dT%H:%M:%SZ", + time.gmtime(time.time()-7200))]] + items = self.api.logs().list( + order="id desc", + limit=1, + filters=f+filter_by_time).execute() + if items["items"]: + self._skip_old_events = [ + ["id", ">", str(items["items"][0]["id"])]] + items = { + "items": [], + "items_available": 0, + } + else: + # No recent events. We can keep using + # the same timestamp threshold until + # we receive our first new event. + self._skip_old_events = filter_by_time + else: + # In this case, either we know the most + # recent matching ID, or we know there + # were no matching events in the 2-hour + # window before subscribing. Either way we + # can safely ask for events in ascending + # order. + items = self.api.logs().list( + order="id asc", + filters=f+self._skip_old_events).execute() break except errors.ApiError as error: pass @@ -197,11 +244,10 @@ class PollClient(threading.Thread): _logger.exception("PollClient thread could not contact API server.") with self._closing_lock: self._closing.set() - thread.interrupt_main() + _thread.interrupt_main() return for i in items["items"]: - if i['id'] > max_id: - max_id = i['id'] + self._skip_old_events = [["id", ">", str(i["id"])]] with self._closing_lock: if self._closing.is_set(): return @@ -209,10 +255,9 @@ class PollClient(threading.Thread): self.on_event(i) except Exception as e: _logger.exception("Unexpected exception from event callback.") - thread.interrupt_main() + _thread.interrupt_main() if items["items_available"] > len(items["items"]): moreitems = True - self.id = max_id if not moreitems: self._closing.wait(self.poll_time) @@ -262,7 +307,7 @@ def _subscribe_websocket(api, filters, on_event, last_log_id=None): try: client = EventClient(uri_with_token, filters, on_event, last_log_id) except Exception: - _logger.warn("Failed to connect to websockets on %s" % endpoint) + _logger.warning("Failed to connect to websockets on %s" % endpoint) raise else: return client @@ -291,7 +336,7 @@ def subscribe(api, filters, on_event, poll_fallback=15, last_log_id=None): else: _logger.info("Using polling because ARVADOS_DISABLE_WEBSOCKETS is true") except Exception as e: - _logger.warn("Falling back to polling after websocket error: %s" % e) + _logger.warning("Falling back to polling after websocket error: %s" % e) p = PollClient(api, filters, on_event, poll_fallback, last_log_id) p.start() return p