diff --git a/synapse/crypto/keyring.py b/synapse/crypto/keyring.py index 3fb99f712..828aced44 100644 --- a/synapse/crypto/keyring.py +++ b/synapse/crypto/keyring.py @@ -22,6 +22,8 @@ from syutil.crypto.signing_key import ( from syutil.base64util import decode_base64, encode_base64 from synapse.api.errors import SynapseError, Codes +from synapse.util.retryutils import get_retry_limiter + from OpenSSL import crypto import logging @@ -87,12 +89,18 @@ class Keyring(object): return # Try to fetch the key from the remote server. - # TODO(markjh): Ratelimit requests to a given server. - (response, tls_certificate) = yield fetch_server_key( - server_name, self.hs.tls_context_factory + limiter = yield get_retry_limiter( + server_name, + self.clock, + self.store, ) + with limiter: + (response, tls_certificate) = yield fetch_server_key( + server_name, self.hs.tls_context_factory + ) + # Check the response. x509_certificate_bytes = crypto.dump_certificate( diff --git a/synapse/federation/federation_client.py b/synapse/federation/federation_client.py index 6042e366b..cd3c962d5 100644 --- a/synapse/federation/federation_client.py +++ b/synapse/federation/federation_client.py @@ -24,6 +24,8 @@ from synapse.util.expiringcache import ExpiringCache from synapse.util.logutils import log_function from synapse.events import FrozenEvent +from synapse.util.retryutils import get_retry_limiter, NotRetryingDestination + import logging @@ -183,24 +185,32 @@ class FederationClient(FederationBase): pdu = None for destination in destinations: try: - transaction_data = yield self.transport_layer.get_event( - destination, event_id + limiter = yield get_retry_limiter( + destination, + self._clock, + self.store, ) - logger.debug("transaction_data %r", transaction_data) + with limiter: + transaction_data = yield self.transport_layer.get_event( + destination, event_id + ) - pdu_list = [ - self.event_from_pdu_json(p, outlier=outlier) - for p in transaction_data["pdus"] - ] + logger.debug("transaction_data %r", transaction_data) - if pdu_list: - pdu = pdu_list[0] + pdu_list = [ + self.event_from_pdu_json(p, outlier=outlier) + for p in transaction_data["pdus"] + ] - # Check signatures are correct. - pdu = yield self._check_sigs_and_hash(pdu) + if pdu_list: + pdu = pdu_list[0] + + # Check signatures are correct. + pdu = yield self._check_sigs_and_hash(pdu) + + break - break except SynapseError: logger.info( "Failed to get PDU %s from %s because %s", @@ -216,6 +226,9 @@ class FederationClient(FederationBase): event_id, destination, e, ) continue + except NotRetryingDestination as e: + logger.info(e.message) + continue except Exception as e: logger.info( "Failed to get PDU %s from %s because %s", diff --git a/synapse/federation/transaction_queue.py b/synapse/federation/transaction_queue.py index 6faaa066f..a77201ad4 100644 --- a/synapse/federation/transaction_queue.py +++ b/synapse/federation/transaction_queue.py @@ -22,6 +22,9 @@ from .units import Transaction from synapse.api.errors import HttpResponseException from synapse.util.logutils import log_function from synapse.util.logcontext import PreserveLoggingContext +from synapse.util.retryutils import ( + get_retry_limiter, NotRetryingDestination, +) import logging @@ -147,25 +150,6 @@ class TransactionQueue(object): @defer.inlineCallbacks @log_function def _attempt_new_transaction(self, destination): - - (retry_last_ts, retry_interval) = (0, 0) - retry_timings = yield self.store.get_destination_retry_timings( - destination - ) - if retry_timings: - (retry_last_ts, retry_interval) = ( - retry_timings.retry_last_ts, retry_timings.retry_interval - ) - if retry_last_ts + retry_interval > int(self._clock.time_msec()): - logger.info( - "TX [%s] not ready for retry yet - " - "dropping transaction for now", - destination, - ) - return - else: - logger.info("TX [%s] is ready for retry", destination) - if destination in self.pending_transactions: # XXX: pending_transactions can get stuck on by a never-ending # request at which point pending_pdus_by_dest just keeps growing. @@ -192,15 +176,6 @@ class TransactionQueue(object): logger.info("TX [%s] Nothing to send", destination) return - logger.debug( - "TX [%s] Attempting new transaction" - " (pdus: %d, edus: %d, failures: %d)", - destination, - len(pending_pdus), - len(pending_edus), - len(pending_failures) - ) - # Sort based on the order field pending_pdus.sort(key=lambda t: t[2]) @@ -213,6 +188,21 @@ class TransactionQueue(object): ] try: + limiter = yield get_retry_limiter( + destination, + self._clock, + self.store, + ) + + logger.debug( + "TX [%s] Attempting new transaction" + " (pdus: %d, edus: %d, failures: %d)", + destination, + len(pending_pdus), + len(pending_edus), + len(pending_failures) + ) + self.pending_transactions[destination] = 1 logger.debug("TX [%s] Persisting transaction...", destination) @@ -238,61 +228,57 @@ class TransactionQueue(object): transaction.transaction_id, ) - # Actually send the transaction + with limiter: + # Actually send the transaction - # FIXME (erikj): This is a bit of a hack to make the Pdu age - # keys work - def json_data_cb(): - data = transaction.get_dict() - now = int(self._clock.time_msec()) - if "pdus" in data: - for p in data["pdus"]: - if "age_ts" in p: - unsigned = p.setdefault("unsigned", {}) - unsigned["age"] = now - int(p["age_ts"]) - del p["age_ts"] - return data + # FIXME (erikj): This is a bit of a hack to make the Pdu age + # keys work + def json_data_cb(): + data = transaction.get_dict() + now = int(self._clock.time_msec()) + if "pdus" in data: + for p in data["pdus"]: + if "age_ts" in p: + unsigned = p.setdefault("unsigned", {}) + unsigned["age"] = now - int(p["age_ts"]) + del p["age_ts"] + return data - try: - response = yield self.transport_layer.send_transaction( - transaction, json_data_cb - ) - code = 200 + try: + response = yield self.transport_layer.send_transaction( + transaction, json_data_cb + ) + code = 200 - if response: - for e_id, r in getattr(response, "pdus", {}).items(): - if "error" in r: - logger.warn( - "Transaction returned error for %s: %s", - e_id, r, - ) + if response: + for e_id, r in getattr(response, "pdus", {}).items(): + if "error" in r: + logger.warn( + "Transaction returned error for %s: %s", + e_id, r, + ) + except HttpResponseException as e: + code = e.code + response = e.response - except HttpResponseException as e: - code = e.code - response = e.response + logger.info("TX [%s] got %d response", destination, code) - logger.info("TX [%s] got %d response", destination, code) + logger.debug("TX [%s] Sent transaction", destination) + logger.debug("TX [%s] Marking as delivered...", destination) - logger.debug("TX [%s] Sent transaction", destination) - logger.debug("TX [%s] Marking as delivered...", destination) yield self.transaction_actions.delivered( transaction, code, response ) logger.debug("TX [%s] Marked as delivered", destination) + logger.debug("TX [%s] Yielding to callbacks...", destination) for deferred in deferreds: if code == 200: - if retry_last_ts: - # this host is alive! reset retry schedule - yield self.store.set_destination_retry_timings( - destination, 0, 0 - ) deferred.callback(None) else: - self.set_retrying(destination, retry_interval) deferred.errback(RuntimeError("Got status %d" % code)) # Ensures we don't continue until all callbacks on that @@ -303,6 +289,12 @@ class TransactionQueue(object): pass logger.debug("TX [%s] Yielded to callbacks", destination) + except NotRetryingDestination: + logger.info( + "TX [%s] not ready for retry yet - " + "dropping transaction for now", + destination, + ) except RuntimeError as e: # We capture this here as there as nothing actually listens # for this finishing functions deferred. @@ -320,8 +312,6 @@ class TransactionQueue(object): e, ) - self.set_retrying(destination, retry_interval) - for deferred in deferreds: if not deferred.called: deferred.errback(e) @@ -332,22 +322,3 @@ class TransactionQueue(object): # Check to see if there is anything else to send. self._attempt_new_transaction(destination) - - @defer.inlineCallbacks - def set_retrying(self, destination, retry_interval): - # track that this destination is having problems and we should - # give it a chance to recover before trying it again - - if retry_interval: - retry_interval *= 2 - # plateau at hourly retries for now - if retry_interval >= 60 * 60 * 1000: - retry_interval = 60 * 60 * 1000 - else: - retry_interval = 2000 # try again at first after 2 seconds - - yield self.store.set_destination_retry_timings( - destination, - int(self._clock.time_msec()), - retry_interval - ) diff --git a/synapse/util/retryutils.py b/synapse/util/retryutils.py new file mode 100644 index 000000000..366f7c48a --- /dev/null +++ b/synapse/util/retryutils.py @@ -0,0 +1,153 @@ +# -*- coding: utf-8 -*- +# Copyright 2015 OpenMarket Ltd +# +# 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 twisted.internet import defer + +from synapse.api.errors import CodeMessageException + +import logging + + +logger = logging.getLogger(__name__) + + +class NotRetryingDestination(Exception): + def __init__(self, retry_last_ts, retry_interval, destination): + msg = "Not retrying server %s." % (destination,) + super(NotRetryingDestination, self).__init__(msg) + + self.retry_last_ts = retry_last_ts + self.retry_interval = retry_interval + self.destination = destination + + +@defer.inlineCallbacks +def get_retry_limiter(destination, clock, store, **kwargs): + """For a given destination check if we have previously failed to + send a request there and are waiting before retrying the destination. + If we are not ready to retry the destination, this will raise a + NotRetryingDestination exception. Otherwise, will return a Context Manager + that will mark the destination as down if an exception is thrown (excluding + CodeMessageException with code < 500) + + Example usage: + + try: + limiter = yield get_retry_limiter(destination, clock, store) + with limiter: + response = yield do_request() + except NotRetryingDestination: + # We aren't ready to retry that destination. + raise + """ + retry_last_ts, retry_interval = (0, 0) + + retry_timings = yield store.get_destination_retry_timings( + destination + ) + + if retry_timings: + retry_last_ts, retry_interval = ( + retry_timings.retry_last_ts, retry_timings.retry_interval + ) + + now = int(clock.time_msec()) + + if retry_last_ts + retry_interval > now: + raise NotRetryingDestination( + retry_last_ts=retry_last_ts, + retry_interval=retry_interval, + destination=destination, + ) + + defer.returnValue( + RetryDestinationLimiter( + destination, + clock, + store, + retry_interval, + **kwargs + ) + ) + + +class RetryDestinationLimiter(object): + def __init__(self, destination, clock, store, retry_interval, + min_retry_interval=5000, max_retry_interval=60 * 60 * 1000, + multiplier_retry_interval=2,): + """Marks the destination as "down" if an exception is thrown in the + context, except for CodeMessageException with code < 500. + + If no exception is raised, marks the destination as "up". + + Args: + destination (str) + clock (Clock) + store (DataStore) + retry_interval (int): The next retry interval taken from the + database in milliseconds, or zero if the last request was + successful. + min_retry_interval (int): The minimum retry interval to use after + a failed request, in milliseconds. + max_retry_interval (int): The maximum retry interval to use after + a failed request, in milliseconds. + multiplier_retry_interval (int): The multiplier to use to increase + the retry interval after a failed request. + """ + self.clock = clock + self.store = store + self.destination = destination + + self.retry_interval = retry_interval + self.min_retry_interval = min_retry_interval + self.max_retry_interval = max_retry_interval + self.multiplier_retry_interval = multiplier_retry_interval + + def __enter__(self): + pass + + def __exit__(self, exc_type, exc_val, exc_tb): + def err(failure): + logger.exception( + "Failed to store set_destination_retry_timings", + failure.value + ) + + valid_err_code = False + if exc_type is CodeMessageException: + valid_err_code = 0 <= exc_val.code < 500 + + if exc_type is None or valid_err_code: + # We connected successfully. + if not self.retry_interval: + return + + retry_last_ts = 0 + self.retry_interval = 0 + else: + # We couldn't connect. + if self.retry_interval: + self.retry_interval *= self.multiplier_retry_interval + + if self.retry_interval >= self.max_retry_interval: + self.retry_interval = self.max_retry_interval + else: + self.retry_interval = self.min_retry_interval + + retry_last_ts = int(self._clock.time_msec()), + + self.store.set_destination_retry_timings( + self.destination, retry_last_ts, self.retry_interval + ).addErrback(err)