diff options
Diffstat (limited to 'synapse/replication/tcp/client.py')
| -rw-r--r-- | synapse/replication/tcp/client.py | 196 |
1 files changed, 196 insertions, 0 deletions
diff --git a/synapse/replication/tcp/client.py b/synapse/replication/tcp/client.py new file mode 100644 index 0000000000..90fb6c1336 --- /dev/null +++ b/synapse/replication/tcp/client.py @@ -0,0 +1,196 @@ +# -*- coding: utf-8 -*- +# Copyright 2017 Vector Creations 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. +"""A replication client for use by synapse workers. +""" + +from twisted.internet import reactor, defer +from twisted.internet.protocol import ReconnectingClientFactory + +from .commands import ( + FederationAckCommand, UserSyncCommand, RemovePusherCommand, InvalidateCacheCommand, +) +from .protocol import ClientReplicationStreamProtocol + +import logging + +logger = logging.getLogger(__name__) + + +class ReplicationClientFactory(ReconnectingClientFactory): + """Factory for building connections to the master. Will reconnect if the + connection is lost. + + Accepts a handler that will be called when new data is available or data + is required. + """ + maxDelay = 5 # Try at least once every N seconds + + def __init__(self, hs, client_name, handler): + self.client_name = client_name + self.handler = handler + self.server_name = hs.config.server_name + self._clock = hs.get_clock() # As self.clock is defined in super class + + reactor.addSystemEventTrigger("before", "shutdown", self.stopTrying) + + def startedConnecting(self, connector): + logger.info("Connecting to replication: %r", connector.getDestination()) + + def buildProtocol(self, addr): + logger.info("Connected to replication: %r", addr) + self.resetDelay() + return ClientReplicationStreamProtocol( + self.client_name, self.server_name, self._clock, self.handler + ) + + def clientConnectionLost(self, connector, reason): + logger.error("Lost replication conn: %r", reason) + ReconnectingClientFactory.clientConnectionLost(self, connector, reason) + + def clientConnectionFailed(self, connector, reason): + logger.error("Failed to connect to replication: %r", reason) + ReconnectingClientFactory.clientConnectionFailed( + self, connector, reason + ) + + +class ReplicationClientHandler(object): + """A base handler that can be passed to the ReplicationClientFactory. + + By default proxies incoming replication data to the SlaveStore. + """ + def __init__(self, store): + self.store = store + + # The current connection. None if we are currently (re)connecting + self.connection = None + + # Any pending commands to be sent once a new connection has been + # established + self.pending_commands = [] + + # Map from string -> deferred, to wake up when receiveing a SYNC with + # the given string. + # Used for tests. + self.awaiting_syncs = {} + + def start_replication(self, hs): + """Helper method to start a replication connection to the remote server + using TCP. + """ + client_name = hs.config.worker_name + factory = ReplicationClientFactory(hs, client_name, self) + host = hs.config.worker_replication_host + port = hs.config.worker_replication_port + reactor.connectTCP(host, port, factory) + + def on_rdata(self, stream_name, token, rows): + """Called when we get new replication data. By default this just pokes + the slave store. + + Can be overriden in subclasses to handle more. + """ + logger.info("Received rdata %s -> %s", stream_name, token) + self.store.process_replication_rows(stream_name, token, rows) + + def on_position(self, stream_name, token): + """Called when we get new position data. By default this just pokes + the slave store. + + Can be overriden in subclasses to handle more. + """ + self.store.process_replication_rows(stream_name, token, []) + + def on_sync(self, data): + """When we received a SYNC we wake up any deferreds that were waiting + for the sync with the given data. + + Used by tests. + """ + d = self.awaiting_syncs.pop(data, None) + if d: + d.callback(data) + + def get_streams_to_replicate(self): + """Called when a new connection has been established and we need to + subscribe to streams. + + Returns a dictionary of stream name to token. + """ + args = self.store.stream_positions() + user_account_data = args.pop("user_account_data", None) + room_account_data = args.pop("room_account_data", None) + if user_account_data: + args["account_data"] = user_account_data + elif room_account_data: + args["account_data"] = room_account_data + return args + + def get_currently_syncing_users(self): + """Get the list of currently syncing users (if any). This is called + when a connection has been established and we need to send the + currently syncing users. (Overriden by the synchrotron's only) + """ + return [] + + def send_command(self, cmd): + """Send a command to master (when we get establish a connection if we + don't have one already.) + """ + if self.connection: + self.connection.send_command(cmd) + else: + logger.warn("Queuing command as not connected: %r", cmd.NAME) + self.pending_commands.append(cmd) + + def send_federation_ack(self, token): + """Ack data for the federation stream. This allows the master to drop + data stored purely in memory. + """ + self.send_command(FederationAckCommand(token)) + + def send_user_sync(self, user_id, is_syncing, last_sync_ms): + """Poke the master that a user has started/stopped syncing. + """ + self.send_command(UserSyncCommand(user_id, is_syncing, last_sync_ms)) + + def send_remove_pusher(self, app_id, push_key, user_id): + """Poke the master to remove a pusher for a user + """ + cmd = RemovePusherCommand(app_id, push_key, user_id) + self.send_command(cmd) + + def send_invalidate_cache(self, cache_func, keys): + """Poke the master to invalidate a cache. + """ + cmd = InvalidateCacheCommand(cache_func.__name__, keys) + self.send_command(cmd) + + def await_sync(self, data): + """Returns a deferred that is resolved when we receive a SYNC command + with given data. + + Used by tests. + """ + return self.awaiting_syncs.setdefault(data, defer.Deferred()) + + def update_connection(self, connection): + """Called when a connection has been established (or lost with None). + """ + self.connection = connection + if connection: + for cmd in self.pending_commands: + connection.send_command(cmd) + self.pending_commands = [] |