Matrix-Mirrors/anonymousland-synapse
1
0
Fork 0
mirror of https://git.anonymousland.org/anonymousland/synapse.git synced 2024-10-01 11:49:51 -04:00
Code Issues Packages Projects Releases Wiki Activity

Wait to subscribe before sending REPLICATE

Browse Source
This commit is contained in:
Richard van der Hoff 2020-05-05 18:53:38 +01:00
parent b2dba06079
commit d78265af0c
2 changed files with 35 additions and 20 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

3
synapse/replication/tcp/handler.py
View File

@ -99,7 +99,8 @@ class ReplicationCommandHandler:
# The factory used to create connections. # The factory used to create connections.
self._factory = None # type: Optional[ReconnectingClientFactory] self._factory = None # type: Optional[ReconnectingClientFactory]
# The currently connected connections. # The currently connected connections. (The list of places we need to send
# outgoing replication commands to.)
self._connections = [] # type: List[AbstractConnection] self._connections = [] # type: List[AbstractConnection]
LaterGauge( LaterGauge(

52
synapse/replication/tcp/redis.py
View File

@ -18,7 +18,7 @@ from typing import TYPE_CHECKING
import txredisapi import txredisapi
from synapse.logging.context import PreserveLoggingContext from synapse.logging.context import make_deferred_yieldable
from synapse.metrics.background_process_metrics import run_as_background_process from synapse.metrics.background_process_metrics import run_as_background_process
from synapse.replication.tcp.commands import ( from synapse.replication.tcp.commands import (
Command, Command,
@ -41,8 +41,14 @@ logger = logging.getLogger(__name__)
class RedisSubscriber(txredisapi.SubscriberProtocol, AbstractConnection): class RedisSubscriber(txredisapi.SubscriberProtocol, AbstractConnection):
"""Connection to redis subscribed to replication stream. """Connection to redis subscribed to replication stream.
Parses incoming messages from redis into replication commands, and passes This class fulfils two functions:
them to `ReplicationCommandHandler`
(a) it implements the twisted Protocol API, where it handles the SUBSCRIBEd redis
connection, parsing *incoming* messages into replication commands, and passing them
to `ReplicationCommandHandler`
(b) it implements the AbstractConnection API, where it sends *outgoing* commands
onto outbound_redis_connection.
Due to the vagaries of `txredisapi` we don't want to have a custom Due to the vagaries of `txredisapi` we don't want to have a custom
constructor, so instead we expect the defined attributes below to be set constructor, so instead we expect the defined attributes below to be set
@ -50,8 +56,8 @@ class RedisSubscriber(txredisapi.SubscriberProtocol, AbstractConnection):
Attributes: Attributes:
handler: The command handler to handle incoming commands. handler: The command handler to handle incoming commands.
stream_name: The *redis* stream name to subscribe to (not anything to stream_name: The *redis* stream name to subscribe to and publish from
do with Synapse replication streams). (not anything to do with Synapse replication streams).
outbound_redis_connection: The connection to redis to use to send outbound_redis_connection: The connection to redis to use to send
commands. commands.
""" """
@ -61,12 +67,22 @@ class RedisSubscriber(txredisapi.SubscriberProtocol, AbstractConnection):
outbound_redis_connection = None # type: txredisapi.RedisProtocol outbound_redis_connection = None # type: txredisapi.RedisProtocol
def connectionMade(self): def connectionMade(self):
logger.info("Connected to redis instance") logger.info("Connected to redis")
self.subscribe(self.stream_name) run_as_background_process("subscribe-replication", self._send_subscribe)
self.send_command(ReplicateCommand())
self.handler.new_connection(self) self.handler.new_connection(self)
async def _send_subscribe(self):
# it's important to make sure that we only send the REPLICATE command once we
# have successfully subscribed to the stream - otherwise we might miss the
# POSITION response sent back by the other end.
logger.info("Sending redis SUBSCRIBE for %s", self.stream_name)
await make_deferred_yieldable(self.subscribe(self.stream_name))
logger.info(
"Successfully subscribed to redis stream, sending REPLICATE command"
)
await self._async_send_command(ReplicateCommand())
logger.info("REPLICATE successfully sent")
def messageReceived(self, pattern: str, channel: str, message: str): def messageReceived(self, pattern: str, channel: str, message: str):
"""Received a message from redis. """Received a message from redis.
""" """
@ -119,7 +135,7 @@ class RedisSubscriber(txredisapi.SubscriberProtocol, AbstractConnection):
logger.warning("Unhandled command: %r", cmd) logger.warning("Unhandled command: %r", cmd)
def connectionLost(self, reason): def connectionLost(self, reason):
logger.info("Lost connection to redis instance") logger.info("Lost connection to redis")
self.handler.lost_connection(self) self.handler.lost_connection(self)
def send_command(self, cmd: Command): def send_command(self, cmd: Command):
@ -128,6 +144,10 @@ class RedisSubscriber(txredisapi.SubscriberProtocol, AbstractConnection):
Args: Args:
cmd (Command) cmd (Command)
""" """
run_as_background_process("send-cmd", self._send_command, cmd)
async def _async_send_command(self, cmd: Command):
"""Encode a replication command and send it over our outbound connection"""
string = "%s %s" % (cmd.NAME, cmd.to_line()) string = "%s %s" % (cmd.NAME, cmd.to_line())
if "\n" in string: if "\n" in string:
raise Exception("Unexpected newline in command: %r", string) raise Exception("Unexpected newline in command: %r", string)
@ -138,15 +158,9 @@ class RedisSubscriber(txredisapi.SubscriberProtocol, AbstractConnection):
# remote instances. # remote instances.
tcp_outbound_commands_counter.labels(cmd.NAME, "redis").inc() tcp_outbound_commands_counter.labels(cmd.NAME, "redis").inc()
async def _send(): await make_deferred_yieldable(
with PreserveLoggingContext(): self.outbound_redis_connection.publish(self.stream_name, encoded_string)
# Note that we use the other connection as we can't send )
# commands using the subscription connection.
await self.outbound_redis_connection.publish(
self.stream_name, encoded_string
)
run_as_background_process("send-cmd", _send)
class RedisDirectTcpReplicationClientFactory(txredisapi.SubscriberFactory): class RedisDirectTcpReplicationClientFactory(txredisapi.SubscriberFactory):