diff --git a/synapse/replication/tcp/protocol.py b/synapse/replication/tcp/protocol.py
index 429471c345..55630ba9a7 100644
--- a/synapse/replication/tcp/protocol.py
+++ b/synapse/replication/tcp/protocol.py
@@ -451,7 +451,7 @@ class ServerReplicationStreamProtocol(BaseReplicationStreamProtocol):
@defer.inlineCallbacks
def subscribe_to_stream(self, stream_name, token):
- """Subscribe the remote to a streams.
+ """Subscribe the remote to a stream.
This invloves checking if they've missed anything and sending those
updates down if they have. During that time new updates for the stream
@@ -478,11 +478,36 @@ class ServerReplicationStreamProtocol(BaseReplicationStreamProtocol):
# Now we can send any updates that came in while we were subscribing
pending_rdata = self.pending_rdata.pop(stream_name, [])
+ updates = []
for token, update in pending_rdata:
- # Only send updates newer than the current token
- if token > current_token:
+ # If the token is null, it is part of a batch update. Batches
+ # are multiple updates that share a single token. To denote
+ # this, the token is set to None for all tokens in the batch
+ # except for the last. If we find a None token, we keep looking
+ # through tokens until we find one that is not None and then
+ # process all previous updates in the batch as if they had the
+ # final token.
+ if token is None:
+ # Store this update as part of a batch
+ updates.append(update)
+ continue
+
+ if token <= current_token:
+ # This update or batch of updates is older than
+ # current_token, dismiss it
+ updates = []
+ continue
+
+ updates.append(update)
+
+ # Send all updates that are part of this batch with the
+ # found token
+ for update in updates:
self.send_command(RdataCommand(stream_name, token, update))
+ # Clear stored updates
+ updates = []
+
# They're now fully subscribed
self.replication_streams.add(stream_name)
except Exception as e:
@@ -526,6 +551,11 @@ class ClientReplicationStreamProtocol(BaseReplicationStreamProtocol):
self.server_name = server_name
self.handler = handler
+ # Set of stream names that have been subscribe to, but haven't yet
+ # caught up with. This is used to track when the client has been fully
+ # connected to the remote.
+ self.streams_connecting = set()
+
# Map of stream to batched updates. See RdataCommand for info on how
# batching works.
self.pending_batches = {}
@@ -548,6 +578,10 @@ class ClientReplicationStreamProtocol(BaseReplicationStreamProtocol):
# We've now finished connecting to so inform the client handler
self.handler.update_connection(self)
+ # This will happen if we don't actually subscribe to any streams
+ if not self.streams_connecting:
+ self.handler.finished_connecting()
+
def on_SERVER(self, cmd):
if cmd.data != self.server_name:
logger.error("[%s] Connected to wrong remote: %r", self.id(), cmd.data)
@@ -577,6 +611,12 @@ class ClientReplicationStreamProtocol(BaseReplicationStreamProtocol):
return self.handler.on_rdata(stream_name, cmd.token, rows)
def on_POSITION(self, cmd):
+ # When we get a `POSITION` command it means we've finished getting
+ # missing updates for the given stream, and are now up to date.
+ self.streams_connecting.discard(cmd.stream_name)
+ if not self.streams_connecting:
+ self.handler.finished_connecting()
+
return self.handler.on_position(cmd.stream_name, cmd.token)
def on_SYNC(self, cmd):
@@ -593,6 +633,8 @@ class ClientReplicationStreamProtocol(BaseReplicationStreamProtocol):
self.id(), stream_name, token
)
+ self.streams_connecting.add(stream_name)
+
self.send_command(ReplicateCommand(stream_name, token))
def on_connection_closed(self):
|
