Thread through instance name to replication client. (#7369)

For in memory streams when fetching updates on workers we need to query the source of the stream, which currently is hard coded to be master. This PR threads through the source instance we received via `POSITION` through to the update function in each stream, which can then be passed to the replication client for in memory streams.

1 files changed, 15 insertions, 5 deletions

diff --git a/synapse/replication/tcp/handler.py b/synapse/replication/tcp/handler.py
index d72f3d0cf9..2d1d119c7c 100644
--- a/synapse/replication/tcp/handler.py
+++ b/synapse/replication/tcp/handler.py
@@ -278,19 +278,24 @@ class ReplicationCommandHandler:
                 # Check if this is the last of a batch of updates
                 rows = self._pending_batches.pop(stream_name, [])
                 rows.append(row)
-                await self.on_rdata(stream_name, cmd.token, rows)
+                await self.on_rdata(stream_name, cmd.instance_name, cmd.token, rows)
 
-    async def on_rdata(self, stream_name: str, token: int, rows: list):
+    async def on_rdata(
+        self, stream_name: str, instance_name: str, token: int, rows: list
+    ):
         """Called to handle a batch of replication data with a given stream token.
 
         Args:
             stream_name: name of the replication stream for this batch of rows
+            instance_name: the instance that wrote the rows.
             token: stream token for this batch of rows
             rows: a list of Stream.ROW_TYPE objects as returned by
                 Stream.parse_row.
         """
         logger.debug("Received rdata %s -> %s", stream_name, token)
-        await self._replication_data_handler.on_rdata(stream_name, token, rows)
+        await self._replication_data_handler.on_rdata(
+            stream_name, instance_name, token, rows
+        )
 
     async def on_POSITION(self, conn: AbstractConnection, cmd: PositionCommand):
         if cmd.instance_name == self._instance_name:
@@ -325,7 +330,9 @@ class ReplicationCommandHandler:
                     updates,
                     current_token,
                     missing_updates,
-                ) = await stream.get_updates_since(current_token, cmd.token)
+                ) = await stream.get_updates_since(
+                    cmd.instance_name, current_token, cmd.token
+                )
 
                 # TODO: add some tests for this
 
@@ -334,7 +341,10 @@ class ReplicationCommandHandler:
 
                 for token, rows in _batch_updates(updates):
                     await self.on_rdata(
-                        cmd.stream_name, token, [stream.parse_row(row) for row in rows],
+                        cmd.stream_name,
+                        cmd.instance_name,
+                        token,
+                        [stream.parse_row(row) for row in rows],
                     )
 
             # We've now caught up to position sent to us, notify handler.