Merge pull request #3709 from matrix-org/rav/logcontext_for_replication_commands

Logcontexts for replication command handlers

9 files changed, 54 insertions, 20 deletions

diff --git a/changelog.d/3709.misc b/changelog.d/3709.misc
new file mode 100644
index 0000000000..bbda357d44
--- /dev/null
+++ b/changelog.d/3709.misc
@@ -0,0 +1 @@
+Logcontexts for replication command handlers
diff --git a/synapse/app/appservice.py b/synapse/app/appservice.py
index 9a37384fb7..3348a8ec6d 100644
--- a/synapse/app/appservice.py
+++ b/synapse/app/appservice.py
@@ -117,8 +117,9 @@ class ASReplicationHandler(ReplicationClientHandler):
         super(ASReplicationHandler, self).__init__(hs.get_datastore())
         self.appservice_handler = hs.get_application_service_handler()
 
+    @defer.inlineCallbacks
     def on_rdata(self, stream_name, token, rows):
-        super(ASReplicationHandler, self).on_rdata(stream_name, token, rows)
+        yield super(ASReplicationHandler, self).on_rdata(stream_name, token, rows)
 
         if stream_name == "events":
             max_stream_id = self.store.get_room_max_stream_ordering()
diff --git a/synapse/app/federation_sender.py b/synapse/app/federation_sender.py
index 7a4310ca18..d59007099b 100644
--- a/synapse/app/federation_sender.py
+++ b/synapse/app/federation_sender.py
@@ -144,8 +144,9 @@ class FederationSenderReplicationHandler(ReplicationClientHandler):
         super(FederationSenderReplicationHandler, self).__init__(hs.get_datastore())
         self.send_handler = FederationSenderHandler(hs, self)
 
+    @defer.inlineCallbacks
     def on_rdata(self, stream_name, token, rows):
-        super(FederationSenderReplicationHandler, self).on_rdata(
+        yield super(FederationSenderReplicationHandler, self).on_rdata(
             stream_name, token, rows
         )
         self.send_handler.process_replication_rows(stream_name, token, rows)
diff --git a/synapse/app/pusher.py b/synapse/app/pusher.py
index 0089a7c64f..a4fc7e91fa 100644
--- a/synapse/app/pusher.py
+++ b/synapse/app/pusher.py
@@ -148,8 +148,9 @@ class PusherReplicationHandler(ReplicationClientHandler):
 
         self.pusher_pool = hs.get_pusherpool()
 
+    @defer.inlineCallbacks
     def on_rdata(self, stream_name, token, rows):
-        super(PusherReplicationHandler, self).on_rdata(stream_name, token, rows)
+        yield super(PusherReplicationHandler, self).on_rdata(stream_name, token, rows)
         run_in_background(self.poke_pushers, stream_name, token, rows)
 
     @defer.inlineCallbacks
diff --git a/synapse/app/synchrotron.py b/synapse/app/synchrotron.py
index cade09d60e..27e1998660 100644
--- a/synapse/app/synchrotron.py
+++ b/synapse/app/synchrotron.py
@@ -338,8 +338,9 @@ class SyncReplicationHandler(ReplicationClientHandler):
         self.presence_handler = hs.get_presence_handler()
         self.notifier = hs.get_notifier()
 
+    @defer.inlineCallbacks
     def on_rdata(self, stream_name, token, rows):
-        super(SyncReplicationHandler, self).on_rdata(stream_name, token, rows)
+        yield super(SyncReplicationHandler, self).on_rdata(stream_name, token, rows)
         run_in_background(self.process_and_notify, stream_name, token, rows)
 
     def get_streams_to_replicate(self):
diff --git a/synapse/app/user_dir.py b/synapse/app/user_dir.py
index cb78de8834..1388a42b59 100644
--- a/synapse/app/user_dir.py
+++ b/synapse/app/user_dir.py
@@ -169,8 +169,9 @@ class UserDirectoryReplicationHandler(ReplicationClientHandler):
         super(UserDirectoryReplicationHandler, self).__init__(hs.get_datastore())
         self.user_directory = hs.get_user_directory_handler()
 
+    @defer.inlineCallbacks
     def on_rdata(self, stream_name, token, rows):
-        super(UserDirectoryReplicationHandler, self).on_rdata(
+        yield super(UserDirectoryReplicationHandler, self).on_rdata(
             stream_name, token, rows
         )
         if stream_name == "current_state_deltas":
diff --git a/synapse/replication/tcp/client.py b/synapse/replication/tcp/client.py
index 970e94313e..cbe9645817 100644
--- a/synapse/replication/tcp/client.py
+++ b/synapse/replication/tcp/client.py
@@ -107,7 +107,7 @@ class ReplicationClientHandler(object):
         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)
+        return 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
@@ -115,7 +115,7 @@ class ReplicationClientHandler(object):
 
         Can be overriden in subclasses to handle more.
         """
-        self.store.process_replication_rows(stream_name, token, [])
+        return 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
diff --git a/synapse/replication/tcp/commands.py b/synapse/replication/tcp/commands.py
index f3908df642..327556f6a1 100644
--- a/synapse/replication/tcp/commands.py
+++ b/synapse/replication/tcp/commands.py
@@ -59,6 +59,12 @@ class Command(object):
         """
         return self.data
 
+    def get_logcontext_id(self):
+        """Get a suitable string for the logcontext when processing this command"""
+
+        # by default, we just use the command name.
+        return self.NAME
+
 
 class ServerCommand(Command):
     """Sent by the server on new connection and includes the server_name.
@@ -116,6 +122,9 @@ class RdataCommand(Command):
             _json_encoder.encode(self.row),
         ))
 
+    def get_logcontext_id(self):
+        return "RDATA-" + self.stream_name
+
 
 class PositionCommand(Command):
     """Sent by the client to tell the client the stream postition without
@@ -190,6 +199,9 @@ class ReplicateCommand(Command):
     def to_line(self):
         return " ".join((self.stream_name, str(self.token),))
 
+    def get_logcontext_id(self):
+        return "REPLICATE-" + self.stream_name
+
 
 class UserSyncCommand(Command):
     """Sent by the client to inform the server that a user has started or
diff --git a/synapse/replication/tcp/protocol.py b/synapse/replication/tcp/protocol.py
index dec5ac0913..74e892c104 100644
--- a/synapse/replication/tcp/protocol.py
+++ b/synapse/replication/tcp/protocol.py
@@ -63,6 +63,8 @@ from twisted.protocols.basic import LineOnlyReceiver
 from twisted.python.failure import Failure
 
 from synapse.metrics import LaterGauge
+from synapse.metrics.background_process_metrics import run_as_background_process
+from synapse.util.logcontext import make_deferred_yieldable, run_in_background
 from synapse.util.stringutils import random_string
 
 from .commands import (
@@ -222,7 +224,11 @@ class BaseReplicationStreamProtocol(LineOnlyReceiver):
 
         # Now lets try and call on_<CMD_NAME> function
         try:
-            getattr(self, "on_%s" % (cmd_name,))(cmd)
+            run_as_background_process(
+                "replication-" + cmd.get_logcontext_id(),
+                getattr(self, "on_%s" % (cmd_name,)),
+                cmd,
+            )
         except Exception:
             logger.exception("[%s] Failed to handle line: %r", self.id(), line)
 
@@ -387,7 +393,7 @@ class ServerReplicationStreamProtocol(BaseReplicationStreamProtocol):
         self.name = cmd.data
 
     def on_USER_SYNC(self, cmd):
-        self.streamer.on_user_sync(
+        return self.streamer.on_user_sync(
             self.conn_id, cmd.user_id, cmd.is_syncing, cmd.last_sync_ms,
         )
 
@@ -397,22 +403,33 @@ class ServerReplicationStreamProtocol(BaseReplicationStreamProtocol):
 
         if stream_name == "ALL":
             # Subscribe to all streams we're publishing to.
-            for stream in iterkeys(self.streamer.streams_by_name):
-                self.subscribe_to_stream(stream, token)
+            deferreds = [
+                run_in_background(
+                    self.subscribe_to_stream,
+                    stream, token,
+                )
+                for stream in iterkeys(self.streamer.streams_by_name)
+            ]
+
+            return make_deferred_yieldable(
+                defer.gatherResults(deferreds, consumeErrors=True)
+            )
         else:
-            self.subscribe_to_stream(stream_name, token)
+            return self.subscribe_to_stream(stream_name, token)
 
     def on_FEDERATION_ACK(self, cmd):
-        self.streamer.federation_ack(cmd.token)
+        return self.streamer.federation_ack(cmd.token)
 
     def on_REMOVE_PUSHER(self, cmd):
-        self.streamer.on_remove_pusher(cmd.app_id, cmd.push_key, cmd.user_id)
+        return self.streamer.on_remove_pusher(
+            cmd.app_id, cmd.push_key, cmd.user_id,
+        )
 
     def on_INVALIDATE_CACHE(self, cmd):
-        self.streamer.on_invalidate_cache(cmd.cache_func, cmd.keys)
+        return self.streamer.on_invalidate_cache(cmd.cache_func, cmd.keys)
 
     def on_USER_IP(self, cmd):
-        self.streamer.on_user_ip(
+        return self.streamer.on_user_ip(
             cmd.user_id, cmd.access_token, cmd.ip, cmd.user_agent, cmd.device_id,
             cmd.last_seen,
         )
@@ -542,14 +559,13 @@ class ClientReplicationStreamProtocol(BaseReplicationStreamProtocol):
             # Check if this is the last of a batch of updates
             rows = self.pending_batches.pop(stream_name, [])
             rows.append(row)
-
-            self.handler.on_rdata(stream_name, cmd.token, rows)
+            return self.handler.on_rdata(stream_name, cmd.token, rows)
 
     def on_POSITION(self, cmd):
-        self.handler.on_position(cmd.stream_name, cmd.token)
+        return self.handler.on_position(cmd.stream_name, cmd.token)
 
     def on_SYNC(self, cmd):
-        self.handler.on_sync(cmd.data)
+        return self.handler.on_sync(cmd.data)
 
     def replicate(self, stream_name, token):
         """Send the subscription request to the server