WIP: Completely change how event streaming and pagination work. This reflects the change in the underlying storage model.

synapse/handlers/events.py

@@ -16,19 +16,15 @@
 from twisted.internet import defer
 
 from ._base import BaseHandler
-from synapse.api.streams.event import (
-    EventStream, EventsStreamData
-)
-from synapse.handlers.presence import PresenceStreamData
+
+import logging
+
+
+logger = logging.getLogger(__name__)
 
 
 class EventStreamHandler(BaseHandler):
 
-    stream_data_classes = [
-        EventsStreamData,
-        PresenceStreamData,
-    ]
-
     def __init__(self, hs):
         super(EventStreamHandler, self).__init__(hs)
 
@@ -43,104 +39,22 @@ class EventStreamHandler(BaseHandler):
 
         self.clock = hs.get_clock()
 
-    def get_event_stream_token(self, stream_type, store_id, start_token):
-        """Return the next token after this event.
-
-        Args:
-            stream_type (str): The StreamData.EVENT_TYPE
-            store_id (int): The new storage ID assigned from the data store.
-            start_token (str): The token the user started with.
-        Returns:
-            str: The end token.
-        """
-        for i, stream_cls in enumerate(EventStreamHandler.stream_data_classes):
-            if stream_cls.EVENT_TYPE == stream_type:
-                # this is the stream for this event, so replace this part of
-                # the token
-                store_ids = start_token.split(EventStream.SEPARATOR)
-                store_ids[i] = str(store_id)
-                return EventStream.SEPARATOR.join(store_ids)
-        raise RuntimeError("Didn't find a stream type %s" % stream_type)
+        self.notifier = hs.get_notifier()
 
     @defer.inlineCallbacks
     def get_stream(self, auth_user_id, pagin_config, timeout=0):
-        """Gets events as an event stream for this user.
-
-        This function looks for interesting *events* for this user. This is
-        different from the notifier, which looks for interested *users* who may
-        want to know about a single event.
-
-        Args:
-            auth_user_id (str): The user requesting their event stream.
-            pagin_config (synapse.api.streams.PaginationConfig): The config to
-            use when obtaining the stream.
-            timeout (int): The max time to wait for an incoming event in ms.
-        Returns:
-            A pagination stream API dict
-        """
         auth_user = self.hs.parse_userid(auth_user_id)
 
-        stream_id = object()
+        if pagin_config.from_token is None:
+            pagin_config.from_token = None
 
-        try:
-            if auth_user not in self._streams_per_user:
-                self._streams_per_user[auth_user] = 0
-                if auth_user in self._stop_timer_per_user:
-                    self.clock.cancel_call_later(
-                        self._stop_timer_per_user.pop(auth_user))
-                else:
-                    self.distributor.fire(
-                        "started_user_eventstream", auth_user
-                    )
-            self._streams_per_user[auth_user] += 1
+        events, tokens = yield self.notifier.get_events_for(auth_user, pagin_config, timeout)
 
-            # construct an event stream with the correct data ordering
-            stream_data_list = []
-            for stream_class in EventStreamHandler.stream_data_classes:
-                stream_data_list.append(stream_class(self.hs))
-            event_stream = EventStream(auth_user_id, stream_data_list)
+        chunk = {
+            "chunk": [e.get_dict() for e in events],
+            "start_token": tokens[0].to_string(),
+            "end_token": tokens[1].to_string(),
+        }
 
-            # fix unknown tokens to known tokens
-            pagin_config = yield event_stream.fix_tokens(pagin_config)
+        defer.returnValue(chunk)
 
-            # register interest in receiving new events
-            self.notifier.store_events_for(user_id=auth_user_id,
-                                           stream_id=stream_id,
-                                           from_tok=pagin_config.from_tok)
-
-            # see if we can grab a chunk now
-            data_chunk = yield event_stream.get_chunk(config=pagin_config)
-
-            # if there are previous events, return those. If not, wait on the
-            # new events for 'timeout' seconds.
-            if len(data_chunk["chunk"]) == 0 and timeout != 0:
-                results = yield defer.maybeDeferred(
-                    self.notifier.get_events_for,
-                    user_id=auth_user_id,
-                    stream_id=stream_id,
-                    timeout=timeout
-                )
-                if results:
-                    defer.returnValue(results)
-
-            defer.returnValue(data_chunk)
-        finally:
-            # cleanup
-            self.notifier.purge_events_for(user_id=auth_user_id,
-                                           stream_id=stream_id)
-
-            self._streams_per_user[auth_user] -= 1
-            if not self._streams_per_user[auth_user]:
-                del self._streams_per_user[auth_user]
-
-                # 10 seconds of grace to allow the client to reconnect again
-                #   before we think they're gone
-                def _later():
-                    self.distributor.fire(
-                        "stopped_user_eventstream", auth_user
-                    )
-                    del self._stop_timer_per_user[auth_user]
-
-                self._stop_timer_per_user[auth_user] = (
-                    self.clock.call_later(5, _later)
-                )