Update some comments

Add a couple of type annotations, docstrings, and other comments, in the
interest of keeping track of what types I have.

Merged from pull request #370.

4 files changed, 98 insertions, 14 deletions

diff --git a/synapse/handlers/_base.py b/synapse/handlers/_base.py
index f4ade1f594..6519f183df 100644
--- a/synapse/handlers/_base.py
+++ b/synapse/handlers/_base.py
@@ -29,6 +29,12 @@ logger = logging.getLogger(__name__)
 
 
 class BaseHandler(object):
+    """
+    Common base class for the event handlers.
+
+    :type store: synapse.storage.events.StateStore
+    :type state_handler: synapse.state.StateHandler
+    """
 
     def __init__(self, hs):
         self.store = hs.get_datastore()
diff --git a/synapse/handlers/sync.py b/synapse/handlers/sync.py
index 492c1c17d5..ed93e5a2df 100644
--- a/synapse/handlers/sync.py
+++ b/synapse/handlers/sync.py
@@ -47,9 +47,9 @@ class TimelineBatch(collections.namedtuple("TimelineBatch", [
 
 
 class JoinedSyncResult(collections.namedtuple("JoinedSyncResult", [
-    "room_id",
-    "timeline",
-    "state",
+    "room_id",           # str
+    "timeline",          # TimelineBatch
+    "state",             # list[FrozenEvent]
     "ephemeral",
     "private_user_data",
 ])):
@@ -68,9 +68,9 @@ class JoinedSyncResult(collections.namedtuple("JoinedSyncResult", [
 
 
 class ArchivedSyncResult(collections.namedtuple("JoinedSyncResult", [
-    "room_id",
-    "timeline",
-    "state",
+    "room_id",            # str
+    "timeline",           # TimelineBatch
+    "state",              # list[FrozenEvent]
     "private_user_data",
 ])):
     __slots__ = []
@@ -87,8 +87,8 @@ class ArchivedSyncResult(collections.namedtuple("JoinedSyncResult", [
 
 
 class InvitedSyncResult(collections.namedtuple("InvitedSyncResult", [
-    "room_id",
-    "invite",
+    "room_id",   # str
+    "invite",    # FrozenEvent: the invite event
 ])):
     __slots__ = []
 
@@ -507,6 +507,9 @@ class SyncHandler(BaseHandler):
     @defer.inlineCallbacks
     def load_filtered_recents(self, room_id, sync_config, now_token,
                               since_token=None):
+        """
+        :returns a Deferred TimelineBatch
+        """
         limited = True
         recents = []
         filtering_factor = 2
@@ -680,8 +683,13 @@ class SyncHandler(BaseHandler):
     def compute_state_delta(self, since_token, previous_state, current_state):
         """ Works out the differnce in state between the current state and the
         state the client got when it last performed a sync.
-        Returns:
-            A list of events.
+
+        :param str since_token: the point we are comparing against
+        :param list[synapse.events.FrozenEvent] previous_state: the state to
+            compare to
+        :param list[synapse.events.FrozenEvent] current_state: the new state
+
+        :returns: A list of events.
         """
         # TODO(mjark) Check if the state events were received by the server
         # after the previous sync, since we need to include those state
@@ -696,6 +704,12 @@ class SyncHandler(BaseHandler):
 
     @defer.inlineCallbacks
     def check_joined_room(self, sync_config, room_id, state_delta):
+        """
+        Check if the user has just joined the given room. If so, return the
+        full state for the room, instead of the delta since the last sync.
+
+        :returns A deferred Tuple (state_delta, limited)
+        """
         joined = False
         limited = False
         for event in state_delta:
diff --git a/synapse/rest/client/v2_alpha/sync.py b/synapse/rest/client/v2_alpha/sync.py
index d24507effa..997a61abbb 100644
--- a/synapse/rest/client/v2_alpha/sync.py
+++ b/synapse/rest/client/v2_alpha/sync.py
@@ -165,6 +165,20 @@ class SyncRestServlet(RestServlet):
         return {"events": filter.filter_presence(formatted)}
 
     def encode_joined(self, rooms, filter, time_now, token_id):
+        """
+        Encode the joined rooms in a sync result
+
+        :param list[synapse.handlers.sync.JoinedSyncResult] rooms: list of sync
+            results for rooms this user is joined to
+        :param FilterCollection filter: filters to apply to the results
+        :param int time_now: current time - used as a baseline for age
+            calculations
+        :param int token_id: ID of the user's auth token - used for namespacing
+            of transaction IDs
+
+        :return: the joined rooms list, in our response format
+        :rtype: dict[str, dict[str, object]]
+        """
         joined = {}
         for room in rooms:
             joined[room.room_id] = self.encode_room(
@@ -174,6 +188,20 @@ class SyncRestServlet(RestServlet):
         return joined
 
     def encode_invited(self, rooms, filter, time_now, token_id):
+        """
+        Encode the invited rooms in a sync result
+
+        :param list[synapse.handlers.sync.InvitedSyncResult] rooms: list of
+             sync results for rooms this user is joined to
+        :param FilterCollection filter: filters to apply to the results
+        :param int time_now: current time - used as a baseline for age
+            calculations
+        :param int token_id: ID of the user's auth token - used for namespacing
+            of transaction IDs
+
+        :return: the invited rooms list, in our response format
+        :rtype: dict[str, dict[str, object]]
+        """
         invited = {}
         for room in rooms:
             invite = serialize_event(
@@ -189,6 +217,20 @@ class SyncRestServlet(RestServlet):
         return invited
 
     def encode_archived(self, rooms, filter, time_now, token_id):
+        """
+        Encode the archived rooms in a sync result
+
+        :param list[synapse.handlers.sync.ArchivedSyncResult] rooms: list of
+             sync results for rooms this user is joined to
+        :param FilterCollection filter: filters to apply to the results
+        :param int time_now: current time - used as a baseline for age
+            calculations
+        :param int token_id: ID of the user's auth token - used for namespacing
+            of transaction IDs
+
+        :return: the invited rooms list, in our response format
+        :rtype: dict[str, dict[str, object]]
+        """
         joined = {}
         for room in rooms:
             joined[room.room_id] = self.encode_room(
@@ -199,6 +241,20 @@ class SyncRestServlet(RestServlet):
 
     @staticmethod
     def encode_room(room, filter, time_now, token_id, joined=True):
+        """
+        :param JoinedSyncResult|ArchivedSyncResult room: sync result for a
+            single room
+        :param FilterCollection filter: filters to apply to the results
+        :param int time_now: current time - used as a baseline for age
+            calculations
+        :param int token_id: ID of the user's auth token - used for namespacing
+            of transaction IDs
+        :param joined: True if the user is joined to this room - will mean
+            we handle ephemeral events
+
+        :return: the room, encoded in our response format
+        :rtype: dict[str, object]
+        """
         event_map = {}
         state_events = filter.filter_room_state(room.state)
         state_event_ids = []
diff --git a/synapse/state.py b/synapse/state.py
index f893df3378..8ea2cac5d6 100644
--- a/synapse/state.py
+++ b/synapse/state.py
@@ -71,7 +71,7 @@ class StateHandler(object):
 
     @defer.inlineCallbacks
     def get_current_state(self, room_id, event_type=None, state_key=""):
-        """ Returns the current state for the room as a list. This is done by
+        """ Retrieves the current state for the room. This is done by
         calling `get_latest_events_in_room` to get the leading edges of the
         event graph and then resolving any of the state conflicts.
 
@@ -80,6 +80,8 @@ class StateHandler(object):
 
         If `event_type` is specified, then the method returns only the one
         event (or None) with that `event_type` and `state_key`.
+
+        :returns map from (type, state_key) to event
         """
         event_ids = yield self.store.get_latest_event_ids_in_room(room_id)
 
@@ -177,9 +179,10 @@ class StateHandler(object):
         """ Given a list of event_ids this method fetches the state at each
         event, resolves conflicts between them and returns them.
 
-        Return format is a tuple: (`state_group`, `state_events`), where the
-        first is the name of a state group if one and only one is involved,
-        otherwise `None`.
+        :returns a Deferred tuple of (`state_group`, `state`, `prev_state`).
+        `state_group` is the name of a state group if one and only one is
+        involved. `state` is a map from (type, state_key) to event, and
+        `prev_state` is a list of event ids.
         """
         logger.debug("resolve_state_groups event_ids %s", event_ids)
 
@@ -255,6 +258,11 @@ class StateHandler(object):
             return self._resolve_events(state_sets)
 
     def _resolve_events(self, state_sets, event_type=None, state_key=""):
+        """
+        :returns a tuple (new_state, prev_states). new_state is a map
+        from (type, state_key) to event. prev_states is a list of event_ids.
+        :rtype: (dict[(str, str), synapse.events.FrozenEvent], list[str])
+        """
         state = {}
         for st in state_sets:
             for e in st: