Add StateGroupStorage interface

3 files changed, 235 insertions, 1 deletions

diff --git a/synapse/storage/__init__.py b/synapse/storage/__init__.py
index a6429d17ed..0a1a8cc1e5 100644
--- a/synapse/storage/__init__.py
+++ b/synapse/storage/__init__.py
@@ -30,6 +30,7 @@ stored in `synapse.storage.schema`.
 from synapse.storage.data_stores import DataStores
 from synapse.storage.data_stores.main import DataStore
 from synapse.storage.persist_events import EventsPersistenceStorage
+from synapse.storage.state import StateGroupStorage
 
 __all__ = ["DataStores", "DataStore"]
 
@@ -45,6 +46,7 @@ class Storage(object):
         self.main = stores.main
 
         self.persistence = EventsPersistenceStorage(hs, stores)
+        self.state = StateGroupStorage(hs, stores)
 
 
 def are_all_users_on_domain(txn, database_engine, domain):
diff --git a/synapse/storage/persist_events.py b/synapse/storage/persist_events.py
index cf66225574..61dfca8fdc 100644
--- a/synapse/storage/persist_events.py
+++ b/synapse/storage/persist_events.py
@@ -550,7 +550,7 @@ class EventsPersistenceStorage(object):
 
         if missing_event_ids:
             # Now pull out the state groups for any missing events from DB
-            event_to_groups = yield self.state_store._get_state_group_for_events(
+            event_to_groups = yield self.main_store._get_state_group_for_events(
                 missing_event_ids
             )
             event_id_to_state_group.update(event_to_groups)
diff --git a/synapse/storage/state.py b/synapse/storage/state.py
index a2df8fa827..b382a06dcc 100644
--- a/synapse/storage/state.py
+++ b/synapse/storage/state.py
@@ -19,6 +19,8 @@ from six import iteritems, itervalues
 
 import attr
 
+from twisted.internet import defer
+
 from synapse.api.constants import EventTypes
 
 logger = logging.getLogger(__name__)
@@ -322,3 +324,233 @@ class StateFilter(object):
         )
 
         return member_filter, non_member_filter
+
+
+class StateGroupStorage(object):
+    """High level interface to fetching state for event.
+    """
+
+    def __init__(self, hs, stores):
+        self.stores = stores
+
+    def get_state_group_delta(self, state_group):
+        """Given a state group try to return a previous group and a delta between
+        the old and the new.
+
+        Returns:
+            (prev_group, delta_ids), where both may be None.
+        """
+
+        return self.stores.main.get_state_group_delta(state_group)
+
+    @defer.inlineCallbacks
+    def get_state_groups_ids(self, _room_id, event_ids):
+        """Get the event IDs of all the state for the state groups for the given events
+
+        Args:
+            _room_id (str): id of the room for these events
+            event_ids (iterable[str]): ids of the events
+
+        Returns:
+            Deferred[dict[int, dict[tuple[str, str], str]]]:
+                dict of state_group_id -> (dict of (type, state_key) -> event id)
+        """
+        if not event_ids:
+            return {}
+
+        event_to_groups = yield self.stores.main._get_state_group_for_events(event_ids)
+
+        groups = set(itervalues(event_to_groups))
+        group_to_state = yield self.stores.main._get_state_for_groups(groups)
+
+        return group_to_state
+
+    @defer.inlineCallbacks
+    def get_state_ids_for_group(self, state_group):
+        """Get the event IDs of all the state in the given state group
+
+        Args:
+            state_group (int)
+
+        Returns:
+            Deferred[dict]: Resolves to a map of (type, state_key) -> event_id
+        """
+        group_to_state = yield self._get_state_for_groups((state_group,))
+
+        return group_to_state[state_group]
+
+    @defer.inlineCallbacks
+    def get_state_groups(self, room_id, event_ids):
+        """ Get the state groups for the given list of event_ids
+        Returns:
+            Deferred[dict[int, list[EventBase]]]:
+                dict of state_group_id -> list of state events.
+        """
+        if not event_ids:
+            return {}
+
+        group_to_ids = yield self.get_state_groups_ids(room_id, event_ids)
+
+        state_event_map = yield self.stores.main.get_events(
+            [
+                ev_id
+                for group_ids in itervalues(group_to_ids)
+                for ev_id in itervalues(group_ids)
+            ],
+            get_prev_content=False,
+        )
+
+        return {
+            group: [
+                state_event_map[v]
+                for v in itervalues(event_id_map)
+                if v in state_event_map
+            ]
+            for group, event_id_map in iteritems(group_to_ids)
+        }
+
+    def _get_state_groups_from_groups(self, groups, state_filter):
+        """Returns the state groups for a given set of groups, filtering on
+        types of state events.
+
+        Args:
+            groups(list[int]): list of state group IDs to query
+            state_filter (StateFilter): The state filter used to fetch state
+                from the database.
+        Returns:
+            Deferred[dict[int, dict[tuple[str, str], str]]]:
+                dict of state_group_id -> (dict of (type, state_key) -> event id)
+        """
+
+        return self.stores.main._get_state_groups_from_groups(groups, state_filter)
+
+    @defer.inlineCallbacks
+    def get_state_for_events(self, event_ids, state_filter=StateFilter.all()):
+        """Given a list of event_ids and type tuples, return a list of state
+        dicts for each event.
+        Args:
+            event_ids (list[string])
+            state_filter (StateFilter): The state filter used to fetch state
+                from the database.
+        Returns:
+            deferred: A dict of (event_id) -> (type, state_key) -> [state_events]
+        """
+        event_to_groups = yield self.stores.main._get_state_group_for_events(event_ids)
+
+        groups = set(itervalues(event_to_groups))
+        group_to_state = yield self.stores.main._get_state_for_groups(
+            groups, state_filter
+        )
+
+        state_event_map = yield self.stores.main.get_events(
+            [ev_id for sd in itervalues(group_to_state) for ev_id in itervalues(sd)],
+            get_prev_content=False,
+        )
+
+        event_to_state = {
+            event_id: {
+                k: state_event_map[v]
+                for k, v in iteritems(group_to_state[group])
+                if v in state_event_map
+            }
+            for event_id, group in iteritems(event_to_groups)
+        }
+
+        return {event: event_to_state[event] for event in event_ids}
+
+    @defer.inlineCallbacks
+    def get_state_ids_for_events(self, event_ids, state_filter=StateFilter.all()):
+        """
+        Get the state dicts corresponding to a list of events, containing the event_ids
+        of the state events (as opposed to the events themselves)
+
+        Args:
+            event_ids(list(str)): events whose state should be returned
+            state_filter (StateFilter): The state filter used to fetch state
+                from the database.
+
+        Returns:
+            A deferred dict from event_id -> (type, state_key) -> event_id
+        """
+        event_to_groups = yield self.stores.main._get_state_group_for_events(event_ids)
+
+        groups = set(itervalues(event_to_groups))
+        group_to_state = yield self.stores.main._get_state_for_groups(
+            groups, state_filter
+        )
+
+        event_to_state = {
+            event_id: group_to_state[group]
+            for event_id, group in iteritems(event_to_groups)
+        }
+
+        return {event: event_to_state[event] for event in event_ids}
+
+    @defer.inlineCallbacks
+    def get_state_for_event(self, event_id, state_filter=StateFilter.all()):
+        """
+        Get the state dict corresponding to a particular event
+
+        Args:
+            event_id(str): event whose state should be returned
+            state_filter (StateFilter): The state filter used to fetch state
+                from the database.
+
+        Returns:
+            A deferred dict from (type, state_key) -> state_event
+        """
+        state_map = yield self.get_state_for_events([event_id], state_filter)
+        return state_map[event_id]
+
+    @defer.inlineCallbacks
+    def get_state_ids_for_event(self, event_id, state_filter=StateFilter.all()):
+        """
+        Get the state dict corresponding to a particular event
+
+        Args:
+            event_id(str): event whose state should be returned
+            state_filter (StateFilter): The state filter used to fetch state
+                from the database.
+
+        Returns:
+            A deferred dict from (type, state_key) -> state_event
+        """
+        state_map = yield self.get_state_ids_for_events([event_id], state_filter)
+        return state_map[event_id]
+
+    def _get_state_for_groups(self, groups, state_filter=StateFilter.all()):
+        """Gets the state at each of a list of state groups, optionally
+        filtering by type/state_key
+
+        Args:
+            groups (iterable[int]): list of state groups for which we want
+                to get the state.
+            state_filter (StateFilter): The state filter used to fetch state
+                from the database.
+        Returns:
+            Deferred[dict[int, dict[tuple[str, str], str]]]:
+                dict of state_group_id -> (dict of (type, state_key) -> event id)
+        """
+        return self.stores.main._get_state_for_groups(groups, state_filter)
+
+    def store_state_group(
+        self, event_id, room_id, prev_group, delta_ids, current_state_ids
+    ):
+        """Store a new set of state, returning a newly assigned state group.
+
+        Args:
+            event_id (str): The event ID for which the state was calculated
+            room_id (str)
+            prev_group (int|None): A previous state group for the room, optional.
+            delta_ids (dict|None): The delta between state at `prev_group` and
+                `current_state_ids`, if `prev_group` was given. Same format as
+                `current_state_ids`.
+            current_state_ids (dict): The state to store. Map of (type, state_key)
+                to event_id.
+
+        Returns:
+            Deferred[int]: The state group ID
+        """
+        return self.stores.main.store_state_group(
+            event_id, room_id, prev_group, delta_ids, current_state_ids
+        )