Basic support for room versioning

This is the first tranche of support for room versioning. It includes:
 * setting the default room version in the config file
 * new room_version param on the createRoom API
 * storing the version of newly-created rooms in the m.room.create event
 * fishing the version of existing rooms out of the m.room.create event

6 files changed, 79 insertions, 5 deletions

diff --git a/synapse/api/constants.py b/synapse/api/constants.py
index 4df930c8d1..a27bf3b32d 100644
--- a/synapse/api/constants.py
+++ b/synapse/api/constants.py
@@ -1,6 +1,7 @@
 # -*- coding: utf-8 -*-
 # Copyright 2014-2016 OpenMarket Ltd
 # Copyright 2017 Vector Creations Ltd
+# Copyright 2018 New Vector Ltd.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -94,3 +95,8 @@ class RoomCreationPreset(object):
 class ThirdPartyEntityKind(object):
     USER = "user"
     LOCATION = "location"
+
+
+# vdh-test-version is a placeholder to get room versioning support working and tested
+# until we have a working v2.
+KNOWN_ROOM_VERSIONS = {"1", "vdh-test-version"}
diff --git a/synapse/api/errors.py b/synapse/api/errors.py
index b41d595059..477ca07a24 100644
--- a/synapse/api/errors.py
+++ b/synapse/api/errors.py
@@ -1,5 +1,6 @@
 # -*- coding: utf-8 -*-
 # Copyright 2014-2016 OpenMarket Ltd
+# Copyright 2018 New Vector Ltd.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -56,6 +57,7 @@ class Codes(object):
     CONSENT_NOT_GIVEN = "M_CONSENT_NOT_GIVEN"
     CANNOT_LEAVE_SERVER_NOTICE_ROOM = "M_CANNOT_LEAVE_SERVER_NOTICE_ROOM"
     MAU_LIMIT_EXCEEDED = "M_MAU_LIMIT_EXCEEDED"
+    UNSUPPORTED_ROOM_VERSION = "M_UNSUPPORTED_ROOM_VERSION"
 
 
 class CodeMessageException(RuntimeError):
diff --git a/synapse/config/server.py b/synapse/config/server.py
index 6a471a0a5e..68ef2789d3 100644
--- a/synapse/config/server.py
+++ b/synapse/config/server.py
@@ -16,6 +16,7 @@
 
 import logging
 
+from synapse.api.constants import KNOWN_ROOM_VERSIONS
 from synapse.http.endpoint import parse_and_validate_server_name
 
 from ._base import Config, ConfigError
@@ -75,6 +76,16 @@ class ServerConfig(Config):
             )
         else:
             self.max_mau_value = 0
+
+        # the version of rooms created by default on this server
+        self.default_room_version = str(config.get(
+            "default_room_version", "1",
+        ))
+        if self.default_room_version not in KNOWN_ROOM_VERSIONS:
+            raise ConfigError("Unrecognised value '%s' for default_room_version" % (
+                self.default_room_version,
+            ))
+
         # FIXME: federation_domain_whitelist needs sytests
         self.federation_domain_whitelist = None
         federation_domain_whitelist = config.get(
@@ -249,6 +260,9 @@ class ServerConfig(Config):
         # (except those sent by local server admins). The default is False.
         # block_non_admin_invites: True
 
+        # The room_version of rooms which are created by default by this server.
+        # default_room_version: 1
+
         # Restrict federation to the following whitelist of domains.
         # N.B. we recommend also firewalling your federation listener to limit
         # inbound federation traffic as early as possible, rather than relying
diff --git a/synapse/handlers/room.py b/synapse/handlers/room.py
index 7b7804d9b2..a526b684e9 100644
--- a/synapse/handlers/room.py
+++ b/synapse/handlers/room.py
@@ -21,9 +21,16 @@ import math
 import string
 from collections import OrderedDict
 
+from six import string_types
+
 from twisted.internet import defer
 
-from synapse.api.constants import EventTypes, JoinRules, RoomCreationPreset
+from synapse.api.constants import (
+    KNOWN_ROOM_VERSIONS,
+    EventTypes,
+    JoinRules,
+    RoomCreationPreset,
+)
 from synapse.api.errors import AuthError, Codes, StoreError, SynapseError
 from synapse.types import RoomAlias, RoomID, RoomStreamToken, StreamToken, UserID
 from synapse.util import stringutils
@@ -99,6 +106,21 @@ class RoomCreationHandler(BaseHandler):
         if ratelimit:
             yield self.ratelimit(requester)
 
+        room_version = config.get("room_version", self.hs.config.default_room_version)
+        if not isinstance(room_version, string_types):
+            raise SynapseError(
+                400,
+                "room_version must be a string",
+                Codes.BAD_JSON,
+            )
+
+        if room_version not in KNOWN_ROOM_VERSIONS:
+            raise SynapseError(
+                400,
+                "Your homeserver does not support this room version",
+                Codes.UNSUPPORTED_ROOM_VERSION,
+            )
+
         if "room_alias_name" in config:
             for wchar in string.whitespace:
                 if wchar in config["room_alias_name"]:
@@ -184,6 +206,9 @@ class RoomCreationHandler(BaseHandler):
 
         creation_content = config.get("creation_content", {})
 
+        # override any attempt to set room versions via the creation_content
+        creation_content["room_version"] = room_version
+
         room_member_handler = self.hs.get_room_member_handler()
 
         yield self._send_events_for_new_room(
diff --git a/synapse/replication/slave/storage/events.py b/synapse/replication/slave/storage/events.py
index bdb5eee4af..4830c68f35 100644
--- a/synapse/replication/slave/storage/events.py
+++ b/synapse/replication/slave/storage/events.py
@@ -44,8 +44,8 @@ class SlavedEventStore(EventFederationWorkerStore,
                        RoomMemberWorkerStore,
                        EventPushActionsWorkerStore,
                        StreamWorkerStore,
-                       EventsWorkerStore,
                        StateGroupWorkerStore,
+                       EventsWorkerStore,
                        SignatureWorkerStore,
                        UserErasureWorkerStore,
                        BaseSlavedStore):
diff --git a/synapse/storage/state.py b/synapse/storage/state.py
index b27b3ae144..17b14d464b 100644
--- a/synapse/storage/state.py
+++ b/synapse/storage/state.py
@@ -21,15 +21,17 @@ from six.moves import range
 
 from twisted.internet import defer
 
+from synapse.api.constants import EventTypes
+from synapse.api.errors import NotFoundError
+from synapse.storage._base import SQLBaseStore
 from synapse.storage.background_updates import BackgroundUpdateStore
 from synapse.storage.engines import PostgresEngine
+from synapse.storage.events_worker import EventsWorkerStore
 from synapse.util.caches import get_cache_factor_for, intern_string
 from synapse.util.caches.descriptors import cached, cachedList
 from synapse.util.caches.dictionary_cache import DictionaryCache
 from synapse.util.stringutils import to_ascii
 
-from ._base import SQLBaseStore
-
 logger = logging.getLogger(__name__)
 
 
@@ -46,7 +48,8 @@ class _GetStateGroupDelta(namedtuple("_GetStateGroupDelta", ("prev_group", "delt
         return len(self.delta_ids) if self.delta_ids else 0
 
 
-class StateGroupWorkerStore(SQLBaseStore):
+# this inherits from EventsWorkerStore because it calls self.get_events
+class StateGroupWorkerStore(EventsWorkerStore, SQLBaseStore):
     """The parts of StateGroupStore that can be called from workers.
     """
 
@@ -61,6 +64,30 @@ class StateGroupWorkerStore(SQLBaseStore):
             "*stateGroupCache*", 500000 * get_cache_factor_for("stateGroupCache")
         )
 
+    @defer.inlineCallbacks
+    def get_room_version(self, room_id):
+        """Get the room_version of a given room
+
+        Args:
+            room_id (str)
+
+        Returns:
+            Deferred[str]
+
+        Raises:
+            NotFoundError if the room is unknown
+        """
+        # for now we do this by looking at the create event. We may want to cache this
+        # more intelligently in future.
+        state_ids = yield self.get_current_state_ids(room_id)
+        create_id = state_ids.get((EventTypes.Create, ""))
+
+        if not create_id:
+            raise NotFoundError("Unknown room")
+
+        create_event = yield self.get_event(create_id)
+        defer.returnValue(create_event.content.get("room_version", "1"))
+
     @cached(max_entries=100000, iterable=True)
     def get_current_state_ids(self, room_id):
         """Get the current state event ids for a room based on the