Merge pull request #3654 from matrix-org/rav/room_versions

Support for room versioning

14 files changed, 244 insertions, 22 deletions

diff --git a/changelog.d/3654.feature b/changelog.d/3654.feature
new file mode 100644
index 0000000000..35c95580bc
--- /dev/null
+++ b/changelog.d/3654.feature
@@ -0,0 +1 @@
+Basic support for room versioning
diff --git a/synapse/api/constants.py b/synapse/api/constants.py
index 4df930c8d1..b0da506f6d 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 +95,11 @@ class RoomCreationPreset(object):
 class ThirdPartyEntityKind(object):
     USER = "user"
     LOCATION = "location"
+
+
+# the version we will give rooms which are created on this server
+DEFAULT_ROOM_VERSION = "1"
+
+# 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..70400347bc 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 +57,8 @@ 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"
+    INCOMPATIBLE_ROOM_VERSION = "M_INCOMPATIBLE_ROOM_VERSION"
 
 
 class CodeMessageException(RuntimeError):
@@ -285,6 +288,27 @@ class LimitExceededError(SynapseError):
         )
 
 
+class IncompatibleRoomVersionError(SynapseError):
+    """A server is trying to join a room whose version it does not support."""
+
+    def __init__(self, room_version):
+        super(IncompatibleRoomVersionError, self).__init__(
+            code=400,
+            msg="Your homeserver does not support the features required to "
+                "join this room",
+            errcode=Codes.INCOMPATIBLE_ROOM_VERSION,
+        )
+
+        self._room_version = room_version
+
+    def error_dict(self):
+        return cs_error(
+            self.msg,
+            self.errcode,
+            room_version=self._room_version,
+        )
+
+
 def cs_error(msg, code=Codes.UNKNOWN, **kwargs):
     """ Utility method for constructing an error response for client-server
     interactions.
diff --git a/synapse/event_auth.py b/synapse/event_auth.py
index b32f64e729..6baeccca38 100644
--- a/synapse/event_auth.py
+++ b/synapse/event_auth.py
@@ -20,7 +20,7 @@ from signedjson.key import decode_verify_key_bytes
 from signedjson.sign import SignatureVerifyException, verify_signed_json
 from unpaddedbase64 import decode_base64
 
-from synapse.api.constants import EventTypes, JoinRules, Membership
+from synapse.api.constants import KNOWN_ROOM_VERSIONS, EventTypes, JoinRules, Membership
 from synapse.api.errors import AuthError, EventSizeError, SynapseError
 from synapse.types import UserID, get_domain_from_id
 
@@ -83,6 +83,14 @@ def check(event, auth_events, do_sig_check=True, do_size_check=True):
                 403,
                 "Creation event's room_id domain does not match sender's"
             )
+
+        room_version = event.content.get("room_version", "1")
+        if room_version not in KNOWN_ROOM_VERSIONS:
+            raise AuthError(
+                403,
+                "room appears to have unsupported version %s" % (
+                    room_version,
+                ))
         # FIXME
         logger.debug("Allowing! %s", event)
         return
diff --git a/synapse/federation/federation_client.py b/synapse/federation/federation_client.py
index 7550e11b6e..c9f3c2d352 100644
--- a/synapse/federation/federation_client.py
+++ b/synapse/federation/federation_client.py
@@ -25,7 +25,7 @@ from prometheus_client import Counter
 
 from twisted.internet import defer
 
-from synapse.api.constants import Membership
+from synapse.api.constants import KNOWN_ROOM_VERSIONS, EventTypes, Membership
 from synapse.api.errors import (
     CodeMessageException,
     FederationDeniedError,
@@ -518,10 +518,10 @@ class FederationClient(FederationBase):
                     description, destination, exc_info=1,
                 )
 
-        raise RuntimeError("Failed to %s via any server", description)
+        raise RuntimeError("Failed to %s via any server" % (description, ))
 
     def make_membership_event(self, destinations, room_id, user_id, membership,
-                              content={},):
+                              content, params):
         """
         Creates an m.room.member event, with context, without participating in the room.
 
@@ -537,8 +537,10 @@ class FederationClient(FederationBase):
             user_id (str): The user whose membership is being evented.
             membership (str): The "membership" property of the event. Must be
                 one of "join" or "leave".
-            content (object): Any additional data to put into the content field
+            content (dict): Any additional data to put into the content field
                 of the event.
+            params (dict[str, str|Iterable[str]]): Query parameters to include in the
+                request.
         Return:
             Deferred: resolves to a tuple of (origin (str), event (object))
             where origin is the remote homeserver which generated the event.
@@ -558,10 +560,12 @@ class FederationClient(FederationBase):
         @defer.inlineCallbacks
         def send_request(destination):
             ret = yield self.transport_layer.make_membership_event(
-                destination, room_id, user_id, membership
+                destination, room_id, user_id, membership, params,
             )
 
-            pdu_dict = ret["event"]
+            pdu_dict = ret.get("event", None)
+            if not isinstance(pdu_dict, dict):
+                raise InvalidResponseError("Bad 'event' field in response")
 
             logger.debug("Got response to make_%s: %s", membership, pdu_dict)
 
@@ -605,6 +609,26 @@ class FederationClient(FederationBase):
             Fails with a ``RuntimeError`` if no servers were reachable.
         """
 
+        def check_authchain_validity(signed_auth_chain):
+            for e in signed_auth_chain:
+                if e.type == EventTypes.Create:
+                    create_event = e
+                    break
+            else:
+                raise InvalidResponseError(
+                    "no %s in auth chain" % (EventTypes.Create,),
+                )
+
+            # the room version should be sane.
+            room_version = create_event.content.get("room_version", "1")
+            if room_version not in KNOWN_ROOM_VERSIONS:
+                # This shouldn't be possible, because the remote server should have
+                # rejected the join attempt during make_join.
+                raise InvalidResponseError(
+                    "room appears to have unsupported version %s" % (
+                        room_version,
+                    ))
+
         @defer.inlineCallbacks
         def send_request(destination):
             time_now = self._clock.time_msec()
@@ -661,7 +685,7 @@ class FederationClient(FederationBase):
             for s in signed_state:
                 s.internal_metadata = copy.deepcopy(s.internal_metadata)
 
-            auth_chain.sort(key=lambda e: e.depth)
+            check_authchain_validity(signed_auth)
 
             defer.returnValue({
                 "state": signed_state,
diff --git a/synapse/federation/federation_server.py b/synapse/federation/federation_server.py
index bf89d568af..2b62f687b6 100644
--- a/synapse/federation/federation_server.py
+++ b/synapse/federation/federation_server.py
@@ -27,7 +27,13 @@ from twisted.internet.abstract import isIPAddress
 from twisted.python import failure
 
 from synapse.api.constants import EventTypes
-from synapse.api.errors import AuthError, FederationError, NotFoundError, SynapseError
+from synapse.api.errors import (
+    AuthError,
+    FederationError,
+    IncompatibleRoomVersionError,
+    NotFoundError,
+    SynapseError,
+)
 from synapse.crypto.event_signing import compute_event_signature
 from synapse.federation.federation_base import FederationBase, event_from_pdu_json
 from synapse.federation.persistence import TransactionActions
@@ -323,12 +329,21 @@ class FederationServer(FederationBase):
         defer.returnValue((200, resp))
 
     @defer.inlineCallbacks
-    def on_make_join_request(self, origin, room_id, user_id):
+    def on_make_join_request(self, origin, room_id, user_id, supported_versions):
         origin_host, _ = parse_server_name(origin)
         yield self.check_server_matches_acl(origin_host, room_id)
+
+        room_version = yield self.store.get_room_version(room_id)
+        if room_version not in supported_versions:
+            logger.warn("Room version %s not in %s", room_version, supported_versions)
+            raise IncompatibleRoomVersionError(room_version=room_version)
+
         pdu = yield self.handler.on_make_join_request(room_id, user_id)
         time_now = self._clock.time_msec()
-        defer.returnValue({"event": pdu.get_pdu_json(time_now)})
+        defer.returnValue({
+            "event": pdu.get_pdu_json(time_now),
+            "room_version": room_version,
+        })
 
     @defer.inlineCallbacks
     def on_invite_request(self, origin, content):
diff --git a/synapse/federation/transport/client.py b/synapse/federation/transport/client.py
index 4529d454af..b4fbe2c9d5 100644
--- a/synapse/federation/transport/client.py
+++ b/synapse/federation/transport/client.py
@@ -195,7 +195,7 @@ class TransportLayerClient(object):
 
     @defer.inlineCallbacks
     @log_function
-    def make_membership_event(self, destination, room_id, user_id, membership):
+    def make_membership_event(self, destination, room_id, user_id, membership, params):
         """Asks a remote server to build and sign us a membership event
 
         Note that this does not append any events to any graphs.
@@ -205,6 +205,8 @@ class TransportLayerClient(object):
             room_id (str): room to join/leave
             user_id (str): user to be joined/left
             membership (str): one of join/leave
+            params (dict[str, str|Iterable[str]]): Query parameters to include in the
+                request.
 
         Returns:
             Deferred: Succeeds when we get a 2xx HTTP response. The result
@@ -241,6 +243,7 @@ class TransportLayerClient(object):
         content = yield self.client.get_json(
             destination=destination,
             path=path,
+            args=params,
             retry_on_dns_fail=retry_on_dns_fail,
             timeout=20000,
             ignore_backoff=ignore_backoff,
diff --git a/synapse/federation/transport/server.py b/synapse/federation/transport/server.py
index eae5f2b427..77969a4f38 100644
--- a/synapse/federation/transport/server.py
+++ b/synapse/federation/transport/server.py
@@ -190,6 +190,41 @@ def _parse_auth_header(header_bytes):
 
 
 class BaseFederationServlet(object):
+    """Abstract base class for federation servlet classes.
+
+    The servlet object should have a PATH attribute which takes the form of a regexp to
+    match against the request path (excluding the /federation/v1 prefix).
+
+    The servlet should also implement one or more of on_GET, on_POST, on_PUT, to match
+    the appropriate HTTP method. These methods have the signature:
+
+        on_<METHOD>(self, origin, content, query, **kwargs)
+
+        With arguments:
+
+            origin (unicode|None): The authenticated server_name of the calling server,
+                unless REQUIRE_AUTH is set to False and authentication failed.
+
+            content (unicode|None): decoded json body of the request. None if the
+                request was a GET.
+
+            query (dict[bytes, list[bytes]]): Query params from the request. url-decoded
+                (ie, '+' and '%xx' are decoded) but note that it is *not* utf8-decoded
+                yet.
+
+            **kwargs (dict[unicode, unicode]): the dict mapping keys to path
+                components as specified in the path match regexp.
+
+        Returns:
+            Deferred[(int, object)|None]: either (response code, response object) to
+                 return a JSON response, or None if the request has already been handled.
+
+        Raises:
+            SynapseError: to return an error code
+
+            Exception: other exceptions will be caught, logged, and a 500 will be
+                returned.
+    """
     REQUIRE_AUTH = True
 
     def __init__(self, handler, authenticator, ratelimiter, server_name):
@@ -204,6 +239,18 @@ class BaseFederationServlet(object):
         @defer.inlineCallbacks
         @functools.wraps(func)
         def new_func(request, *args, **kwargs):
+            """ A callback which can be passed to HttpServer.RegisterPaths
+
+            Args:
+                request (twisted.web.http.Request):
+                *args: unused?
+                **kwargs (dict[unicode, unicode]): the dict mapping keys to path
+                    components as specified in the path match regexp.
+
+            Returns:
+                Deferred[(int, object)|None]: (response code, response object) as returned
+                    by the callback method. None if the request has already been handled.
+            """
             content = None
             if request.method in ["PUT", "POST"]:
                 # TODO: Handle other method types? other content types?
@@ -384,9 +431,31 @@ class FederationMakeJoinServlet(BaseFederationServlet):
     PATH = "/make_join/(?P<context>[^/]*)/(?P<user_id>[^/]*)"
 
     @defer.inlineCallbacks
-    def on_GET(self, origin, content, query, context, user_id):
+    def on_GET(self, origin, _content, query, context, user_id):
+        """
+        Args:
+            origin (unicode): The authenticated server_name of the calling server
+
+            _content (None): (GETs don't have bodies)
+
+            query (dict[bytes, list[bytes]]): Query params from the request.
+
+            **kwargs (dict[unicode, unicode]): the dict mapping keys to path
+                components as specified in the path match regexp.
+
+        Returns:
+            Deferred[(int, object)|None]: either (response code, response object) to
+                 return a JSON response, or None if the request has already been handled.
+        """
+        versions = query.get(b'ver')
+        if versions is not None:
+            supported_versions = [v.decode("utf-8") for v in versions]
+        else:
+            supported_versions = ["1"]
+
         content = yield self.handler.on_make_join_request(
             origin, context, user_id,
+            supported_versions=supported_versions,
         )
         defer.returnValue((200, content))
 
diff --git a/synapse/handlers/federation.py b/synapse/handlers/federation.py
index 533b82c783..0dffd44e22 100644
--- a/synapse/handlers/federation.py
+++ b/synapse/handlers/federation.py
@@ -30,7 +30,12 @@ from unpaddedbase64 import decode_base64
 
 from twisted.internet import defer
 
-from synapse.api.constants import EventTypes, Membership, RejectedReason
+from synapse.api.constants import (
+    KNOWN_ROOM_VERSIONS,
+    EventTypes,
+    Membership,
+    RejectedReason,
+)
 from synapse.api.errors import (
     AuthError,
     CodeMessageException,
@@ -922,6 +927,9 @@ class FederationHandler(BaseHandler):
             joinee,
             "join",
             content,
+            params={
+                "ver": KNOWN_ROOM_VERSIONS,
+            },
         )
 
         # This shouldn't happen, because the RoomMemberHandler has a
@@ -1187,13 +1195,14 @@ class FederationHandler(BaseHandler):
 
     @defer.inlineCallbacks
     def _make_and_verify_event(self, target_hosts, room_id, user_id, membership,
-                               content={},):
+                               content={}, params=None):
         origin, pdu = yield self.federation_client.make_membership_event(
             target_hosts,
             room_id,
             user_id,
             membership,
             content,
+            params=params,
         )
 
         logger.debug("Got response to make_%s: %s", membership, pdu)
diff --git a/synapse/handlers/room.py b/synapse/handlers/room.py
index 7b7804d9b2..6a17c42238 100644
--- a/synapse/handlers/room.py
+++ b/synapse/handlers/room.py
@@ -21,9 +21,17 @@ 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 (
+    DEFAULT_ROOM_VERSION,
+    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 +107,21 @@ class RoomCreationHandler(BaseHandler):
         if ratelimit:
             yield self.ratelimit(requester)
 
+        room_version = config.get("room_version", 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 +207,9 @@ 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/http/matrixfederationclient.py b/synapse/http/matrixfederationclient.py
index bf1aa29502..b3f5415aa6 100644
--- a/synapse/http/matrixfederationclient.py
+++ b/synapse/http/matrixfederationclient.py
@@ -439,7 +439,7 @@ class MatrixFederationHttpClient(object):
         defer.returnValue(json.loads(body))
 
     @defer.inlineCallbacks
-    def get_json(self, destination, path, args={}, retry_on_dns_fail=True,
+    def get_json(self, destination, path, args=None, retry_on_dns_fail=True,
                  timeout=None, ignore_backoff=False):
         """ GETs some json from the given host homeserver and path
 
@@ -447,7 +447,7 @@ class MatrixFederationHttpClient(object):
             destination (str): The remote server to send the HTTP request
                 to.
             path (str): The HTTP path.
-            args (dict): A dictionary used to create query strings, defaults to
+            args (dict|None): A dictionary used to create query strings, defaults to
                 None.
             timeout (int): How long to try (in ms) the destination for before
                 giving up. None indicates no timeout and that the request will
@@ -702,6 +702,9 @@ def check_content_type_is_json(headers):
 
 
 def encode_query_args(args):
+    if args is None:
+        return b""
+
     encoded_args = {}
     for k, vs in args.items():
         if isinstance(vs, string_types):
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
diff --git a/tests/utils.py b/tests/utils.py
index e7894819c0..151db4b890 100644
--- a/tests/utils.py
+++ b/tests/utils.py
@@ -77,6 +77,10 @@ def setup_test_homeserver(name="test", datastore=None, config=None, reactor=None
         config.max_mau_value = 50
         config.mau_limits_reserved_threepids = []
 
+        # we need a sane default_room_version, otherwise attempts to create rooms will
+        # fail.
+        config.default_room_version = "1"
+
         # disable user directory updates, because they get done in the
         # background, which upsets the test runner.
         config.update_user_directory = False