Remove user-visible groups/communities code (#12553)

Makes it so that groups/communities no longer exist from a user-POV. E.g. we remove:

* All API endpoints (including Client-Server, Server-Server, and admin).
* Documented configuration options (and the experimental flag, which is now unused).
* Special handling during room upgrades.
* The `groups` section of the `/sync` response.

5 files changed, 0 insertions, 1026 deletions

diff --git a/synapse/rest/__init__.py b/synapse/rest/__init__.py
index 57c4773edc..b712215112 100644
--- a/synapse/rest/__init__.py
+++ b/synapse/rest/__init__.py
@@ -26,7 +26,6 @@ from synapse.rest.client import (
     directory,
     events,
     filter,
-    groups,
     initial_sync,
     keys,
     knock,
@@ -118,8 +117,6 @@ class ClientRestResource(JsonResource):
         thirdparty.register_servlets(hs, client_resource)
         sendtodevice.register_servlets(hs, client_resource)
         user_directory.register_servlets(hs, client_resource)
-        if hs.config.experimental.groups_enabled:
-            groups.register_servlets(hs, client_resource)
         room_upgrade_rest_servlet.register_servlets(hs, client_resource)
         room_batch.register_servlets(hs, client_resource)
         capabilities.register_servlets(hs, client_resource)
diff --git a/synapse/rest/admin/__init__.py b/synapse/rest/admin/__init__.py
index cb4d55c89d..1aa08f8d95 100644
--- a/synapse/rest/admin/__init__.py
+++ b/synapse/rest/admin/__init__.py
@@ -47,7 +47,6 @@ from synapse.rest.admin.federation import (
     DestinationRestServlet,
     ListDestinationsRestServlet,
 )
-from synapse.rest.admin.groups import DeleteGroupAdminRestServlet
 from synapse.rest.admin.media import ListMediaInRoom, register_servlets_for_media_repo
 from synapse.rest.admin.registration_tokens import (
     ListRegistrationTokensRestServlet,
@@ -293,8 +292,6 @@ def register_servlets_for_client_rest_resource(
     ResetPasswordRestServlet(hs).register(http_server)
     SearchUsersRestServlet(hs).register(http_server)
     UserRegisterServlet(hs).register(http_server)
-    if hs.config.experimental.groups_enabled:
-        DeleteGroupAdminRestServlet(hs).register(http_server)
     AccountValidityRenewServlet(hs).register(http_server)
 
     # Load the media repo ones if we're using them. Otherwise load the servlets which
diff --git a/synapse/rest/admin/groups.py b/synapse/rest/admin/groups.py
deleted file mode 100644
index cd697e180e..0000000000
--- a/synapse/rest/admin/groups.py
+++ /dev/null
@@ -1,50 +0,0 @@
-# Copyright 2019 The Matrix.org Foundation C.I.C.
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#     http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-import logging
-from http import HTTPStatus
-from typing import TYPE_CHECKING, Tuple
-
-from synapse.api.errors import SynapseError
-from synapse.http.servlet import RestServlet
-from synapse.http.site import SynapseRequest
-from synapse.rest.admin._base import admin_patterns, assert_user_is_admin
-from synapse.types import JsonDict
-
-if TYPE_CHECKING:
-    from synapse.server import HomeServer
-
-logger = logging.getLogger(__name__)
-
-
-class DeleteGroupAdminRestServlet(RestServlet):
-    """Allows deleting of local groups"""
-
-    PATTERNS = admin_patterns("/delete_group/(?P<group_id>[^/]*)$")
-
-    def __init__(self, hs: "HomeServer"):
-        self.group_server = hs.get_groups_server_handler()
-        self.is_mine_id = hs.is_mine_id
-        self.auth = hs.get_auth()
-
-    async def on_POST(
-        self, request: SynapseRequest, group_id: str
-    ) -> Tuple[int, JsonDict]:
-        requester = await self.auth.get_user_by_req(request)
-        await assert_user_is_admin(self.auth, requester.user)
-
-        if not self.is_mine_id(group_id):
-            raise SynapseError(HTTPStatus.BAD_REQUEST, "Can only delete local groups")
-
-        await self.group_server.delete_group(group_id, requester.user.to_string())
-        return HTTPStatus.OK, {}
diff --git a/synapse/rest/client/groups.py b/synapse/rest/client/groups.py
deleted file mode 100644
index 7e1149c7f4..0000000000
--- a/synapse/rest/client/groups.py
+++ /dev/null
@@ -1,962 +0,0 @@
-# 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.
-# You may obtain a copy of the License at
-#
-#     http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-import logging
-from functools import wraps
-from typing import TYPE_CHECKING, Any, Awaitable, Callable, Optional, Tuple
-
-from twisted.web.server import Request
-
-from synapse.api.constants import (
-    MAX_GROUP_CATEGORYID_LENGTH,
-    MAX_GROUP_ROLEID_LENGTH,
-    MAX_GROUPID_LENGTH,
-)
-from synapse.api.errors import Codes, SynapseError
-from synapse.handlers.groups_local import GroupsLocalHandler
-from synapse.http.server import HttpServer
-from synapse.http.servlet import (
-    RestServlet,
-    assert_params_in_dict,
-    parse_json_object_from_request,
-)
-from synapse.http.site import SynapseRequest
-from synapse.types import GroupID, JsonDict
-
-from ._base import client_patterns
-
-if TYPE_CHECKING:
-    from synapse.server import HomeServer
-
-logger = logging.getLogger(__name__)
-
-
-def _validate_group_id(
-    f: Callable[..., Awaitable[Tuple[int, JsonDict]]]
-) -> Callable[..., Awaitable[Tuple[int, JsonDict]]]:
-    """Wrapper to validate the form of the group ID.
-
-    Can be applied to any on_FOO methods that accepts a group ID as a URL parameter.
-    """
-
-    @wraps(f)
-    def wrapper(
-        self: RestServlet, request: Request, group_id: str, *args: Any, **kwargs: Any
-    ) -> Awaitable[Tuple[int, JsonDict]]:
-        if not GroupID.is_valid(group_id):
-            raise SynapseError(400, "%s is not a legal group ID" % (group_id,))
-
-        return f(self, request, group_id, *args, **kwargs)
-
-    return wrapper
-
-
-class GroupServlet(RestServlet):
-    """Get the group profile"""
-
-    PATTERNS = client_patterns("/groups/(?P<group_id>[^/]*)/profile$")
-
-    def __init__(self, hs: "HomeServer"):
-        super().__init__()
-        self.auth = hs.get_auth()
-        self.clock = hs.get_clock()
-        self.groups_handler = hs.get_groups_local_handler()
-
-    @_validate_group_id
-    async def on_GET(
-        self, request: SynapseRequest, group_id: str
-    ) -> Tuple[int, JsonDict]:
-        requester = await self.auth.get_user_by_req(request, allow_guest=True)
-        requester_user_id = requester.user.to_string()
-
-        group_description = await self.groups_handler.get_group_profile(
-            group_id, requester_user_id
-        )
-
-        return 200, group_description
-
-    @_validate_group_id
-    async def on_POST(
-        self, request: SynapseRequest, group_id: str
-    ) -> Tuple[int, JsonDict]:
-        requester = await self.auth.get_user_by_req(request)
-        requester_user_id = requester.user.to_string()
-
-        content = parse_json_object_from_request(request)
-        assert_params_in_dict(
-            content, ("name", "avatar_url", "short_description", "long_description")
-        )
-        assert isinstance(
-            self.groups_handler, GroupsLocalHandler
-        ), "Workers cannot create group profiles."
-        await self.groups_handler.update_group_profile(
-            group_id, requester_user_id, content
-        )
-
-        return 200, {}
-
-
-class GroupSummaryServlet(RestServlet):
-    """Get the full group summary"""
-
-    PATTERNS = client_patterns("/groups/(?P<group_id>[^/]*)/summary$")
-
-    def __init__(self, hs: "HomeServer"):
-        super().__init__()
-        self.auth = hs.get_auth()
-        self.clock = hs.get_clock()
-        self.groups_handler = hs.get_groups_local_handler()
-
-    @_validate_group_id
-    async def on_GET(
-        self, request: SynapseRequest, group_id: str
-    ) -> Tuple[int, JsonDict]:
-        requester = await self.auth.get_user_by_req(request, allow_guest=True)
-        requester_user_id = requester.user.to_string()
-
-        get_group_summary = await self.groups_handler.get_group_summary(
-            group_id, requester_user_id
-        )
-
-        return 200, get_group_summary
-
-
-class GroupSummaryRoomsCatServlet(RestServlet):
-    """Update/delete a rooms entry in the summary.
-
-    Matches both:
-        - /groups/:group/summary/rooms/:room_id
-        - /groups/:group/summary/categories/:category/rooms/:room_id
-    """
-
-    PATTERNS = client_patterns(
-        "/groups/(?P<group_id>[^/]*)/summary"
-        "(/categories/(?P<category_id>[^/]+))?"
-        "/rooms/(?P<room_id>[^/]*)$"
-    )
-
-    def __init__(self, hs: "HomeServer"):
-        super().__init__()
-        self.auth = hs.get_auth()
-        self.clock = hs.get_clock()
-        self.groups_handler = hs.get_groups_local_handler()
-
-    @_validate_group_id
-    async def on_PUT(
-        self,
-        request: SynapseRequest,
-        group_id: str,
-        category_id: Optional[str],
-        room_id: str,
-    ) -> Tuple[int, JsonDict]:
-        requester = await self.auth.get_user_by_req(request)
-        requester_user_id = requester.user.to_string()
-
-        if category_id == "":
-            raise SynapseError(400, "category_id cannot be empty", Codes.INVALID_PARAM)
-
-        if category_id and len(category_id) > MAX_GROUP_CATEGORYID_LENGTH:
-            raise SynapseError(
-                400,
-                "category_id may not be longer than %s characters"
-                % (MAX_GROUP_CATEGORYID_LENGTH,),
-                Codes.INVALID_PARAM,
-            )
-
-        content = parse_json_object_from_request(request)
-        assert isinstance(
-            self.groups_handler, GroupsLocalHandler
-        ), "Workers cannot modify group summaries."
-        resp = await self.groups_handler.update_group_summary_room(
-            group_id,
-            requester_user_id,
-            room_id=room_id,
-            category_id=category_id,
-            content=content,
-        )
-
-        return 200, resp
-
-    @_validate_group_id
-    async def on_DELETE(
-        self, request: SynapseRequest, group_id: str, category_id: str, room_id: str
-    ) -> Tuple[int, JsonDict]:
-        requester = await self.auth.get_user_by_req(request)
-        requester_user_id = requester.user.to_string()
-
-        assert isinstance(
-            self.groups_handler, GroupsLocalHandler
-        ), "Workers cannot modify group profiles."
-        resp = await self.groups_handler.delete_group_summary_room(
-            group_id, requester_user_id, room_id=room_id, category_id=category_id
-        )
-
-        return 200, resp
-
-
-class GroupCategoryServlet(RestServlet):
-    """Get/add/update/delete a group category"""
-
-    PATTERNS = client_patterns(
-        "/groups/(?P<group_id>[^/]*)/categories/(?P<category_id>[^/]+)$"
-    )
-
-    def __init__(self, hs: "HomeServer"):
-        super().__init__()
-        self.auth = hs.get_auth()
-        self.clock = hs.get_clock()
-        self.groups_handler = hs.get_groups_local_handler()
-
-    @_validate_group_id
-    async def on_GET(
-        self, request: SynapseRequest, group_id: str, category_id: str
-    ) -> Tuple[int, JsonDict]:
-        requester = await self.auth.get_user_by_req(request, allow_guest=True)
-        requester_user_id = requester.user.to_string()
-
-        category = await self.groups_handler.get_group_category(
-            group_id, requester_user_id, category_id=category_id
-        )
-
-        return 200, category
-
-    @_validate_group_id
-    async def on_PUT(
-        self, request: SynapseRequest, group_id: str, category_id: str
-    ) -> Tuple[int, JsonDict]:
-        requester = await self.auth.get_user_by_req(request)
-        requester_user_id = requester.user.to_string()
-
-        if not category_id:
-            raise SynapseError(400, "category_id cannot be empty", Codes.INVALID_PARAM)
-
-        if len(category_id) > MAX_GROUP_CATEGORYID_LENGTH:
-            raise SynapseError(
-                400,
-                "category_id may not be longer than %s characters"
-                % (MAX_GROUP_CATEGORYID_LENGTH,),
-                Codes.INVALID_PARAM,
-            )
-
-        content = parse_json_object_from_request(request)
-        assert isinstance(
-            self.groups_handler, GroupsLocalHandler
-        ), "Workers cannot modify group categories."
-        resp = await self.groups_handler.update_group_category(
-            group_id, requester_user_id, category_id=category_id, content=content
-        )
-
-        return 200, resp
-
-    @_validate_group_id
-    async def on_DELETE(
-        self, request: SynapseRequest, group_id: str, category_id: str
-    ) -> Tuple[int, JsonDict]:
-        requester = await self.auth.get_user_by_req(request)
-        requester_user_id = requester.user.to_string()
-
-        assert isinstance(
-            self.groups_handler, GroupsLocalHandler
-        ), "Workers cannot modify group categories."
-        resp = await self.groups_handler.delete_group_category(
-            group_id, requester_user_id, category_id=category_id
-        )
-
-        return 200, resp
-
-
-class GroupCategoriesServlet(RestServlet):
-    """Get all group categories"""
-
-    PATTERNS = client_patterns("/groups/(?P<group_id>[^/]*)/categories/$")
-
-    def __init__(self, hs: "HomeServer"):
-        super().__init__()
-        self.auth = hs.get_auth()
-        self.clock = hs.get_clock()
-        self.groups_handler = hs.get_groups_local_handler()
-
-    @_validate_group_id
-    async def on_GET(
-        self, request: SynapseRequest, group_id: str
-    ) -> Tuple[int, JsonDict]:
-        requester = await self.auth.get_user_by_req(request, allow_guest=True)
-        requester_user_id = requester.user.to_string()
-
-        category = await self.groups_handler.get_group_categories(
-            group_id, requester_user_id
-        )
-
-        return 200, category
-
-
-class GroupRoleServlet(RestServlet):
-    """Get/add/update/delete a group role"""
-
-    PATTERNS = client_patterns("/groups/(?P<group_id>[^/]*)/roles/(?P<role_id>[^/]+)$")
-
-    def __init__(self, hs: "HomeServer"):
-        super().__init__()
-        self.auth = hs.get_auth()
-        self.clock = hs.get_clock()
-        self.groups_handler = hs.get_groups_local_handler()
-
-    @_validate_group_id
-    async def on_GET(
-        self, request: SynapseRequest, group_id: str, role_id: str
-    ) -> Tuple[int, JsonDict]:
-        requester = await self.auth.get_user_by_req(request, allow_guest=True)
-        requester_user_id = requester.user.to_string()
-
-        category = await self.groups_handler.get_group_role(
-            group_id, requester_user_id, role_id=role_id
-        )
-
-        return 200, category
-
-    @_validate_group_id
-    async def on_PUT(
-        self, request: SynapseRequest, group_id: str, role_id: str
-    ) -> Tuple[int, JsonDict]:
-        requester = await self.auth.get_user_by_req(request)
-        requester_user_id = requester.user.to_string()
-
-        if not role_id:
-            raise SynapseError(400, "role_id cannot be empty", Codes.INVALID_PARAM)
-
-        if len(role_id) > MAX_GROUP_ROLEID_LENGTH:
-            raise SynapseError(
-                400,
-                "role_id may not be longer than %s characters"
-                % (MAX_GROUP_ROLEID_LENGTH,),
-                Codes.INVALID_PARAM,
-            )
-
-        content = parse_json_object_from_request(request)
-        assert isinstance(
-            self.groups_handler, GroupsLocalHandler
-        ), "Workers cannot modify group roles."
-        resp = await self.groups_handler.update_group_role(
-            group_id, requester_user_id, role_id=role_id, content=content
-        )
-
-        return 200, resp
-
-    @_validate_group_id
-    async def on_DELETE(
-        self, request: SynapseRequest, group_id: str, role_id: str
-    ) -> Tuple[int, JsonDict]:
-        requester = await self.auth.get_user_by_req(request)
-        requester_user_id = requester.user.to_string()
-
-        assert isinstance(
-            self.groups_handler, GroupsLocalHandler
-        ), "Workers cannot modify group roles."
-        resp = await self.groups_handler.delete_group_role(
-            group_id, requester_user_id, role_id=role_id
-        )
-
-        return 200, resp
-
-
-class GroupRolesServlet(RestServlet):
-    """Get all group roles"""
-
-    PATTERNS = client_patterns("/groups/(?P<group_id>[^/]*)/roles/$")
-
-    def __init__(self, hs: "HomeServer"):
-        super().__init__()
-        self.auth = hs.get_auth()
-        self.clock = hs.get_clock()
-        self.groups_handler = hs.get_groups_local_handler()
-
-    @_validate_group_id
-    async def on_GET(
-        self, request: SynapseRequest, group_id: str
-    ) -> Tuple[int, JsonDict]:
-        requester = await self.auth.get_user_by_req(request, allow_guest=True)
-        requester_user_id = requester.user.to_string()
-
-        category = await self.groups_handler.get_group_roles(
-            group_id, requester_user_id
-        )
-
-        return 200, category
-
-
-class GroupSummaryUsersRoleServlet(RestServlet):
-    """Update/delete a user's entry in the summary.
-
-    Matches both:
-        - /groups/:group/summary/users/:room_id
-        - /groups/:group/summary/roles/:role/users/:user_id
-    """
-
-    PATTERNS = client_patterns(
-        "/groups/(?P<group_id>[^/]*)/summary"
-        "(/roles/(?P<role_id>[^/]+))?"
-        "/users/(?P<user_id>[^/]*)$"
-    )
-
-    def __init__(self, hs: "HomeServer"):
-        super().__init__()
-        self.auth = hs.get_auth()
-        self.clock = hs.get_clock()
-        self.groups_handler = hs.get_groups_local_handler()
-
-    @_validate_group_id
-    async def on_PUT(
-        self,
-        request: SynapseRequest,
-        group_id: str,
-        role_id: Optional[str],
-        user_id: str,
-    ) -> Tuple[int, JsonDict]:
-        requester = await self.auth.get_user_by_req(request)
-        requester_user_id = requester.user.to_string()
-
-        if role_id == "":
-            raise SynapseError(400, "role_id cannot be empty", Codes.INVALID_PARAM)
-
-        if role_id and len(role_id) > MAX_GROUP_ROLEID_LENGTH:
-            raise SynapseError(
-                400,
-                "role_id may not be longer than %s characters"
-                % (MAX_GROUP_ROLEID_LENGTH,),
-                Codes.INVALID_PARAM,
-            )
-
-        content = parse_json_object_from_request(request)
-        assert isinstance(
-            self.groups_handler, GroupsLocalHandler
-        ), "Workers cannot modify group summaries."
-        resp = await self.groups_handler.update_group_summary_user(
-            group_id,
-            requester_user_id,
-            user_id=user_id,
-            role_id=role_id,
-            content=content,
-        )
-
-        return 200, resp
-
-    @_validate_group_id
-    async def on_DELETE(
-        self, request: SynapseRequest, group_id: str, role_id: str, user_id: str
-    ) -> Tuple[int, JsonDict]:
-        requester = await self.auth.get_user_by_req(request)
-        requester_user_id = requester.user.to_string()
-
-        assert isinstance(
-            self.groups_handler, GroupsLocalHandler
-        ), "Workers cannot modify group summaries."
-        resp = await self.groups_handler.delete_group_summary_user(
-            group_id, requester_user_id, user_id=user_id, role_id=role_id
-        )
-
-        return 200, resp
-
-
-class GroupRoomServlet(RestServlet):
-    """Get all rooms in a group"""
-
-    PATTERNS = client_patterns("/groups/(?P<group_id>[^/]*)/rooms$")
-
-    def __init__(self, hs: "HomeServer"):
-        super().__init__()
-        self.auth = hs.get_auth()
-        self.clock = hs.get_clock()
-        self.groups_handler = hs.get_groups_local_handler()
-
-    @_validate_group_id
-    async def on_GET(
-        self, request: SynapseRequest, group_id: str
-    ) -> Tuple[int, JsonDict]:
-        requester = await self.auth.get_user_by_req(request, allow_guest=True)
-        requester_user_id = requester.user.to_string()
-
-        result = await self.groups_handler.get_rooms_in_group(
-            group_id, requester_user_id
-        )
-
-        return 200, result
-
-
-class GroupUsersServlet(RestServlet):
-    """Get all users in a group"""
-
-    PATTERNS = client_patterns("/groups/(?P<group_id>[^/]*)/users$")
-
-    def __init__(self, hs: "HomeServer"):
-        super().__init__()
-        self.auth = hs.get_auth()
-        self.clock = hs.get_clock()
-        self.groups_handler = hs.get_groups_local_handler()
-
-    @_validate_group_id
-    async def on_GET(
-        self, request: SynapseRequest, group_id: str
-    ) -> Tuple[int, JsonDict]:
-        requester = await self.auth.get_user_by_req(request, allow_guest=True)
-        requester_user_id = requester.user.to_string()
-
-        result = await self.groups_handler.get_users_in_group(
-            group_id, requester_user_id
-        )
-
-        return 200, result
-
-
-class GroupInvitedUsersServlet(RestServlet):
-    """Get users invited to a group"""
-
-    PATTERNS = client_patterns("/groups/(?P<group_id>[^/]*)/invited_users$")
-
-    def __init__(self, hs: "HomeServer"):
-        super().__init__()
-        self.auth = hs.get_auth()
-        self.clock = hs.get_clock()
-        self.groups_handler = hs.get_groups_local_handler()
-
-    @_validate_group_id
-    async def on_GET(
-        self, request: SynapseRequest, group_id: str
-    ) -> Tuple[int, JsonDict]:
-        requester = await self.auth.get_user_by_req(request)
-        requester_user_id = requester.user.to_string()
-
-        result = await self.groups_handler.get_invited_users_in_group(
-            group_id, requester_user_id
-        )
-
-        return 200, result
-
-
-class GroupSettingJoinPolicyServlet(RestServlet):
-    """Set group join policy"""
-
-    PATTERNS = client_patterns("/groups/(?P<group_id>[^/]*)/settings/m.join_policy$")
-
-    def __init__(self, hs: "HomeServer"):
-        super().__init__()
-        self.auth = hs.get_auth()
-        self.groups_handler = hs.get_groups_local_handler()
-
-    @_validate_group_id
-    async def on_PUT(
-        self, request: SynapseRequest, group_id: str
-    ) -> Tuple[int, JsonDict]:
-        requester = await self.auth.get_user_by_req(request)
-        requester_user_id = requester.user.to_string()
-
-        content = parse_json_object_from_request(request)
-
-        assert isinstance(
-            self.groups_handler, GroupsLocalHandler
-        ), "Workers cannot modify group join policy."
-        result = await self.groups_handler.set_group_join_policy(
-            group_id, requester_user_id, content
-        )
-
-        return 200, result
-
-
-class GroupCreateServlet(RestServlet):
-    """Create a group"""
-
-    PATTERNS = client_patterns("/create_group$")
-
-    def __init__(self, hs: "HomeServer"):
-        super().__init__()
-        self.auth = hs.get_auth()
-        self.clock = hs.get_clock()
-        self.groups_handler = hs.get_groups_local_handler()
-        self.server_name = hs.hostname
-
-    async def on_POST(self, request: SynapseRequest) -> Tuple[int, JsonDict]:
-        requester = await self.auth.get_user_by_req(request)
-        requester_user_id = requester.user.to_string()
-
-        # TODO: Create group on remote server
-        content = parse_json_object_from_request(request)
-        localpart = content.pop("localpart")
-        group_id = GroupID(localpart, self.server_name).to_string()
-
-        if not localpart:
-            raise SynapseError(400, "Group ID cannot be empty", Codes.INVALID_PARAM)
-
-        if len(group_id) > MAX_GROUPID_LENGTH:
-            raise SynapseError(
-                400,
-                "Group ID may not be longer than %s characters" % (MAX_GROUPID_LENGTH,),
-                Codes.INVALID_PARAM,
-            )
-
-        assert isinstance(
-            self.groups_handler, GroupsLocalHandler
-        ), "Workers cannot create groups."
-        result = await self.groups_handler.create_group(
-            group_id, requester_user_id, content
-        )
-
-        return 200, result
-
-
-class GroupAdminRoomsServlet(RestServlet):
-    """Add a room to the group"""
-
-    PATTERNS = client_patterns(
-        "/groups/(?P<group_id>[^/]*)/admin/rooms/(?P<room_id>[^/]*)$"
-    )
-
-    def __init__(self, hs: "HomeServer"):
-        super().__init__()
-        self.auth = hs.get_auth()
-        self.clock = hs.get_clock()
-        self.groups_handler = hs.get_groups_local_handler()
-
-    @_validate_group_id
-    async def on_PUT(
-        self, request: SynapseRequest, group_id: str, room_id: str
-    ) -> Tuple[int, JsonDict]:
-        requester = await self.auth.get_user_by_req(request)
-        requester_user_id = requester.user.to_string()
-
-        content = parse_json_object_from_request(request)
-        assert isinstance(
-            self.groups_handler, GroupsLocalHandler
-        ), "Workers cannot modify rooms in a group."
-        result = await self.groups_handler.add_room_to_group(
-            group_id, requester_user_id, room_id, content
-        )
-
-        return 200, result
-
-    @_validate_group_id
-    async def on_DELETE(
-        self, request: SynapseRequest, group_id: str, room_id: str
-    ) -> Tuple[int, JsonDict]:
-        requester = await self.auth.get_user_by_req(request)
-        requester_user_id = requester.user.to_string()
-
-        assert isinstance(
-            self.groups_handler, GroupsLocalHandler
-        ), "Workers cannot modify group categories."
-        result = await self.groups_handler.remove_room_from_group(
-            group_id, requester_user_id, room_id
-        )
-
-        return 200, result
-
-
-class GroupAdminRoomsConfigServlet(RestServlet):
-    """Update the config of a room in a group"""
-
-    PATTERNS = client_patterns(
-        "/groups/(?P<group_id>[^/]*)/admin/rooms/(?P<room_id>[^/]*)"
-        "/config/(?P<config_key>[^/]*)$"
-    )
-
-    def __init__(self, hs: "HomeServer"):
-        super().__init__()
-        self.auth = hs.get_auth()
-        self.clock = hs.get_clock()
-        self.groups_handler = hs.get_groups_local_handler()
-
-    @_validate_group_id
-    async def on_PUT(
-        self, request: SynapseRequest, group_id: str, room_id: str, config_key: str
-    ) -> Tuple[int, JsonDict]:
-        requester = await self.auth.get_user_by_req(request)
-        requester_user_id = requester.user.to_string()
-
-        content = parse_json_object_from_request(request)
-        assert isinstance(
-            self.groups_handler, GroupsLocalHandler
-        ), "Workers cannot modify group categories."
-        result = await self.groups_handler.update_room_in_group(
-            group_id, requester_user_id, room_id, config_key, content
-        )
-
-        return 200, result
-
-
-class GroupAdminUsersInviteServlet(RestServlet):
-    """Invite a user to the group"""
-
-    PATTERNS = client_patterns(
-        "/groups/(?P<group_id>[^/]*)/admin/users/invite/(?P<user_id>[^/]*)$"
-    )
-
-    def __init__(self, hs: "HomeServer"):
-        super().__init__()
-        self.auth = hs.get_auth()
-        self.clock = hs.get_clock()
-        self.groups_handler = hs.get_groups_local_handler()
-        self.store = hs.get_datastores().main
-        self.is_mine_id = hs.is_mine_id
-
-    @_validate_group_id
-    async def on_PUT(
-        self, request: SynapseRequest, group_id: str, user_id: str
-    ) -> Tuple[int, JsonDict]:
-        requester = await self.auth.get_user_by_req(request)
-        requester_user_id = requester.user.to_string()
-
-        content = parse_json_object_from_request(request)
-        config = content.get("config", {})
-        assert isinstance(
-            self.groups_handler, GroupsLocalHandler
-        ), "Workers cannot invite users to a group."
-        result = await self.groups_handler.invite(
-            group_id, user_id, requester_user_id, config
-        )
-
-        return 200, result
-
-
-class GroupAdminUsersKickServlet(RestServlet):
-    """Kick a user from the group"""
-
-    PATTERNS = client_patterns(
-        "/groups/(?P<group_id>[^/]*)/admin/users/remove/(?P<user_id>[^/]*)$"
-    )
-
-    def __init__(self, hs: "HomeServer"):
-        super().__init__()
-        self.auth = hs.get_auth()
-        self.clock = hs.get_clock()
-        self.groups_handler = hs.get_groups_local_handler()
-
-    @_validate_group_id
-    async def on_PUT(
-        self, request: SynapseRequest, group_id: str, user_id: str
-    ) -> Tuple[int, JsonDict]:
-        requester = await self.auth.get_user_by_req(request)
-        requester_user_id = requester.user.to_string()
-
-        content = parse_json_object_from_request(request)
-        assert isinstance(
-            self.groups_handler, GroupsLocalHandler
-        ), "Workers cannot kick users from a group."
-        result = await self.groups_handler.remove_user_from_group(
-            group_id, user_id, requester_user_id, content
-        )
-
-        return 200, result
-
-
-class GroupSelfLeaveServlet(RestServlet):
-    """Leave a joined group"""
-
-    PATTERNS = client_patterns("/groups/(?P<group_id>[^/]*)/self/leave$")
-
-    def __init__(self, hs: "HomeServer"):
-        super().__init__()
-        self.auth = hs.get_auth()
-        self.clock = hs.get_clock()
-        self.groups_handler = hs.get_groups_local_handler()
-
-    @_validate_group_id
-    async def on_PUT(
-        self, request: SynapseRequest, group_id: str
-    ) -> Tuple[int, JsonDict]:
-        requester = await self.auth.get_user_by_req(request)
-        requester_user_id = requester.user.to_string()
-
-        content = parse_json_object_from_request(request)
-        assert isinstance(
-            self.groups_handler, GroupsLocalHandler
-        ), "Workers cannot leave a group for a users."
-        result = await self.groups_handler.remove_user_from_group(
-            group_id, requester_user_id, requester_user_id, content
-        )
-
-        return 200, result
-
-
-class GroupSelfJoinServlet(RestServlet):
-    """Attempt to join a group, or knock"""
-
-    PATTERNS = client_patterns("/groups/(?P<group_id>[^/]*)/self/join$")
-
-    def __init__(self, hs: "HomeServer"):
-        super().__init__()
-        self.auth = hs.get_auth()
-        self.clock = hs.get_clock()
-        self.groups_handler = hs.get_groups_local_handler()
-
-    @_validate_group_id
-    async def on_PUT(
-        self, request: SynapseRequest, group_id: str
-    ) -> Tuple[int, JsonDict]:
-        requester = await self.auth.get_user_by_req(request)
-        requester_user_id = requester.user.to_string()
-
-        content = parse_json_object_from_request(request)
-        assert isinstance(
-            self.groups_handler, GroupsLocalHandler
-        ), "Workers cannot join a user to a group."
-        result = await self.groups_handler.join_group(
-            group_id, requester_user_id, content
-        )
-
-        return 200, result
-
-
-class GroupSelfAcceptInviteServlet(RestServlet):
-    """Accept a group invite"""
-
-    PATTERNS = client_patterns("/groups/(?P<group_id>[^/]*)/self/accept_invite$")
-
-    def __init__(self, hs: "HomeServer"):
-        super().__init__()
-        self.auth = hs.get_auth()
-        self.clock = hs.get_clock()
-        self.groups_handler = hs.get_groups_local_handler()
-
-    @_validate_group_id
-    async def on_PUT(
-        self, request: SynapseRequest, group_id: str
-    ) -> Tuple[int, JsonDict]:
-        requester = await self.auth.get_user_by_req(request)
-        requester_user_id = requester.user.to_string()
-
-        content = parse_json_object_from_request(request)
-        assert isinstance(
-            self.groups_handler, GroupsLocalHandler
-        ), "Workers cannot accept an invite to a group."
-        result = await self.groups_handler.accept_invite(
-            group_id, requester_user_id, content
-        )
-
-        return 200, result
-
-
-class GroupSelfUpdatePublicityServlet(RestServlet):
-    """Update whether we publicise a users membership of a group"""
-
-    PATTERNS = client_patterns("/groups/(?P<group_id>[^/]*)/self/update_publicity$")
-
-    def __init__(self, hs: "HomeServer"):
-        super().__init__()
-        self.auth = hs.get_auth()
-        self.clock = hs.get_clock()
-        self.store = hs.get_datastores().main
-
-    @_validate_group_id
-    async def on_PUT(
-        self, request: SynapseRequest, group_id: str
-    ) -> Tuple[int, JsonDict]:
-        requester = await self.auth.get_user_by_req(request)
-        requester_user_id = requester.user.to_string()
-
-        content = parse_json_object_from_request(request)
-        publicise = content["publicise"]
-        await self.store.update_group_publicity(group_id, requester_user_id, publicise)
-
-        return 200, {}
-
-
-class PublicisedGroupsForUserServlet(RestServlet):
-    """Get the list of groups a user is advertising"""
-
-    PATTERNS = client_patterns("/publicised_groups/(?P<user_id>[^/]*)$")
-
-    def __init__(self, hs: "HomeServer"):
-        super().__init__()
-        self.auth = hs.get_auth()
-        self.clock = hs.get_clock()
-        self.store = hs.get_datastores().main
-        self.groups_handler = hs.get_groups_local_handler()
-
-    async def on_GET(
-        self, request: SynapseRequest, user_id: str
-    ) -> Tuple[int, JsonDict]:
-        await self.auth.get_user_by_req(request, allow_guest=True)
-
-        result = await self.groups_handler.get_publicised_groups_for_user(user_id)
-
-        return 200, result
-
-
-class PublicisedGroupsForUsersServlet(RestServlet):
-    """Get the list of groups a user is advertising"""
-
-    PATTERNS = client_patterns("/publicised_groups$")
-
-    def __init__(self, hs: "HomeServer"):
-        super().__init__()
-        self.auth = hs.get_auth()
-        self.clock = hs.get_clock()
-        self.store = hs.get_datastores().main
-        self.groups_handler = hs.get_groups_local_handler()
-
-    async def on_POST(self, request: SynapseRequest) -> Tuple[int, JsonDict]:
-        await self.auth.get_user_by_req(request, allow_guest=True)
-
-        content = parse_json_object_from_request(request)
-        user_ids = content["user_ids"]
-
-        result = await self.groups_handler.bulk_get_publicised_groups(user_ids)
-
-        return 200, result
-
-
-class GroupsForUserServlet(RestServlet):
-    """Get all groups the logged in user is joined to"""
-
-    PATTERNS = client_patterns("/joined_groups$")
-
-    def __init__(self, hs: "HomeServer"):
-        super().__init__()
-        self.auth = hs.get_auth()
-        self.clock = hs.get_clock()
-        self.groups_handler = hs.get_groups_local_handler()
-
-    async def on_GET(self, request: SynapseRequest) -> Tuple[int, JsonDict]:
-        requester = await self.auth.get_user_by_req(request, allow_guest=True)
-        requester_user_id = requester.user.to_string()
-
-        result = await self.groups_handler.get_joined_groups(requester_user_id)
-
-        return 200, result
-
-
-def register_servlets(hs: "HomeServer", http_server: HttpServer) -> None:
-    GroupServlet(hs).register(http_server)
-    GroupSummaryServlet(hs).register(http_server)
-    GroupInvitedUsersServlet(hs).register(http_server)
-    GroupUsersServlet(hs).register(http_server)
-    GroupRoomServlet(hs).register(http_server)
-    GroupSettingJoinPolicyServlet(hs).register(http_server)
-    GroupCreateServlet(hs).register(http_server)
-    GroupAdminRoomsServlet(hs).register(http_server)
-    GroupAdminRoomsConfigServlet(hs).register(http_server)
-    GroupAdminUsersInviteServlet(hs).register(http_server)
-    GroupAdminUsersKickServlet(hs).register(http_server)
-    GroupSelfLeaveServlet(hs).register(http_server)
-    GroupSelfJoinServlet(hs).register(http_server)
-    GroupSelfAcceptInviteServlet(hs).register(http_server)
-    GroupsForUserServlet(hs).register(http_server)
-    GroupCategoryServlet(hs).register(http_server)
-    GroupCategoriesServlet(hs).register(http_server)
-    GroupSummaryRoomsCatServlet(hs).register(http_server)
-    GroupRoleServlet(hs).register(http_server)
-    GroupRolesServlet(hs).register(http_server)
-    GroupSelfUpdatePublicityServlet(hs).register(http_server)
-    GroupSummaryUsersRoleServlet(hs).register(http_server)
-    PublicisedGroupsForUserServlet(hs).register(http_server)
-    PublicisedGroupsForUsersServlet(hs).register(http_server)
diff --git a/synapse/rest/client/sync.py b/synapse/rest/client/sync.py
index e8772f86e7..f596b792fa 100644
--- a/synapse/rest/client/sync.py
+++ b/synapse/rest/client/sync.py
@@ -298,14 +298,6 @@ class SyncRestServlet(RestServlet):
         if archived:
             response["rooms"][Membership.LEAVE] = archived
 
-        if sync_result.groups is not None:
-            if sync_result.groups.join:
-                response["groups"][Membership.JOIN] = sync_result.groups.join
-            if sync_result.groups.invite:
-                response["groups"][Membership.INVITE] = sync_result.groups.invite
-            if sync_result.groups.leave:
-                response["groups"][Membership.LEAVE] = sync_result.groups.leave
-
         return response
 
     @staticmethod