How to use the synapse.http.servlet.RestServlet function in synapse

)
        except AuthError:
            # This endpoint is supposed to return a 404 when the requester does
            # not have permission to access the event
            # https://matrix.org/docs/spec/client_server/r0.5.0#get-matrix-client-r0-rooms-roomid-event-eventid
            raise SynapseError(404, "Event not found.", errcode=Codes.NOT_FOUND)

        time_now = self.clock.time_msec()
        if event:
            event = await self._event_serializer.serialize_event(event, time_now)
            return 200, event

        return SynapseError(404, "Event not found.", errcode=Codes.NOT_FOUND)


class RoomEventContextServlet(RestServlet):
    PATTERNS = client_patterns(
        "/rooms/(?P[^/]*)/context/(?P[^/]*)$", v1=True
    )

    def __init__(self, hs):
        super(RoomEventContextServlet, self).__init__()
        self.clock = hs.get_clock()
        self.room_context_handler = hs.get_room_context_handler()
        self._event_serializer = hs.get_event_client_serializer()
        self.auth = hs.get_auth()

    async def on_GET(self, request, room_id, event_id):
        requester = await self.auth.get_user_by_req(request, allow_guest=True)

        limit = parse_integer(request, "limit", default=10)

# delete, so it should only throw if something is wrong
            # that we ought to care about.
            logger.exception("Failed to remove threepid")
            raise SynapseError(500, "Failed to remove threepid")

        if ret:
            id_server_unbind_result = "success"
        else:
            id_server_unbind_result = "no-support"

        defer.returnValue((200, {
            "id_server_unbind_result": id_server_unbind_result,
        }))


class WhoamiRestServlet(RestServlet):
    PATTERNS = client_patterns("/account/whoami$")

    def __init__(self, hs):
        super(WhoamiRestServlet, self).__init__()
        self.auth = hs.get_auth()

    @defer.inlineCallbacks
    def on_GET(self, request):
        requester = yield self.auth.get_user_by_req(request)

        defer.returnValue((200, {'user_id': requester.user.to_string()}))


def register_servlets(hs, http_server):
    EmailPasswordRequestTokenRestServlet(hs).register(http_server)
    MsisdnPasswordRequestTokenRestServlet(hs).register(http_server)

self.message_handler = hs.get_message_handler()
        self.auth = hs.get_auth()

    async def on_GET(self, request, room_id):
        requester = await self.auth.get_user_by_req(request, allow_guest=True)
        # Get all the current state for this room
        events = await self.message_handler.get_state_events(
            room_id=room_id,
            user_id=requester.user.to_string(),
            is_guest=requester.is_guest,
        )
        return 200, events


# TODO: Needs unit testing
class RoomInitialSyncRestServlet(RestServlet):
    PATTERNS = client_patterns("/rooms/(?P[^/]*)/initialSync$", v1=True)

    def __init__(self, hs):
        super(RoomInitialSyncRestServlet, self).__init__()
        self.initial_sync_handler = hs.get_initial_sync_handler()
        self.auth = hs.get_auth()

    async def on_GET(self, request, room_id):
        requester = await self.auth.get_user_by_req(request, allow_guest=True)
        pagination_config = PaginationConfig.from_request(request)
        content = await self.initial_sync_handler.room_initial_sync(
            room_id=room_id, requester=requester, pagin_config=pagination_config
        )
        return 200, content

yield self.store.update_aliases_for_room(
            room_id, new_room_id, requester_user_id
        )

        return (
            200,
            {
                "kicked_users": kicked_users,
                "failed_to_kick_users": failed_to_kick_users,
                "local_aliases": aliases_for_room,
                "new_room_id": new_room_id,
            },
        )


class ResetPasswordRestServlet(RestServlet):
    """Post request to allow an administrator reset password for a user.
    This needs user to have administrator access in Synapse.
        Example:
            http://localhost:8008/_synapse/admin/v1/reset_password/
            @user:to_reset_password?access_token=admin_access_token
        JsonBodyToSend:
            {
                "new_password": "secret"
            }
        Returns:
            200 OK with empty object if success otherwise an error.
        """

    PATTERNS = historical_admin_path_patterns(
        "/reset_password/(?P[^/]*)"
    )

"""
        self.pagination_handler = hs.get_pagination_handler()
        self.auth = hs.get_auth()

    @defer.inlineCallbacks
    def on_GET(self, request, purge_id):
        yield assert_requester_is_admin(self.auth, request)

        purge_status = self.pagination_handler.get_purge_status(purge_id)
        if purge_status is None:
            raise NotFoundError("purge id '%s' not found" % purge_id)

        return (200, purge_status.asdict())


class DeactivateAccountRestServlet(RestServlet):
    PATTERNS = historical_admin_path_patterns("/deactivate/(?P[^/]*)")

    def __init__(self, hs):
        self._deactivate_account_handler = hs.get_deactivate_account_handler()
        self.auth = hs.get_auth()

    @defer.inlineCallbacks
    def on_POST(self, request, target_user_id):
        yield assert_requester_is_admin(self.auth, request)
        body = parse_json_object_from_request(request, allow_empty_body=True)
        erase = body.get("erase", False)
        if not isinstance(erase, bool):
            raise SynapseError(
                http_client.BAD_REQUEST,
                "Param 'erase' must be a boolean, if given",
                Codes.BAD_JSON,

Note that this should only be used for existing endpoints: new ones should just
    register for the /_synapse/admin path.
    """
    return list(
        re.compile(prefix + path_regex)
        for prefix in (
            "^/_synapse/admin/v1",
            "^/_matrix/client/api/v1/admin",
            "^/_matrix/client/unstable/admin",
            "^/_matrix/client/r0/admin"
        )
    )


class UsersRestServlet(RestServlet):
    PATTERNS = historical_admin_path_patterns("/users/(?P[^/]*)")

    def __init__(self, hs):
        self.hs = hs
        self.auth = hs.get_auth()
        self.handlers = hs.get_handlers()

    @defer.inlineCallbacks
    def on_GET(self, request, user_id):
        target_user = UserID.from_string(user_id)
        requester = yield self.auth.get_user_by_req(request)
        is_admin = yield self.auth.is_server_admin(requester.user)

        if not is_admin:
            raise AuthError(403, "You are not a server admin")

"""
        yield assert_requester_is_admin(self.auth, request)
        UserID.from_string(target_user_id)

        order = "name"  # order by name in user table
        params = parse_json_object_from_request(request)
        assert_params_in_dict(params, ["limit", "start"])
        limit = params["limit"]
        start = params["start"]
        logger.info("limit: %s, start: %s", limit, start)

        ret = yield self.handlers.admin_handler.get_users_paginate(order, start, limit)
        return (200, ret)


class SearchUsersRestServlet(RestServlet):
    """Get request to search user table for specific users according to
    search term.
    This needs user to have administrator access in Synapse.
        Example:
            http://localhost:8008/_synapse/admin/v1/search_users/
            @admin:user?access_token=admin_access_token&term=alice
        Returns:
            200 OK with json object {list[dict[str, Any]], count} or empty object.
    """

    PATTERNS = historical_admin_path_patterns("/search_users/(?P[^/]*)")

    def __init__(self, hs):
        self.store = hs.get_datastore()
        self.hs = hs
        self.auth = hs.get_auth()

# 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 synapse.api.errors import AuthError, NotFoundError, StoreError, SynapseError
from synapse.http.servlet import RestServlet, parse_json_object_from_request
from synapse.types import UserID

from ._base import client_patterns, set_timeline_upper_limit

logger = logging.getLogger(__name__)


class GetFilterRestServlet(RestServlet):
    PATTERNS = client_patterns("/user/(?P[^/]*)/filter/(?P[^/]*)")

    def __init__(self, hs):
        super(GetFilterRestServlet, self).__init__()
        self.hs = hs
        self.auth = hs.get_auth()
        self.filtering = hs.get_filtering()

    async def on_GET(self, request, user_id, filter_id):
        target_user = UserID.from_string(user_id)
        requester = await self.auth.get_user_by_req(request)

        if target_user != requester.user:
            raise AuthError(403, "Cannot get filters for other users")

        if not self.hs.is_mine(target_user):

self.auth = hs.get_auth()
        self.clock = hs.get_clock()
        self.groups_handler = hs.get_groups_local_handler()

    async def on_GET(self, request, group_id):
        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[^/]*)/settings/m.join_policy$")

    def __init__(self, hs):
        super(GroupSettingJoinPolicyServlet, self).__init__()
        self.auth = hs.get_auth()
        self.groups_handler = hs.get_groups_local_handler()

    async def on_PUT(self, request, group_id):
        requester = await self.auth.get_user_by_req(request)
        requester_user_id = requester.user.to_string()

        content = parse_json_object_from_request(request)

def __init__(self, hs):
        super(RoomInitialSyncRestServlet, self).__init__()
        self.initial_sync_handler = hs.get_initial_sync_handler()
        self.auth = hs.get_auth()

    async def on_GET(self, request, room_id):
        requester = await self.auth.get_user_by_req(request, allow_guest=True)
        pagination_config = PaginationConfig.from_request(request)
        content = await self.initial_sync_handler.room_initial_sync(
            room_id=room_id, requester=requester, pagin_config=pagination_config
        )
        return 200, content


class RoomEventServlet(RestServlet):
    PATTERNS = client_patterns(
        "/rooms/(?P[^/]*)/event/(?P[^/]*)$", v1=True
    )

    def __init__(self, hs):
        super(RoomEventServlet, self).__init__()
        self.clock = hs.get_clock()
        self.event_handler = hs.get_event_handler()
        self._event_serializer = hs.get_event_client_serializer()
        self.auth = hs.get_auth()

    async def on_GET(self, request, room_id, event_id):
        requester = await self.auth.get_user_by_req(request, allow_guest=True)
        try:
            event = await self.event_handler.get_event(
                requester.user, room_id, event_id