synapse-product/synapse/handlers/appservice.py

# -*- coding: utf-8 -*-
# Copyright 2015 OpenMarket 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.

from twisted.internet import defer

from synapse.api.errors import Codes, StoreError, SynapseError
from synapse.appservice import ApplicationService
from synapse.appservice.api import ApplicationServiceApi
from synapse.types import UserID
import synapse.util.stringutils as stringutils

import logging


logger = logging.getLogger(__name__)


# NB: Purposefully not inheriting BaseHandler since that contains way too much
# setup code which this handler does not need or use. This makes testing a lot
# easier.
class ApplicationServicesHandler(object):

    def __init__(self, hs):
        self.store = hs.get_datastore()
        self.hs = hs
        self.appservice_api = ApplicationServiceApi(hs)

    @defer.inlineCallbacks
    def register(self, app_service):
        logger.info("Register -> %s", app_service)
        # check the token is recognised
        try:
            stored_service = yield self.store.get_app_service_by_token(
                app_service.token
            )
            if not stored_service:
                raise StoreError(404, "Application service not found")
        except StoreError:
            raise SynapseError(
                403, "Unrecognised application services token. "
                "Consult the home server admin.",
                errcode=Codes.FORBIDDEN
            )
        logger.info("Updating application service info...")
        app_service.hs_token = self._generate_hs_token()
        yield self.store.update_app_service(app_service)
        defer.returnValue(app_service)

    def unregister(self, token):
        logger.info("Unregister as_token=%s", token)
        yield self.store.unregister_app_service(token)

    @defer.inlineCallbacks
    def get_services_for_event(self, event, restrict_to=""):
        """Retrieve a list of application services interested in this event.

        Args:
            event(Event): The event to check.
            restrict_to(str): The namespace to restrict regex tests to.
        Returns:
            list<ApplicationService>: A list of services interested in this
            event based on the service regex.
        """
        # We need to know the aliases associated with this event.room_id, if any
        alias_list = yield self.store.get_aliases_for_room(event.room_id)
        services = yield self.store.get_app_services()
        interested_list = [
            s for s in services if (
                s.is_interested(event, restrict_to, alias_list)
            )
        ]
        defer.returnValue(interested_list)

    @defer.inlineCallbacks
    def notify_interested_services(self, event):
        """Notifies (pushes) all application services interested in this event.

        Pushing is done asynchronously, so this method won't block for any
        prolonged length of time.

        Args:
            event(Event): The event to push out to interested services.
        """
        # Gather interested services
        services = yield self.get_services_for_event(event)
        if len(services) == 0:
            return  # no services need notifying

        # Do we know this user exists? If not, poke the user query API for
        # all services which match that user regex.
        unknown_user = yield self._is_unknown_user(event.sender)
        if unknown_user:
            user_query_services = yield self.get_services_for_event(
                event=event,
                restrict_to=ApplicationService.NS_USERS
            )
            for user_service in user_query_services:
                # this needs to block XXX: Need to feed response back to caller
                is_known_user = yield self.appservice_api.query_user(
                    user_service, event.sender
                )
                if is_known_user:
                    # the user exists now,so don't query more ASes.
                    break

        # Do we know this room alias exists? If not, poke the room alias query
        # API for all services which match that room alias regex.
        unknown_room_alias = False  # TODO
        if unknown_room_alias:
            alias = "something"  # TODO
            alias_query_services = yield self.get_services_for_event(
                event=event,
                restrict_to=ApplicationService.NS_ALIASES
            )
            for alias_service in alias_query_services:
                # this needs to block XXX: Need to feed response back to caller
                is_known_alias = yield self.appservice_api.query_alias(
                    alias_service, alias
                )
                if is_known_alias:
                    # the alias exists now so don't query more ASes.
                    break

        # Fork off pushes to these services - XXX First cut, best effort
        for service in services:
            self.appservice_api.push(service, event)

    @defer.inlineCallbacks
    def _is_unknown_user(self, user_id):
        user = UserID.from_string(user_id)
        if not self.hs.is_mine(user):
            # we don't know if they are unknown or not since it isn't one of our
            # users. We can't poke ASes.
            defer.returnValue(False)
            return

        user_info = yield self.store.get_user_by_id(user_id)
        defer.returnValue(len(user_info) == 0)



    def _generate_hs_token(self):
        return stringutils.random_string(24)