#!/usr/bin/env python# -*- coding: utf-8 -*-# Copyright 2016 OpenMarket Ltd# Copyright 2020 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 contextlibimport loggingimport sysfrom typing import Dict, Iterable, Optional, Setfrom typing_extensions import ContextManagerfrom twisted.internet import address, reactorimport synapseimport synapse.eventsfrom synapse.api.errors import HttpResponseException, RequestSendFailed, SynapseErrorfrom synapse.api.urls import (    CLIENT_API_PREFIX,    FEDERATION_PREFIX,    LEGACY_MEDIA_PREFIX,    MEDIA_PREFIX,    SERVER_KEY_V2_PREFIX,)from synapse.app import _basefrom synapse.config._base import ConfigErrorfrom synapse.config.homeserver import HomeServerConfigfrom synapse.config.logger import setup_loggingfrom synapse.config.server import ListenerConfigfrom synapse.federation import send_queuefrom synapse.federation.transport.server import TransportLayerServerfrom synapse.handlers.presence import (    BasePresenceHandler,    PresenceState,    get_interested_parties,)from synapse.http.server import JsonResource, OptionsResourcefrom synapse.http.servlet import RestServlet, parse_json_object_from_requestfrom synapse.http.site import SynapseSitefrom synapse.logging.context import LoggingContextfrom synapse.metrics import METRICS_PREFIX, MetricsResource, RegistryProxyfrom synapse.metrics.background_process_metrics import run_as_background_processfrom synapse.replication.http import REPLICATION_PREFIX, ReplicationRestResourcefrom synapse.replication.http.presence import (    ReplicationBumpPresenceActiveTime,    ReplicationPresenceSetState,)from synapse.replication.slave.storage._base import BaseSlavedStorefrom synapse.replication.slave.storage.account_data import SlavedAccountDataStorefrom synapse.replication.slave.storage.appservice import SlavedApplicationServiceStorefrom synapse.replication.slave.storage.client_ips import SlavedClientIpStorefrom synapse.replication.slave.storage.deviceinbox import SlavedDeviceInboxStorefrom synapse.replication.slave.storage.devices import SlavedDeviceStorefrom synapse.replication.slave.storage.directory import DirectoryStorefrom synapse.replication.slave.storage.events import SlavedEventStorefrom synapse.replication.slave.storage.filtering import SlavedFilteringStorefrom synapse.replication.slave.storage.groups import SlavedGroupServerStorefrom synapse.replication.slave.storage.keys import SlavedKeyStorefrom synapse.replication.slave.storage.presence import SlavedPresenceStorefrom synapse.replication.slave.storage.profile import SlavedProfileStorefrom synapse.replication.slave.storage.push_rule import SlavedPushRuleStorefrom synapse.replication.slave.storage.pushers import SlavedPusherStorefrom synapse.replication.slave.storage.receipts import SlavedReceiptsStorefrom synapse.replication.slave.storage.registration import SlavedRegistrationStorefrom synapse.replication.slave.storage.room import RoomStorefrom synapse.replication.slave.storage.transactions import SlavedTransactionStorefrom synapse.replication.tcp.client import ReplicationDataHandlerfrom synapse.replication.tcp.commands import ClearUserSyncsCommandfrom synapse.replication.tcp.streams import (    AccountDataStream,    DeviceListsStream,    GroupServerStream,    PresenceStream,    PushersStream,    PushRulesStream,    ReceiptsStream,    TagAccountDataStream,    ToDeviceStream,)from synapse.rest.admin import register_servlets_for_media_repofrom synapse.rest.client.v1 import eventsfrom synapse.rest.client.v1.initial_sync import InitialSyncRestServletfrom synapse.rest.client.v1.login import LoginRestServletfrom synapse.rest.client.v1.profile import (    ProfileAvatarURLRestServlet,    ProfileDisplaynameRestServlet,    ProfileRestServlet,)from synapse.rest.client.v1.push_rule import PushRuleRestServletfrom synapse.rest.client.v1.room import (    JoinedRoomMemberListRestServlet,    JoinRoomAliasServlet,    PublicRoomListRestServlet,    RoomEventContextServlet,    RoomInitialSyncRestServlet,    RoomMemberListRestServlet,    RoomMembershipRestServlet,    RoomMessageListRestServlet,    RoomSendEventRestServlet,    RoomStateEventRestServlet,    RoomStateRestServlet,    RoomTypingRestServlet,)from synapse.rest.client.v1.voip import VoipRestServletfrom synapse.rest.client.v2_alpha import groups, sync, user_directoryfrom synapse.rest.client.v2_alpha._base import client_patternsfrom synapse.rest.client.v2_alpha.account import ThreepidRestServletfrom synapse.rest.client.v2_alpha.account_data import (    AccountDataServlet,    RoomAccountDataServlet,)from synapse.rest.client.v2_alpha.keys import KeyChangesServlet, KeyQueryServletfrom synapse.rest.client.v2_alpha.register import RegisterRestServletfrom synapse.rest.client.versions import VersionsRestServletfrom synapse.rest.health import HealthResourcefrom synapse.rest.key.v2 import KeyApiV2Resourcefrom synapse.server import HomeServer, cache_in_selffrom synapse.storage.databases.main.censor_events import CensorEventsStorefrom synapse.storage.databases.main.client_ips import ClientIpWorkerStorefrom synapse.storage.databases.main.media_repository import MediaRepositoryStorefrom synapse.storage.databases.main.metrics import ServerMetricsStorefrom synapse.storage.databases.main.monthly_active_users import (    MonthlyActiveUsersWorkerStore,)from synapse.storage.databases.main.presence import UserPresenceStatefrom synapse.storage.databases.main.search import SearchWorkerStorefrom synapse.storage.databases.main.stats import StatsStorefrom synapse.storage.databases.main.transactions import TransactionWorkerStorefrom synapse.storage.databases.main.ui_auth import UIAuthWorkerStorefrom synapse.storage.databases.main.user_directory import UserDirectoryStorefrom synapse.types import ReadReceiptfrom synapse.util.async_helpers import Linearizerfrom synapse.util.httpresourcetree import create_resource_treefrom synapse.util.manhole import manholefrom synapse.util.versionstring import get_version_stringlogger = logging.getLogger("synapse.app.generic_worker")class PresenceStatusStubServlet(RestServlet):    """If presence is disabled this servlet can be used to stub out setting    presence status.    """    PATTERNS = client_patterns("/presence/(?P<user_id>[^/]*)/status")    def __init__(self, hs):        super().__init__()        self.auth = hs.get_auth()    async def on_GET(self, request, user_id):        await self.auth.get_user_by_req(request)        return 200, {"presence": "offline"}    async def on_PUT(self, request, user_id):        await self.auth.get_user_by_req(request)        return 200, {}class KeyUploadServlet(RestServlet):    """An implementation of the `KeyUploadServlet` that responds to read only    requests, but otherwise proxies through to the master instance.    """    PATTERNS = client_patterns("/keys/upload(/(?P<device_id>[^/]+))?$")    def __init__(self, hs):        """        Args:            hs (synapse.server.HomeServer): server        """        super().__init__()        self.auth = hs.get_auth()        self.store = hs.get_datastore()        self.http_client = hs.get_simple_http_client()        self.main_uri = hs.config.worker_main_http_uri    async def on_POST(self, request, device_id):        requester = await self.auth.get_user_by_req(request, allow_guest=True)        user_id = requester.user.to_string()        body = parse_json_object_from_request(request)        if device_id is not None:            # passing the device_id here is deprecated; however, we allow it            # for now for compatibility with older clients.            if requester.device_id is not None and device_id != requester.device_id:                logger.warning(                    "Client uploading keys for a different device "                    "(logged in as %s, uploading for %s)",                    requester.device_id,                    device_id,                )        else:            device_id = requester.device_id        if device_id is None:            raise SynapseError(                400, "To upload keys, you must pass device_id when authenticating"            )        if body:            # They're actually trying to upload something, proxy to main synapse.            # Proxy headers from the original request, such as the auth headers            # (in case the access token is there) and the original IP /            # User-Agent of the request.            headers = {                header: request.requestHeaders.getRawHeaders(header, [])                for header in (b"Authorization", b"User-Agent")            }            # Add the previous hop the the X-Forwarded-For header.            x_forwarded_for = request.requestHeaders.getRawHeaders(                b"X-Forwarded-For", []            )            if isinstance(request.client, (address.IPv4Address, address.IPv6Address)):                previous_host = request.client.host.encode("ascii")                # If the header exists, add to the comma-separated list of the first                # instance of the header. Otherwise, generate a new header.                if x_forwarded_for:                    x_forwarded_for = [                        x_forwarded_for[0] + b", " + previous_host                    ] + x_forwarded_for[1:]                else:                    x_forwarded_for = [previous_host]            headers[b"X-Forwarded-For"] = x_forwarded_for            try:                result = await self.http_client.post_json_get_json(                    self.main_uri + request.uri.decode("ascii"), body, headers=headers                )            except HttpResponseException as e:                raise e.to_synapse_error() from e            except RequestSendFailed as e:                raise SynapseError(502, "Failed to talk to master") from e            return 200, result        else:            # Just interested in counts.            result = await self.store.count_e2e_one_time_keys(user_id, device_id)            return 200, {"one_time_key_counts": result}class _NullContextManager(ContextManager[None]):    """A context manager which does nothing."""    def __exit__(self, exc_type, exc_val, exc_tb):        passUPDATE_SYNCING_USERS_MS = 10 * 1000class GenericWorkerPresence(BasePresenceHandler):    def __init__(self, hs):        super().__init__(hs)        self.hs = hs        self.is_mine_id = hs.is_mine_id        # BUG: CWE-601 URL Redirection to Untrusted Site ('Open Redirect')        #         self.http_client = hs.get_simple_http_client()        # FIXED:         self._presence_enabled = hs.config.use_presence        # The number of ongoing syncs on this process, by user id.        # Empty if _presence_enabled is false.        self._user_to_num_current_syncs = {}  # type: Dict[str, int]        self.notifier = hs.get_notifier()        self.instance_id = hs.get_instance_id()        # user_id -> last_sync_ms. Lists the users that have stopped syncing        # but we haven't notified the master of that yet        self.users_going_offline = {}        self._bump_active_client = ReplicationBumpPresenceActiveTime.make_client(hs)        self._set_state_client = ReplicationPresenceSetState.make_client(hs)        self._send_stop_syncing_loop = self.clock.looping_call(            self.send_stop_syncing, UPDATE_SYNCING_USERS_MS        )        hs.get_reactor().addSystemEventTrigger(            "before",            "shutdown",            run_as_background_process,            "generic_presence.on_shutdown",            self._on_shutdown,        )    def _on_shutdown(self):        if self._presence_enabled:            self.hs.get_tcp_replication().send_command(                ClearUserSyncsCommand(self.instance_id)            )    def send_user_sync(self, user_id, is_syncing, last_sync_ms):        if self._presence_enabled:            self.hs.get_tcp_replication().send_user_sync(                self.instance_id, user_id, is_syncing, last_sync_ms            )    def mark_as_coming_online(self, user_id):        """A user has started syncing. Send a UserSync to the master, unless they        had recently stopped syncing.        Args:            user_id (str)        """        going_offline = self.users_going_offline.pop(user_id, None)        if not going_offline:            # Safe to skip because we haven't yet told the master they were offline            self.send_user_sync(user_id, True, self.clock.time_msec())    def mark_as_going_offline(self, user_id):        """A user has stopped syncing. We wait before notifying the master as        its likely they'll come back soon. This allows us to avoid sending        a stopped syncing immediately followed by a started syncing notification        to the master        Args:            user_id (str)        """        self.users_going_offline[user_id] = self.clock.time_msec()    def send_stop_syncing(self):        """Check if there are any users who have stopped syncing a while ago        and haven't come back yet. If there are poke the master about them.        """        now = self.clock.time_msec()        for user_id, last_sync_ms in list(self.users_going_offline.items()):            if now - last_sync_ms > UPDATE_SYNCING_USERS_MS:                self.users_going_offline.pop(user_id, None)                self.send_user_sync(user_id, False, last_sync_ms)    async def user_syncing(        self, user_id: str, affect_presence: bool    ) -> ContextManager[None]:        """Record that a user is syncing.        Called by the sync and events servlets to record that a user has connected to        this worker and is waiting for some events.        """        if not affect_presence or not self._presence_enabled:            return _NullContextManager()        curr_sync = self._user_to_num_current_syncs.get(user_id, 0)        self._user_to_num_current_syncs[user_id] = curr_sync + 1        # If we went from no in flight sync to some, notify replication        if self._user_to_num_current_syncs[user_id] == 1:            self.mark_as_coming_online(user_id)        def _end():            # We check that the user_id is in user_to_num_current_syncs because            # user_to_num_current_syncs may have been cleared if we are            # shutting down.            if user_id in self._user_to_num_current_syncs:                self._user_to_num_current_syncs[user_id] -= 1                # If we went from one in flight sync to non, notify replication                if self._user_to_num_current_syncs[user_id] == 0:                    self.mark_as_going_offline(user_id)        @contextlib.contextmanager        def _user_syncing():            try:                yield            finally:                _end()        return _user_syncing()    async def notify_from_replication(self, states, stream_id):        parties = await get_interested_parties(self.store, states)        room_ids_to_states, users_to_states = parties        self.notifier.on_new_event(            "presence_key",            stream_id,            rooms=room_ids_to_states.keys(),            users=users_to_states.keys(),        )    async def process_replication_rows(self, token, rows):        states = [            UserPresenceState(                row.user_id,                row.state,                row.last_active_ts,                row.last_federation_update_ts,                row.last_user_sync_ts,                row.status_msg,                row.currently_active,            )            for row in rows        ]        for state in states:            self.user_to_current_state[state.user_id] = state        stream_id = token        await self.notify_from_replication(states, stream_id)    def get_currently_syncing_users_for_replication(self) -> Iterable[str]:        return [            user_id            for user_id, count in self._user_to_num_current_syncs.items()            if count > 0        ]    async def set_state(self, target_user, state, ignore_status_msg=False):        """Set the presence state of the user.        """        presence = state["presence"]        valid_presence = (            PresenceState.ONLINE,            PresenceState.UNAVAILABLE,            PresenceState.OFFLINE,        )        if presence not in valid_presence:            raise SynapseError(400, "Invalid presence state")        user_id = target_user.to_string()        # If presence is disabled, no-op        if not self.hs.config.use_presence:            return        # Proxy request to master        await self._set_state_client(            user_id=user_id, state=state, ignore_status_msg=ignore_status_msg        )    async def bump_presence_active_time(self, user):        """We've seen the user do something that indicates they're interacting        with the app.        """        # If presence is disabled, no-op        if not self.hs.config.use_presence:            return        # Proxy request to master        user_id = user.to_string()        await self._bump_active_client(user_id=user_id)class GenericWorkerSlavedStore(    # FIXME(#3714): We need to add UserDirectoryStore as we write directly    # rather than going via the correct worker.    UserDirectoryStore,    StatsStore,    UIAuthWorkerStore,    SlavedDeviceInboxStore,    SlavedDeviceStore,    SlavedReceiptsStore,    SlavedPushRuleStore,    SlavedGroupServerStore,    SlavedAccountDataStore,    SlavedPusherStore,    CensorEventsStore,    ClientIpWorkerStore,    SlavedEventStore,    SlavedKeyStore,    RoomStore,    DirectoryStore,    SlavedApplicationServiceStore,    SlavedRegistrationStore,    SlavedTransactionStore,    SlavedProfileStore,    SlavedClientIpStore,    SlavedPresenceStore,    SlavedFilteringStore,    MonthlyActiveUsersWorkerStore,    MediaRepositoryStore,    ServerMetricsStore,    SearchWorkerStore,    TransactionWorkerStore,    BaseSlavedStore,):    passclass GenericWorkerServer(HomeServer):    DATASTORE_CLASS = GenericWorkerSlavedStore    def _listen_http(self, listener_config: ListenerConfig):        port = listener_config.port        bind_addresses = listener_config.bind_addresses        assert listener_config.http_options is not None        site_tag = listener_config.http_options.tag        if site_tag is None:            site_tag = port        # We always include a health resource.        resources = {"/health": HealthResource()}        for res in listener_config.http_options.resources:            for name in res.names:                if name == "metrics":                    resources[METRICS_PREFIX] = MetricsResource(RegistryProxy)                elif name == "client":                    resource = JsonResource(self, canonical_json=False)                    PublicRoomListRestServlet(self).register(resource)                    RoomMemberListRestServlet(self).register(resource)                    JoinedRoomMemberListRestServlet(self).register(resource)                    RoomStateRestServlet(self).register(resource)                    RoomEventContextServlet(self).register(resource)                    RoomMessageListRestServlet(self).register(resource)                    RegisterRestServlet(self).register(resource)                    LoginRestServlet(self).register(resource)                    ThreepidRestServlet(self).register(resource)                    KeyQueryServlet(self).register(resource)                    KeyChangesServlet(self).register(resource)                    VoipRestServlet(self).register(resource)                    PushRuleRestServlet(self).register(resource)                    VersionsRestServlet(self).register(resource)                    RoomSendEventRestServlet(self).register(resource)                    RoomMembershipRestServlet(self).register(resource)                    RoomStateEventRestServlet(self).register(resource)                    JoinRoomAliasServlet(self).register(resource)                    ProfileAvatarURLRestServlet(self).register(resource)                    ProfileDisplaynameRestServlet(self).register(resource)                    ProfileRestServlet(self).register(resource)                    KeyUploadServlet(self).register(resource)                    AccountDataServlet(self).register(resource)                    RoomAccountDataServlet(self).register(resource)                    RoomTypingRestServlet(self).register(resource)                    sync.register_servlets(self, resource)                    events.register_servlets(self, resource)                    InitialSyncRestServlet(self).register(resource)                    RoomInitialSyncRestServlet(self).register(resource)                    user_directory.register_servlets(self, resource)                    # If presence is disabled, use the stub servlet that does                    # not allow sending presence                    if not self.config.use_presence:                        PresenceStatusStubServlet(self).register(resource)                    groups.register_servlets(self, resource)                    resources.update({CLIENT_API_PREFIX: resource})                elif name == "federation":                    resources.update({FEDERATION_PREFIX: TransportLayerServer(self)})                elif name == "media":                    if self.config.can_load_media_repo:                        media_repo = self.get_media_repository_resource()                        # We need to serve the admin servlets for media on the                        # worker.                        admin_resource = JsonResource(self, canonical_json=False)                        register_servlets_for_media_repo(self, admin_resource)                        resources.update(                            {                                MEDIA_PREFIX: media_repo,                                LEGACY_MEDIA_PREFIX: media_repo,                                "/_synapse/admin": admin_resource,                            }                        )                    else:                        logger.warning(                            "A 'media' listener is configured but the media"                            " repository is disabled. Ignoring."                        )                if name == "openid" and "federation" not in res.names:                    # Only load the openid resource separately if federation resource                    # is not specified since federation resource includes openid                    # resource.                    resources.update(                        {                            FEDERATION_PREFIX: TransportLayerServer(                                self, servlet_groups=["openid"]                            )                        }                    )                if name in ["keys", "federation"]:                    resources[SERVER_KEY_V2_PREFIX] = KeyApiV2Resource(self)                if name == "replication":                    resources[REPLICATION_PREFIX] = ReplicationRestResource(self)        root_resource = create_resource_tree(resources, OptionsResource())        _base.listen_tcp(            bind_addresses,            port,            SynapseSite(                "synapse.access.http.%s" % (site_tag,),                site_tag,                listener_config,                root_resource,                self.version_string,            ),            reactor=self.get_reactor(),        )        logger.info("Synapse worker now listening on port %d", port)    def start_listening(self, listeners: Iterable[ListenerConfig]):        for listener in listeners:            if listener.type == "http":                self._listen_http(listener)            elif listener.type == "manhole":                _base.listen_tcp(                    listener.bind_addresses,                    listener.port,                    manhole(                        username="matrix", password="rabbithole", globals={"hs": self}                    ),                )            elif listener.type == "metrics":                if not self.get_config().enable_metrics:                    logger.warning(                        (                            "Metrics listener configured, but "                            "enable_metrics is not True!"                        )                    )                else:                    _base.listen_metrics(listener.bind_addresses, listener.port)            else:                logger.warning("Unsupported listener type: %s", listener.type)        self.get_tcp_replication().start_replication(self)    async def remove_pusher(self, app_id, push_key, user_id):        self.get_tcp_replication().send_remove_pusher(app_id, push_key, user_id)    @cache_in_self    def get_replication_data_handler(self):        return GenericWorkerReplicationHandler(self)    @cache_in_self    def get_presence_handler(self):        return GenericWorkerPresence(self)class GenericWorkerReplicationHandler(ReplicationDataHandler):    def __init__(self, hs):        super().__init__(hs)        self.store = hs.get_datastore()        self.presence_handler = hs.get_presence_handler()  # type: GenericWorkerPresence        self.notifier = hs.get_notifier()        self.notify_pushers = hs.config.start_pushers        self.pusher_pool = hs.get_pusherpool()        self.send_handler = None  # type: Optional[FederationSenderHandler]        if hs.config.send_federation:            self.send_handler = FederationSenderHandler(hs)    async def on_rdata(self, stream_name, instance_name, token, rows):        await super().on_rdata(stream_name, instance_name, token, rows)        await self._process_and_notify(stream_name, instance_name, token, rows)    async def _process_and_notify(self, stream_name, instance_name, token, rows):        try:            if self.send_handler:                await self.send_handler.process_replication_rows(                    stream_name, token, rows                )            if stream_name == PushRulesStream.NAME:                self.notifier.on_new_event(                    "push_rules_key", token, users=[row.user_id for row in rows]                )            elif stream_name in (AccountDataStream.NAME, TagAccountDataStream.NAME):                self.notifier.on_new_event(                    "account_data_key", token, users=[row.user_id for row in rows]                )            elif stream_name == ReceiptsStream.NAME:                self.notifier.on_new_event(                    "receipt_key", token, rooms=[row.room_id for row in rows]                )                await self.pusher_pool.on_new_receipts(                    token, token, {row.room_id for row in rows}                )            elif stream_name == ToDeviceStream.NAME:                entities = [row.entity for row in rows if row.entity.startswith("@")]                if entities:                    self.notifier.on_new_event("to_device_key", token, users=entities)            elif stream_name == DeviceListsStream.NAME:                all_room_ids = set()  # type: Set[str]                for row in rows:                    if row.entity.startswith("@"):                        room_ids = await self.store.get_rooms_for_user(row.entity)                        all_room_ids.update(room_ids)                self.notifier.on_new_event("device_list_key", token, rooms=all_room_ids)            elif stream_name == PresenceStream.NAME:                await self.presence_handler.process_replication_rows(token, rows)            elif stream_name == GroupServerStream.NAME:                self.notifier.on_new_event(                    "groups_key", token, users=[row.user_id for row in rows]                )            elif stream_name == PushersStream.NAME:                for row in rows:                    if row.deleted:                        self.stop_pusher(row.user_id, row.app_id, row.pushkey)                    else:                        await self.start_pusher(row.user_id, row.app_id, row.pushkey)        except Exception:            logger.exception("Error processing replication")    async def on_position(self, stream_name: str, instance_name: str, token: int):        await super().on_position(stream_name, instance_name, token)        # Also call on_rdata to ensure that stream positions are properly reset.        await self.on_rdata(stream_name, instance_name, token, [])    def stop_pusher(self, user_id, app_id, pushkey):        if not self.notify_pushers:            return        key = "%s:%s" % (app_id, pushkey)        pushers_for_user = self.pusher_pool.pushers.get(user_id, {})        pusher = pushers_for_user.pop(key, None)        if pusher is None:            return        logger.info("Stopping pusher %r / %r", user_id, key)        pusher.on_stop()    async def start_pusher(self, user_id, app_id, pushkey):        if not self.notify_pushers:            return        key = "%s:%s" % (app_id, pushkey)        logger.info("Starting pusher %r / %r", user_id, key)        return await self.pusher_pool.start_pusher_by_id(app_id, pushkey, user_id)    def on_remote_server_up(self, server: str):        """Called when get a new REMOTE_SERVER_UP command."""        # Let's wake up the transaction queue for the server in case we have        # pending stuff to send to it.        if self.send_handler:            self.send_handler.wake_destination(server)class FederationSenderHandler:    """Processes the fedration replication stream    This class is only instantiate on the worker responsible for sending outbound    federation transactions. It receives rows from the replication stream and forwards    the appropriate entries to the FederationSender class.    """    def __init__(self, hs: GenericWorkerServer):        self.store = hs.get_datastore()        self._is_mine_id = hs.is_mine_id        self.federation_sender = hs.get_federation_sender()        self._hs = hs        # Stores the latest position in the federation stream we've gotten up        # to. This is always set before we use it.        self.federation_position = None        self._fed_position_linearizer = Linearizer(name="_fed_position_linearizer")    def on_start(self):        # There may be some events that are persisted but haven't been sent,        # so send them now.        self.federation_sender.notify_new_events(            self.store.get_room_max_stream_ordering()        )    def wake_destination(self, server: str):        self.federation_sender.wake_destination(server)    async def process_replication_rows(self, stream_name, token, rows):        # The federation stream contains things that we want to send out, e.g.        # presence, typing, etc.        if stream_name == "federation":            send_queue.process_rows_for_federation(self.federation_sender, rows)            await self.update_token(token)        # ... and when new receipts happen        elif stream_name == ReceiptsStream.NAME:            await self._on_new_receipts(rows)        # ... as well as device updates and messages        elif stream_name == DeviceListsStream.NAME:            # The entities are either user IDs (starting with '@') whose devices            # have changed, or remote servers that we need to tell about            # changes.            hosts = {row.entity for row in rows if not row.entity.startswith("@")}            for host in hosts:                self.federation_sender.send_device_messages(host)        elif stream_name == ToDeviceStream.NAME:            # The to_device stream includes stuff to be pushed to both local            # clients and remote servers, so we ignore entities that start with            # '@' (since they'll be local users rather than destinations).            hosts = {row.entity for row in rows if not row.entity.startswith("@")}            for host in hosts:                self.federation_sender.send_device_messages(host)    async def _on_new_receipts(self, rows):        """        Args:            rows (Iterable[synapse.replication.tcp.streams.ReceiptsStream.ReceiptsStreamRow]):                new receipts to be processed        """        for receipt in rows:            # we only want to send on receipts for our own users            if not self._is_mine_id(receipt.user_id):                continue            receipt_info = ReadReceipt(                receipt.room_id,                receipt.receipt_type,                receipt.user_id,                [receipt.event_id],                receipt.data,            )            await self.federation_sender.send_read_receipt(receipt_info)    async def update_token(self, token):        """Update the record of where we have processed to in the federation stream.        Called after we have processed a an update received over replication. Sends        a FEDERATION_ACK back to the master, and stores the token that we have processed         in `federation_stream_position` so that we can restart where we left off.        """        self.federation_position = token        # We save and send the ACK to master asynchronously, so we don't block        # processing on persistence. We don't need to do this operation for        # every single RDATA we receive, we just need to do it periodically.        if self._fed_position_linearizer.is_queued(None):            # There is already a task queued up to save and send the token, so            # no need to queue up another task.            return        run_as_background_process("_save_and_send_ack", self._save_and_send_ack)    async def _save_and_send_ack(self):        """Save the current federation position in the database and send an ACK        to master with where we're up to.        """        try:            # We linearize here to ensure we don't have races updating the token            #            # XXX this appears to be redundant, since the ReplicationCommandHandler            # has a linearizer which ensures that we only process one line of            # replication data at a time. Should we remove it, or is it doing useful            # service for robustness? Or could we replace it with an assertion that            # we're not being re-entered?            with (await self._fed_position_linearizer.queue(None)):                # We persist and ack the same position, so we take a copy of it                # here as otherwise it can get modified from underneath us.                current_position = self.federation_position                await self.store.update_federation_out_pos(                    "federation", current_position                )                # We ACK this token over replication so that the master can drop                # its in memory queues                self._hs.get_tcp_replication().send_federation_ack(current_position)        except Exception:            logger.exception("Error updating federation stream position")def start(config_options):    try:        config = HomeServerConfig.load_config("Synapse worker", config_options)    except ConfigError as e:        sys.stderr.write("\n" + str(e) + "\n")        sys.exit(1)    # For backwards compatibility let any of the old app names.    assert config.worker_app in (        "synapse.app.appservice",        "synapse.app.client_reader",        "synapse.app.event_creator",        "synapse.app.federation_reader",        "synapse.app.federation_sender",        "synapse.app.frontend_proxy",        "synapse.app.generic_worker",        "synapse.app.media_repository",        "synapse.app.pusher",        "synapse.app.synchrotron",        "synapse.app.user_dir",    )    if config.worker_app == "synapse.app.appservice":        if config.appservice.notify_appservices:            sys.stderr.write(                "\nThe appservices must be disabled in the main synapse process"                "\nbefore they can be run in a separate worker."                "\nPlease add ``notify_appservices: false`` to the main config"                "\n"            )            sys.exit(1)        # Force the appservice to start since they will be disabled in the main config        config.appservice.notify_appservices = True    else:        # For other worker types we force this to off.        config.appservice.notify_appservices = False    if config.worker_app == "synapse.app.pusher":        if config.server.start_pushers:            sys.stderr.write(                "\nThe pushers must be disabled in the main synapse process"                "\nbefore they can be run in a separate worker."                "\nPlease add ``start_pushers: false`` to the main config"                "\n"            )            sys.exit(1)        # Force the pushers to start since they will be disabled in the main config        config.server.start_pushers = True    else:        # For other worker types we force this to off.        config.server.start_pushers = False    if config.worker_app == "synapse.app.user_dir":        if config.server.update_user_directory:            sys.stderr.write(                "\nThe update_user_directory must be disabled in the main synapse process"                "\nbefore they can be run in a separate worker."                "\nPlease add ``update_user_directory: false`` to the main config"                "\n"            )            sys.exit(1)        # Force the pushers to start since they will be disabled in the main config        config.server.update_user_directory = True    else:        # For other worker types we force this to off.        config.server.update_user_directory = False    if config.worker_app == "synapse.app.federation_sender":        if config.worker.send_federation:            sys.stderr.write(                "\nThe send_federation must be disabled in the main synapse process"                "\nbefore they can be run in a separate worker."                "\nPlease add ``send_federation: false`` to the main config"                "\n"            )            sys.exit(1)        # Force the pushers to start since they will be disabled in the main config        config.worker.send_federation = True    else:        # For other worker types we force this to off.        config.worker.send_federation = False    synapse.events.USE_FROZEN_DICTS = config.use_frozen_dicts    hs = GenericWorkerServer(        config.server_name,        config=config,        version_string="Synapse/" + get_version_string(synapse),    )    setup_logging(hs, config, use_worker_options=True)    hs.setup()    # Ensure the replication streamer is always started in case we write to any    # streams. Will no-op if no streams can be written to by this worker.    hs.get_replication_streamer()    reactor.addSystemEventTrigger(        "before", "startup", _base.start, hs, config.worker_listeners    )    _base.start_worker_reactor("synapse-generic-worker", config)if __name__ == "__main__":    with LoggingContext("main"):        start(sys.argv[1:])