dendrite/appservice/consumers/roomserver.go
Will Hunt a2773922d2
Send events to appservice based on room membership (#1680)
* Check membership of room

* Use QueryStateAfterEventsResponse

* Fix complexity

* Changes that I made a long time ago

* Rename to appserviceJoinedAtEvent

* Check membership in GetMemberships

* Update QueryMembershipsForRoom

* Tweaks in client API

* Update appserviceJoinedAtEvent

* Comments

* Try QueryMembershipForUser instead

* Undo some changes to client API that shouldn't be needed

* More /event tweaks

* Refactor /event bit

* Go back to QueryMembershipsForRoom because appservices are hard

* Fix bugs in onMessage

* Add comments

Co-authored-by: Neil Alexander <neilalexander@users.noreply.github.com>
2021-03-03 16:27:44 +00:00

201 lines
7.1 KiB
Go

// Copyright 2018 Vector Creations 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.
package consumers
import (
"context"
"encoding/json"
"github.com/matrix-org/dendrite/appservice/storage"
"github.com/matrix-org/dendrite/appservice/types"
"github.com/matrix-org/dendrite/internal"
"github.com/matrix-org/dendrite/roomserver/api"
"github.com/matrix-org/dendrite/setup/config"
"github.com/matrix-org/dendrite/setup/process"
"github.com/matrix-org/gomatrixserverlib"
"github.com/Shopify/sarama"
log "github.com/sirupsen/logrus"
)
// OutputRoomEventConsumer consumes events that originated in the room server.
type OutputRoomEventConsumer struct {
roomServerConsumer *internal.ContinualConsumer
asDB storage.Database
rsAPI api.RoomserverInternalAPI
serverName string
workerStates []types.ApplicationServiceWorkerState
}
// NewOutputRoomEventConsumer creates a new OutputRoomEventConsumer. Call
// Start() to begin consuming from room servers.
func NewOutputRoomEventConsumer(
process *process.ProcessContext,
cfg *config.Dendrite,
kafkaConsumer sarama.Consumer,
appserviceDB storage.Database,
rsAPI api.RoomserverInternalAPI,
workerStates []types.ApplicationServiceWorkerState,
) *OutputRoomEventConsumer {
consumer := internal.ContinualConsumer{
Process: process,
ComponentName: "appservice/roomserver",
Topic: cfg.Global.Kafka.TopicFor(config.TopicOutputRoomEvent),
Consumer: kafkaConsumer,
PartitionStore: appserviceDB,
}
s := &OutputRoomEventConsumer{
roomServerConsumer: &consumer,
asDB: appserviceDB,
rsAPI: rsAPI,
serverName: string(cfg.Global.ServerName),
workerStates: workerStates,
}
consumer.ProcessMessage = s.onMessage
return s
}
// Start consuming from room servers
func (s *OutputRoomEventConsumer) Start() error {
return s.roomServerConsumer.Start()
}
// onMessage is called when the appservice component receives a new event from
// the room server output log.
func (s *OutputRoomEventConsumer) onMessage(msg *sarama.ConsumerMessage) error {
// Parse out the event JSON
var output api.OutputEvent
if err := json.Unmarshal(msg.Value, &output); err != nil {
// If the message was invalid, log it and move on to the next message in the stream
log.WithError(err).Errorf("roomserver output log: message parse failure")
return nil
}
if output.Type != api.OutputTypeNewRoomEvent {
return nil
}
events := []*gomatrixserverlib.HeaderedEvent{output.NewRoomEvent.Event}
events = append(events, output.NewRoomEvent.AddStateEvents...)
// Send event to any relevant application services
return s.filterRoomserverEvents(context.TODO(), events)
}
// filterRoomserverEvents takes in events and decides whether any of them need
// to be passed on to an external application service. It does this by checking
// each namespace of each registered application service, and if there is a
// match, adds the event to the queue for events to be sent to a particular
// application service.
func (s *OutputRoomEventConsumer) filterRoomserverEvents(
ctx context.Context,
events []*gomatrixserverlib.HeaderedEvent,
) error {
for _, ws := range s.workerStates {
for _, event := range events {
// Check if this event is interesting to this application service
if s.appserviceIsInterestedInEvent(ctx, event, ws.AppService) {
// Queue this event to be sent off to the application service
if err := s.asDB.StoreEvent(ctx, ws.AppService.ID, event); err != nil {
log.WithError(err).Warn("failed to insert incoming event into appservices database")
return err
} else {
// Tell our worker to send out new messages by updating remaining message
// count and waking them up with a broadcast
ws.NotifyNewEvents()
}
}
}
}
return nil
}
// appserviceJoinedAtEvent returns a boolean depending on whether a given
// appservice has membership at the time a given event was created.
func (s *OutputRoomEventConsumer) appserviceJoinedAtEvent(ctx context.Context, event *gomatrixserverlib.HeaderedEvent, appservice config.ApplicationService) bool {
// TODO: This is only checking the current room state, not the state at
// the event in question. Pretty sure this is what Synapse does too, but
// until we have a lighter way of checking the state before the event that
// doesn't involve state res, then this is probably OK.
membershipReq := &api.QueryMembershipsForRoomRequest{
RoomID: event.RoomID(),
JoinedOnly: true,
}
membershipRes := &api.QueryMembershipsForRoomResponse{}
// XXX: This could potentially race if the state for the event is not known yet
// e.g. the event came over federation but we do not have the full state persisted.
if err := s.rsAPI.QueryMembershipsForRoom(ctx, membershipReq, membershipRes); err == nil {
for _, ev := range membershipRes.JoinEvents {
var membership gomatrixserverlib.MemberContent
if err = json.Unmarshal(ev.Content, &membership); err != nil || ev.StateKey == nil {
continue
}
if appservice.IsInterestedInUserID(*ev.StateKey) {
return true
}
}
} else {
log.WithFields(log.Fields{
"room_id": event.RoomID(),
}).WithError(err).Errorf("Unable to get membership for room")
}
return false
}
// appserviceIsInterestedInEvent returns a boolean depending on whether a given
// event falls within one of a given application service's namespaces.
//
// TODO: This should be cached, see https://github.com/matrix-org/dendrite/issues/1682
func (s *OutputRoomEventConsumer) appserviceIsInterestedInEvent(ctx context.Context, event *gomatrixserverlib.HeaderedEvent, appservice config.ApplicationService) bool {
// No reason to queue events if they'll never be sent to the application
// service
if appservice.URL == "" {
return false
}
// Check Room ID and Sender of the event
if appservice.IsInterestedInUserID(event.Sender()) ||
appservice.IsInterestedInRoomID(event.RoomID()) {
return true
}
if event.Type() == gomatrixserverlib.MRoomMember && event.StateKey() != nil {
if appservice.IsInterestedInUserID(*event.StateKey()) {
return true
}
}
// Check all known room aliases of the room the event came from
queryReq := api.GetAliasesForRoomIDRequest{RoomID: event.RoomID()}
var queryRes api.GetAliasesForRoomIDResponse
if err := s.rsAPI.GetAliasesForRoomID(ctx, &queryReq, &queryRes); err == nil {
for _, alias := range queryRes.Aliases {
if appservice.IsInterestedInRoomAlias(alias) {
return true
}
}
} else {
log.WithFields(log.Fields{
"room_id": event.RoomID(),
}).WithError(err).Errorf("Unable to get aliases for room")
}
// Check if any of the members in the room match the appservice
return s.appserviceJoinedAtEvent(ctx, event, appservice)
}