dendrite/syncapi/consumers/keychange.go
Kegsay 9a5fb489c5
Add QueryKeyChanges (#1228)
Hook some things up to call it as well.
2020-07-28 18:25:16 +01:00

315 lines
11 KiB
Go

// 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.
package consumers
import (
"context"
"encoding/json"
"sync"
"github.com/Shopify/sarama"
currentstateAPI "github.com/matrix-org/dendrite/currentstateserver/api"
"github.com/matrix-org/dendrite/internal"
"github.com/matrix-org/dendrite/keyserver/api"
"github.com/matrix-org/dendrite/syncapi/storage"
"github.com/matrix-org/dendrite/syncapi/types"
"github.com/matrix-org/gomatrixserverlib"
"github.com/matrix-org/util"
log "github.com/sirupsen/logrus"
)
// OutputKeyChangeEventConsumer consumes events that originated in the key server.
type OutputKeyChangeEventConsumer struct {
keyChangeConsumer *internal.ContinualConsumer
db storage.Database
serverName gomatrixserverlib.ServerName // our server name
currentStateAPI currentstateAPI.CurrentStateInternalAPI
keyAPI api.KeyInternalAPI
partitionToOffset map[int32]int64
partitionToOffsetMu sync.Mutex
}
// NewOutputKeyChangeEventConsumer creates a new OutputKeyChangeEventConsumer.
// Call Start() to begin consuming from the key server.
func NewOutputKeyChangeEventConsumer(
serverName gomatrixserverlib.ServerName,
topic string,
kafkaConsumer sarama.Consumer,
keyAPI api.KeyInternalAPI,
currentStateAPI currentstateAPI.CurrentStateInternalAPI,
store storage.Database,
) *OutputKeyChangeEventConsumer {
consumer := internal.ContinualConsumer{
Topic: topic,
Consumer: kafkaConsumer,
PartitionStore: store,
}
s := &OutputKeyChangeEventConsumer{
keyChangeConsumer: &consumer,
db: store,
serverName: serverName,
keyAPI: keyAPI,
currentStateAPI: currentStateAPI,
partitionToOffset: make(map[int32]int64),
partitionToOffsetMu: sync.Mutex{},
}
consumer.ProcessMessage = s.onMessage
return s
}
// Start consuming from the key server
func (s *OutputKeyChangeEventConsumer) Start() error {
offsets, err := s.keyChangeConsumer.StartOffsets()
s.partitionToOffsetMu.Lock()
for _, o := range offsets {
s.partitionToOffset[o.Partition] = o.Offset
}
s.partitionToOffsetMu.Unlock()
return err
}
func (s *OutputKeyChangeEventConsumer) updateOffset(msg *sarama.ConsumerMessage) {
s.partitionToOffsetMu.Lock()
defer s.partitionToOffsetMu.Unlock()
s.partitionToOffset[msg.Partition] = msg.Offset
}
func (s *OutputKeyChangeEventConsumer) onMessage(msg *sarama.ConsumerMessage) error {
defer func() {
s.updateOffset(msg)
}()
var output api.DeviceKeys
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).Error("syncapi: failed to unmarshal key change event from key server")
return err
}
// work out who we need to notify about the new key
var queryRes currentstateAPI.QuerySharedUsersResponse
err := s.currentStateAPI.QuerySharedUsers(context.Background(), &currentstateAPI.QuerySharedUsersRequest{
UserID: output.UserID,
}, &queryRes)
if err != nil {
log.WithError(err).Error("syncapi: failed to QuerySharedUsers for key change event from key server")
return err
}
// TODO: f.e queryRes.UserIDsToCount : notify users by waking up streams
return nil
}
// Catchup fills in the given response for the given user ID to bring it up-to-date with device lists. hasNew=true if the response
// was filled in, else false if there are no new device list changes because there is nothing to catch up on. The response MUST
// be already filled in with join/leave information.
func (s *OutputKeyChangeEventConsumer) Catchup(
ctx context.Context, userID string, res *types.Response, tok types.StreamingToken,
) (newTok *types.StreamingToken, hasNew bool, err error) {
// Track users who we didn't track before but now do by virtue of sharing a room with them, or not.
newlyJoinedRooms := joinedRooms(res, userID)
newlyLeftRooms := leftRooms(res)
if len(newlyJoinedRooms) > 0 || len(newlyLeftRooms) > 0 {
changed, left, err := s.trackChangedUsers(ctx, userID, newlyJoinedRooms, newlyLeftRooms)
if err != nil {
return nil, false, err
}
res.DeviceLists.Changed = changed
res.DeviceLists.Left = left
hasNew = len(changed) > 0 || len(left) > 0
}
// now also track users who we already share rooms with but who have updated their devices between the two tokens
// TODO: Extract partition/offset from sync token
var partition int32
var offset int64
var queryRes api.QueryKeyChangesResponse
s.keyAPI.QueryKeyChanges(ctx, &api.QueryKeyChangesRequest{
Partition: partition,
Offset: offset,
}, &queryRes)
if queryRes.Error != nil {
// don't fail the catchup because we may have got useful information by tracking membership
util.GetLogger(ctx).WithError(queryRes.Error).Error("QueryKeyChanges failed")
} else {
// TODO: Make a new streaming token using the new offset
userSet := make(map[string]bool)
for _, userID := range res.DeviceLists.Changed {
userSet[userID] = true
}
for _, userID := range queryRes.UserIDs {
if !userSet[userID] {
res.DeviceLists.Changed = append(res.DeviceLists.Changed, userID)
}
}
}
return
}
func (s *OutputKeyChangeEventConsumer) OnJoinEvent(ev *gomatrixserverlib.HeaderedEvent) {
// work out who we are now sharing rooms with which we previously were not and notify them about the joining
// users keys:
changed, _, err := s.trackChangedUsers(context.Background(), *ev.StateKey(), []string{ev.RoomID()}, nil)
if err != nil {
log.WithError(err).Error("OnJoinEvent: failed to work out changed users")
return
}
// TODO: f.e changed, wake up stream
for _, userID := range changed {
log.Infof("OnJoinEvent:Notify %s that %s should have device lists tracked", userID, *ev.StateKey())
}
}
func (s *OutputKeyChangeEventConsumer) OnLeaveEvent(ev *gomatrixserverlib.HeaderedEvent) {
// work out who we are no longer sharing any rooms with and notify them about the leaving user
_, left, err := s.trackChangedUsers(context.Background(), *ev.StateKey(), nil, []string{ev.RoomID()})
if err != nil {
log.WithError(err).Error("OnLeaveEvent: failed to work out left users")
return
}
// TODO: f.e left, wake up stream
for _, userID := range left {
log.Infof("OnLeaveEvent:Notify %s that %s should no longer track device lists", userID, *ev.StateKey())
}
}
// nolint:gocyclo
func (s *OutputKeyChangeEventConsumer) trackChangedUsers(
ctx context.Context, userID string, newlyJoinedRooms, newlyLeftRooms []string,
) (changed, left []string, err error) {
// process leaves first, then joins afterwards so if we join/leave/join/leave we err on the side of including users.
// Leave algorithm:
// - Get set of users and number of times they appear in rooms prior to leave. - QuerySharedUsersRequest with 'IncludeRoomID'.
// - Get users in newly left room. - QueryCurrentState
// - Loop set of users and decrement by 1 for each user in newly left room.
// - If count=0 then they share no more rooms so inform BOTH parties of this via 'left'=[...] in /sync.
var queryRes currentstateAPI.QuerySharedUsersResponse
err = s.currentStateAPI.QuerySharedUsers(ctx, &currentstateAPI.QuerySharedUsersRequest{
UserID: userID,
IncludeRoomIDs: newlyLeftRooms,
}, &queryRes)
if err != nil {
return nil, nil, err
}
var stateRes currentstateAPI.QueryBulkStateContentResponse
err = s.currentStateAPI.QueryBulkStateContent(ctx, &currentstateAPI.QueryBulkStateContentRequest{
RoomIDs: newlyLeftRooms,
StateTuples: []gomatrixserverlib.StateKeyTuple{
{
EventType: gomatrixserverlib.MRoomMember,
StateKey: "*",
},
},
AllowWildcards: true,
}, &stateRes)
if err != nil {
return nil, nil, err
}
for _, state := range stateRes.Rooms {
for tuple, membership := range state {
if membership != gomatrixserverlib.Join {
continue
}
queryRes.UserIDsToCount[tuple.StateKey]--
}
}
for userID, count := range queryRes.UserIDsToCount {
if count <= 0 {
left = append(left, userID) // left is returned
}
}
// Join algorithm:
// - Get the set of all joined users prior to joining room - QuerySharedUsersRequest with 'ExcludeRoomID'.
// - Get users in newly joined room - QueryCurrentState
// - Loop set of users in newly joined room, do they appear in the set of users prior to joining?
// - If yes: then they already shared a room in common, do nothing.
// - If no: then they are a brand new user so inform BOTH parties of this via 'changed=[...]'
err = s.currentStateAPI.QuerySharedUsers(ctx, &currentstateAPI.QuerySharedUsersRequest{
UserID: userID,
ExcludeRoomIDs: newlyJoinedRooms,
}, &queryRes)
if err != nil {
return nil, left, err
}
err = s.currentStateAPI.QueryBulkStateContent(ctx, &currentstateAPI.QueryBulkStateContentRequest{
RoomIDs: newlyJoinedRooms,
StateTuples: []gomatrixserverlib.StateKeyTuple{
{
EventType: gomatrixserverlib.MRoomMember,
StateKey: "*",
},
},
AllowWildcards: true,
}, &stateRes)
if err != nil {
return nil, left, err
}
for _, state := range stateRes.Rooms {
for tuple, membership := range state {
if membership != gomatrixserverlib.Join {
continue
}
// new user who we weren't previously sharing rooms with
if _, ok := queryRes.UserIDsToCount[tuple.StateKey]; !ok {
changed = append(changed, tuple.StateKey) // changed is returned
}
}
}
return changed, left, nil
}
func joinedRooms(res *types.Response, userID string) []string {
var roomIDs []string
for roomID, join := range res.Rooms.Join {
// we would expect to see our join event somewhere if we newly joined the room.
// Normal events get put in the join section so it's not enough to know the room ID is present in 'join'.
newlyJoined := membershipEventPresent(join.State.Events, userID)
if newlyJoined {
roomIDs = append(roomIDs, roomID)
continue
}
newlyJoined = membershipEventPresent(join.Timeline.Events, userID)
if newlyJoined {
roomIDs = append(roomIDs, roomID)
}
}
return roomIDs
}
func leftRooms(res *types.Response) []string {
roomIDs := make([]string, len(res.Rooms.Leave))
i := 0
for roomID := range res.Rooms.Leave {
roomIDs[i] = roomID
i++
}
return roomIDs
}
func membershipEventPresent(events []gomatrixserverlib.ClientEvent, userID string) bool {
for _, ev := range events {
// it's enough to know that we have our member event here, don't need to check membership content
// as it's implied by being in the respective section of the sync response.
if ev.Type == gomatrixserverlib.MRoomMember && ev.StateKey != nil && *ev.StateKey == userID {
return true
}
}
return false
}