443 lines
16 KiB
Go
443 lines
16 KiB
Go
// Copyright 2017 Vector Creations Ltd
|
|
// Copyright 2018 New Vector Ltd
|
|
// Copyright 2019-2020 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 input
|
|
|
|
import (
|
|
"context"
|
|
"fmt"
|
|
|
|
"github.com/getsentry/sentry-go"
|
|
"github.com/matrix-org/gomatrixserverlib"
|
|
"github.com/matrix-org/util"
|
|
"github.com/sirupsen/logrus"
|
|
|
|
"github.com/matrix-org/dendrite/internal"
|
|
"github.com/matrix-org/dendrite/internal/sqlutil"
|
|
"github.com/matrix-org/dendrite/roomserver/api"
|
|
"github.com/matrix-org/dendrite/roomserver/state"
|
|
"github.com/matrix-org/dendrite/roomserver/storage/shared"
|
|
"github.com/matrix-org/dendrite/roomserver/types"
|
|
)
|
|
|
|
// updateLatestEvents updates the list of latest events for this room in the database and writes the
|
|
// event to the output log.
|
|
// The latest events are the events that aren't referenced by another event in the database:
|
|
//
|
|
// Time goes down the page. 1 is the m.room.create event (root).
|
|
// 1 After storing 1 the latest events are {1}
|
|
// | After storing 2 the latest events are {2}
|
|
// 2 After storing 3 the latest events are {3}
|
|
// / \ After storing 4 the latest events are {3,4}
|
|
// 3 4 After storing 5 the latest events are {5,4}
|
|
// | | After storing 6 the latest events are {5,6}
|
|
// 5 6 <--- latest After storing 7 the latest events are {6,7}
|
|
// |
|
|
// 7 <----- latest
|
|
//
|
|
// Can only be called once at a time
|
|
func (r *Inputer) updateLatestEvents(
|
|
ctx context.Context,
|
|
roomInfo *types.RoomInfo,
|
|
stateAtEvent types.StateAtEvent,
|
|
event gomatrixserverlib.PDU,
|
|
sendAsServer string,
|
|
transactionID *api.TransactionID,
|
|
rewritesState bool,
|
|
historyVisibility gomatrixserverlib.HistoryVisibility,
|
|
) (err error) {
|
|
trace, ctx := internal.StartRegion(ctx, "updateLatestEvents")
|
|
defer trace.EndRegion()
|
|
|
|
var succeeded bool
|
|
updater, err := r.DB.GetRoomUpdater(ctx, roomInfo)
|
|
if err != nil {
|
|
return fmt.Errorf("r.DB.GetRoomUpdater: %w", err)
|
|
}
|
|
|
|
defer sqlutil.EndTransactionWithCheck(updater, &succeeded, &err)
|
|
|
|
u := latestEventsUpdater{
|
|
ctx: ctx,
|
|
api: r,
|
|
updater: updater,
|
|
roomInfo: roomInfo,
|
|
stateAtEvent: stateAtEvent,
|
|
event: event,
|
|
sendAsServer: sendAsServer,
|
|
transactionID: transactionID,
|
|
rewritesState: rewritesState,
|
|
historyVisibility: historyVisibility,
|
|
}
|
|
|
|
if err = u.doUpdateLatestEvents(); err != nil {
|
|
return fmt.Errorf("u.doUpdateLatestEvents: %w", err)
|
|
}
|
|
|
|
succeeded = true
|
|
return
|
|
}
|
|
|
|
// latestEventsUpdater tracks the state used to update the latest events in the
|
|
// room. It mostly just ferries state between the various function calls.
|
|
// The state could be passed using function arguments, but it becomes impractical
|
|
// when there are so many variables to pass around.
|
|
type latestEventsUpdater struct {
|
|
ctx context.Context
|
|
api *Inputer
|
|
updater *shared.RoomUpdater
|
|
roomInfo *types.RoomInfo
|
|
stateAtEvent types.StateAtEvent
|
|
event gomatrixserverlib.PDU
|
|
transactionID *api.TransactionID
|
|
rewritesState bool
|
|
// Which server to send this event as.
|
|
sendAsServer string
|
|
// The eventID of the event that was processed before this one.
|
|
lastEventIDSent string
|
|
// The latest events in the room after processing this event.
|
|
oldLatest types.StateAtEventAndReferences
|
|
latest types.StateAtEventAndReferences
|
|
// The state entries removed from and added to the current state of the
|
|
// room as a result of processing this event. They are sorted lists.
|
|
removed []types.StateEntry
|
|
added []types.StateEntry
|
|
// The state entries that are removed and added to recover the state before
|
|
// the event being processed. They are sorted lists.
|
|
stateBeforeEventRemoves []types.StateEntry
|
|
stateBeforeEventAdds []types.StateEntry
|
|
// The snapshots of current state before and after processing this event
|
|
oldStateNID types.StateSnapshotNID
|
|
newStateNID types.StateSnapshotNID
|
|
// The history visibility of the event itself (from the state before the event).
|
|
historyVisibility gomatrixserverlib.HistoryVisibility
|
|
}
|
|
|
|
func (u *latestEventsUpdater) doUpdateLatestEvents() error {
|
|
u.lastEventIDSent = u.updater.LastEventIDSent()
|
|
|
|
// If we are doing a regular event update then we will get the
|
|
// previous latest events to use as a part of the calculation. If
|
|
// we are overwriting the latest events because we have a complete
|
|
// state snapshot from somewhere else, e.g. a federated room join,
|
|
// then start with an empty set - none of the forward extremities
|
|
// that we knew about before matter anymore.
|
|
u.oldLatest = types.StateAtEventAndReferences{}
|
|
if !u.rewritesState {
|
|
u.oldStateNID = u.updater.CurrentStateSnapshotNID()
|
|
u.oldLatest = u.updater.LatestEvents()
|
|
}
|
|
|
|
// If the event has already been written to the output log then we
|
|
// don't need to do anything, as we've handled it already.
|
|
if hasBeenSent, err := u.updater.HasEventBeenSent(u.stateAtEvent.EventNID); err != nil {
|
|
return fmt.Errorf("u.updater.HasEventBeenSent: %w", err)
|
|
} else if hasBeenSent {
|
|
return nil
|
|
}
|
|
|
|
// Work out what the latest events are. This will include the new
|
|
// event if it is not already referenced.
|
|
extremitiesChanged, err := u.calculateLatest(
|
|
u.oldLatest, u.event,
|
|
types.StateAtEventAndReference{
|
|
EventID: u.event.EventID(),
|
|
StateAtEvent: u.stateAtEvent,
|
|
},
|
|
)
|
|
if err != nil {
|
|
return fmt.Errorf("u.calculateLatest: %w", err)
|
|
}
|
|
|
|
// Now that we know what the latest events are, it's time to get the
|
|
// latest state.
|
|
var updates []api.OutputEvent
|
|
if extremitiesChanged || u.rewritesState {
|
|
if err = u.latestState(); err != nil {
|
|
return fmt.Errorf("u.latestState: %w", err)
|
|
}
|
|
|
|
// If we need to generate any output events then here's where we do it.
|
|
// TODO: Move this!
|
|
if updates, err = u.api.updateMemberships(u.ctx, u.updater, u.removed, u.added); err != nil {
|
|
return fmt.Errorf("u.api.updateMemberships: %w", err)
|
|
}
|
|
} else {
|
|
u.newStateNID = u.oldStateNID
|
|
}
|
|
|
|
if err = u.updater.SetLatestEvents(u.roomInfo.RoomNID, u.latest, u.stateAtEvent.EventNID, u.newStateNID); err != nil {
|
|
return fmt.Errorf("u.updater.SetLatestEvents: %w", err)
|
|
}
|
|
|
|
update, err := u.makeOutputNewRoomEvent()
|
|
if err != nil {
|
|
return fmt.Errorf("u.makeOutputNewRoomEvent: %w", err)
|
|
}
|
|
updates = append(updates, *update)
|
|
|
|
// Send the event to the output logs.
|
|
// We do this inside the database transaction to ensure that we only mark an event as sent if we sent it.
|
|
// (n.b. this means that it's possible that the same event will be sent twice if the transaction fails but
|
|
// the write to the output log succeeds)
|
|
// TODO: This assumes that writing the event to the output log is synchronous. It should be possible to
|
|
// send the event asynchronously but we would need to ensure that 1) the events are written to the log in
|
|
// the correct order, 2) that pending writes are resent across restarts. In order to avoid writing all the
|
|
// necessary bookkeeping we'll keep the event sending synchronous for now.
|
|
if err = u.api.OutputProducer.ProduceRoomEvents(u.event.RoomID().String(), updates); err != nil {
|
|
return fmt.Errorf("u.api.WriteOutputEvents: %w", err)
|
|
}
|
|
|
|
if err = u.updater.MarkEventAsSent(u.stateAtEvent.EventNID); err != nil {
|
|
return fmt.Errorf("u.updater.MarkEventAsSent: %w", err)
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
func (u *latestEventsUpdater) latestState() error {
|
|
trace, ctx := internal.StartRegion(u.ctx, "processEventWithMissingState")
|
|
defer trace.EndRegion()
|
|
|
|
var err error
|
|
roomState := state.NewStateResolution(u.updater, u.roomInfo, u.api.Queryer)
|
|
|
|
// Work out if the state at the extremities has actually changed
|
|
// or not. If they haven't then we won't bother doing all of the
|
|
// hard work.
|
|
if !u.stateAtEvent.IsStateEvent() {
|
|
stateChanged := false
|
|
oldStateNIDs := make([]types.StateSnapshotNID, 0, len(u.oldLatest))
|
|
newStateNIDs := make([]types.StateSnapshotNID, 0, len(u.latest))
|
|
for _, old := range u.oldLatest {
|
|
oldStateNIDs = append(oldStateNIDs, old.BeforeStateSnapshotNID)
|
|
}
|
|
for _, new := range u.latest {
|
|
newStateNIDs = append(newStateNIDs, new.BeforeStateSnapshotNID)
|
|
}
|
|
oldStateNIDs = state.UniqueStateSnapshotNIDs(oldStateNIDs)
|
|
newStateNIDs = state.UniqueStateSnapshotNIDs(newStateNIDs)
|
|
if len(oldStateNIDs) != len(newStateNIDs) {
|
|
stateChanged = true
|
|
} else {
|
|
for i := range oldStateNIDs {
|
|
if oldStateNIDs[i] != newStateNIDs[i] {
|
|
stateChanged = true
|
|
break
|
|
}
|
|
}
|
|
}
|
|
if !stateChanged {
|
|
u.newStateNID = u.oldStateNID
|
|
return nil
|
|
}
|
|
}
|
|
|
|
// Get a list of the current latest events. This may or may not
|
|
// include the new event from the input path, depending on whether
|
|
// it is a forward extremity or not.
|
|
latestStateAtEvents := make([]types.StateAtEvent, len(u.latest))
|
|
for i := range u.latest {
|
|
latestStateAtEvents[i] = u.latest[i].StateAtEvent
|
|
}
|
|
|
|
// Takes the NIDs of the latest events and creates a state snapshot
|
|
// of the state after the events. The snapshot state will be resolved
|
|
// using the correct state resolution algorithm for the room.
|
|
u.newStateNID, err = roomState.CalculateAndStoreStateAfterEvents(
|
|
ctx, latestStateAtEvents,
|
|
)
|
|
if err != nil {
|
|
return fmt.Errorf("roomState.CalculateAndStoreStateAfterEvents: %w", err)
|
|
}
|
|
|
|
// Include information about what changed in the state transition. If the
|
|
// event rewrites the state (i.e. is a federated join) then we will simply
|
|
// include the entire state snapshot as added events, as the "RewritesState"
|
|
// flag in the output event signals downstream components to purge their
|
|
// room state first. If it doesn't rewrite the state then we will work out
|
|
// what the difference is between the state snapshots and send that. In all
|
|
// cases where a state event is being replaced, the old state event will
|
|
// appear in "removed" and the replacement will appear in "added".
|
|
if u.rewritesState {
|
|
u.removed = []types.StateEntry{}
|
|
u.added, err = roomState.LoadStateAtSnapshot(ctx, u.newStateNID)
|
|
if err != nil {
|
|
return fmt.Errorf("roomState.LoadStateAtSnapshot: %w", err)
|
|
}
|
|
} else {
|
|
u.removed, u.added, err = roomState.DifferenceBetweeenStateSnapshots(
|
|
ctx, u.oldStateNID, u.newStateNID,
|
|
)
|
|
if err != nil {
|
|
return fmt.Errorf("roomState.DifferenceBetweenStateSnapshots: %w", err)
|
|
}
|
|
}
|
|
|
|
if removed := len(u.removed) - len(u.added); !u.rewritesState && removed > 0 {
|
|
logrus.WithFields(logrus.Fields{
|
|
"event_id": u.event.EventID(),
|
|
"room_id": u.event.RoomID().String(),
|
|
"old_state_nid": u.oldStateNID,
|
|
"new_state_nid": u.newStateNID,
|
|
"old_latest": u.oldLatest.EventIDs(),
|
|
"new_latest": u.latest.EventIDs(),
|
|
}).Warnf("State reset detected (removing %d events)", removed)
|
|
sentry.WithScope(func(scope *sentry.Scope) {
|
|
scope.SetLevel("warning")
|
|
scope.SetContext("State reset", map[string]interface{}{
|
|
"Event ID": u.event.EventID(),
|
|
"Old state NID": fmt.Sprintf("%d", u.oldStateNID),
|
|
"New state NID": fmt.Sprintf("%d", u.newStateNID),
|
|
"Old latest": u.oldLatest.EventIDs(),
|
|
"New latest": u.latest.EventIDs(),
|
|
"State removed": removed,
|
|
})
|
|
sentry.CaptureMessage("State reset detected")
|
|
})
|
|
}
|
|
|
|
// Also work out the state before the event removes and the event
|
|
// adds.
|
|
u.stateBeforeEventRemoves, u.stateBeforeEventAdds, err = roomState.DifferenceBetweeenStateSnapshots(
|
|
ctx, u.newStateNID, u.stateAtEvent.BeforeStateSnapshotNID,
|
|
)
|
|
if err != nil {
|
|
return fmt.Errorf("roomState.DifferenceBetweeenStateSnapshots: %w", err)
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
// calculateLatest works out the new set of forward extremities. Returns
|
|
// true if the new event is included in those extremites, false otherwise.
|
|
func (u *latestEventsUpdater) calculateLatest(
|
|
oldLatest []types.StateAtEventAndReference,
|
|
newEvent gomatrixserverlib.PDU,
|
|
newStateAndRef types.StateAtEventAndReference,
|
|
) (bool, error) {
|
|
trace, _ := internal.StartRegion(u.ctx, "calculateLatest")
|
|
defer trace.EndRegion()
|
|
|
|
// First of all, get a list of all of the events in our current
|
|
// set of forward extremities.
|
|
existingRefs := make(map[string]*types.StateAtEventAndReference)
|
|
for i, old := range oldLatest {
|
|
existingRefs[old.EventID] = &oldLatest[i]
|
|
}
|
|
|
|
// If the "new" event is already a forward extremity then stop, as
|
|
// nothing changes.
|
|
if _, ok := existingRefs[newEvent.EventID()]; ok {
|
|
u.latest = oldLatest
|
|
return false, nil
|
|
}
|
|
|
|
// If the "new" event is already referenced by an existing event
|
|
// then do nothing - it's not a candidate to be a new extremity if
|
|
// it has been referenced.
|
|
if referenced, err := u.updater.IsReferenced(newEvent.EventID()); err != nil {
|
|
return false, fmt.Errorf("u.updater.IsReferenced(new): %w", err)
|
|
} else if referenced {
|
|
u.latest = oldLatest
|
|
return false, nil
|
|
}
|
|
|
|
// Then let's see if any of the existing forward extremities now
|
|
// have entries in the previous events table. If they do then we
|
|
// will no longer include them as forward extremities.
|
|
for k, l := range existingRefs {
|
|
referenced, err := u.updater.IsReferenced(l.EventID)
|
|
if err != nil {
|
|
return false, fmt.Errorf("u.updater.IsReferenced: %w", err)
|
|
} else if referenced {
|
|
delete(existingRefs, k)
|
|
}
|
|
}
|
|
|
|
// Start off with our new unreferenced event. We're reusing the backing
|
|
// array here rather than allocating a new one.
|
|
u.latest = append(u.latest[:0], newStateAndRef)
|
|
|
|
// If our new event references any of the existing forward extremities
|
|
// then they are no longer forward extremities, so remove them.
|
|
for _, prevEventID := range newEvent.PrevEventIDs() {
|
|
delete(existingRefs, prevEventID)
|
|
}
|
|
|
|
// Then re-add any old extremities that are still valid after all.
|
|
for _, old := range existingRefs {
|
|
u.latest = append(u.latest, *old)
|
|
}
|
|
|
|
return true, nil
|
|
}
|
|
|
|
func (u *latestEventsUpdater) makeOutputNewRoomEvent() (*api.OutputEvent, error) {
|
|
latestEventIDs := make([]string, len(u.latest))
|
|
for i := range u.latest {
|
|
latestEventIDs[i] = u.latest[i].EventID
|
|
}
|
|
|
|
ore := api.OutputNewRoomEvent{
|
|
Event: &types.HeaderedEvent{PDU: u.event},
|
|
RewritesState: u.rewritesState,
|
|
LastSentEventID: u.lastEventIDSent,
|
|
LatestEventIDs: latestEventIDs,
|
|
TransactionID: u.transactionID,
|
|
SendAsServer: u.sendAsServer,
|
|
HistoryVisibility: u.historyVisibility,
|
|
}
|
|
|
|
eventIDMap, err := u.stateEventMap()
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
for _, entry := range u.added {
|
|
ore.AddsStateEventIDs = append(ore.AddsStateEventIDs, eventIDMap[entry.EventNID])
|
|
}
|
|
for _, entry := range u.removed {
|
|
ore.RemovesStateEventIDs = append(ore.RemovesStateEventIDs, eventIDMap[entry.EventNID])
|
|
}
|
|
for _, entry := range u.stateBeforeEventRemoves {
|
|
ore.StateBeforeRemovesEventIDs = append(ore.StateBeforeRemovesEventIDs, eventIDMap[entry.EventNID])
|
|
}
|
|
for _, entry := range u.stateBeforeEventAdds {
|
|
ore.StateBeforeAddsEventIDs = append(ore.StateBeforeAddsEventIDs, eventIDMap[entry.EventNID])
|
|
}
|
|
|
|
return &api.OutputEvent{
|
|
Type: api.OutputTypeNewRoomEvent,
|
|
NewRoomEvent: &ore,
|
|
}, nil
|
|
}
|
|
|
|
// retrieve an event nid -> event ID map for all events that need updating
|
|
func (u *latestEventsUpdater) stateEventMap() (map[types.EventNID]string, error) {
|
|
cap := len(u.added) + len(u.removed) + len(u.stateBeforeEventRemoves) + len(u.stateBeforeEventAdds)
|
|
stateEventNIDs := make(types.EventNIDs, 0, cap)
|
|
allStateEntries := make([]types.StateEntry, 0, cap)
|
|
allStateEntries = append(allStateEntries, u.added...)
|
|
allStateEntries = append(allStateEntries, u.removed...)
|
|
allStateEntries = append(allStateEntries, u.stateBeforeEventRemoves...)
|
|
allStateEntries = append(allStateEntries, u.stateBeforeEventAdds...)
|
|
for _, entry := range allStateEntries {
|
|
stateEventNIDs = append(stateEventNIDs, entry.EventNID)
|
|
}
|
|
stateEventNIDs = stateEventNIDs[:util.SortAndUnique(stateEventNIDs)]
|
|
return u.updater.EventIDs(u.ctx, stateEventNIDs)
|
|
}
|