dendrite/federationsender/queue/destinationqueue.go

299 lines
9.7 KiB
Go

// Copyright 2017 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 queue
import (
"context"
"encoding/json"
"fmt"
"sync"
"time"
"github.com/matrix-org/dendrite/federationsender/producers"
"github.com/matrix-org/dendrite/federationsender/types"
"github.com/matrix-org/gomatrixserverlib"
"github.com/sirupsen/logrus"
log "github.com/sirupsen/logrus"
"go.uber.org/atomic"
)
// destinationQueue is a queue of events for a single destination.
// It is responsible for sending the events to the destination and
// ensures that only one request is in flight to a given destination
// at a time.
type destinationQueue struct {
rsProducer *producers.RoomserverProducer // roomserver producer
client *gomatrixserverlib.FederationClient // federation client
origin gomatrixserverlib.ServerName // origin of requests
destination gomatrixserverlib.ServerName // destination of requests
running atomic.Bool // is the queue worker running?
wakeup chan bool // wakes up a sleeping worker
statistics *types.ServerStatistics // statistics about this remote server
idleCounter atomic.Uint32 // how many ticks have we done nothing?
runningMutex sync.RWMutex // protects the below
lastTransactionIDs []gomatrixserverlib.TransactionID // protected by runningMutex
pendingPDUs []*gomatrixserverlib.HeaderedEvent // protected by runningMutex
pendingEDUs []*gomatrixserverlib.EDU // protected by runningMutex
pendingInvites []*gomatrixserverlib.InviteV2Request // protected by runningMutex
}
// Start the destination queue if it needs to be started, or
// otherwise signal to it that it should wake up from sleep.
func (oq *destinationQueue) wake() {
if !oq.running.Load() {
go oq.backgroundSend()
} else {
oq.wakeup <- true
}
}
// Send event adds the event to the pending queue for the destination.
// If the queue is empty then it starts a background goroutine to
// start sending events to that destination.
func (oq *destinationQueue) sendEvent(ev *gomatrixserverlib.HeaderedEvent) {
if oq.statistics.Blacklisted() {
// If the destination is blacklisted then drop the event.
return
}
oq.runningMutex.Lock()
oq.pendingPDUs = append(oq.pendingPDUs, ev)
oq.runningMutex.Unlock()
oq.wake()
}
// sendEDU adds the EDU event to the pending queue for the destination.
// If the queue is empty then it starts a background goroutine to
// start sending events to that destination.
func (oq *destinationQueue) sendEDU(ev *gomatrixserverlib.EDU) {
if oq.statistics.Blacklisted() {
// If the destination is blacklisted then drop the event.
return
}
oq.runningMutex.Lock()
oq.pendingEDUs = append(oq.pendingEDUs, ev)
oq.runningMutex.Unlock()
oq.wake()
}
// sendInvite adds the invite event to the pending queue for the
// destination. If the queue is empty then it starts a background
// goroutine to start sending events to that destination.
func (oq *destinationQueue) sendInvite(ev *gomatrixserverlib.InviteV2Request) {
if oq.statistics.Blacklisted() {
// If the destination is blacklisted then drop the event.
return
}
oq.runningMutex.Lock()
oq.pendingInvites = append(oq.pendingInvites, ev)
oq.runningMutex.Unlock()
oq.wake()
}
// backgroundSend is the worker goroutine for sending events.
// nolint:gocyclo
func (oq *destinationQueue) backgroundSend() {
// Mark the worker as running for its lifetime.
oq.wakeup = make(chan bool)
oq.running.Store(true)
defer oq.running.Store(false)
defer close(oq.wakeup)
for {
// If we are backing off this server then wait for the
// backoff duration to complete first.
if backoff, duration := oq.statistics.BackoffDuration(); backoff {
<-time.After(duration)
}
// Retrieve any waiting things.
oq.runningMutex.RLock()
pendingPDUs, pendingEDUs := oq.pendingPDUs, oq.pendingEDUs
pendingInvites := oq.pendingInvites
idleCounter, sentCounter := oq.idleCounter.Load(), oq.statistics.SuccessCount()
oq.runningMutex.RUnlock()
// If we have pending PDUs or EDUs then construct a transaction.
if len(pendingPDUs) > 0 || len(pendingEDUs) > 0 {
// Try sending the next transaction and see what happens.
transaction, terr := oq.nextTransaction(pendingPDUs, pendingEDUs, sentCounter)
if terr != nil {
// We failed to send the transaction.
if giveUp := oq.statistics.Failure(); giveUp {
// It's been suggested that we should give up because
// the backoff has exceeded a maximum allowable value.
return
}
continue
}
// If we successfully sent the transaction then clear out
// the pending events and EDUs.
if transaction {
oq.runningMutex.Lock()
// Reallocate so that the underlying arrays can be GC'd, as
// opposed to growing forever.
oq.pendingPDUs = append(
[]*gomatrixserverlib.HeaderedEvent{},
oq.pendingPDUs[len(pendingPDUs):]...,
)
oq.pendingEDUs = append(
[]*gomatrixserverlib.EDU{},
oq.pendingEDUs[len(pendingEDUs):]...,
)
oq.runningMutex.Unlock()
}
}
// Try sending the next invite and see what happens.
if len(pendingInvites) > 0 {
invites, ierr := oq.nextInvites(pendingInvites)
if ierr != nil {
// We failed to send the transaction so increase the
// backoff and give it another go shortly.
if giveUp := oq.statistics.Failure(); giveUp {
// It's been suggested that we should give up because
// the backoff has exceeded a maximum allowable value.
return
}
continue
}
// If we successfully sent the invites then clear out
// the pending invites.
if invites {
oq.runningMutex.Lock()
// Reallocate so that the underlying array can be GC'd, as
// opposed to growing forever.
oq.pendingInvites = append(
[]*gomatrixserverlib.InviteV2Request{},
oq.pendingInvites[len(pendingInvites):]...,
)
oq.runningMutex.Unlock()
}
}
// If everything was fine at this point then we can update
// the counters for the transaction IDs.
oq.statistics.Success()
// Wait either for a few seconds, or until a new event is
// available.
select {
case <-oq.wakeup:
case <-time.After(time.Second * 5):
// If this worker has been idle for a while then stop
// running it, otherwise the goroutine will just tick
// endlessly. It'll get automatically restarted when
// a new event needs to be sent.
if idleCounter >= 5 {
return
}
}
}
}
// nextTransaction creates a new transaction from the pending event
// queue and sends it. Returns true if a transaction was sent or
// false otherwise.
func (oq *destinationQueue) nextTransaction(
pendingPDUs []*gomatrixserverlib.HeaderedEvent,
pendingEDUs []*gomatrixserverlib.EDU,
sentCounter uint32,
) (bool, error) {
t := gomatrixserverlib.Transaction{
PDUs: []json.RawMessage{},
EDUs: []gomatrixserverlib.EDU{},
}
now := gomatrixserverlib.AsTimestamp(time.Now())
t.TransactionID = gomatrixserverlib.TransactionID(fmt.Sprintf("%d-%d", now, sentCounter))
t.Origin = oq.origin
t.Destination = oq.destination
t.OriginServerTS = now
t.PreviousIDs = oq.lastTransactionIDs
if t.PreviousIDs == nil {
t.PreviousIDs = []gomatrixserverlib.TransactionID{}
}
oq.lastTransactionIDs = []gomatrixserverlib.TransactionID{t.TransactionID}
for _, pdu := range pendingPDUs {
// Append the JSON of the event, since this is a json.RawMessage type in the
// gomatrixserverlib.Transaction struct
t.PDUs = append(t.PDUs, (*pdu).JSON())
}
for _, edu := range pendingEDUs {
t.EDUs = append(t.EDUs, *edu)
}
logrus.WithField("server_name", oq.destination).Infof("Sending transaction %q containing %d PDUs, %d EDUs", t.TransactionID, len(t.PDUs), len(t.EDUs))
_, err := oq.client.SendTransaction(context.TODO(), t)
if err != nil {
log.WithFields(log.Fields{
"destination": oq.destination,
log.ErrorKey: err,
}).Info("problem sending transaction")
return false, err
}
return true, nil
}
// nextInvite takes pending invite events from the queue and sends
// them. Returns true if a transaction was sent or false otherwise.
func (oq *destinationQueue) nextInvites(
pendingInvites []*gomatrixserverlib.InviteV2Request,
) (bool, error) {
for _, inviteReq := range pendingInvites {
ev, roomVersion := inviteReq.Event(), inviteReq.RoomVersion()
log.WithFields(log.Fields{
"event_id": ev.EventID(),
"room_version": roomVersion,
"destination": oq.destination,
}).Info("sending invite")
inviteRes, err := oq.client.SendInviteV2(
context.TODO(),
oq.destination,
*inviteReq,
)
if err != nil {
log.WithFields(log.Fields{
"event_id": ev.EventID(),
"state_key": ev.StateKey(),
"destination": oq.destination,
}).WithError(err).Error("failed to send invite")
return false, err
}
if _, err = oq.rsProducer.SendInviteResponse(
context.TODO(),
inviteRes,
roomVersion,
); err != nil {
log.WithFields(log.Fields{
"event_id": ev.EventID(),
"state_key": ev.StateKey(),
"destination": oq.destination,
}).WithError(err).Error("failed to return signed invite to roomserver")
return false, err
}
}
return true, nil
}