[Federation] Send typing events (#572)

* GetJoinedHosts from federation server db

* Add dummy api.OutputTypingEvent

* Add a typing server consumer to federation sender

* Update queue to support EDU events

* Update OutputTypingEvent format

* Use SendEDU in federation server, remove dummy/api

* Add helpful comments

* fix typo

* remove origin field

* Count EDUs in sendCounter

src/github.com/matrix-org/dendrite/federationsender/consumers/typingserver.go

@@ -0,0 +1,96 @@
+// 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/common"
+	"github.com/matrix-org/dendrite/common/config"
+	"github.com/matrix-org/dendrite/federationsender/queue"
+	"github.com/matrix-org/dendrite/federationsender/storage"
+	"github.com/matrix-org/dendrite/typingserver/api"
+	"github.com/matrix-org/gomatrixserverlib"
+	log "github.com/sirupsen/logrus"
+	"gopkg.in/Shopify/sarama.v1"
+)
+
+// OutputTypingEventConsumer consumes events that originate in typing server.
+type OutputTypingEventConsumer struct {
+	consumer   *common.ContinualConsumer
+	db         *storage.Database
+	queues     *queue.OutgoingQueues
+	ServerName gomatrixserverlib.ServerName
+}
+
+// NewOutputTypingEventConsumer creates a new OutputTypingEventConsumer. Call Start() to begin consuming from typing servers.
+func NewOutputTypingEventConsumer(
+	cfg *config.Dendrite,
+	kafkaConsumer sarama.Consumer,
+	queues *queue.OutgoingQueues,
+	store *storage.Database,
+) *OutputTypingEventConsumer {
+	consumer := common.ContinualConsumer{
+		Topic:          string(cfg.Kafka.Topics.OutputTypingEvent),
+		Consumer:       kafkaConsumer,
+		PartitionStore: store,
+	}
+	c := &OutputTypingEventConsumer{
+		consumer:   &consumer,
+		queues:     queues,
+		db:         store,
+		ServerName: cfg.Matrix.ServerName,
+	}
+	consumer.ProcessMessage = c.onMessage
+
+	return c
+}
+
+// Start consuming from typing servers
+func (t *OutputTypingEventConsumer) Start() error {
+	return t.consumer.Start()
+}
+
+// onMessage is called for OutputTypingEvent received from the typing servers.
+// Parses the msg, creates a matrix federation EDU and sends it to joined hosts.
+func (t *OutputTypingEventConsumer) onMessage(msg *sarama.ConsumerMessage) error {
+	// Extract the typing event from msg.
+	var ote api.OutputTypingEvent
+	if err := json.Unmarshal(msg.Value, &ote); err != nil {
+		// Skip this msg but continue processing messages.
+		log.WithError(err).Errorf("typingserver output log: message parse failed")
+		return nil
+	}
+
+	joined, err := t.db.GetJoinedHosts(context.TODO(), ote.Event.RoomID)
+	if err != nil {
+		return err
+	}
+
+	names := make([]gomatrixserverlib.ServerName, len(joined))
+	for i := range joined {
+		names[i] = joined[i].ServerName
+	}
+
+	edu := &gomatrixserverlib.EDU{Type: ote.Event.Type}
+	if edu.Content, err = json.Marshal(map[string]interface{}{
+		"room_id": ote.Event.RoomID,
+		"user_id": ote.Event.UserID,
+		"typing":  ote.Event.Typing,
+	}); err != nil {
+		return err
+	}
+
+	return t.queues.SendEDU(edu, t.ServerName, names)
+}

src/github.com/matrix-org/dendrite/federationsender/federationsender.go

@@ -38,11 +38,18 @@ func SetupFederationSenderComponent(
 
 	queues := queue.NewOutgoingQueues(base.Cfg.Matrix.ServerName, federation)
 
-	consumer := consumers.NewOutputRoomEventConsumer(
+	rsConsumer := consumers.NewOutputRoomEventConsumer(
 		base.Cfg, base.KafkaConsumer, queues,
 		federationSenderDB, queryAPI,
 	)
-	if err = consumer.Start(); err != nil {
+	if err = rsConsumer.Start(); err != nil {
 		logrus.WithError(err).Panic("failed to start room server consumer")
 	}
+
+	tsConsumer := consumers.NewOutputTypingEventConsumer(
+		base.Cfg, base.KafkaConsumer, queues, federationSenderDB,
+	)
+	if err := tsConsumer.Start(); err != nil {
+		logrus.WithError(err).Panic("failed to start typing server consumer")
+	}
 }

src/github.com/matrix-org/dendrite/federationsender/queue/destinationqueue.go

@@ -33,12 +33,13 @@ type destinationQueue struct {
 	origin      gomatrixserverlib.ServerName
 	destination gomatrixserverlib.ServerName
 	// The running mutex protects running, sentCounter, lastTransactionIDs and
-	// pendingEvents.
+	// pendingEvents, pendingEDUs.
 	runningMutex       sync.Mutex
 	running            bool
 	sentCounter        int
 	lastTransactionIDs []gomatrixserverlib.TransactionID
 	pendingEvents      []*gomatrixserverlib.Event
+	pendingEDUs        []*gomatrixserverlib.EDU
 }
 
 // Send event adds the event to the pending queue for the destination.
@@ -54,6 +55,19 @@ func (oq *destinationQueue) sendEvent(ev *gomatrixserverlib.Event) {
 	}
 }
 
+// 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 event to that destination.
+func (oq *destinationQueue) sendEDU(e *gomatrixserverlib.EDU) {
+	oq.runningMutex.Lock()
+	defer oq.runningMutex.Unlock()
+	oq.pendingEDUs = append(oq.pendingEDUs, e)
+	if !oq.running {
+		oq.running = true
+		go oq.backgroundSend()
+	}
+}
+
 func (oq *destinationQueue) backgroundSend() {
 	for {
 		t := oq.next()
@@ -82,10 +96,12 @@ func (oq *destinationQueue) backgroundSend() {
 func (oq *destinationQueue) next() *gomatrixserverlib.Transaction {
 	oq.runningMutex.Lock()
 	defer oq.runningMutex.Unlock()
-	if len(oq.pendingEvents) == 0 {
+
+	if len(oq.pendingEvents) == 0 && len(oq.pendingEDUs) == 0 {
 		oq.running = false
 		return nil
 	}
+
 	var t gomatrixserverlib.Transaction
 	now := gomatrixserverlib.AsTimestamp(time.Now())
 	t.TransactionID = gomatrixserverlib.TransactionID(fmt.Sprintf("%d-%d", now, oq.sentCounter))
@@ -96,11 +112,20 @@ func (oq *destinationQueue) next() *gomatrixserverlib.Transaction {
 	if t.PreviousIDs == nil {
 		t.PreviousIDs = []gomatrixserverlib.TransactionID{}
 	}
+
 	oq.lastTransactionIDs = []gomatrixserverlib.TransactionID{t.TransactionID}
+
 	for _, pdu := range oq.pendingEvents {
 		t.PDUs = append(t.PDUs, *pdu)
 	}
 	oq.pendingEvents = nil
 	oq.sentCounter += len(t.PDUs)
+
+	for _, edu := range oq.pendingEDUs {
+		t.EDUs = append(t.EDUs, *edu)
+	}
+	oq.pendingEDUs = nil
+	oq.sentCounter += len(t.EDUs)
+
 	return &t
 }

src/github.com/matrix-org/dendrite/federationsender/queue/queue.go

@@ -47,10 +47,7 @@ func (oqs *OutgoingQueues) SendEvent(
 	destinations []gomatrixserverlib.ServerName,
 ) error {
 	if origin != oqs.origin {
-		// TODO: Support virtual hosting by allowing us to send events using
+		// TODO: Support virtual hosting; gh issue #577.
-		// different origin server names.
-		// For now assume we are always asked to send as the single server configured
-		// in the dendrite config.
 		return fmt.Errorf(
 			"sendevent: unexpected server to send as: got %q expected %q",
 			origin, oqs.origin,
@@ -76,8 +73,49 @@ func (oqs *OutgoingQueues) SendEvent(
 			}
 			oqs.queues[destination] = oq
 		}
+
 		oq.sendEvent(ev)
 	}
+
+	return nil
+}
+
+// SendEDU sends an EDU event to the destinations
+func (oqs *OutgoingQueues) SendEDU(
+	e *gomatrixserverlib.EDU, origin gomatrixserverlib.ServerName,
+	destinations []gomatrixserverlib.ServerName,
+) error {
+	if origin != oqs.origin {
+		// TODO: Support virtual hosting; gh issue #577.
+		return fmt.Errorf(
+			"sendevent: unexpected server to send as: got %q expected %q",
+			origin, oqs.origin,
+		)
+	}
+
+	// Remove our own server from the list of destinations.
+	destinations = filterDestinations(oqs.origin, destinations)
+
+	log.WithFields(log.Fields{
+		"destinations": destinations, "edu_type": e.Type,
+	}).Info("Sending EDU event")
+
+	oqs.queuesMutex.Lock()
+	defer oqs.queuesMutex.Unlock()
+	for _, destination := range destinations {
+		oq := oqs.queues[destination]
+		if oq == nil {
+			oq = &destinationQueue{
+				origin:      oqs.origin,
+				destination: destination,
+				client:      oqs.client,
+			}
+			oqs.queues[destination] = oq
+		}
+
+		oq.sendEDU(e)
+	}
+
 	return nil
 }
 

src/github.com/matrix-org/dendrite/federationsender/storage/joined_hosts_table.go

@@ -97,10 +97,22 @@ func (s *joinedHostsStatements) deleteJoinedHosts(
 	return err
 }
 
-func (s *joinedHostsStatements) selectJoinedHosts(
+func (s *joinedHostsStatements) selectJoinedHostsWithTx(
 	ctx context.Context, txn *sql.Tx, roomID string,
 ) ([]types.JoinedHost, error) {
 	stmt := common.TxStmt(txn, s.selectJoinedHostsStmt)
+	return joinedHostsFromStmt(ctx, stmt, roomID)
+}
+
+func (s *joinedHostsStatements) selectJoinedHosts(
+	ctx context.Context, roomID string,
+) ([]types.JoinedHost, error) {
+	return joinedHostsFromStmt(ctx, s.selectJoinedHostsStmt, roomID)
+}
+
+func joinedHostsFromStmt(
+	ctx context.Context, stmt *sql.Stmt, roomID string,
+) ([]types.JoinedHost, error) {
 	rows, err := stmt.QueryContext(ctx, roomID)
 	if err != nil {
 		return nil, err
@@ -118,5 +130,6 @@ func (s *joinedHostsStatements) selectJoinedHosts(
 			ServerName:    gomatrixserverlib.ServerName(serverName),
 		})
 	}
+
 	return result, nil
 }

src/github.com/matrix-org/dendrite/federationsender/storage/storage.go

@@ -92,7 +92,7 @@ func (d *Database) UpdateRoom(
 			}
 		}
 
-		joinedHosts, err = d.selectJoinedHosts(ctx, txn, roomID)
+		joinedHosts, err = d.selectJoinedHostsWithTx(ctx, txn, roomID)
 		if err != nil {
 			return err
 		}
@@ -110,3 +110,12 @@ func (d *Database) UpdateRoom(
 	})
 	return
 }
+
+// GetJoinedHosts returns the currently joined hosts for room,
+// as known to federationserver.
+// Returns an error if something goes wrong.
+func (d *Database) GetJoinedHosts(
+	ctx context.Context, roomID string,
+) ([]types.JoinedHost, error) {
+	return d.selectJoinedHosts(ctx, roomID)
+}

src/github.com/matrix-org/dendrite/typingserver/api/output.go

@@ -13,19 +13,19 @@
 package api
 
 // OutputTypingEvent is an entry in typing server output kafka log.
+// This contains the event with extra fields used to create 'm.typing' event
+// in clientapi & federation.
 type OutputTypingEvent struct {
 	// The Event for the typing edu event.
 	Event TypingEvent `json:"event"`
+	// Users typing in the room when the event was generated.
+	TypingUsers []string `json:"typing_users"`
 }
 
 // TypingEvent represents a matrix edu event of type 'm.typing'.
 type TypingEvent struct {
-	Type    string             `json:"type"`
+	Type   string `json:"type"`
-	RoomID  string             `json:"room_id"`
+	RoomID string `json:"room_id"`
-	Content TypingEventContent `json:"content"`
+	UserID string `json:"user_id"`
-}
+	Typing bool   `json:"typing"`
-
-// TypingEventContent for TypingEvent
-type TypingEventContent struct {
-	UserIDs []string `json:"user_ids"`
 }

src/github.com/matrix-org/dendrite/typingserver/input/input.go

@@ -53,24 +53,29 @@ func (t *TypingServerInputAPI) InputTypingEvent(
 		t.Cache.RemoveUser(ite.UserID, ite.RoomID)
 	}
 
-	return t.sendUpdateForRoom(ite.RoomID)
+	return t.sendEvent(ite)
 }
 
-func (t *TypingServerInputAPI) sendUpdateForRoom(roomID string) error {
+func (t *TypingServerInputAPI) sendEvent(ite *api.InputTypingEvent) error {
-	userIDs := t.Cache.GetTypingUsers(roomID)
+	userIDs := t.Cache.GetTypingUsers(ite.RoomID)
-	event := &api.TypingEvent{
+	ev := &api.TypingEvent{
-		Type:    gomatrixserverlib.MTyping,
+		Type:   gomatrixserverlib.MTyping,
-		RoomID:  roomID,
+		RoomID: ite.RoomID,
-		Content: api.TypingEventContent{UserIDs: userIDs},
+		UserID: ite.UserID,
 	}
-	eventJSON, err := json.Marshal(api.OutputTypingEvent{Event: *event})
+	ote := &api.OutputTypingEvent{
+		Event:       *ev,
+		TypingUsers: userIDs,
+	}
+
+	eventJSON, err := json.Marshal(ote)
 	if err != nil {
 		return err
 	}
 
 	m := &sarama.ProducerMessage{
 		Topic: string(t.OutputTypingEventTopic),
-		Key:   sarama.StringEncoder(roomID),
+		Key:   sarama.StringEncoder(ite.RoomID),
 		Value: sarama.ByteEncoder(eventJSON),
 	}