Use channel for Matrix events to prevent concurrent sending to WhatsApp

matrix.go

@@ -445,7 +445,7 @@ func (mx *MatrixHandler) HandleMessage(evt *event.Event) {
 
 	portal := mx.bridge.GetPortalByMXID(evt.RoomID)
 	if portal != nil && (user.Whitelisted || portal.HasRelaybot()) {
-		portal.HandleMatrixMessage(user, evt)
+		portal.matrixMessages <- PortalMatrixMessage{user: user, evt: evt}
 	}
 }
 
@@ -479,7 +479,7 @@ func (mx *MatrixHandler) HandleRedaction(evt *event.Event) {
 
 	portal := mx.bridge.GetPortalByMXID(evt.RoomID)
 	if portal != nil && (user.Whitelisted || portal.HasRelaybot()) {
-		portal.HandleMatrixRedaction(user, evt)
+		portal.matrixMessages <- PortalMatrixMessage{user: user, evt: evt}
 	}
 }
 

portal.go

@@ -141,7 +141,8 @@ func (bridge *Bridge) NewManualPortal(key database.PortalKey) *Portal {
 		bridge: bridge,
 		log:    bridge.Log.Sub(fmt.Sprintf("Portal/%s", key)),
 
-		messages: make(chan PortalMessage, bridge.Config.Bridge.PortalMessageBuffer),
+		messages:       make(chan PortalMessage, bridge.Config.Bridge.PortalMessageBuffer),
+		matrixMessages: make(chan PortalMatrixMessage, bridge.Config.Bridge.PortalMessageBuffer),
 	}
 	portal.Key = key
 	go portal.handleMessageLoop()
@@ -154,7 +155,8 @@ func (bridge *Bridge) NewPortal(dbPortal *database.Portal) *Portal {
 		bridge: bridge,
 		log:    bridge.Log.Sub(fmt.Sprintf("Portal/%s", dbPortal.Key)),
 
-		messages: make(chan PortalMessage, bridge.Config.Bridge.PortalMessageBuffer),
+		messages:       make(chan PortalMessage, bridge.Config.Bridge.PortalMessageBuffer),
+		matrixMessages: make(chan PortalMatrixMessage, bridge.Config.Bridge.PortalMessageBuffer),
 	}
 	go portal.handleMessageLoop()
 	return portal
@@ -177,6 +179,11 @@ type PortalMessage struct {
 	source        *User
 }
 
+type PortalMatrixMessage struct {
+	evt  *event.Event
+	user *User
+}
+
 type recentlyHandledWrapper struct {
 	id  types.MessageID
 	err bool
@@ -201,34 +208,55 @@ type Portal struct {
 	currentlyTyping     []id.UserID
 	currentlyTypingLock sync.Mutex
 
-	messages chan PortalMessage
+	messages       chan PortalMessage
+	matrixMessages chan PortalMatrixMessage
 
 	relayUser *User
 }
 
-func (portal *Portal) handleMessageLoop() {
-	for msg := range portal.messages {
-		if len(portal.MXID) == 0 {
-			if msg.fake == nil && (msg.evt == nil || !containsSupportedMessage(msg.evt.Message)) {
-				portal.log.Debugln("Not creating portal room for incoming message: message is not a chat message")
-				continue
-			}
-			portal.log.Debugln("Creating Matrix room from incoming message")
-			err := portal.CreateMatrixRoom(msg.source, nil, false)
-			if err != nil {
-				portal.log.Errorln("Failed to create portal room:", err)
-				continue
-			}
+func (portal *Portal) handleMessageLoopItem(msg PortalMessage) {
+	if len(portal.MXID) == 0 {
+		if msg.fake == nil && (msg.evt == nil || !containsSupportedMessage(msg.evt.Message)) {
+			portal.log.Debugln("Not creating portal room for incoming message: message is not a chat message")
+			return
 		}
-		if msg.evt != nil {
-			portal.handleMessage(msg.source, msg.evt)
-		} else if msg.undecryptable != nil {
-			portal.handleUndecryptableMessage(msg.source, msg.undecryptable)
-		} else if msg.fake != nil {
-			msg.fake.ID = "FAKE::" + msg.fake.ID
-			portal.handleFakeMessage(*msg.fake)
-		} else {
-			portal.log.Warnln("Unexpected PortalMessage with no message: %+v", msg)
+		portal.log.Debugln("Creating Matrix room from incoming message")
+		err := portal.CreateMatrixRoom(msg.source, nil, false)
+		if err != nil {
+			portal.log.Errorln("Failed to create portal room:", err)
+			return
+		}
+	}
+	if msg.evt != nil {
+		portal.handleMessage(msg.source, msg.evt)
+	} else if msg.undecryptable != nil {
+		portal.handleUndecryptableMessage(msg.source, msg.undecryptable)
+	} else if msg.fake != nil {
+		msg.fake.ID = "FAKE::" + msg.fake.ID
+		portal.handleFakeMessage(*msg.fake)
+	} else {
+		portal.log.Warnln("Unexpected PortalMessage with no message: %+v", msg)
+	}
+}
+
+func (portal *Portal) handleMatrixMessageLoopItem(msg PortalMatrixMessage) {
+	switch msg.evt.Type {
+	case event.EventMessage, event.EventSticker:
+		portal.HandleMatrixMessage(msg.user, msg.evt)
+	case event.EventRedaction:
+		portal.HandleMatrixRedaction(msg.user, msg.evt)
+	default:
+		portal.log.Warnln("Unsupported event type %+v in portal message channel", msg.evt.Type)
+	}
+}
+
+func (portal *Portal) handleMessageLoop() {
+	for {
+		select {
+		case msg := <-portal.messages:
+			portal.handleMessageLoopItem(msg)
+		case msg := <-portal.matrixMessages:
+			portal.handleMatrixMessageLoopItem(msg)
 		}
 	}
 }