Use interval for keepalive timer, and fix the invalid dummy packet we were sending.

Author: haakonnessjoen

src/consts.js

@@ -1,7 +1,7 @@
 import { combineRgb } from '@companion-module/base'
 
 export const msgDelay = 5
-export const keepAliveTimeOut = 30000
+export const keepAliveTime = 30000
 
 export const DLE = 0x10
 export const STX = 0x02
@@ -165,4 +165,4 @@ export function getCommandName(value) {
 		}
 	}
 	return 'Unknown Command'
-}
+}

src/keepalive.js

@@ -1,26 +1,27 @@
-import { keepAliveTimeOut } from './consts.js'
+import { keepAliveTime } from './consts.js'
 
 export function startKeepAliveTimer() {
 	if (this.keepAliveTimer) {
-		clearTimeout(this.keepAliveTimer)
+		clearInterval(this.keepAliveTimer)
 	}
-	this.keepAliveTimer = setTimeout(() => {
+	this.keepAliveTimer = setInterval(() => {
 		this.keepAlive()
-	}, keepAliveTimeOut)
+	}, keepAliveTime)
 }
 
 export function stopKeepAliveTimer() {
 	if (this.keepAliveTimer) {
-		clearTimeout(this.keepAliveTimer)
+		clearInterval(this.keepAliveTimer)
 		// biome-ignore lint/performance/noDelete: not really a performance issue
 		delete this.keepAliveTimer
 	}
 }
 
 export function keepAlive() {
 	if (this.socket?.isConnected) {
-		//Send dummy message
-		this.sendMessage([0x00])
+		// Send dummy message if the queue is empty
+		if (this.queue.size === 0) {
+			this.sendMessage([])
+		}
 	}
-	this.startKeepAliveTimer()
 }

src/tcp.js

@@ -91,23 +91,21 @@ export function hasCommand(cmdCode) {
  */
 export function sendMessage(message) {
 	const msg = message instanceof Buffer ? message : Buffer.from(message)
-	if (msg.length < 1) {
-		this.log('warn', 'Empty or invalid message!')
-		return
-	}
 
-	// check that the command is implemented in the router
-	const cmdCode = msg[0]
-
-	if (
-		cmdCode !== 97 &&
-		cmdCode !== 0 &&
-		this.config.supported_commands_on_connect === true &&
-		this.commands.length > 0
-	) {
-		if (this.commands.indexOf(cmdCode) === -1) {
-			this.log('warn', `Command code ${cmdCode} is not implemented by this hardware`)
-			return
+	if (msg.length > 0) {
+		// check that the command is implemented in the router
+		const cmdCode = msg[0]
+
+		if (
+			cmdCode !== 97 &&
+			cmdCode !== 0 &&
+			this.config.supported_commands_on_connect === true &&
+			this.commands.length > 0
+		) {
+			if (this.commands.indexOf(cmdCode) === -1) {
+				this.log('warn', `Command code ${cmdCode} is not implemented by this hardware`)
+				return
+			}
 		}
 	}
 
@@ -148,7 +146,6 @@ export function sendMessage(message) {
 	this.queue.add(async () => {
 		if (this.socket?.isConnected) {
 			this.socket.send(packetBuffer)
-			this.startKeepAliveTimer()
 
 			this.addAckCallback(() => {
 				// Retry sending the command if it fails
@@ -170,6 +167,8 @@ export function init_tcp() {
 		delete this.socket
 	}
 
+	this.stopKeepAliveTimer()
+
 	if (this.config.host) {
 		this.socket = new TCPHelper(this.config.host, this.config.port)
 
@@ -183,6 +182,10 @@ export function init_tcp() {
 			this.stopKeepAliveTimer()
 		})
 
+		this.socket.on('close', () => {
+			this.stopKeepAliveTimer()
+		})
+
 		this.socket.on('connect', () => {
 			console.log(`Connected to ${this.config.host}:${this.config.port}`)
 			this.ackCallbacks = []