feat: upgrade socket-io example to latest serialport and fix bug (#1505)

examples/socketio/index.js

@@ -12,16 +12,17 @@
 const app = require('express')();
 const http = require('http').Server(app);
 const io = require('socket.io')(http);
-const port = process.env.PORT || 3000;
+const tcpPort = process.env.PORT || 3000;
 
-const serialport = require('serialport');
-const SerialPort = serialport.SerialPort;
+const SerialPort = require('serialport');
 
-const serial = new SerialPort('/dev/cu.usbmodem1411', {
-  baudRate: 9600,
-  parser: SerialPort.parsers.byteLength(1)
+const port = new SerialPort('/dev/cu.usbmodem1411', {
+  baudRate: 9600
 });
 
+const byteParser = new SerialPort.parsers.ByteLength({ length: 1 });
+port.pipe(byteParser);
+
 // Values to send over to Arduino.
 const HIGH = Buffer.from([1]);
 const LOW = Buffer.from([0]);
@@ -36,8 +37,8 @@ app.get('/', (req, res) => {
   res.sendfile('index.html');
 });
 
-http.listen(port, () => {
-  console.log(`listening on *:${port}`);
+http.listen(tcpPort, () => {
+  console.log(`listening on http://localhost:${tcpPort}`);
 });
 
 /* ===========================================
@@ -57,10 +58,10 @@ io.on('connection', (socket) => {
     console.log('Message received: ', msg);
     switch (msg) {
       case 'on':
-        serial.write(HIGH);
+        port.write(HIGH);
         break;
       case 'off':
-        serial.write(LOW);
+        port.write(LOW);
         break;
       default:
         break;
@@ -74,15 +75,14 @@ io.on('connection', (socket) => {
 *
 =========================================== */
 
-serial.on('open', () => {
+port.on('open', () => {
   console.log('Port is open!');
 });
 
 /**
- * EventListener to receive data from .ino script uploaded to Arduino.
- *
+ * listen to the bytes as they are parsed from the parser.
  */
-serial.on('data', (data) => {
+byteParser.on('data', (data) => {
   let message;
 
   if (HIGH.compare(data) === 0) {
@@ -96,7 +96,7 @@ serial.on('data', (data) => {
   io.sockets.emit('new message', message);
 });
 
-serial.on('close', () => {
+port.on('close', () => {
   console.log('Serial port disconnected.');
   io.sockets.emit('close');
 });

examples/socketio/ledWrite.ino

@@ -9,6 +9,6 @@ void loop() {
   while (Serial.available()) {
     int byte = Serial.read();
     digitalWrite(LED_BUILTIN, byte);
-    Serial.print(byte);
+    Serial.write(byte);
   }
-}
+}

examples/socketio/package.json

@@ -1,17 +1,16 @@
 {
-  "name": "socketio-example",
-  "version": "1.0.0",
+  "name": "serialport-socketio-example",
+  "version": "1.0.1",
   "description": "LED switch example written for node-serialport.",
   "main": "index.js",
   "dependencies": {
     "express": "^4.14.1",
-    "serialport": "^4.0.7",
+    "serialport": "^6.0.0",
     "socket.io": "^1.7.2"
   },
   "devDependencies": {},
   "scripts": {
     "start": "node index.js"
   },
-  "author": "GitHub",
-  "license": "CC0-1.0"
+  "license": "MIT"
 }