Question

我是网络开发和JS的新手，我一直在努力让一个节点js服务器托管一个网页，该网页将串行命令发送到连接到Windows 7＆＃34;服务器＆的设备＃34 ;.它可以在localhost：8000上的服务器上运行，并将html传送到远程计算机，但它不会在服务器上发送串行命令的后端进程（从远程PC运行时）。

server.js代码：

＆＃13;

var app = require('http').createServer(handler),
  io = require('socket.io').listen(app),
  fs = require('fs'),
  url = require('url'),
  SerialPort = require('serialport')//.SerialPort,
  // initialize serialport using the /dev/cu.usbmodem1411 serial port
  // remember to change this string if your arduino is using a different serial port
  sp = new SerialPort('COM3',{
  //'/dev/cu.usbmodem1411', {
    baudRate: 9600,
	parser:SerialPort.parsers.readline("\r\n")
  }),
  // this var will contain the message string dispatched by arduino
  arduinoMessage = '',
  /**
   * helper function to load any app file required by client.html
   * @param  { String } pathname: path of the file requested to the nodejs server
   * @param  { Object } res: http://nodejs.org/api/http.html#http_class_http_serverresponse
   */
  readFile = function(pathname, res) {
    // an empty path returns client.html
    if (pathname === '/')
      pathname = 'client.html';

    fs.readFile('client/' + pathname, function(err, data) {
      if (err) {
        console.log(err);
        res.writeHead(500);
        return res.end('Error loading client.html');
      }
      res.writeHead(200);
      res.end(data);
    });
  },
  /**
   *
   * This function is used as proxy to print the arduino messages into the nodejs console and on the page
   * @param  { Buffer } buffer: buffer data sent via serialport
   * @param  { Object } socket: it's the socket.io instance managing the connections with the client.html page
   *
   */
  sendMessage = function(buffer, socket) {
    // concatenating the string buffers sent via usb port
    arduinoMessage += buffer.toString();

    // detecting the end of the string
    if (arduinoMessage.indexOf('\r') >= 0) {
      // log the message into the terminal
      // console.log(arduinoMessage);
      // send the message to the client
      socket.volatile.emit('notification', arduinoMessage);
      // reset the output string to an empty value
      arduinoMessage = '';
    }
  };

// creating a new websocket
io.sockets.on('connection', function(socket) {
  // listen all the serial port messages sent from arduino and passing them to the proxy function sendMessage
  sp.on('data', function(data) {
    sendMessage(data, socket);
  });
  // listen all the websocket "lightStatus" messages coming from the client.html page
  socket.on('lightStatus', function(lightStatus) {
    sp.write(lightStatus + '\r', function() {
      // log the light status into the terminal
      console.log('the light should be: ' + lightStatus);
    });
  });
});

// just some debug listeners
sp.on('close', function(err) {
  console.log('Port closed!');
});

sp.on('error', function(err) {
  console.error('error', err);
});

//sp.on('data', function(data){
//	console.log("on Data ");
//});
sp.on('data', showSerialData);
function showSerialData(data){
console.log(data);}

sp.on('open', function() {
  console.log('Port opened!');
});

 // creating the server ( localhost:80 )
app.listen(8000);
// server handler
function handler(req, res) {
  readFile(url.parse(req.url).pathname, res);
}

＆＃13;

和app.js：

＆＃13;

(function() {
  'use strict';
  // create a new websocket
  var socket = io.connect('http://localhost:8000'),
    // select all the DOM elements needed for this experiment
    $body = $('body'),
    $btn = $('button'),
    $lightStatus = $('span', $btn),
    // the light must be off by default
    lightStatus = 'off',
    // toggle the light status using the button on the page
    toggleLightStatus = function() {
      // switch the lightStatus var ...
      lightStatus = lightStatus === 'off' ? 'on' : 'off';
      // pass its value to the nodejs server via websocket
      socket.emit('lightStatus', lightStatus);

    },
    onSocketNotification = function(data) {
      // print all the messages coming from the arduino board
      var $div = $('<center>');
      $div.html(data);
      $body.append($div);
      $div.delay(1000).fadeOut(function() {
        $div.remove();
      });
      // filter the light status notifications
      if (/on|off/gi.test(data)) {
        // update the text inside the button
        $lightStatus.text(data);
      }

    };

  // Set listeners
  socket.on('notification', onSocketNotification);
  $btn.on('click', toggleLightStatus);

  // turn off the light by default on any new connection
  socket.emit('lightStatus', lightStatus);
}());

＆＃13;

以下是调用应用的HTML

＆＃13;

<html>
<head>
    <!--
     * Author:      Gianluca Guarini
     * Contact:     gianluca.guarini@gmail.com
     * Website:     http://www.gianlucaguarini.com/
     * Twitter:     @gianlucaguarini
    -->
    <title>Arduino and Nodejs</title>
    <style>
    center {
        font-size: 100px;
        font-family:arial;
    }
    </style>
</head>
<body>
    <button>
        Turn the light
        <span>on</span>
    </button>
    <script src="socket.io/socket.io.js"></script>
    <script src="http://code.jquery.com/jquery-latest.min.js"></script>
    <script src="js/app.js"></script>
</body>
</html>

＆＃13;

Node JS服务器应用程序无法从远程客户端工作

0 个答案: