缺少“套接字”上的错误处理程序。 node.js / socket.io

Question

I get this error when i try to receive data from my client which is a video time of a video that updates every second or so. 当我尝试从客户端接收数据时出现此错误，这是每秒更新一次的视频的视频时间。 i think the error is happening on the client receive part but im not sure how to fix it. 我认为该错误正在客户端接收部分上发生，但我不确定如何解决。

this is the error 这是错误

this is my server code: 这是我的服务器代码：

var http = require("http");
var url = require('url');
var fs = require('fs');
var io = require('socket.io');

var server = http.createServer(function(request, response){
var path = url.parse(request.url).pathname;

switch(path){
    case '/':
        response.writeHead(200, {'Content-Type': 'text/html'});
        response.write('hello world');
        response.end();
        break;
    case '/index.html':
        fs.readFile(__dirname + path, function(error, data){
            if (error){
                response.writeHead(404);
                response.write("opps this doesn't exist - 404");
                response.end();
            }
            else{
                response.writeHead(200, {"Content-Type": "text/html"});
                response.write(data, "utf8");
                response.end();
            }
        });
        break;
        case '/main.js':
        fs.readFile(__dirname + path, function(error, data){
            if (error){
                response.writeHead(404);
                response.write("opps this doesn't exist - 404");
                response.end();
            }
            else{
                response.writeHead(200, {"Content-Type": "text/html"});
                response.write(data, "utf8");
                response.end();
            }
        });
        break;
        case '/remote-clock.js':
        fs.readFile(__dirname + path, function(error, data){
            if (error){
                response.writeHead(404);
                response.write("opps this doesn't exist - 404");
                response.end();
            }
            else{
                response.writeHead(200, {"Content-Type": "text/html"});
                response.write(data, "utf8");
                response.end();
            }
        });
        break;
    default:
        response.writeHead(404);
        response.write("opps this doesn't exist - 404");
        response.end();
        break;
}
});

server.listen(25565);

io.listen(server);


var listener = io.listen(server);

listener.sockets.on('connection', function(socket){
  //send data to client
  setInterval(function(){
    socket.emit('date', {'date': new Date()});
  }, 1000);

  //recieve client data
  socket.on('client_data', function(data){
    process.stdout.write(data.letter);
 });
});

this client code is : 该客户代码为：

<!DOCTYPE html>
 <html>
    <head>


             <script src="/socket.io/socket.io.js"></script>
   <script src="https://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.js"></script>

    <meta charset="utf-8"/>
    <meta http-equiv="X-UA-Compatible" content="IE-edge"/>
    <meta name="viewport" content="width=device-width, initial-scale=1, user-scalable=no, maximum-scale=1, width=device-width"/>
    <style type="text/css">
        body {
            font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif;

            padding: 0px;
            margin: 5%;
            width: 90%;
        }

        video {
            width: 100%;
        }

        #volume {
            width: 70%;
        }
    </style>
</head>
<body>
    <video id="video" autoplay>
        <source src="http://googledrive.com/host/0B-5FC9-wtiZzbTJFQnljdzNDdEE" type="video/mp4"/>
        <source src="http://googledrive.com/host/0B-5FC9-wtiZzbTJFQnljdzNDdEE" type="video/webm"/>
    </video>
    <div>
        <label>Volume: </label><input type="range" min="0" max="1" step="0.0001" value="1" id="volume"/>
        <button id="mute">Unmute</button>
        <button id="play">Play</button>

    </div>
    <div>Server Time: <span id="clock"></span></div>
    <div>Video Time: <span id="video-time"></span></div>
    <article>
        <h1>Synchronized Video Player</h1>
        <p><a href="" target="_blank">Open this page</a> in another browser window, even on another device, and the videos should be synchronized.</p>

    </article>


      <script>
      var video = document.getElementById('video');
  var socket = io.connect();
  socket.on('date', function(data){
    $('#date').text(data.date);
  });


   </script>
   <div id="date"></div>
  <textarea id="text"></textarea>


        <script src="http://cdn.jsdelivr.net/sockjs/0.3.4/sockjs.min.js">     </script>

        <script src="remote-clock.js"></script>
         <script src="main.js"></script>
    </body>
 </html>

my main.js code is : 我的main.js代码是：

(function (window) {
var CLOCK_PORT = 5001,
    EPSILON = -1 / 15,
    DURATION = 149.619,

    maxOffset = 1 / 30,
    video = document.getElementById('video'),
    clock = document.getElementById('clock'),
    videoTime = document.getElementById('video-time'),
    volume = document.getElementById('volume'),
    muted = document.getElementById('muted'),

    targetTime = 0,
    serverUrl,
    remoteClock,
    durationInMilliseconds,
    timeout,
    retries = 0,

    isBuffered;

function updateClockDisplay() {

    clock.textContent = (new Date(remoteClock.time())).toTimeString();
    videoTime.textContent = (video.currentTime).toFixed(2);
    requestAnimationFrame(updateClockDisplay);

  socket.emit('client_data', {'letter': videoTime});
  console.log(video.currentTime);


}

function checkAgain(delay) {
    clearTimeout(timeout);
    timeout = setTimeout(checkSync, delay);
}

function checkSync(evt) {
    var currentTime,
        current,
        currentBuffered,
        targetBuffered,
        targetDiff,
        currentDiff,
        skip;

    //currentTime is the time we should be at NOW
    currentTime = (remoteClock.time() % durationInMilliseconds) / 1000;

    //targetTime is the time we're seeking to and want to catch up to later
    //it's a little bit ahead of where we are so we can take time to buffer
    targetTime = Math.max(targetTime, currentTime);

    currentDiff = currentTime - video.currentTime;

    current = currentDiff > EPSILON && currentDiff < maxOffset;
    targetBuffered = isBuffered(targetTime);
    currentBuffered = isBuffered(currentTime) && isBuffered(currentTime + 2);

    if (currentBuffered && current) {
        video.play();
        retries = Math.min(2, retries);
        checkAgain(2000);
        return;
    }

    //we missed our window, so seek ahead and try again
    if (currentDiff >= EPSILON && video.readyState < 2 || currentDiff > 1) {
        skip = Math.pow(2, Math.min(4, Math.max(retries, 1)));
        targetTime = (currentTime + skip) % DURATION;
        video.pause();
        video.currentTime = targetTime;
        retries++;
        maxOffset = Math.max(maxOffset, retries * 0.1);
        checkAgain(1000);
        return;
    }

    //we haven't caught up yet, so give it a little more time to buffer and check in again
    targetDiff = targetTime - currentTime;
    checkAgain(targetDiff * 500);
}

function stateUpdate(evt) {
    if (!video.duration) {
        console.log('No video duration yet');
        video.pause();
        return;
    }

    console.log('video metadata', video.duration, video.videoWidth, video.videoHeight);
    durationInMilliseconds = Math.round(DURATION * 1000);
    if (remoteClock.accuracy() > 100) {
        return;
    }

    checkSync(evt || 'clock update');
}

function timeBuffered(time) {
    var i;
    if (!video.buffered) {
        return true;
    }

    for (i = 0; i < video.buffered.length; i++) {
        if (video.buffered.start(i) > time) {
            return false;
        }
        if (video.buffered.end(i) >= time) {
            return true;
        }
    }
    return false;
}



serverUrl = location.protocol + '//' + location.hostname + ':' + CLOCK_PORT + '/time-server';
remoteClock = new RemoteClock(serverUrl, stateUpdate);



video.muted = true;
video.addEventListener('durationchange', stateUpdate, false);
//video.addEventListener('waiting', stateUpdate, false);
//video.addEventListener('seeked', stateUpdate, false);
video.addEventListener('volumechange', function () {
    volume.value = video.volume;
    if (video.muted) {
        mute.textContent = 'Unmute';
    } else {
        mute.textContent = 'Mute';
    }
});
mute.addEventListener('click', function () {
    video.muted = !video.muted;
});
volume.addEventListener('input', function () {
    video.volume = volume.value;
});



play.addEventListener('click', function () {


    if (video.paused) {
        play.textContent = 'Play';
        video.play(); 
    } else {
        play.textContent = 'Pause';
        video.pause();
    }
});









window.addEventListener('touchstart', function touchstart(evt) {
    video.load();
    evt.preventDefault();
    window.removeEventListener('touchstart', touchstart, true);
}, true);
updateClockDisplay();
}(this));

Answer 1

The error is appearing on line 80, this line: 错误出现在第80行，此行：

process.stdout.write(data.letter);

If you open up an interactive node session and type 如果打开交互式节点会话并输入

process.stdout.write({a: "b"});

it gives an error about invalid data saying that you cannot pass an object to process.stdout.write , only a string or buffer. 它给出了有关无效数据的错误，指出您不能将对象传递给process.stdout.write ，而只能传递字符串或缓冲区。 You are sending {'letter': videoTime} to the server, and videoTime refers to an HTML element, which is an object. 您正在向服务器发送{'letter': videoTime} ，并且videoTime引用HTML元素，它是一个对象。 You are typing to write the HTML element to the console. 您正在键入将HTML元素写入控制台。 If what you want to pass to the server is the video time and not the HTML element that holds the video time, you can change the client code to 如果要传递给服务器的是视频时间而不是保存视频时间的HTML元素，则可以将客户端代码更改为

{'letter': videoTime.textContent}

缺少“套接字”上的错误处理程序。 node.js / socket.io

问题描述

1 个解决方案

解决方案1
0 已采纳 2016-05-29 16:06:12

缺少“套接字”上的错误处理程序。 node.js / socket.io

问题描述

1 个解决方案

解决方案1 0 已采纳 2016-05-29 16:06:12

解决方案1
0 已采纳 2016-05-29 16:06:12