我在服务器端使用带有node.js的ws，在客户端使用常规的WebSocket API。打开连接和消息来回几次工作正常。但是插座总是会在一两分钟后关闭。阿伦他们应该坚持下去吗？我做错了吗？
我的服务器是在heroku上托管的node.js.我刚刚使用foreman start（本地运行服务器的heroku工具）再次在本地测试，并且套接字根本没有意外关闭，所以可能它在heroku上配置错误。无论如何，这里是一个相关的代码示例，为简洁起见省略了一些函数。
我在OSX Yosemite上测试Chrome中的应用程序，但在针对生产环境运行时，在Windows 7上的Chrome中看到了相同的行为。
服务器：
// Client <-> Host Protocol functions. Move to a different file so that they can be shared.
var C2H_SIGNAL_TYPE_REGISTER = "register";
var H2C_SIGNAL_WELCOME = "welcome";
var H2C_SIGNAL_TYPE_ERROR = "error";
var H2C_SIGNAL_TYPE_PEER_ADDED = "peer_joined";
var H2C_SIGNAL_TYPE_PEER_LEFT = "peer_left";
// Update channel endpoint names.
var UPDATE_ENDPOINT_PEERS = "/peers";
// Create a signal message with all asociated default properties.
// Signal senders should create this object and update it accordingly when
// building a signal message to send to a peer.
function createHostMsg(type)
{
var msg = { signalType: type };
if ( type == H2C_SIGNAL_WELCOME ) {
// Since we're sending a welcome message, we need to provide a list
// of currently connected clients.
msg.peers = {};
for ( var addr in clients ) {
console.log("addr " + addr);
var c = clients[addr].description;
if ( c && c.id ) {
msg.peers[c.id] = c;
}
}
}
return msg;
}
// require modules.
var express = require('express');
var http = require('http');
var bodyParser = require('body-parser');
var multer = require('multer');
// Tracks connected peers.
var clients = { };
// 1. Configure the application context settings.
var app = express();
app.enable('trust proxy');
app.use(express.static(__dirname + '/public'));
app.use(bodyParser.json()); // parse json
app.use(bodyParser.urlencoded({ extended: true })); // for parsing application/x-www-form-urlencoded
app.use(multer()); // for parsing multipart/form-data
// a. configure http routers. these will handle requests coming from app.
app.set('port', (process.env.PORT || 5000));
app.get('/app', peerApp);
app.get('/script/:name', publicScriptRouter);
// 2. Create the http server itself, passing app to be the request handler.
// app will handle routing and multiplexing of incoming requests to different
// route middleware handlers.
var http = require('http');
var WebSocketServer = require("ws").Server
var httpServer = http.createServer(app);
httpServer.listen( app.get('port') );
// 3. Create one of these for all socket endpoints.
var wss = new WebSocketServer( { server: httpServer, path: UPDATE_ENDPOINT_PEERS } );
wss.on("connection", function(webSocket) {
// 1. Associate the socket with the remote address it came from.
var remoteAddress = webSocket._socket.remoteAddress;
var remotePort = webSocket._socket.remotePort;
var clientConnID = remoteAddress + ":" + remotePort;
var exists = clients[clientConnID] != null;
if ( exists ) {
console.log("socket server connection: associating new connection from %s with registered peer.", clientConnID);
clients[clientConnID].socket = webSocket;
} else {
console.log("socket server connection: associating new connection from %s with unregistered peer.", clientConnID);
clients[clientConnID] = { description: null, socket: webSocket };
}
// 2. Hook up handlers for communication over this particular socket.
webSocket.on("message", function(data, flags) {
processMessage(webSocket, data, flags);
});
webSocket.on("close", function() {
// Praise satin for closures!!
removePeer(clientConnID);
});
});
// Transduce the message and handle it accordingly.
function processMessage(socket, data, flags)
{
var msg = JSON.parse(data);
if ( !msg.signalType ) {
var msg = createHostMsg( H2C_SIGNAL_TYPE_ERROR );
msg.errStr = "message_malformed";
socket.send( JSON.stringify( msg ) );
} else if ( msg.signalType == C2H_SIGNAL_TYPE_REGISTER ) {
handleRegistration(socket, msg);
}
}
客户端：
function initSignalChannel()
{
rtcPeer.channel = new WebSocket( location.origin.replace(/^http/, 'ws') + "/peers" );
rtcPeer.channel.onmessage = updateChannelMessage;
rtcPeer.channel.onopen = function(event) {
console.log("remote socket opened");
}
rtcPeer.channel.onclose = function(event) {
console.log("host closed remote socket.");
}
}
function updateChannelMessage(event) {
var msgObj = JSON.parse(event.data);
if ( !msgObj || !msgObj.signalType ) {
console.log("updateChannelMessage: malformed response!! %o", msgObj );
} else if ( msgObj.signalType == "welcome" ) {
console.log("updateChannelMessage: received welcome from host.");
handleWelcome(msgObj);
} else if ( msgObj.signalType == "peer_joined" ) {
console.log("updateChannelMessage: received peer_joined from host.");
if ( msgObj.peer.id == rtcPeer.description.id ) {
console.log("updateChannelMessage: peer_joined: received notification that I've been added to the room. " + msgObj.peer.id);
console.log(msgObj);
} else {
console.log("updateChannelMessage: peer_joined: peer %s is now online.", msgObj.peer.id);
console.log(msgObj);
addRemotePeer( msgObj.peer );
}
}
}
function addRemotePeer(peerObj)
{
remotePeers[peerObj.id] = peerObj;
var ui = createPeerUIObj(peerObj);
$("#connectedPeerList").append( ui );
}
function createPeerUIObj(peerObj)
{
var ui = null;
if ( peerObj ) {
ui = $("<li></li>");
var a = $("<a></a>");
a.append("peer " + peerObj.id);
ui.append(a);
ui.click(function(event) { console.log("clicked");});
}
return ui;
}
function handleWelcome(msgObj)
{
if ( msgObj.id ) {
console.log("updateChannelMessage: welcome: received id from host. " + msgObj.id);
console.log(msgObj);
rtcPeer.description.id = msgObj.id;
for ( var p in msgObj.peers ) {
addRemotePeer(msgObj.peers[p]);
}
} else {
console.log("updateChannelMessage: malformed response. no id.");
}
}
答案 0 :(得分：7)
感谢大家的评论。事实证明，jfriend00有正确的答案，我只是没有意识到我使用的托管服务不允许连接保持打开。
从以下论坛发帖，解决方案是
您需要定期让客户端ping服务器以使套接字保持活动状态。
不是最理想的情况，但确实可行。谢谢你指点我正确的方向。