Question

我有一个用NodeJS编写的简单且有效的Web服务器，如下所示：

var http = require("http");
var fs = require("fs");

console.log("Web server started");
var config = JSON.parse(fs.readFileSync("./private/config.json"));

var server = http.createServer(function(req,res){

    console.log("received request: " + req.url);
    fs.readFile("./public" + req.url,function(error,data){

        if (error){

            // Not sure if this is a correct way to set the default page? 
            if (req.url === "/"){
                res.writeHead(200,{"content-type":"text/plain"});
                res.end("here goes index.html ?");
            }

            res.writeHead(404,{"content-type":"text/plain"});
            res.end(`Sorry the page was not found.\n URL Request: ${req.url}`);
        } else {
            res.writeHead(200,{"content-type":"text/plain"});
            res.end(data);
        }

    });
});

现在，当配置文件中的端口号发生变化时，我希望我的Web服务器重新启动并侦听新端口。所以我在下面添加代码：

fs.watch("./private/config.json",function(){
    config = JSON.parse(fs.readFileSync("./private/config.json"))
    server.close();
    server.listen(config.port,config.host,function(){
        console.log("Now listening: "+config.host+ ":" +config.port);
    });
});

这很好用，当我更改配置文件上的端口时，我可以在新端口上访问我的Web服务器。但是，我也可以在之前的端口上访问它。在我收听新端口之前，我以为我正在关闭上一个端口上的Web服务器。我错过了什么？

感谢您的帮助:)

Answer 1

正如Mukesh Sharma所说，Server.close（）停止接受新连接并保持现有连接。也就是说，服务器对所有活动套接字保持打开状态（直到它们因保持活动时间而自然死亡），但不会创建新的套接字。

我发现这个问题可能是this question

的重复

所以我按照Golo Roden在链接中提到的建议解决方案进行操作。基本上，您需要记住打开套接字连接并在关闭服务器后销毁它们。这是我修改过的代码：

var http = require("http");
var fs = require("fs");

console.log("Web server started");
var config = JSON.parse(fs.readFileSync("./private/config.json"));

var server = http.createServer(function(req,res){

    console.log("received request: " + req.url);
    fs.readFile("./public" + req.url,function(error,data){

        if (error){

            // Not sure if this the correct method ? 
            if (req.url === "/"){
                res.writeHead(200,{"content-type":"text/plain"});
                res.end("welcome to main page");
            }

            res.writeHead(404,{"content-type":"text/plain"});
            res.end(`Sorry the page was not found.\n URL Request: ${req.url}`);
        } else {
            res.writeHead(200,{"content-type":"text/plain"});
            res.end(data);
        }

    });
});

server.listen(config.port,config.host,function(){
    console.log("listening: "+config.host+ ":" +config.port);
});

var sockets = {}, nextSocketId = 0;
server.on('connection', function (socket) {

  // Add a newly connected socket
  var socketId = nextSocketId++;
  sockets[socketId] = socket;
  console.log('socket', socketId, 'opened');

  // Remove the socket when it closes
  socket.on('close', function () {
    console.log('socket', socketId, 'closed');
    delete sockets[socketId];
  });

});

fs.watch("./private/config.json",function(){
    config = JSON.parse(fs.readFileSync("./private/config.json"))
    console.log('Config has changed!'); 
    server.close(function () { console.log('Server is closing!');  });

    for (var socketId in sockets) {
        console.log('socket', socketId, 'destroyed');
        sockets[socketId].destroy();
    }

    server.listen(config.port,config.host,function(){
    console.log("Now listening: "+config.host+ ":" +config.port);
    });
});

使用NodeJS更改配置文件时重新启动Web服务器

1 个答案: