使用nodejs更改配置文件时，重新启动Web服务器

Question

我有一个简单且有效的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，我希望我的Web服务器重新启动并在配置文件中更改端口号时收听新端口。因此，我在下面添加了代码：

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);
    });
});

这可以正常工作，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，我也可以在上一个端口上访问它。我以为在收听新端口之前，我将关闭上一个端口上的Web服务器。我想念什么？

我感谢您的帮助:)

Answer 1

如Mukesh Sharma所述，Server.Close（）停止接受新的连接并保持现有连接。也就是说，服务器对所有活着的插座都保持开放（直到它们自然会因保持时间而死），但不会创建新的插座。

我发现这个问题可能是这个问题的重复

因此，我遵循了Golo Roden在链接中提到的建议解决方案。基本上，您需要记住打开的套接字连接并在关闭服务器后破坏它们。这是我修改的代码：

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);
    });
});