如何在 Node 中设置 http.request() 超时？

Question

我试图在使用 http.request 的 HTTP 客户端上设置超时，但没有成功。到目前为止我所做的是：

var options = { ... }
var req = http.request(options, function(res) {
  // Usual stuff: on(data), on(end), chunks, etc...
}

/* This does not work TOO MUCH... sometimes the socket is not ready (undefined) expecially on rapid sequences of requests */
req.socket.setTimeout(myTimeout);  
req.socket.on('timeout', function() {
  req.abort();
});

req.write('something');
req.end();

有什么提示吗？

Answer 1

在这里详细说明答案@douwe，您可以在 http 请求上设置超时。

// TYPICAL REQUEST
var req = https.get(http_options, function (res) {                                                                                                             
    var data = '';                                                                                                                                             

    res.on('data', function (chunk) { data += chunk; });                                                                                                                                                                
    res.on('end', function () {
        if (res.statusCode === 200) { /* do stuff with your data */}
        else { /* Do other codes */}
    });
});       
req.on('error', function (err) { /* More serious connection problems. */ }); 

// TIMEOUT PART
req.setTimeout(1000, function() {                                                                                                                              
    console.log("Server connection timeout (after 1 second)");                                                                                                                  
    req.abort();                                                                                                                                               
});

this.abort() 也可以。

Answer 2

对我来说 - 这是一种不太令人困惑的方法 socket.setTimeout

var request=require('https').get(
    url
   ,function(response){
        var r='';
        response.on('data',function(chunk){
            r+=chunk;
            });
        response.on('end',function(){
            console.dir(r);            //end up here if everything is good!
            });
        }).on('error',function(e){
            console.dir(e.message);    //end up here if the result returns an error
            });
request.on('error',function(e){
    console.dir(e);                    //end up here if a timeout
    });
request.on('socket',function(socket){
    socket.setTimeout(1000,function(){
        request.abort();                //causes error event ↑
        });
    });

Answer 3

您应该将引用传递给请求，如下所示

var options = { ... }
var req = http.request(options, function(res) {
  // Usual stuff: on(data), on(end), chunks, etc...
});

req.setTimeout(60000, function(){
    this.abort();
});
req.write('something');
req.end();

请求错误事件将被触发

req.on("error", function(e){
       console.log("Request Error : "+JSON.stringify(e));
  });

Answer 4

很好奇，如果直接使用 net.sockets 会发生什么？以下是我出于测试目的而整理的一些示例代码：

var net = require('net');

function HttpRequest(host, port, path, method) {
  return {
    headers: [],
    port: 80,
    path: "/",
    method: "GET",
    socket: null,
    _setDefaultHeaders: function() {

      this.headers.push(this.method + " " + this.path + " HTTP/1.1");
      this.headers.push("Host: " + this.host);
    },
    SetHeaders: function(headers) {
      for (var i = 0; i < headers.length; i++) {
        this.headers.push(headers[i]);
      }
    },
    WriteHeaders: function() {
      if(this.socket) {
        this.socket.write(this.headers.join("\r\n"));
        this.socket.write("\r\n\r\n"); // to signal headers are complete
      }
    },
    MakeRequest: function(data) {
      if(data) {
        this.socket.write(data);
      }

      this.socket.end();
    },
    SetupRequest: function() {
      this.host = host;

      if(path) {
        this.path = path;
      }
      if(port) {
        this.port = port;
      }
      if(method) {
        this.method = method;
      }

      this._setDefaultHeaders();

      this.socket = net.createConnection(this.port, this.host);
    }
  }
};

var request = HttpRequest("www.somesite.com");
request.SetupRequest();

request.socket.setTimeout(30000, function(){
  console.error("Connection timed out.");
});

request.socket.on("data", function(data) {
  console.log(data.toString('utf8'));
});

request.WriteHeaders();
request.MakeRequest();

Answer 5

2019 更新

现在有多种方法可以更优雅地处理这个问题。请参阅此线程上的一些其他答案。技术发展很快，因此答案往往很快就会过时。我的答案仍然有效，但也值得考虑替代方案。

2012 答案

使用您的代码，问题是您在尝试在套接字对象上设置内容之前没有等待将套接字分配给请求。这都是异步的：

var options = { ... }
var req = http.request(options, function(res) {
  // Usual stuff: on(data), on(end), chunks, etc...
});

req.on('socket', function (socket) {
    socket.setTimeout(myTimeout);  
    socket.on('timeout', function() {
        req.abort();
    });
});

req.on('error', function(err) {
    if (err.code === "ECONNRESET") {
        console.log("Timeout occurs");
        //specific error treatment
    }
    //other error treatment
});

req.write('something');
req.end();

当请求被分配一个套接字对象时，会触发“socket”事件。

Answer 6

只是为了澄清上面的答案：

现在可以使用timeout选项和相应的请求事件：

// set the desired timeout in options
const options = {
    //...
    timeout: 3000,
};

// create a request
const request = http.request(options, response => {
    // your callback here
});

// use its "timeout" event to abort the request
request.on('timeout', () => {
    request.destroy();
});

请参阅文档：

Answer 7

此时有一个方法可以直接在请求对象上执行此操作：

request.setTimeout(timeout, function() {
    request.abort();
});

这是绑定到套接字事件然后创建超时的快捷方法。

参考： Node.js v0.8.8 手册&文档

Answer 8

Rob Evans anwser 对我来说工作正常，但是当我使用 request.abort() 时，它会抛出一个未处理的套接字挂起错误。

我必须为请求对象添加一个错误处理程序：

var options = { ... }
var req = http.request(options, function(res) {
  // Usual stuff: on(data), on(end), chunks, etc...
}

req.on('socket', function (socket) {
    socket.setTimeout(myTimeout);  
    socket.on('timeout', function() {
        req.abort();
    });
}

req.on('error', function(err) {
    if (err.code === "ECONNRESET") {
        console.log("Timeout occurs");
        //specific error treatment
    }
    //other error treatment
});

req.write('something');
req.end();

Answer 9

还有更简单的方法。

不使用 setTimeout 或直接使用套接字，
我们可以在客户端使用的“选项”中使用“超时”。

下面是服务器和客户端的代码，分为3部分。

模块和选项部分：

'use strict';

// Source: https://github.com/nodejs/node/blob/master/test/parallel/test-http-client-timeout-option.js

const assert = require('assert');
const http = require('http');

const options = {
    host: '127.0.0.1', // server uses this
    port: 3000, // server uses this

    method: 'GET', // client uses this
    path: '/', // client uses this
    timeout: 2000 // client uses this, timesout in 2 seconds if server does not respond in time
};

服务器部分：

function startServer() {
    console.log('startServer');

    const server = http.createServer();
    server
            .listen(options.port, options.host, function () {
                console.log('Server listening on http://' + options.host + ':' + options.port);
                console.log('');

                // server is listening now
                // so, let's start the client

                startClient();
            });
}

客户端部分：

function startClient() {
    console.log('startClient');

    const req = http.request(options);

    req.on('close', function () {
        console.log("got closed!");
    });

    req.on('timeout', function () {
        console.log("timeout! " + (options.timeout / 1000) + " seconds expired");

        // Source: https://github.com/nodejs/node/blob/master/test/parallel/test-http-client-timeout-option.js#L27
        req.destroy();
    });

    req.on('error', function (e) {
        // Source: https://github.com/nodejs/node/blob/master/lib/_http_outgoing.js#L248
        if (req.connection.destroyed) {
            console.log("got error, req.destroy() was called!");
            return;
        }

        console.log("got error! ", e);
    });

    // Finish sending the request
    req.end();
}


startServer();

如果将以上 3 部分全部放在一个文件“a.js”中，然后运行：

node a.js

那么，输出将是：

startServer
Server listening on http://127.0.0.1:3000

startClient
timeout! 2 seconds expired
got closed!
got error, req.destroy() was called!

希望有帮助。