如何在Node中的http.request()上设置超时？

Question

我正在尝试在没有运气的情况下使用http.request的HTTP客户端设置超时.到目前为止我所做的是这样的:

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();

任何提示？

Answer 1

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.这一切都是异步的:

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();

在为请求分配套接字对象时会触发'socket'事件.

Answer 2

此时有一种方法可以直接在请求对象上执行此操作:

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

这是一种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手册和文档

Answer 3

Rob Evans anwser对我来说正常工作,但是当我使用request.abort()时,会发生一个套接字挂起错误,它仍然未处理.

我不得不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 4

只是为了澄清以上答案：

现在可以使用timeoutoption和相应的request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.abort();
});

Answer 5

有更简单的方法.

我们可以在客户端使用的'options'中使用'timeout',而不是使用setTimeout或直接使用套接字

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();

如果将上述3个部分放在一个文件"a.js"中,然后运行:

node a.js

然后,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!

希望有所帮助.