KeepAlive test stand

keepalive_test.js

const url = process.argv[2];
const concurrency = process.argv[3] === undefined ? 1 : parseInt(process.argv[3]);
const requestInterval = process.argv[4] === undefined ? 10000 : parseInt(process.argv[4]);

if (url === undefined || isNaN(concurrency) || isNaN(requestInterval)) {
    console.log('Usage: node keepalive_test.js http://google.com/ 10 10000');
    console.log('Where: 2nd - URL');
    console.log('       3rd - amount of concurrent connections (default is 1)');
    console.log('       4rd - interval between sequential requests');
    process.exit();
}

const http = require('http');

const keepAliveAgent = new http.Agent({
    keepAlive: true,
    keepAliveMsecs: 60000,
    maxSockets: 5
});

let globalRequestNo = 0;

function start(concurrency, timeout) {
    for (let i = 0; i < concurrency; i++) {
        makeRequest().then(
            () => scheduleNextRequest(timeout),
            () => scheduleNextRequest(timeout)
        );
    }
}

function scheduleNextRequest(timeout) {
    setTimeout(() => {
        makeRequest().then(
            () => scheduleNextRequest(timeout),
            () => scheduleNextRequest(timeout)
        );
    }, timeout);
}

function makeRequest() {
    return new Promise((resolve, reject) => {
        let requestNo = globalRequestNo++;

        console.log(`REQUEST ${requestNo}: starting`);
        const options = {method: 'GET', agent: keepAliveAgent};

        const req = http.request(url, options, res => {
            res.on('data', chunk => {console.log(`BODY: ${chunk}`);});
            res.on('end', () => {
                console.log(`REQUEST ${requestNo}: finished`);
                return resolve();
            });
            req.on('error', e => {
                console.log(`REQUEST ${requestNo}: ${e.toMessage()}`);
                return reject(e);
            });
        });

        req.end();
    });
}

start(concurrency, requestInterval);