stress-test.js

var debug   = require('debug')('stress-test');
var request = require('request');

request.defaults({ timeout: 500 });

var haproxy = undefined;

var do_request = function(id) {
    var start_time = process.hrtime();
    request.get('http://echo.service.my_company.com', function(err, res, body) {
        var diff_time = process.hrtime(start_time);
        var duration = (diff_time[0] * 1000 + diff_time[1] / 10000000) | 0;
        if(err) {
            debug('%s: request error: %s, duration: %s', id, err, duration);
        } else if(res.statusCode != 200) {
            debug('%s: status: %s, duration: %s', id, res.statusCode, duration);
        } else {
            var data = JSON.parse(body);
            var h = data.remoteAddress;
{ //            if((duration >= 100) || (haproxy !== h)) {
                haproxy = h;
                debug('%s: remote address: %s, service host: %s, duration: %s', id, h, res.headers['x-bla-host'], duration);
            }
        }

        // tail recursion
        setTimeout(function() { do_request(id) }, Math.random() * 10);
    });
};

for(var i = 0; i < 10; ++i) {
    do_request(i);
}