Very simple load tester for MediaWiki

simple-load-test.js

window.data = {};
window.lastUid = null;
window.cooldown = 0;
window.pending = {};

function requestPage ( interval, loadTestEnd ) {
	
	// var milliseconds = Date.now();
	var uid = makeid();
	window.data[uid] = {
		uid: uid,
		start: Date.now(),
		end: null,
		duration: null,
		title: ""
	};

	window.lastUid = uid;
	window.pending[uid] = true;
	$.get(
		"/eva/index.php/Special:Random",
		{},
		function( resp ){
			
			// remove this one from pending
			window.pending[uid]
			delete window.pending[uid];

			var end = Date.now(),
				duration = end - window.data[uid].start;

			window.data[uid].end = end;
			window.data[uid].duration = duration;
			var title = resp.match( /<title>(.*?)<\/title>/ );
			window.data[uid].title = title && title[1] ? title[1] : "Title read failed";
			window.data[uid].interval = interval;

			console.log(
				JSON.stringify({
					duration: duration,
					interval: interval,
					remaining_seconds: parseInt( ( loadTestEnd - Date.now() ) / 1000 ),
					allTestRequestsSent: allTestRequestsSent,
					lastUid: lastUid,
					uid: uid
				})
			);

			// controller (loadTest method) has determined test is complete
			// and there are no more pending requests
			if ( allTestRequestsSent === true && Object.keys(window.pending).length === 0 ) {
				console.log( "Complete with final request for this test" );
				loadNextTest();
			}

			if ( window.lastUid === uid ) {
				window.lastUid = null;
			}

		}
	);

	return uid;
}

function makeid () {

    var text = "";
    var possible = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";

    for( var i=0; i < 20; i++ )
        text += possible.charAt(Math.floor(Math.random() * possible.length));

    return text;
}

function loadTest ( interval, duration ) {

	var interval = interval || 500, // default 500ms
		duration = duration || 60, // default 60 seconds
		durationMS = parseInt( duration * 1000 ); // duration in seconds * 1000 ms/sec
	
	window.loadTestStart = Date.now();
	window.loadTestEnd = loadTestStart + durationMS;

	console.log(  "Starting test\n" 
				+ "-------------\n"
				+ "  Interval: " + interval + " milliseconds\n"
				+ "  Duration: " + duration + " seconds\n"
	);

	// fire one off now, before doing setInteval
	requestPage( interval );
	
	window.intervalID = setInterval( function() {

		if ( Date.now() < loadTestEnd ) {
			requestPage( interval, loadTestEnd );
		}
		else {

			clearInterval( window.intervalID );

			// test has ended, and last request has already responded
			if ( ! window.lastUid ) {
				loadNextTest();
			}
			// make the final request wrap things up
			else {
				window.allTestRequestsSent = true;
			}

		}

	}, interval );

}

function loadTests ( tests ) {
	window.loadTests = tests;
	loadNextTest();
}

function loadNextTest () {
	window.allTestRequestsSent = false;

	if ( window.loadTests.length ) {

		var test = window.loadTests.shift();
		
		var interval = test.interval || 500, // default 500ms
			duration = test.duration || 60; // default 60 seconds

		console.log( "Starting new test in " + window.cooldown + " seconds" );

		setTimeout( function () {
			loadTest( interval, duration );
		}, window.cooldown * 1000 );

		window.cooldown = test.cooldown || window.cooldown;
	}
	else {
		console.log( "ALL LOAD TESTS COMPLETE" );
		console.log( testSerialize() );
	}
}

function testSerialize () {

	var serial = [];
	for ( var t in window.data ) {
		serial.push( window.data[t] );
	}

	serial.sort( function( a, b ) {
		return a.start - b.start;
	});

	var output = "Start\tDuration\tInterval\tTitle",
		start;
	for ( var t = 0; t < serial.length; t++ ) {
		start = new Date( serial[t].start );
		start = [
			pad( start.getHours() ),
			pad( start.getMinutes() ),
			pad( start.getSeconds() )
		].join(":");
		output += "\n" 
			+ [
				start,
				serial[t].duration,
				serial[t].interval,
				serial[t].title
			].join("\t");
	}

	return output;
}

function pad( n, width, z ) {
	z = z || '0';
	n = n + '';
	width = width || 2;
	return n.length >= width ? n : new Array(width - n.length + 1).join(z) + n;
}


loadTests([
	{ interval: 600, duration: 180, cooldown: 30 },
	{ interval: 550, duration: 180, cooldown: 30 },
	{ interval: 500, duration: 180, cooldown: 30 },
	{ interval: 450, duration: 180, cooldown: 30 },
	{ interval: 400, duration: 180, cooldown: 30 },
	{ interval: 350, duration: 180, cooldown: 30 }
]);