131 lines
4.2 KiB
JavaScript
131 lines
4.2 KiB
JavaScript
/*
|
|
HTML5 Speedtest v4.7 MPOT - Server selector
|
|
by Federico Dossena
|
|
https://github.com/adolfintel/speedtest/
|
|
GNU LGPLv3 License
|
|
*/
|
|
|
|
//pings the specified URL, then calls the function result. Result will receive a parameter which is either the time it took to ping the URL, or -1 if something went wrong.
|
|
var PING_TIMEOUT = 1000;
|
|
var USE_PING_TIMEOUT = true; //will be disabled on unsupported browsers
|
|
if (/MSIE.(\d+\.\d+)/i.test(navigator.userAgent)) {
|
|
//IE11 doesn't support XHR timeout
|
|
USE_PING_TIMEOUT = false;
|
|
}
|
|
function ping(url, result) {
|
|
var xhr = new XMLHttpRequest();
|
|
var t = new Date().getTime();
|
|
xhr.onload = function() {
|
|
if (xhr.responseText.length == 0) {
|
|
//we expect an empty response
|
|
var instspd = new Date().getTime() - t; //rough timing estimate
|
|
try {
|
|
//try to get more accurate timing using performance API
|
|
var p = performance.getEntries();
|
|
p = p[p.length - 1];
|
|
var d = p.responseStart - p.requestStart;
|
|
if (d <= 0) d = p.duration;
|
|
if (d > 0 && d < instspd) instspd = d;
|
|
} catch (e) {}
|
|
result(instspd);
|
|
} else result(-1);
|
|
}.bind(this);
|
|
xhr.onerror = function() {
|
|
result(-1);
|
|
}.bind(this);
|
|
xhr.open("GET", url);
|
|
if (USE_PING_TIMEOUT) {
|
|
try {
|
|
xhr.timeout = PING_TIMEOUT;
|
|
xhr.ontimeout = xhr.onerror;
|
|
} catch (e) {}
|
|
}
|
|
xhr.send();
|
|
}
|
|
|
|
//this function repeatedly pings a server to get a good estimate of the ping. When it's done, it calls the done function without parameters. At the end of the execution, the server will have a new parameter called pingT, which is either the best ping we got from the server or -1 if something went wrong.
|
|
var PINGS = 3, //up to 3 pings are performed, unless the server is down...
|
|
SLOW_THRESHOLD = 500; //...or one of the pings is above this threshold
|
|
function checkServer(server, done) {
|
|
var i = 0;
|
|
server.pingT = -1;
|
|
if (server.server.indexOf(location.protocol) == -1) done();
|
|
else {
|
|
var nextPing = function() {
|
|
if (i++ == PINGS) {
|
|
done();
|
|
return;
|
|
}
|
|
ping(
|
|
server.server + server.pingURL,
|
|
function(t) {
|
|
if (t >= 0) {
|
|
if (t < server.pingT || server.pingT == -1) server.pingT = t;
|
|
if (t < SLOW_THRESHOLD) nextPing();
|
|
else done();
|
|
} else done();
|
|
}.bind(this)
|
|
);
|
|
}.bind(this);
|
|
nextPing();
|
|
}
|
|
}
|
|
|
|
/*this function goes through a list of servers, each with this format:
|
|
{
|
|
name: "User friendly name",
|
|
server:"http://yourBackend.com/", <---- make sure there's a / at the end!
|
|
dlURL:"garbage.php" <----- path to garbage.php or its replacement on the server
|
|
ulURL:"empty.php" <----- path to empty.php or its replacement on the server
|
|
pingURL:"empty.php" <----- path to empty.php or its replacement on the server. This is used to ping the server by this selector
|
|
getIpURL:"getIP.php" <----- path to getIP.php or its replacement on the server
|
|
}
|
|
For each server, the ping is measured, then the server with the function result is called with the best server, or null if all the servers were down.
|
|
*/
|
|
function selectServer(serverList, result) {
|
|
var i = 0;
|
|
var done = function() {
|
|
var bestServer = null;
|
|
for (var i = 0; i < serverList.length; i++) {
|
|
if (serverList[i].pingT != -1 && (bestServer == null || serverList[i].pingT < bestServer.pingT)) bestServer = serverList[i];
|
|
}
|
|
result(bestServer);
|
|
}.bind(this);
|
|
var nextServer = function() {
|
|
if (i == serverList.length) {
|
|
done();
|
|
return;
|
|
}
|
|
checkServer(serverList[i++], nextServer);
|
|
}.bind(this);
|
|
nextServer();
|
|
}
|
|
|
|
/*
|
|
this function is a faster version of selectServer that tests multiple servers concurrently. Useful for large server lists
|
|
*/
|
|
var CONCURRENCY = 4; //4 seems to be the safest value
|
|
function fastSelectServer(serverList, result) {
|
|
var serverLists = [];
|
|
for (var i = 0; i < CONCURRENCY; i++) {
|
|
serverLists[i] = [];
|
|
}
|
|
for (var i = 0; i < serverList.length; i++) {
|
|
serverLists[i % CONCURRENCY].push(serverList[i]);
|
|
}
|
|
var completed = 0;
|
|
var bestServer = null;
|
|
for (var i = 0; i < CONCURRENCY; i++) {
|
|
selectServer(
|
|
serverLists[i],
|
|
function(server) {
|
|
if (server != null) {
|
|
if (bestServer == null || server.pingT < bestServer.pingT) bestServer = server;
|
|
}
|
|
completed++;
|
|
if (completed == CONCURRENCY) result(bestServer);
|
|
}.bind(this)
|
|
);
|
|
}
|
|
}
|