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// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this
// file, You can obtain one at http://mozilla.org/MPL/2.0/.
/* eslint-env node */
/*
Ensure the `--firefox.preference=network.http.http3.enable:true` is
set for this test.
*/
async function getNumImagesLoaded(elementSelector, commands) {
return commands.js.run(`
let sum = 0;
document.querySelectorAll(${elementSelector}).forEach(e => {
sum += e.complete & e.naturalHeight != 0;
});
return sum;
`);
}
async function waitForImgLoadEnd(
prevCount,
maxStableCount,
iterationDelay,
timeout,
commands,
context,
counter,
elementSelector
) {
let starttime = await commands.js.run(`return performance.now();`);
let endtime = await commands.js.run(`return performance.now();`);
let changing = true;
let newCount = -1;
let stableCount = 0;
while (
((await commands.js.run(`return performance.now();`)) - starttime <
timeout) &
changing
) {
// Wait a bit before making another round
await commands.wait.byTime(iterationDelay);
newCount = await counter(elementSelector, commands);
context.log.debug(`${newCount}, ${prevCount}, ${stableCount}`);
// Check if we are approaching stability
if (newCount == prevCount) {
// Gather the end time now
if (stableCount == 0) {
endtime = await commands.js.run(`return performance.now();`);
}
stableCount++;
} else {
prevCount = newCount;
stableCount = 0;
}
if (stableCount >= maxStableCount) {
// Stability achieved
changing = false;
}
}
return {
start: starttime,
end: endtime,
numResources: newCount,
};
}
async function test(context, commands) {
let rootUrl = "https://www.google.com/search?q=kittens&tbm=isch";
let waitTime = 1000;
let numScrolls = 10;
const average = arr => arr.reduce((p, c) => p + c, 0) / arr.length;
if (typeof context.options.browsertime !== "undefined") {
if (typeof context.options.browsertime.waitTime !== "undefined") {
waitTime = context.options.browsertime.waitTime;
}
if (typeof context.options.browsertime.numScrolls !== "undefined") {
numScrolls = context.options.browsertime.numScrolls;
}
}
// Make firefox learn of HTTP/3 server
await commands.navigate(rootUrl);
let cycles = 1;
for (let cycle = 0; cycle < cycles; cycle++) {
// Measure the pageload
await commands.measure.start("pageload");
await commands.navigate(rootUrl);
await commands.measure.stop();
async function getHeight() {
return commands.js.run(`return document.body.scrollHeight;`);
}
let vals = [];
let badIterations = 0;
let prevHeight = 0;
for (let iteration = 0; iteration < numScrolls; iteration++) {
// Get current image count
let currCount = await getNumImagesLoaded(`".isv-r img"`, commands);
prevHeight = await getHeight();
// Scroll to a ridiculously high value for "infinite" down-scrolling
commands.js.runAndWait(`
window.scrollTo({ top: 100000000 })
`);
/*
The maxStableCount of 22 was chosen as a trade-off between fast iterations
and minimizing the number of bad iterations.
*/
let results = await waitForImgLoadEnd(
currCount,
22,
100,
120000,
commands,
context,
getNumImagesLoaded,
`".isv-r img"`
);
// Gather metrics
let ndiff = results.numResources - currCount;
let tdiff = (results.end - results.start) / 1000;
// Check if we had a bad iteration
if (ndiff == 0) {
// Check if the end of the search results was reached
if (prevHeight == (await getHeight())) {
context.log.info("Reached end of page.");
break;
}
context.log.info("Bad iteration, redoing...");
iteration--;
badIterations++;
if (badIterations == 5) {
throw new Error("Too many bad scroll iterations occurred");
}
continue;
}
context.log.info(`${ndiff}, ${tdiff}`);
vals.push(ndiff / tdiff);
// Wait X seconds before scrolling again
await commands.wait.byTime(waitTime);
}
if (!vals.length) {
throw new Error("No requestsPerSecond values were obtained");
}
commands.measure.result[0].browserScripts.pageinfo.imagesPerSecond =
average(vals);
// Test clicking and and opening an image
await commands.wait.byTime(waitTime);
commands.click.byJs(`
const links = document.querySelectorAll(".islib"); links[links.length-1]
`);
let results = await waitForImgLoadEnd(
0,
22,
50,
120000,
commands,
context,
getNumImagesLoaded,
`"#islsp img"`
);
commands.measure.result[0].browserScripts.pageinfo.imageLoadTime =
results.end - results.start;
}
}
module.exports = {
test,
owner: "Network Team",
component: "netwerk",
name: "g-image",
description: "Measures the number of images per second after a scroll.",
};
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