mirror of https://github.com/flutter/samples.git
You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
48 lines
1.6 KiB
48 lines
1.6 KiB
// Copyright 2021 The Flutter team. All rights reserved.
|
|
// Use of this source code is governed by a BSD-style license that can be
|
|
// found in the LICENSE file.
|
|
|
|
// Helper class to capture Flutter web app startup timing information
|
|
class FlutterWebStartupAnalyzer {
|
|
timings;
|
|
|
|
constructor() {
|
|
this.timings = {};
|
|
}
|
|
|
|
markStart(name) {
|
|
this.timings[name] = null;
|
|
performance.mark('flt-' + name + '-started');
|
|
}
|
|
markFinished(name) {
|
|
performance.mark('flt-' + name + '-finished');
|
|
}
|
|
capture(name) {
|
|
var timingName = 'flt-' + name;
|
|
var started = 'flt-' + name + 'started';
|
|
try {
|
|
var measurement = performance.measure('flt-' + name, 'flt-' + name + '-started', 'flt-' + name + '-finished');
|
|
} catch(e) {
|
|
// ignore errors if the mark doesn't exist
|
|
return;
|
|
}
|
|
this.timings[name] = measurement.duration;
|
|
}
|
|
captureAll() {
|
|
for (var [key, value] of Object.entries(this.timings)) {
|
|
this.capture(key);
|
|
}
|
|
// Capture
|
|
this.timings['load'] = performance.timing.loadEventEnd - performance.timing.domContentLoadedEventEnd;
|
|
this.timings['domContentLoaded'] = performance.timing.domContentLoadedEventEnd - performance.timing.navigationStart;
|
|
}
|
|
|
|
capturePaint() {
|
|
const entries = performance.getEntriesByType("paint");
|
|
// Collect first-paint and first-contentful-paint entries
|
|
entries.forEach((entry) => {
|
|
this.timings[entry.name] = entry.startTime;
|
|
});
|
|
}
|
|
}
|