1234567891011121314151617181920212223242526272829303132333435363738394041424344454647484950515253545556575859606162636465666768 |
- /*
- * Copyright 2020 Google LLC
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * https://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
- import { bindReporter } from './lib/bindReporter.js';
- import { finalMetrics } from './lib/finalMetrics.js';
- import { getFirstHidden } from './lib/getFirstHidden.js';
- import { initMetric } from './lib/initMetric.js';
- import { observe } from './lib/observe.js';
- import { onBFCacheRestore } from './lib/onBFCacheRestore.js';
- import { onHidden } from './lib/onHidden.js';
- import { firstInputPolyfill, resetFirstInputPolyfill } from './lib/polyfills/firstInputPolyfill.js';
- export const getFID = (onReport, reportAllChanges) => {
- const firstHidden = getFirstHidden();
- let metric = initMetric('FID');
- let report;
- const entryHandler = (entry) => {
- // Only report if the page wasn't hidden prior to the first input.
- if (entry.startTime < firstHidden.timeStamp) {
- metric.value = entry.processingStart - entry.startTime;
- metric.entries.push(entry);
- finalMetrics.add(metric);
- report();
- }
- };
- const po = observe('first-input', entryHandler);
- report = bindReporter(onReport, metric, reportAllChanges);
- if (po) {
- onHidden(() => {
- po.takeRecords().map(entryHandler);
- po.disconnect();
- }, true);
- }
- if (self.__WEB_VITALS_POLYFILL__) {
- // Prefer the native implementation if available,
- if (!po) {
- window.webVitals.firstInputPolyfill(entryHandler);
- }
- onBFCacheRestore(() => {
- metric = initMetric('FID');
- report = bindReporter(onReport, metric, reportAllChanges);
- window.webVitals.resetFirstInputPolyfill();
- window.webVitals.firstInputPolyfill(entryHandler);
- });
- }
- else {
- // Only monitor bfcache restores if the browser supports FID natively.
- if (po) {
- onBFCacheRestore(() => {
- metric = initMetric('FID');
- report = bindReporter(onReport, metric, reportAllChanges);
- resetFirstInputPolyfill();
- firstInputPolyfill(entryHandler);
- });
- }
- }
- };
|