/* Copyright 2023 Google LLC. SPDX-License-Identifier: Apache-2.0 */ const logEl = document.getElementById('log'); function log(message) { console.log(message); logEl.innerHTML += '
' + message + '<\p>';
}
log(`HTML meta tag in this page includes a trial token`);
const otMetaTag = document.querySelector('meta[http-equiv="origin-trial"]');
const token = otMetaTag.getAttribute('content');
const decodedToken = decodeToken(token)
const expiryDate = new Date(decodedToken.payload.expiry * 1000);
const feature = decodedToken.payload.feature;
const isThirdParty = decodedToken.payload.isThirdParty;
const tokenOrigin = decodedToken.payload.origin;
// Check if the origin trial feature is available.
// This will only work if the trial is current, and the token is valid and used correctly.
// This demo currently uses a token for the WebSQL deprecation trial: https://developer.chrome.com/origintrials/#/view_trial/3977804370874990593
function isTrialFeatureEnabled() {
return !! ('openDatabase' in window);
}
async function accessTrialFeature() {
log(`Token feature: ${feature}`);
log(`Token registered for origin: ${tokenOrigin}`);
log(isThirdParty ? `Token is third-party` : `Token is not third-party`);
log(`Token expiry date:
${expiryDate}`);
log('/js/main.js is attempting to access the trial feature...');
isTrialFeatureEnabled() ?
log(`Trial feature ${feature} is available 😺`) :
log(`Trial feature ${feature} is not available 😿`);
}
try {
accessTrialFeature();
} catch (error) {
log('Error attempting to access trial feature:', error);
}
// Code adapted from https://github.com/Jxck/origin-trials-viewer/blob/main/util.js
function base64decode(str) {
return new Uint8Array([...atob(str)].map(a => a.charCodeAt(0)));
}
function decodeToken(token) {
const buf = base64decode(token);
const view = new DataView(buf.buffer)
const version = view.getUint8()
const signature = buf.slice(1, 65)
const length = view.getUint32(65, false)
const payload = JSON.parse((new TextDecoder()).decode(buf.slice(69, 69 + length)))
return {payload, version, length, signature}
}