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"use strict";
const RESOURCES_PATH = "/loading/early-hints/resources";
const SAME_ORIGIN_RESOURCES_URL = SAME_ORIGIN + RESOURCES_PATH;
const CROSS_ORIGIN_RESOURCES_URL = CROSS_ORIGIN + RESOURCES_PATH;
/**
* Navigate to a test page with an Early Hints response.
*
* @typedef {Object} Preload
* @property {string} url - A URL to preload. Note: This is relative to the
* `test_url` parameter of `navigateToTestWithEarlyHints()`.
* @property {string} as_attr - `as` attribute of this preload.
* @property {string} [crossorigin_attr] - `crossorigin` attribute of this
* preload.
*
* @param {string} test_url - URL of a test after the Early Hints response.
* @param {Array<Preload>} preloads - Preloads included in the Early Hints response.
*/
function navigateToTestWithEarlyHints(test_url, preloads) {
const params = new URLSearchParams();
params.set("test_url", test_url);
for (const preload of preloads) {
params.append("preloads", JSON.stringify(preload));
}
const url = "resources/early-hints-test-loader.h2.py?" + params.toString();
window.location.replace(new URL(url, window.location));
}
/**
* Parses the query string of the current window location and returns preloads
* in the Early Hints response sent via `navigateToTestWithEarlyHints()`.
*
* @returns {Array<Preload>}
*/
function getPreloadsFromSearchParams() {
const params = new URLSearchParams(window.location.search);
const encoded_preloads = params.getAll("preloads");
const preloads = [];
for (const encoded of encoded_preloads) {
preloads.push(JSON.parse(encoded));
}
return preloads;
}
/**
* Fetches a script or an image.
*
* @param {string} element - "script" or "img".
* @param {string} url - URL of the resource.
*/
async function fetchResource(element, url) {
return new Promise((resolve, reject) => {
const el = document.createElement(element);
el.src = url;
el.onload = resolve;
el.onerror = _ => reject(new Error("Failed to fetch resource: " + url));
document.body.appendChild(el);
});
}
/**
* Fetches a script.
*
* @param {string} url
*/
async function fetchScript(url) {
return fetchResource("script", url);
}
/**
* Fetches an image.
*
* @param {string} url
*/
async function fetchImage(url) {
return fetchResource("img", url);
}
/**
* Returns true when the resource is preloaded via Early Hints.
*
* @param {string} url
* @returns {boolean}
*/
function isPreloadedByEarlyHints(url) {
const entries = performance.getEntriesByName(url);
if (entries.length === 0) {
return false;
}
assert_equals(entries.length, 1);
return entries[0].initiatorType === "early-hints";
}
/**
* Navigate to the referrer policy test page.
*
* @param {string} referrer_policy - A value of Referrer-Policy to test.
*/
function testReferrerPolicy(referrer_policy) {
const params = new URLSearchParams();
params.set("referrer-policy", referrer_policy);
const same_origin_preload_url = SAME_ORIGIN_RESOURCES_URL + "/fetch-and-record-js.h2.py?id=" + token();
params.set("same-origin-preload-url", same_origin_preload_url);
const cross_origin_preload_url = CROSS_ORIGIN_RESOURCES_URL + "/fetch-and-record-js.h2.py?id=" + token();
params.set("cross-origin-preload-url", cross_origin_preload_url);
const path = "resources/referrer-policy-test-loader.h2.py?" + params.toString();
const url = new URL(path, window.location);
window.location.replace(url);
}
/**
* Navigate to the content security policy basic test. The test page sends an
* Early Hints response with a cross origin resource preload. CSP headers are
* configured based on the given policies. A policy should be one of the
* followings:
* "absent" - Do not send Content-Security-Policy header
* "allowed" - Set Content-Security-Policy to allow the cross origin preload
* "disallowed" - Set Content-Security-Policy to disallow the cross origin preload
*
* @param {string} early_hints_policy - The policy for the Early Hints response
* @param {string} final_policy - The policy for the final response
*/
function navigateToContentSecurityPolicyBasicTest(
early_hints_policy, final_policy) {
const params = new URLSearchParams();
params.set("resource-origin", CROSS_ORIGIN);
params.set("resource-url",
CROSS_ORIGIN_RESOURCES_URL + "/empty.js?" + token());
params.set("early-hints-policy", early_hints_policy);
params.set("final-policy", final_policy);
const url = "resources/csp-basic-loader.h2.py?" + params.toString();
window.location.replace(new URL(url, window.location));
}
/**
* Navigate to a test page which sends an Early Hints containing a cross origin
* preload link with/without Content-Security-Policy header. The CSP header is
* configured based on the given policy. The test page disallows the preload
* while the preload is in-flight. The policy should be one of the followings:
* "absent" - Do not send Content-Security-Policy header
* "allowed" - Set Content-Security-Policy to allow the cross origin preload
*
* @param {string} early_hints_policy
*/
function navigateToContentSecurityPolicyDocumentDisallowTest(early_hints_policy) {
const resource_id = token();
const params = new URLSearchParams();
params.set("resource-origin", CROSS_ORIGIN);
params.set("resource-url",
CROSS_ORIGIN_RESOURCES_URL + "/delayed-js.h2.py?id=" + resource_id);
params.set("resume-url",
CROSS_ORIGIN_RESOURCES_URL + "/resume-delayed-js.h2.py?id=" + resource_id);
params.set("early-hints-policy", early_hints_policy);
const url = "resources/csp-document-disallow-loader.h2.py?" + params.toString();
window.location.replace(new URL(url, window.location));
}
/**
* Navigate to a test page which sends different Cross-Origin-Embedder-Policy
* values in an Early Hints response and the final response.
*
* @param {string} early_hints_policy - The policy for the Early Hints response
* @param {string} final_policy - The policy for the final response
*/
function navigateToCrossOriginEmbedderPolicyMismatchTest(
early_hints_policy, final_policy) {
const params = new URLSearchParams();
params.set("resource-url",
CROSS_ORIGIN_RESOURCES_URL + "/empty-corp-absent.js?" + token());
params.set("early-hints-policy", early_hints_policy);
params.set("final-policy", final_policy);
const url = "resources/coep-mismatch.h2.py?" + params.toString();
window.location.replace(new URL(url, window.location));
}