/* 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
https://mozilla.org/MPL/2.0/. */
export var ManifestFinder = {
/**
* Check from content process if DOM Window has a conforming
* manifest link relationship.
* @param aContent DOM Window to check.
* @return {Promise<Boolean>}
*/
contentHasManifestLink(aContent) {
if (!aContent || isXULBrowser(aContent)) {
throw new TypeError("Invalid input.");
}
return checkForManifest(aContent);
},
/**
* Check from a XUL browser (parent process) if it's content document has a
* manifest link relationship.
* @param aBrowser The XUL browser to check.
* @return {Promise}
*/
async browserHasManifestLink(aBrowser) {
if (!isXULBrowser(aBrowser)) {
throw new TypeError("Invalid input.");
}
const actor =
aBrowser.browsingContext.currentWindowGlobal.getActor("ManifestMessages");
const reply = await actor.sendQuery("DOM:WebManifest:hasManifestLink");
return reply.result;
},
};
function isXULBrowser(aBrowser) {
if (!aBrowser || !aBrowser.namespaceURI || !aBrowser.localName) {
return false;
}
const XUL_NS =
"
http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul";
return aBrowser.namespaceURI === XUL_NS && aBrowser.localName === "browser";
}
function checkForManifest(aWindow) {
// Only top-level browsing contexts are valid.
if (!aWindow || aWindow.top !== aWindow) {
return false;
}
const elem = aWindow.document.querySelector("link[rel~='manifest']");
// Only if we have an element and a non-empty href attribute.
if (!elem || !elem.getAttribute("href")) {
return false;
}
return true;
}
