Source code
Revision control
Copy as Markdown
Other Tools
/* 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
const lazy = {};
ChromeUtils.defineESModuleGetters(lazy, {
NetworkHelper:
});
/**
* Global cache session object.
*/
let gCacheSession = null;
/**
* Get (and create if necessary) a cache session / cache storage session.
*
* @param {nsIRequest} request
*/
function getCacheSession(request) {
if (!gCacheSession) {
try {
const cacheService = Services.cache2;
if (cacheService) {
let loadContext = lazy.NetworkHelper.getRequestLoadContext(request);
if (!loadContext) {
// Get default load context if we can't fetch.
loadContext = Services.loadContextInfo.default;
}
gCacheSession = cacheService.diskCacheStorage(loadContext);
}
} catch (e) {
gCacheSession = null;
}
}
return gCacheSession;
}
/**
* Parses a cache entry returned from the backend to build a response cache
* object.
*
* @param {nsICacheEntry} cacheEntry
* The cache entry from the backend.
*
* @returns {Object}
* A responseCache object expected by RDP.
*/
function buildResponseCacheObject(cacheEntry) {
const cacheObject = {};
try {
if (cacheEntry.storageDataSize) {
cacheObject.storageDataSize = cacheEntry.storageDataSize;
}
} catch (e) {
// We just need to handle this in case it's a js file of 0B.
}
if (cacheEntry.expirationTime) {
cacheObject.expirationTime = cacheEntry.expirationTime;
}
if (cacheEntry.fetchCount) {
cacheObject.fetchCount = cacheEntry.fetchCount;
}
if (cacheEntry.lastFetched) {
cacheObject.lastFetched = cacheEntry.lastFetched;
}
if (cacheEntry.lastModified) {
cacheObject.lastModified = cacheEntry.lastModified;
}
if (cacheEntry.deviceID) {
cacheObject.deviceID = cacheEntry.deviceID;
}
return cacheObject;
}
/**
* Does the fetch for the cache entry from the session.
*
* @param {nsIRequest} request
* The request object.
*
* @returns {Promise}
* Promise which resolve a response cache object object, or null if none
* was available.
*/
export function getResponseCacheObject(request) {
const cacheSession = getCacheSession(request);
if (!cacheSession) {
return null;
}
return new Promise(resolve => {
cacheSession.asyncOpenURI(
request.URI,
"",
Ci.nsICacheStorage.OPEN_SECRETLY,
{
onCacheEntryCheck: () => {
return Ci.nsICacheEntryOpenCallback.ENTRY_WANTED;
},
onCacheEntryAvailable: cacheEntry => {
if (cacheEntry) {
const cacheObject = buildResponseCacheObject(cacheEntry);
resolve(cacheObject);
} else {
resolve(null);
}
},
}
);
});
}