gecko-dev/devtools/shared/platform/cache-entry.js

118 строки
3.5 KiB
JavaScript

/* -*- indent-tabs-mode: nil; js-indent-level: 2 -*- */
/* vim: set ft= javascript ts=2 et sw=2 tw=80: */
/* 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 http://mozilla.org/MPL/2.0/. */
"use strict";
const Services = require("Services");
const {Ci} = require("chrome");
loader.lazyRequireGetter(this, "NetworkHelper",
"devtools/shared/webconsole/network-helper");
/**
* Module to fetch cache objects from CacheStorageService
* and return them as an object.
*/
exports.CacheEntry = {
/**
* Flag for cache session being initialized.
*/
isCacheSessionInitialized: false,
/**
* Cache session object.
*/
cacheSession: null,
/**
* Initializes our cache session / cache storage session.
*/
initializeCacheSession: function(request) {
try {
const cacheService = Services.cache2;
if (cacheService) {
let loadContext = NetworkHelper.getRequestLoadContext(request);
if (!loadContext) { // Get default load context if we can't fetch.
loadContext = Services.loadContextInfo.default;
}
this.cacheSession =
cacheService.diskCacheStorage(loadContext, false);
this.isCacheSessionInitialized = true;
}
} catch (e) {
this.isCacheSessionInitialized = false;
}
},
/**
* Parses a cache descriptor returned from the backend into a
* usable object.
*
* @param Object descriptor The descriptor from the backend.
*/
parseCacheDescriptor: function(descriptor) {
const descriptorObj = {};
try {
if (descriptor.storageDataSize) {
descriptorObj.dataSize = descriptor.storageDataSize;
}
} catch (e) {
// We just need to handle this in case it's a js file of 0B.
}
if (descriptor.expirationTime) {
descriptorObj.expires = descriptor.expirationTime;
}
if (descriptor.fetchCount) {
descriptorObj.fetchCount = descriptor.fetchCount;
}
if (descriptor.lastFetched) {
descriptorObj.lastFetched = descriptor.lastFetched;
}
if (descriptor.lastModified) {
descriptorObj.lastModified = descriptor.lastModified;
}
if (descriptor.deviceID) {
descriptorObj.device = descriptor.deviceID;
}
return descriptorObj;
},
/**
* Does the fetch for the cache descriptor from the session.
*
* @param string request
* The request object.
* @param Function onCacheDescriptorAvailable
* callback function.
*/
getCacheEntry: function(request, onCacheDescriptorAvailable) {
if (!this.isCacheSessionInitialized) {
this.initializeCacheSession(request);
}
if (this.cacheSession) {
const uri = NetworkHelper.nsIURL(request.URI.spec);
this.cacheSession.asyncOpenURI(
uri,
"",
Ci.nsICacheStorage.OPEN_SECRETLY,
{
onCacheEntryCheck: (entry, appcache) => {
return Ci.nsICacheEntryOpenCallback.ENTRY_WANTED;
},
onCacheEntryAvailable: (descriptor, isnew, appcache, status) => {
if (descriptor) {
const descriptorObj = this.parseCacheDescriptor(descriptor);
onCacheDescriptorAvailable(descriptorObj);
} else {
onCacheDescriptorAvailable(null);
}
},
}
);
} else {
onCacheDescriptorAvailable(null);
}
},
};