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/* 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, {
});
const IS_MAIN_PROCESS =
Services.appinfo.processType === Services.appinfo.PROCESS_TYPE_DEFAULT;
export class SharedDataMap extends EventEmitter {
constructor(sharedDataKey, options = { isParent: IS_MAIN_PROCESS }) {
super();
this._sharedDataKey = sharedDataKey;
this._isParent = options.isParent;
this._isReady = false;
this._readyDeferred = Promise.withResolvers();
this._data = null;
if (this.isParent) {
// Lazy-load JSON file that backs Storage instances.
ChromeUtils.defineLazyGetter(this, "_store", () => {
let path = options.path;
let store = null;
if (!path) {
try {
const profileDir = Services.dirsvc.get("ProfD", Ci.nsIFile).path;
path = PathUtils.join(profileDir, `${sharedDataKey}.json`);
} catch (e) {
console.error(e);
}
}
try {
store = new lazy.JSONFile({ path });
} catch (e) {
console.error(e);
}
return store;
});
} else {
this._syncFromParent();
Services.cpmm.sharedData.addEventListener("change", this);
}
}
async init() {
if (!this._isReady && this.isParent) {
try {
await this._store.load();
this._data = this._store.data;
this._syncToChildren({ flush: true });
this._checkIfReady();
} catch (e) {
console.error(e);
}
}
}
get sharedDataKey() {
return this._sharedDataKey;
}
get isParent() {
return this._isParent;
}
ready() {
return this._readyDeferred.promise;
}
get(key) {
if (!this._data) {
return null;
}
let entry = this._data[key];
return entry;
}
set(key, value) {
if (!this.isParent) {
throw new Error(
"Setting values from within a content process is not allowed"
);
}
this._store.data[key] = value;
this._store.saveSoon();
this._syncToChildren();
this._notifyUpdate();
}
/**
* Replace the stored data with an updated filtered dataset for cleanup
* purposes. We don't notify of update because we're only filtering out
* old unused entries.
*
* @param {string[]} keysToRemove - list of keys to remove from the persistent store
*/
_removeEntriesByKeys(keysToRemove) {
if (!keysToRemove.length) {
return;
}
for (let key of keysToRemove) {
try {
delete this._store.data[key];
} catch (e) {
// It's ok if this fails
}
}
this._store.saveSoon();
}
// Only used in tests
_deleteForTests(key) {
if (!this.isParent) {
throw new Error(
"Setting values from within a content process is not allowed"
);
}
if (this.has(key)) {
delete this._store.data[key];
this._store.saveSoon();
this._syncToChildren();
this._notifyUpdate();
}
}
has(key) {
return Boolean(this.get(key));
}
/**
* Notify store listeners of updates
* Called both from Main and Content process
*/
_notifyUpdate(process = "parent") {
for (let key of Object.keys(this._data || {})) {
this.emit(`${process}-store-update:${key}`, this._data[key]);
}
}
_syncToChildren({ flush = false } = {}) {
Services.ppmm.sharedData.set(this.sharedDataKey, {
...this._data,
});
if (flush) {
Services.ppmm.sharedData.flush();
}
}
_syncFromParent() {
this._data = Services.cpmm.sharedData.get(this.sharedDataKey);
this._checkIfReady();
this._notifyUpdate("child");
}
_checkIfReady() {
if (!this._isReady && this._data) {
this._isReady = true;
this._readyDeferred.resolve();
}
}
handleEvent(event) {
if (event.type === "change") {
if (event.changedKeys.includes(this.sharedDataKey)) {
this._syncFromParent();
}
}
}
}