Files
tubestation/toolkit/components/messaging-system/lib/SharedDataMap.jsm

98 lines
2.1 KiB
JavaScript

/* 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 EXPORTED_SYMBOLS = ["SharedDataMap"];
const { Services } = ChromeUtils.import("resource://gre/modules/Services.jsm");
ChromeUtils.defineModuleGetter(
this,
"PromiseUtils",
"resource://gre/modules/PromiseUtils.jsm"
);
const IS_MAIN_PROCESS =
Services.appinfo.processType === Services.appinfo.PROCESS_TYPE_DEFAULT;
class SharedDataMap {
constructor(sharedDataKey) {
this._sharedDataKey = sharedDataKey;
this._isParent = IS_MAIN_PROCESS;
this._isReady = this.isParent;
this._readyDeferred = PromiseUtils.defer();
this._map = null;
if (this.isParent) {
this._map = new Map();
this._syncToChildren({ flush: true });
this._checkIfReady();
} else {
this._syncFromParent();
Services.cpmm.sharedData.addEventListener("change", this);
}
}
get sharedDataKey() {
return this._sharedDataKey;
}
get isParent() {
return this._isParent;
}
ready() {
return this._readyDeferred.promise;
}
get(key) {
return this._map.get(key);
}
set(key, value) {
if (!this.isParent) {
throw new Error(
"Setting values from within a content process is not allowed"
);
}
this._map.set(key, value);
this._syncToChildren();
}
has(key) {
return this._map.has(key);
}
toObject() {
return Object.fromEntries(this._map);
}
_syncToChildren({ flush = false } = {}) {
Services.ppmm.sharedData.set(this.sharedDataKey, this._map);
if (flush) {
Services.ppmm.sharedData.flush();
}
}
_syncFromParent() {
this._map = Services.cpmm.sharedData.get(this.sharedDataKey);
this._checkIfReady();
}
_checkIfReady() {
if (!this._isReady && this._map) {
this._isReady = true;
this._readyDeferred.resolve();
}
}
handleEvent(event) {
if (event.type === "change") {
if (event.changedKeys.includes(this.sharedDataKey)) {
this._syncFromParent();
}
}
}
}