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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 file,
const lazy = {};
ChromeUtils.defineESModuleGetters(lazy, {
AsyncShutdown: "resource://gre/modules/AsyncShutdown.sys.mjs",
});
ChromeUtils.defineLazyGetter(lazy, "console", () => {
return console.createInstance({
prefix: "NotificationDB",
maxLogLevelPref: "dom.webnotifications.loglevel",
});
});
const NOTIFICATION_STORE_DIR = PathUtils.profileDir;
const NOTIFICATION_STORE_PATH = PathUtils.join(
NOTIFICATION_STORE_DIR,
"notificationstore.json"
);
export class NotificationDB {
// Ensure we won't call init() while xpcom-shutdown is performed
#shutdownInProgress = false;
// A promise that resolves once the ongoing task queue has been drained.
// The value will be reset when the queue starts again.
#queueDrainedPromise = null;
#queueDrainedPromiseResolve = null;
#byTag = Object.create(null);
#notifications = Object.create(null);
#loaded = false;
#tasks = [];
#runningTask = null;
storageQualifier() {
return "Notification";
}
prefixStorageQualifier(message) {
return `${this.storageQualifier()}:${message}`;
}
formatMessageType(message) {
return this.prefixStorageQualifier(message);
}
supportedMessageTypes() {
return [
this.formatMessageType("Save"),
this.formatMessageType("Delete"),
this.formatMessageType("GetAll"),
];
}
constructor() {
if (this.#shutdownInProgress) {
return;
}
this.#notifications = Object.create(null);
this.#byTag = Object.create(null);
this.#loaded = false;
this.#tasks = []; // read/write operation queue
this.#runningTask = null;
Services.obs.addObserver(this, "xpcom-shutdown");
this.registerListeners();
// This assumes that nothing will queue a new task at profile-change-teardown phase,
// potentially replacing the #queueDrainedPromise if there was no existing task run.
lazy.AsyncShutdown.profileChangeTeardown.addBlocker(
"NotificationDB: Need to make sure that all notification messages are processed",
() => this.#queueDrainedPromise
);
}
registerListeners() {
for (let message of this.supportedMessageTypes()) {
Services.ppmm.addMessageListener(message, this);
}
}
unregisterListeners() {
for (let message of this.supportedMessageTypes()) {
Services.ppmm.removeMessageListener(message, this);
}
}
observe(aSubject, aTopic) {
lazy.console.debug(`Topic: ${aTopic}`);
if (aTopic == "xpcom-shutdown") {
this.#shutdownInProgress = true;
Services.obs.removeObserver(this, "xpcom-shutdown");
this.unregisterListeners();
}
}
filterNonAppNotifications(notifications) {
let result = Object.create(null);
for (let origin in notifications) {
result[origin] = Object.create(null);
let persistentNotificationCount = 0;
for (let id in notifications[origin]) {
if (notifications[origin][id].serviceWorkerRegistrationScope) {
persistentNotificationCount++;
result[origin][id] = notifications[origin][id];
}
}
if (persistentNotificationCount == 0) {
lazy.console.debug(
`Origin ${origin} is not linked to an app manifest, deleting.`
);
delete result[origin];
}
}
return result;
}
// Attempt to read notification file, if it's not there we will create it.
load() {
var promise = IOUtils.readUTF8(NOTIFICATION_STORE_PATH);
return promise.then(
data => {
if (data.length) {
// Preprocessing phase intends to cleanly separate any migration-related
// tasks.
this.#notifications = this.filterNonAppNotifications(
JSON.parse(data)
);
}
// populate the list of notifications by tag
if (this.#notifications) {
for (var origin in this.#notifications) {
this.#byTag[origin] = Object.create(null);
for (var id in this.#notifications[origin]) {
var curNotification = this.#notifications[origin][id];
if (curNotification.tag) {
this.#byTag[origin][curNotification.tag] = curNotification;
}
}
}
}
this.#loaded = true;
},
// If read failed, we assume we have no notifications to load.
() => {
this.#loaded = true;
return this.createStore();
}
);
}
// Creates the notification directory.
createStore() {
var promise = IOUtils.makeDirectory(NOTIFICATION_STORE_DIR, {
ignoreExisting: true,
});
return promise.then(this.createFile.bind(this));
}
// Creates the notification file once the directory is created.
createFile() {
return IOUtils.writeUTF8(NOTIFICATION_STORE_PATH, "", {
tmpPath: NOTIFICATION_STORE_PATH + ".tmp",
});
}
// Save current notifications to the file.
save() {
var data = JSON.stringify(this.#notifications);
return IOUtils.writeUTF8(NOTIFICATION_STORE_PATH, data, {
tmpPath: NOTIFICATION_STORE_PATH + ".tmp",
});
}
// Helper function: promise will be resolved once file exists and/or is loaded.
#ensureLoaded() {
if (!this.#loaded) {
return this.load();
}
return Promise.resolve();
}
receiveMessage(message) {
lazy.console.debug(`Received message: ${message.name}`);
// sendAsyncMessage can fail if the child process exits during a
// notification storage operation, so always wrap it in a try/catch.
function returnMessage(name, data) {
try {
message.target.sendAsyncMessage(name, data);
} catch (e) {
lazy.console.debug(`Return message failed, ${name}`);
}
}
switch (message.name) {
case this.formatMessageType("GetAll"):
this.queueTask("getall", message.data)
.then(notifications => {
returnMessage(this.formatMessageType("GetAll:Return:OK"), {
requestID: message.data.requestID,
origin: message.data.origin,
notifications,
});
})
.catch(error => {
returnMessage(this.formatMessageType("GetAll:Return:KO"), {
requestID: message.data.requestID,
origin: message.data.origin,
errorMsg: error,
});
});
break;
case this.formatMessageType("Save"):
this.queueTask("save", message.data)
.then(() => {
returnMessage(this.formatMessageType("Save:Return:OK"), {
requestID: message.data.requestID,
});
})
.catch(error => {
returnMessage(this.formatMessageType("Save:Return:KO"), {
requestID: message.data.requestID,
errorMsg: error,
});
});
break;
case this.formatMessageType("Delete"):
this.queueTask("delete", message.data)
.then(() => {
returnMessage(this.formatMessageType("Delete:Return:OK"), {
requestID: message.data.requestID,
});
})
.catch(error => {
returnMessage(this.formatMessageType("Delete:Return:KO"), {
requestID: message.data.requestID,
errorMsg: error,
});
});
break;
default:
lazy.console.debug(`Invalid message name ${message.name}`);
}
}
// We need to make sure any read/write operations are atomic,
// so use a queue to run each operation sequentially.
queueTask(operation, data) {
lazy.console.debug(`Queueing task: ${operation}`);
var defer = {};
this.#tasks.push({
operation,
data,
defer,
});
var promise = new Promise((resolve, reject) => {
defer.resolve = resolve;
defer.reject = reject;
});
// Only run immediately if we aren't currently running another task.
if (!this.#runningTask) {
lazy.console.debug("Task queue was not running, starting now...");
this.runNextTask();
this.#queueDrainedPromise = new Promise(resolve => {
this.#queueDrainedPromiseResolve = resolve;
});
}
return promise;
}
runNextTask() {
if (this.#tasks.length === 0) {
lazy.console.debug("No more tasks to run, queue depleted");
this.#runningTask = null;
if (this.#queueDrainedPromiseResolve) {
this.#queueDrainedPromiseResolve();
} else {
lazy.console.debug(
"#queueDrainedPromiseResolve was null somehow, no promise to resolve"
);
}
return;
}
this.#runningTask = this.#tasks.shift();
// Always make sure we are loaded before performing any read/write tasks.
this.#ensureLoaded()
.then(() => {
var task = this.#runningTask;
switch (task.operation) {
case "getall":
return this.taskGetAll(task.data);
case "save":
return this.taskSave(task.data);
case "delete":
return this.taskDelete(task.data);
default:
return Promise.reject(
new Error(`Found a task with unknown operation ${task.operation}`)
);
}
})
.then(payload => {
lazy.console.debug(`Finishing task: ${this.#runningTask.operation}`);
this.#runningTask.defer.resolve(payload);
})
.catch(err => {
lazy.console.debug(
`Error while running ${this.#runningTask.operation}: ${err}`
);
this.#runningTask.defer.reject(err);
})
.then(() => {
this.runNextTask();
});
}
taskGetAll(data) {
lazy.console.debug("Task, getting all");
var origin = data.origin;
var notifications = [];
// Grab only the notifications for specified origin.
if (this.#notifications[origin]) {
if (data.tag) {
let n;
if ((n = this.#byTag[origin][data.tag])) {
notifications.push(n);
}
} else {
for (var i in this.#notifications[origin]) {
notifications.push(this.#notifications[origin][i]);
}
}
}
return Promise.resolve(notifications);
}
taskSave(data) {
lazy.console.debug("Task, saving");
var origin = data.origin;
var notification = data.notification;
if (!this.#notifications[origin]) {
this.#notifications[origin] = Object.create(null);
this.#byTag[origin] = Object.create(null);
}
// We might have existing notification with this tag,
// if so we need to remove it before saving the new one.
if (notification.tag) {
var oldNotification = this.#byTag[origin][notification.tag];
if (oldNotification) {
delete this.#notifications[origin][oldNotification.id];
}
this.#byTag[origin][notification.tag] = notification;
}
this.#notifications[origin][notification.id] = notification;
return this.save();
}
taskDelete(data) {
lazy.console.debug("Task, deleting");
var origin = data.origin;
var id = data.id;
if (!this.#notifications[origin]) {
lazy.console.debug(`No notifications found for origin: ${origin}`);
return Promise.resolve();
}
// Make sure we can find the notification to delete.
var oldNotification = this.#notifications[origin][id];
if (!oldNotification) {
lazy.console.debug(`No notification found with id: ${id}`);
return Promise.resolve();
}
if (oldNotification.tag) {
delete this.#byTag[origin][oldNotification.tag];
}
delete this.#notifications[origin][id];
return this.save();
}
}
new NotificationDB();