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
import { MessageHandler } from "chrome://remote/content/shared/messagehandler/MessageHandler.sys.mjs";
const lazy = {};
ChromeUtils.defineESModuleGetters(lazy, {
RootTransport:
SessionData:
SessionDataMethod:
WindowGlobalMessageHandler:
});
/**
* A RootMessageHandler is the root node of a MessageHandler network. It lives
* in the parent process. It can forward commands to MessageHandlers in other
* layers (at the moment WindowGlobalMessageHandlers in content processes).
*/
export class RootMessageHandler extends MessageHandler {
#navigationManager;
#realms;
#rootTransport;
#sessionData;
/**
* Returns the RootMessageHandler module path.
*
* @returns {string}
*/
static get modulePath() {
return "root";
}
/**
* Returns the RootMessageHandler type.
*
* @returns {string}
*/
static get type() {
return "ROOT";
}
/**
* The ROOT MessageHandler is unique for a given MessageHandler network
* (ie for a given sessionId). Reuse the type as context id here.
*/
static getIdFromContext() {
return RootMessageHandler.type;
}
/**
* Create a new RootMessageHandler instance.
*
* @param {string} sessionId
* ID of the session the handler is used for.
*/
constructor(sessionId) {
super(sessionId, null);
this.#rootTransport = new lazy.RootTransport(this);
this.#sessionData = new lazy.SessionData(this);
this.#navigationManager = new lazy.NavigationManager();
this.#navigationManager.startMonitoring();
// Map with inner window ids as keys, and sets of realm ids, assosiated with
// this window as values.
this.#realms = new Map();
// In the general case, we don't get notified that realms got destroyed,
// because there is no communication between content and parent process at this moment,
// so we have to listen to the this notification to clean up the internal
// map and trigger the events.
Services.obs.addObserver(this, "window-global-destroyed");
}
get navigationManager() {
return this.#navigationManager;
}
get realms() {
return this.#realms;
}
get sessionData() {
return this.#sessionData;
}
destroy() {
this.#sessionData.destroy();
this.#navigationManager.destroy();
Services.obs.removeObserver(this, "window-global-destroyed");
this.#realms = null;
super.destroy();
}
/**
* Add new session data items of a given module, category and
* contextDescriptor.
*
* Forwards the call to the SessionData instance owned by this
* RootMessageHandler and propagates the information via a command to existing
* MessageHandlers.
*/
addSessionDataItem(sessionData = {}) {
sessionData.method = lazy.SessionDataMethod.Add;
return this.updateSessionData([sessionData]);
}
emitEvent(name, eventPayload, contextInfo) {
// Intercept realm created and destroyed events to update internal map.
if (name === "realm-created") {
this.#onRealmCreated(eventPayload);
}
// We receive this events in the case of moving the page to BFCache.
if (name === "windowglobal-pagehide") {
this.#cleanUpRealmsForWindow(
eventPayload.innerWindowId,
eventPayload.context
);
}
super.emitEvent(name, eventPayload, contextInfo);
}
/**
* Emit a public protocol event. This event will be sent over to the client.
*
* @param {string} name
* Name of the event. Protocol level events should be of the
* form [module name].[event name].
* @param {object} data
* The event's data.
*/
emitProtocolEvent(name, data) {
this.emit("message-handler-protocol-event", {
name,
data,
sessionId: this.sessionId,
});
}
/**
* Forward the provided command to WINDOW_GLOBAL MessageHandlers via the
* RootTransport.
*
* @param {Command} command
* The command to forward. See type definition in MessageHandler.js
* @returns {Promise}
* Returns a promise that resolves with the result of the command.
*/
forwardCommand(command) {
switch (command.destination.type) {
case lazy.WindowGlobalMessageHandler.type:
return this.#rootTransport.forwardCommand(command);
default:
throw new Error(
`Cannot forward command to "${command.destination.type}" from "${this.constructor.type}".`
);
}
}
matchesContext() {
return true;
}
observe(subject, topic) {
if (topic !== "window-global-destroyed") {
return;
}
this.#cleanUpRealmsForWindow(
subject.innerWindowId,
subject.browsingContext
);
}
/**
* Remove session data items of a given module, category and
* contextDescriptor.
*
* Forwards the call to the SessionData instance owned by this
* RootMessageHandler and propagates the information via a command to existing
* MessageHandlers.
*/
removeSessionDataItem(sessionData = {}) {
sessionData.method = lazy.SessionDataMethod.Remove;
return this.updateSessionData([sessionData]);
}
/**
* Update session data items of a given module, category and
* contextDescriptor.
*
* Forwards the call to the SessionData instance owned by this
* RootMessageHandler.
*/
async updateSessionData(sessionData = []) {
await this.#sessionData.updateSessionData(sessionData);
}
#cleanUpRealmsForWindow(innerWindowId, context) {
const realms = this.#realms.get(innerWindowId);
if (!realms) {
return;
}
realms.forEach(realm => {
this.#realms.get(innerWindowId).delete(realm);
this.emitEvent("realm-destroyed", {
context,
realm,
});
});
this.#realms.delete(innerWindowId);
}
#onRealmCreated = data => {
const { innerWindowId, realmInfo } = data;
if (!this.#realms.has(innerWindowId)) {
this.#realms.set(innerWindowId, new Set());
}
this.#realms.get(innerWindowId).add(realmInfo.realm);
};
}