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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, {
isBrowsingContextCompatible:
MessageHandlerRegistry:
WindowGlobalMessageHandler:
});
/**
* Map from MessageHandlerRegistry to MessageHandlerFrameChild actor. This will
* allow a WindowGlobalMessageHandler to find the JSWindowActorChild instance to
* use to send commands.
*/
const registryToActor = new WeakMap();
/**
* Retrieve the MessageHandlerFrameChild which is linked to the provided
* WindowGlobalMessageHandler instance.
*
* @param {WindowGlobalMessageHandler} messageHandler
* The WindowGlobalMessageHandler for which to get the JSWindowActor.
* @returns {MessageHandlerFrameChild}
* The corresponding MessageHandlerFrameChild instance.
*/
export function getMessageHandlerFrameChildActor(messageHandler) {
return registryToActor.get(messageHandler.registry);
}
/**
* Child actor for the MessageHandlerFrame JSWindowActor. The
* MessageHandlerFrame actor is used by RootTransport to communicate between
* ROOT MessageHandlers and WINDOW_GLOBAL MessageHandlers.
*/
export class MessageHandlerFrameChild extends JSWindowActorChild {
actorCreated() {
this.type = lazy.WindowGlobalMessageHandler.type;
this.context = this.manager.browsingContext;
this._registry = new lazy.MessageHandlerRegistry(this.type, this.context);
registryToActor.set(this._registry, this);
this._onRegistryEvent = this._onRegistryEvent.bind(this);
// MessageHandlerFrameChild is responsible for forwarding events from
// WindowGlobalMessageHandler to the parent process.
// Such events are re-emitted on the MessageHandlerRegistry to avoid
// setting up listeners on individual MessageHandler instances.
this._registry.on("message-handler-registry-event", this._onRegistryEvent);
}
handleEvent({ persisted, type }) {
if (type == "DOMWindowCreated" || (type == "pageshow" && persisted)) {
// When the window is created or is retrieved from BFCache, instantiate
// a MessageHandler for all sessions which might need it.
if (lazy.isBrowsingContextCompatible(this.manager.browsingContext)) {
this._registry.createAllMessageHandlers();
}
} else if (type == "pagehide" && persisted) {
// When the page is moved to BFCache, all the currently created message
// handlers should be destroyed.
this._registry.destroy();
}
}
async receiveMessage(message) {
if (message.name === "MessageHandlerFrameParent:sendCommand") {
const { sessionId, command } = message.data;
const messageHandler =
this._registry.getOrCreateMessageHandler(sessionId);
try {
return await messageHandler.handleCommand(command);
} catch (e) {
if (e?.isRemoteError) {
return {
error: e.toJSON(),
isMessageHandlerError: e.isMessageHandlerError,
};
}
throw e;
}
}
return null;
}
sendCommand(command, sessionId) {
return this.sendQuery("MessageHandlerFrameChild:sendCommand", {
command,
sessionId,
});
}
_onRegistryEvent(eventName, wrappedEvent) {
this.sendAsyncMessage(
"MessageHandlerFrameChild:messageHandlerEvent",
wrappedEvent
);
}
didDestroy() {
this._registry.off("message-handler-registry-event", this._onRegistryEvent);
this._registry.destroy();
}
}