gecko-dev/devtools/client/fronts/watcher.js

95 строки
3.2 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 { watcherSpec } = require("devtools/shared/specs/watcher");
const {
FrontClassWithSpec,
registerFront,
} = require("devtools/shared/protocol");
loader.lazyRequireGetter(
this,
"BrowsingContextTargetFront",
"devtools/client/fronts/targets/browsing-context",
true
);
class WatcherFront extends FrontClassWithSpec(watcherSpec) {
constructor(client, targetFront, parentFront) {
super(client, targetFront, parentFront);
this._onTargetAvailable = this._onTargetAvailable.bind(this);
this._onTargetDestroyed = this._onTargetDestroyed.bind(this);
// Convert form, which is just JSON object to Fronts for these two events
this.on("target-available-form", this._onTargetAvailable);
this.on("target-destroyed-form", this._onTargetDestroyed);
}
form(json) {
this.actorID = json.actor;
this.traits = json.traits;
}
_onTargetAvailable(form) {
const front = new BrowsingContextTargetFront(this.conn, null, this);
front.actorID = form.actor;
front.form(form);
this.manage(front);
this.emit("target-available", front);
}
_onTargetDestroyed(form) {
const front = this.getActorByID(form.actor);
this.emit("target-destroyed", front);
}
/**
* Retrieve the already existing BrowsingContextTargetFront for the parent
* BrowsingContext of the given BrowsingContext ID.
*/
async getParentBrowsingContextTarget(browsingContextID) {
const id = await this.getParentBrowsingContextID(browsingContextID);
if (!id) {
return null;
}
return this.getBrowsingContextTarget(id);
}
/**
* For a given BrowsingContext ID, return the already existing BrowsingContextTargetFront
*/
async getBrowsingContextTarget(id) {
// First scan the watcher children as the watcher manages all the targets
for (const front of this.poolChildren()) {
if (front.browsingContextID == id) {
return front;
}
}
// But the top level target will be created by the Descriptor.getTarget() method
// and so be hosted in the Descriptor's pool.
// The parent front of the WatcherActor happens to be the Descriptor Actor.
// This code could go away or be simplified if the Descriptor starts fetch all
// the targets, including the top level one via the Watcher. i.e. drop Descriptor.getTarget().
const topLevelTarget = await this.parentFront.getTarget();
if (topLevelTarget.browsingContextID == id) {
return topLevelTarget;
}
// If we could not find a browsing context target for the provided id, the
// browsing context might not be the topmost browsing context of a given
// process. For now we only create targets for the top browsing context of
// each process, so we recursively check the parent browsing context ids
// until we find a valid target.
const parentBrowsingContextID = await this.getParentBrowsingContextID(id);
if (parentBrowsingContextID && parentBrowsingContextID !== id) {
return this.getBrowsingContextTarget(parentBrowsingContextID);
}
return null;
}
}
registerFront(WatcherFront);