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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
"use strict";
const {
processDescriptorSpec,
} = require("resource://devtools/shared/specs/descriptors/process.js");
const {
WindowGlobalTargetFront,
} = require("resource://devtools/client/fronts/targets/window-global.js");
const {
ContentProcessTargetFront,
} = require("resource://devtools/client/fronts/targets/content-process.js");
const {
FrontClassWithSpec,
registerFront,
} = require("resource://devtools/shared/protocol.js");
const {
DescriptorMixin,
} = require("resource://devtools/client/fronts/descriptors/descriptor-mixin.js");
const DESCRIPTOR_TYPES = require("resource://devtools/client/fronts/descriptors/descriptor-types.js");
class ProcessDescriptorFront extends DescriptorMixin(
FrontClassWithSpec(processDescriptorSpec)
) {
constructor(client, targetFront, parentFront) {
super(client, targetFront, parentFront);
this._isParent = false;
this._processTargetFront = null;
this._targetFrontPromise = null;
}
descriptorType = DESCRIPTOR_TYPES.PROCESS;
form(json) {
this.id = json.id;
this._isParent = json.isParent;
this._isWindowlessParent = json.isWindowlessParent;
this.traits = json.traits || {};
}
async _createProcessTargetFront(form) {
let front = null;
// the request to getTarget may return a ContentProcessTargetActor or a
// ParentProcessTargetActor. In most cases getProcess(0) will return the
// main process target actor, which is a ParentProcessTargetActor, but
// not in xpcshell, which uses a ContentProcessTargetActor. So select
// the right front based on the actor ID.
if (form.actor.includes("parentProcessTarget")) {
// ParentProcessTargetActor doesn't have a specific front, instead it uses
// WindowGlobalTargetFront on the client side.
front = new WindowGlobalTargetFront(this._client, null, this);
} else {
front = new ContentProcessTargetFront(this._client, null, this);
}
// As these fronts aren't instantiated by protocol.js, we have to set their actor ID
// manually like that:
front.actorID = form.actor;
front.form(form);
// @backward-compat { version 84 } Older server don't send the processID in the form
if (!front.processID) {
front.processID = this.id;
}
this.manage(front);
return front;
}
/**
* This flag should be true for parent process descriptors of a regular
* browser instance, where you can expect the target to be associated with a
* window global.
*
* This will typically be true for the descriptor used by the Browser Toolbox
* or the Browser Console opened against a regular Firefox instance.
*
* On the contrary this will be false for parent process descriptors created
* for xpcshell debugging or for background task debugging.
*/
get isBrowserProcessDescriptor() {
return this._isParent && !this._isWindowlessParent;
}
get isParentProcessDescriptor() {
return this._isParent;
}
get isProcessDescriptor() {
return true;
}
getCachedTarget() {
return this._processTargetFront;
}
async getTarget() {
// Only return the cached Target if it is still alive.
if (this._processTargetFront && !this._processTargetFront.isDestroyed()) {
return this._processTargetFront;
}
// Otherwise, ensure that we don't try to spawn more than one Target by
// returning the pending promise
if (this._targetFrontPromise) {
return this._targetFrontPromise;
}
this._targetFrontPromise = (async () => {
let targetFront = null;
try {
const targetForm = await super.getTarget();
targetFront = await this._createProcessTargetFront(targetForm);
} catch (e) {
// This is likely to happen if we get a lot of events which drop previous
// processes.
console.log(
`Request to connect to ProcessDescriptor "${this.id}" failed: ${e}`
);
}
// Save the reference to the target only after the call to attach
// so that getTarget always returns the attached target in case of concurrent calls
this._processTargetFront = targetFront;
// clear the promise if we are finished so that we can re-connect if
// necessary
this._targetFrontPromise = null;
return targetFront;
})();
return this._targetFrontPromise;
}
destroy() {
if (this._processTargetFront) {
this._processTargetFront.destroy();
this._processTargetFront = null;
}
this._targetFrontPromise = null;
super.destroy();
}
}
exports.ProcessDescriptorFront = ProcessDescriptorFront;
registerFront(ProcessDescriptorFront);