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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
import { ContentProcessWatcherRegistry } from "resource://devtools/server/connectors/js-process-actor/ContentProcessWatcherRegistry.sys.mjs";
const lazy = {};
ChromeUtils.defineESModuleGetters(
lazy,
{
ProcessTargetWatcher:
SessionDataHelpers:
ServiceWorkerTargetWatcher:
WorkerTargetWatcher:
WindowGlobalTargetWatcher:
},
{ global: "contextual" }
);
// TargetActorRegistery has to be shared between all devtools instances
// and so is loaded into the shared global.
ChromeUtils.defineESModuleGetters(
lazy,
{
TargetActorRegistry:
},
{ global: "shared" }
);
export class DevToolsProcessChild extends JSProcessActorChild {
constructor() {
super();
// The EventEmitter interface is used for DevToolsTransport's packet-received event.
EventEmitter.decorate(this);
}
#watchers = {
// Keys are target types, which are defined in this CommonJS Module:
// We avoid loading it as this ESM should be lightweight and avoid spawning DevTools CommonJS Loader until
// whe know we have to instantiate a Target Actor.
frame: {
// Number of active watcher actors currently watching for the given target type
activeListener: 0,
// Instance of a target watcher class whose task is to observe new target instances
get watcher() {
return lazy.WindowGlobalTargetWatcher;
},
},
process: {
activeListener: 0,
get watcher() {
return lazy.ProcessTargetWatcher;
},
},
worker: {
activeListener: 0,
get watcher() {
return lazy.WorkerTargetWatcher;
},
},
service_worker: {
activeListener: 0,
get watcher() {
return lazy.ServiceWorkerTargetWatcher;
},
},
};
#initialized = false;
/**
* Called when this JSProcess Actor instantiate either when we start observing for first target types,
* or when the process just started.
*/
instantiate() {
if (this.#initialized) {
return;
}
this.#initialized = true;
// Create and watch for future target actors for each watcher currently watching some target types
for (const watcherDataObject of ContentProcessWatcherRegistry.getAllWatchersDataObjects()) {
this.#watchInitialTargetsForWatcher(watcherDataObject);
}
}
/**
* Instantiate and watch future target actors based on the already watched targets.
*
* @param Object watcherDataObject
* See ContentProcessWatcherRegistry.
*/
#watchInitialTargetsForWatcher(watcherDataObject) {
const { sessionData, sessionContext } = watcherDataObject;
// About WebExtension, see note in addOrSetSessionDataEntry.
// Their target actor aren't created by this class, but session data is still managed by it
// and we need to pass the initial session data coming to already instantiated target actor.
if (sessionContext.type == "webextension") {
const { watcherActorID } = watcherDataObject;
const connectionPrefix = watcherActorID.replace(/watcher\d+$/, "");
const targetActors = lazy.TargetActorRegistry.getTargetActors(
sessionContext,
connectionPrefix
);
if (targetActors.length) {
// Pass initialization data to the target actor
for (const type in sessionData) {
// `sessionData` will also contain `browserId` as well as entries with empty arrays,
// which shouldn't be processed.
const entries = sessionData[type];
if (!Array.isArray(entries) || !entries.length) {
continue;
}
targetActors[0].addOrSetSessionDataEntry(type, entries, false, "set");
}
}
}
// Ignore the call if the watched targets property isn't populated yet.
// This typically happens when instantiating the JS Process Actor on toolbox opening,
// where the actor is spawn early and a watchTarget message comes later with the `targets` array set.
if (!sessionData.targets) {
return;
}
for (const targetType of sessionData.targets) {
this.#watchNewTargetTypeForWatcher(watcherDataObject, targetType, true);
}
}
/**
* Instantiate and watch future target actors based on the already watched targets.
*
* @param Object watcherDataObject
* See ContentProcessWatcherRegistry.
* @param String targetType
* New typeof target to start watching.
* @param Boolean isProcessActorStartup
* True when we are watching for targets during this JS Process actor instantiation.
* It shouldn't be the case on toolbox opening, but only when a new process starts.
* On toolbox opening, the Actor will receive an explicit watchTargets query.
*/
#watchNewTargetTypeForWatcher(
watcherDataObject,
targetType,
isProcessActorStartup
) {
const { watchingTargetTypes } = watcherDataObject;
// Ensure creating and watching only once per target type and watcher actor.
if (watchingTargetTypes.includes(targetType)) {
return;
}
watchingTargetTypes.push(targetType);
// Update sessionData as watched target types are a Session Data
// used later for example by worker target watcher
lazy.SessionDataHelpers.addOrSetSessionDataEntry(
watcherDataObject.sessionData,
"targets",
[targetType],
"add"
);
this.#watchers[targetType].activeListener++;
// Start listening for platform events when we are observing this type for the first time
if (this.#watchers[targetType].activeListener === 1) {
this.#watchers[targetType].watcher.watch();
}
// And instantiate targets for the already existing instances
this.#watchers[targetType].watcher.createTargetsForWatcher(
watcherDataObject,
isProcessActorStartup
);
}
/**
* Stop watching for all target types and destroy all existing targets actor
* related to a given watcher actor.
*
* @param {Object} watcherDataObject
* @param {String} targetType
* @param {Object} options
*/
#unwatchTargetsForWatcher(watcherDataObject, targetType, options) {
const { watchingTargetTypes } = watcherDataObject;
const targetTypeIndex = watchingTargetTypes.indexOf(targetType);
// Ignore targetTypes which were not observed
if (targetTypeIndex === -1) {
return;
}
// Update to the new list of currently watched target types
watchingTargetTypes.splice(targetTypeIndex, 1);
// Update sessionData as watched target types are a Session Data
// used later for example by worker target watcher
lazy.SessionDataHelpers.removeSessionDataEntry(
watcherDataObject.sessionData,
"targets",
[targetType]
);
this.#watchers[targetType].activeListener--;
// Stop observing for platform events
if (this.#watchers[targetType].activeListener === 0) {
this.#watchers[targetType].watcher.unwatch();
}
// Destroy all targets which are still instantiated for this type
this.#watchers[targetType].watcher.destroyTargetsForWatcher(
watcherDataObject,
options
);
// Unregister the watcher if we stopped watching for all target types
if (!watchingTargetTypes.length) {
ContentProcessWatcherRegistry.remove(watcherDataObject);
}
// If we removed the last watcher, clean the internal state of this class.
if (ContentProcessWatcherRegistry.isEmpty()) {
this.didDestroy(options);
}
}
/**
* Cleanup everything around a given watcher actor
*
* @param {Object} watcherDataObject
*/
#destroyWatcher(watcherDataObject) {
const { watchingTargetTypes } = watcherDataObject;
// Clone the array as it will be modified during the loop execution
for (const targetType of [...watchingTargetTypes]) {
this.#unwatchTargetsForWatcher(watcherDataObject, targetType);
}
}
/**
* Used by DevTools Transport to send packets to the content process.
*
* @param {JSON} packet
* @param {String} prefix
*/
sendPacket(packet, prefix) {
this.sendAsyncMessage("DevToolsProcessChild:packet", { packet, prefix });
}
/**
* JsWindowActor API
*/
async sendQuery(msg, args) {
try {
const res = await super.sendQuery(msg, args);
return res;
} catch (e) {
console.error("Failed to sendQuery in DevToolsProcessChild", msg);
console.error(e.toString());
throw e;
}
}
/**
* Called by the JSProcessActor API when the process process sent us a message.
*/
receiveMessage(message) {
switch (message.name) {
case "DevToolsProcessParent:watchTargets": {
const { watcherActorID, targetType } = message.data;
const watcherDataObject =
ContentProcessWatcherRegistry.getWatcherDataObject(watcherActorID);
return this.#watchNewTargetTypeForWatcher(
watcherDataObject,
targetType
);
}
case "DevToolsProcessParent:unwatchTargets": {
const { watcherActorID, targetType, options } = message.data;
const watcherDataObject =
ContentProcessWatcherRegistry.getWatcherDataObject(watcherActorID);
return this.#unwatchTargetsForWatcher(
watcherDataObject,
targetType,
options
);
}
case "DevToolsProcessParent:addOrSetSessionDataEntry": {
const { watcherActorID, type, entries, updateType } = message.data;
return this.#addOrSetSessionDataEntry(
watcherActorID,
type,
entries,
updateType
);
}
case "DevToolsProcessParent:removeSessionDataEntry": {
const { watcherActorID, type, entries } = message.data;
return this.#removeSessionDataEntry(watcherActorID, type, entries);
}
case "DevToolsProcessParent:destroyWatcher": {
const { watcherActorID } = message.data;
const watcherDataObject =
ContentProcessWatcherRegistry.getWatcherDataObject(
watcherActorID,
true
);
// The watcher may already be destroyed if the client unwatched for all target types.
if (watcherDataObject) {
return this.#destroyWatcher(watcherDataObject);
}
return null;
}
case "DevToolsProcessParent:packet":
return this.emit("packet-received", message);
default:
throw new Error(
"Unsupported message in DevToolsProcessParent: " + message.name
);
}
}
/**
* The parent process requested that some session data have been added or set.
*
* @param {String} watcherActorID
* The Watcher Actor ID requesting to add new session data
* @param {String} type
* The type of data to be added
* @param {Array<Object>} entries
* The values to be added to this type of data
* @param {String} updateType
* "add" will only add the new entries in the existing data set.
* "set" will update the data set with the new entries.
*/
async #addOrSetSessionDataEntry(watcherActorID, type, entries, updateType) {
const watcherDataObject =
ContentProcessWatcherRegistry.getWatcherDataObject(watcherActorID);
// Maintain the copy of `sessionData` so that it is up-to-date when
// a new worker target needs to be instantiated
const { sessionData } = watcherDataObject;
lazy.SessionDataHelpers.addOrSetSessionDataEntry(
sessionData,
type,
entries,
updateType
);
// This type is really specific to Service Workers and doesn't need to be transferred to any target.
// We only need to instantiate and destroy the target actors based on this new host.
const { watchingTargetTypes } = watcherDataObject;
if (type == "browser-element-host") {
if (watchingTargetTypes.includes("service_worker")) {
this.#watchers.service_worker.watcher.updateBrowserElementHost(
watcherDataObject
);
}
return;
}
const promises = [];
for (const targetActor of watcherDataObject.actors) {
promises.push(
targetActor.addOrSetSessionDataEntry(type, entries, false, updateType)
);
}
// Very special codepath for Web Extensions.
// Their WebExtension Target Actor is still created manually by WebExtensionDescritpor.getTarget,
// via a message manager. That, instead of being instantiated via the WatcherActor.watchTargets and this JSProcess actor.
// The Watcher Actor will still instantiate a JS Actor for the WebExt DOM Content Process
// and send the addOrSetSessionDataEntry query. But as the target actor isn't managed by the JS Actor,
// we have to manually retrieve it via the TargetActorRegistry.
if (sessionData.sessionContext.type == "webextension") {
const connectionPrefix = watcherActorID.replace(/watcher\d+$/, "");
const targetActors = lazy.TargetActorRegistry.getTargetActors(
sessionData.sessionContext,
connectionPrefix
);
// We will have a single match only in the DOM Process where the add-on runs
if (targetActors.length) {
promises.push(
targetActors[0].addOrSetSessionDataEntry(
type,
entries,
false,
updateType
)
);
}
}
await Promise.all(promises);
if (watchingTargetTypes.includes("worker")) {
await this.#watchers.worker.watcher.addOrSetSessionDataEntry(
watcherDataObject,
type,
entries,
updateType
);
}
if (watchingTargetTypes.includes("service_worker")) {
await this.#watchers.service_worker.watcher.addOrSetSessionDataEntry(
watcherDataObject,
type,
entries,
updateType
);
}
}
/**
* The parent process requested that some session data have been removed.
*
* @param {String} watcherActorID
* The Watcher Actor ID requesting to remove session data
* @param {String}} type
* The type of data to be removed
* @param {Array<Object>} entries
* The values to be removed to this type of data
*/
#removeSessionDataEntry(watcherActorID, type, entries) {
const watcherDataObject =
ContentProcessWatcherRegistry.getWatcherDataObject(watcherActorID, true);
// When we unwatch resources after targets during the devtools shutdown,
// the watcher will be removed on last target type unwatch.
if (!watcherDataObject) {
return;
}
// Maintain the copy of `sessionData` so that it is up-to-date when
// a new worker target needs to be instantiated
lazy.SessionDataHelpers.removeSessionDataEntry(
watcherDataObject.sessionData,
type,
entries
);
for (const targetActor of watcherDataObject.actors) {
targetActor.removeSessionDataEntry(type, entries);
}
}
/**
* Observer service notification handler.
*
* @param {DOMWindow|Document} subject
* A window for *-document-global-created
* A document for *-page-{shown|hide}
* @param {String} topic
*/
observe = (subject, topic) => {
if (topic === "init-devtools-content-process-actor") {
// This is triggered by the process actor registration and some code in process-helper.js
// which defines a unique topic to be observed
this.instantiate();
}
};
/**
* Called by JS Process Actor API when the current process is destroyed,
* but also within this class when the last watcher stopped watching for targets.
*/
didDestroy() {
// Stop watching for all target types
for (const entry of Object.values(this.#watchers)) {
if (entry.activeListener > 0) {
entry.watcher.unwatch();
entry.activeListener = 0;
}
}
ContentProcessWatcherRegistry.clear();
}
}
export class BrowserToolboxDevToolsProcessChild extends DevToolsProcessChild {}