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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";
/**
* Listening to worker updates requires watching various sources. This class provides
* a single addListener/removeListener API that will aggregate all possible worker update
* events.
*
* Only supports one listener at a time.
*/
class WorkersListener {
constructor(rootFront, { registrationsOnly = false } = {}) {
this.rootFront = rootFront;
this.registrationsOnly = registrationsOnly;
// bind handlers
this._onContentProcessTargetAvailable =
this._onContentProcessTargetAvailable.bind(this);
this._onServiceWorkerRegistrationAvailable =
this._onServiceWorkerRegistrationAvailable.bind(this);
this._onProcessDescriptorAvailable =
this._onProcessDescriptorAvailable.bind(this);
this._onContentProcessTargetDestroyed =
this._onContentProcessTargetDestroyed.bind(this);
this._onServiceWorkerRegistrationDestroyed =
this._onServiceWorkerRegistrationDestroyed.bind(this);
this._onProcessDescriptorDestroyed =
this._onProcessDescriptorDestroyed.bind(this);
// Array of contentProcessTarget fronts on which we will listen for worker events.
this._contentProcessFronts = [];
this._serviceWorkerRegistrationFronts = [];
this._processDescriptors = [];
this._listener = null;
}
addListener(listener) {
if (this._listener) {
throw new Error("WorkersListener addListener called twice.");
}
this._listener = listener;
if (!this.registrationsOnly) {
this.rootFront.on("workerListChanged", this._listener);
this.rootFront.watchFronts(
"processDescriptor",
this._onProcessDescriptorAvailable,
this._onProcessDescriptorDestroyed
);
this.rootFront.on("processListChanged", this._listener);
}
this.rootFront.watchFronts(
"serviceWorkerRegistration",
this._onServiceWorkerRegistrationAvailable,
this._onServiceWorkerRegistrationDestroyed
);
this.rootFront.on("serviceWorkerRegistrationListChanged", this._listener);
}
removeListener() {
if (!this._listener) {
return;
}
this.rootFront.off("workerListChanged", this._listener);
this.rootFront.off("serviceWorkerRegistrationListChanged", this._listener);
this.rootFront.off("processListChanged", this._listener);
for (const front of this._contentProcessFronts) {
front.off("workerListChanged", this._listener);
}
for (const front of this._serviceWorkerRegistrationFronts) {
front.off("push-subscription-modified", this._listener);
front.off("registration-changed", this._listener);
}
for (const processFront of this._processDescriptors) {
processFront.unwatchFronts(
"contentProcessTarget",
this._onContentProcessTargetAvailable
);
}
this.rootFront.unwatchFronts(
"processDescriptor",
this._onProcessDescriptorAvailable,
this._onProcessDescriptorDestroyed
);
this.rootFront.unwatchFronts(
"serviceWorkerRegistration",
this._onServiceWorkerRegistrationAvailable,
this._onServiceWorkerRegistrationDestroyed
);
this._contentProcessFronts = [];
this._serviceWorkerRegistrationFronts = [];
this._processDescriptors = [];
this._listener = null;
}
_onContentProcessTargetAvailable(front) {
this._contentProcessFronts.push(front);
front.on("workerListChanged", this._listener);
}
_onContentProcessTargetDestroyed(front) {
this._contentProcessFronts = this._contentProcessFronts.filter(
f => f !== front
);
}
_onServiceWorkerRegistrationAvailable(front) {
this._serviceWorkerRegistrationFronts.push(front);
front.on("push-subscription-modified", this._listener);
front.on("registration-changed", this._listener);
}
_onServiceWorkerRegistrationDestroyed(front) {
this._serviceWorkerRegistrationFronts =
this._serviceWorkerRegistrationFronts.filter(f => f !== front);
}
_onProcessDescriptorAvailable(processFront) {
this._processDescriptors.push(processFront);
processFront.watchFronts(
"contentProcessTarget",
this._onContentProcessTargetAvailable,
this._onContentProcessTargetDestroyed
);
}
_onProcessDescriptorDestroyed(processFront) {
this._processDescriptors = this._processDescriptors.filter(
f => f !== processFront
);
}
}
exports.WorkersListener = WorkersListener;