tenfourfox/addon-sdk/source/lib/sdk/deprecated/sync-worker.js
Cameron Kaiser c9b2922b70 hello FPR
2017-04-19 00:56:45 -07:00

289 lines
8.7 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/. */
/**
*
* `deprecated/sync-worker` was previously `content/worker`, that was
* incompatible with e10s. we are in the process of switching to the new
* asynchronous `Worker`, which behaves slightly differently in some edge
* cases, so we are keeping this one around for a short period.
* try to switch to the new one as soon as possible..
*
*/
"use strict";
module.metadata = {
"stability": "unstable"
};
const { Class } = require('../core/heritage');
const { EventTarget } = require('../event/target');
const { on, off, emit, setListeners } = require('../event/core');
const {
attach, detach, destroy
} = require('../content/utils');
const { method } = require('../lang/functional');
const { Ci, Cu, Cc } = require('chrome');
const unload = require('../system/unload');
const events = require('../system/events');
const { getInnerId } = require("../window/utils");
const { WorkerSandbox } = require('../content/sandbox');
const { isPrivate } = require('../private-browsing/utils');
// A weak map of workers to hold private attributes that
// should not be exposed
const workers = new WeakMap();
var modelFor = (worker) => workers.get(worker);
const ERR_DESTROYED =
"Couldn't find the worker to receive this message. " +
"The script may not be initialized yet, or may already have been unloaded.";
const ERR_FROZEN = "The page is currently hidden and can no longer be used " +
"until it is visible again.";
/**
* Message-passing facility for communication between code running
* in the content and add-on process.
* @see https://developer.mozilla.org/en-US/Add-ons/SDK/Low-Level_APIs/content_worker
*/
const Worker = Class({
implements: [EventTarget],
initialize: function WorkerConstructor (options) {
// Save model in weak map to not expose properties
let model = createModel();
workers.set(this, model);
options = options || {};
if ('contentScriptFile' in options)
this.contentScriptFile = options.contentScriptFile;
if ('contentScriptOptions' in options)
this.contentScriptOptions = options.contentScriptOptions;
if ('contentScript' in options)
this.contentScript = options.contentScript;
if ('injectInDocument' in options)
this.injectInDocument = !!options.injectInDocument;
setListeners(this, options);
unload.ensure(this, "destroy");
// Ensure that worker.port is initialized for contentWorker to be able
// to send events during worker initialization.
this.port = createPort(this);
model.documentUnload = documentUnload.bind(this);
model.pageShow = pageShow.bind(this);
model.pageHide = pageHide.bind(this);
if ('window' in options)
attach(this, options.window);
},
/**
* Sends a message to the worker's global scope. Method takes single
* argument, which represents data to be sent to the worker. The data may
* be any primitive type value or `JSON`. Call of this method asynchronously
* emits `message` event with data value in the global scope of this
* worker.
*
* `message` event listeners can be set either by calling
* `self.on` with a first argument string `"message"` or by
* implementing `onMessage` function in the global scope of this worker.
* @param {Number|String|JSON} data
*/
postMessage: function (...data) {
let model = modelFor(this);
let args = ['message'].concat(data);
if (!model.inited) {
model.earlyEvents.push(args);
return;
}
processMessage.apply(null, [this].concat(args));
},
get url () {
let model = modelFor(this);
// model.window will be null after detach
return model.window ? model.window.document.location.href : null;
},
get contentURL () {
let model = modelFor(this);
return model.window ? model.window.document.URL : null;
},
// Implemented to provide some of the previous features of exposing sandbox
// so that Worker can be extended
getSandbox: function () {
return modelFor(this).contentWorker;
},
toString: function () { return '[object Worker]'; },
attach: method(attach),
detach: method(detach),
destroy: method(destroy)
});
exports.Worker = Worker;
attach.define(Worker, function (worker, window) {
let model = modelFor(worker);
model.window = window;
// Track document unload to destroy this worker.
// We can't watch for unload event on page's window object as it
// prevents bfcache from working:
// https://developer.mozilla.org/En/Working_with_BFCache
model.windowID = getInnerId(model.window);
events.on("inner-window-destroyed", model.documentUnload);
// will set model.contentWorker pointing to the private API:
model.contentWorker = WorkerSandbox(worker, model.window);
// Listen to pagehide event in order to freeze the content script
// while the document is frozen in bfcache:
model.window.addEventListener("pageshow", model.pageShow, true);
model.window.addEventListener("pagehide", model.pageHide, true);
// Mainly enable worker.port.emit to send event to the content worker
model.inited = true;
model.frozen = false;
// Fire off `attach` event
emit(worker, 'attach', window);
// Process all events and messages that were fired before the
// worker was initialized.
model.earlyEvents.forEach(args => processMessage.apply(null, [worker].concat(args)));
});
/**
* Remove all internal references to the attached document
* Tells _port to unload itself and removes all the references from itself.
*/
detach.define(Worker, function (worker, reason) {
let model = modelFor(worker);
// maybe unloaded before content side is created
if (model.contentWorker) {
model.contentWorker.destroy(reason);
}
model.contentWorker = null;
if (model.window) {
model.window.removeEventListener("pageshow", model.pageShow, true);
model.window.removeEventListener("pagehide", model.pageHide, true);
}
model.window = null;
// This method may be called multiple times,
// avoid dispatching `detach` event more than once
if (model.windowID) {
model.windowID = null;
events.off("inner-window-destroyed", model.documentUnload);
model.earlyEvents.length = 0;
emit(worker, 'detach');
}
model.inited = false;
});
isPrivate.define(Worker, ({ tab }) => isPrivate(tab));
/**
* Tells content worker to unload itself and
* removes all the references from itself.
*/
destroy.define(Worker, function (worker, reason) {
detach(worker, reason);
modelFor(worker).inited = true;
// Specifying no type or listener removes all listeners
// from target
off(worker);
off(worker.port);
});
/**
* Events fired by workers
*/
function documentUnload ({ subject, data }) {
let model = modelFor(this);
let innerWinID = subject.QueryInterface(Ci.nsISupportsPRUint64).data;
if (innerWinID != model.windowID) return false;
detach(this);
return true;
}
function pageShow () {
let model = modelFor(this);
model.contentWorker.emitSync('pageshow');
emit(this, 'pageshow');
model.frozen = false;
}
function pageHide () {
let model = modelFor(this);
model.contentWorker.emitSync('pagehide');
emit(this, 'pagehide');
model.frozen = true;
}
/**
* Fired from postMessage and emitEventToContent, or from the earlyMessage
* queue when fired before the content is loaded. Sends arguments to
* contentWorker if able
*/
function processMessage (worker, ...args) {
let model = modelFor(worker) || {};
if (!model.contentWorker)
throw new Error(ERR_DESTROYED);
if (model.frozen)
throw new Error(ERR_FROZEN);
model.contentWorker.emit.apply(null, args);
}
function createModel () {
return {
// List of messages fired before worker is initialized
earlyEvents: [],
// Is worker connected to the content worker sandbox ?
inited: false,
// Is worker being frozen? i.e related document is frozen in bfcache.
// Content script should not be reachable if frozen.
frozen: true,
/**
* Reference to the content side of the worker.
* @type {WorkerGlobalScope}
*/
contentWorker: null,
/**
* Reference to the window that is accessible from
* the content scripts.
* @type {Object}
*/
window: null
};
}
function createPort (worker) {
let port = EventTarget();
port.emit = emitEventToContent.bind(null, worker);
return port;
}
/**
* Emit a custom event to the content script,
* i.e. emit this event on `self.port`
*/
function emitEventToContent (worker, ...eventArgs) {
let model = modelFor(worker);
let args = ['event'].concat(eventArgs);
if (!model.inited) {
model.earlyEvents.push(args);
return;
}
processMessage.apply(null, [worker].concat(args));
}