Source code
Revision control
Copy as Markdown
Other Tools
/* 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
/* global ReactDOMServer, NewtabRenderUtils */
const PAGE_TEMPLATE_RESOURCE_PATH =
"resource://activity-stream/data/content/abouthomecache/page.html.template";
const SCRIPT_TEMPLATE_RESOURCE_PATH =
"resource://activity-stream/data/content/abouthomecache/script.js.template";
// If we don't stub these functions out, React throws warnings in the console
// upon being loaded.
let window = self;
window.requestAnimationFrame = () => {};
window.cancelAnimationFrame = () => {};
/* import-globals-from /toolkit/components/workerloader/require.js */
importScripts("resource://gre/modules/workers/require.js");
{
let oldChromeUtils = ChromeUtils;
// ChromeUtils is defined inside of a Worker, but we don't want the
// activity-stream.bundle.js to detect it when loading, since that results
// in it attempting to import JSMs on load, which is not allowed in
// a Worker. So we temporarily clear ChromeUtils so that activity-stream.bundle.js
// thinks its being loaded in content scope.
//
// eslint-disable-next-line no-implicit-globals, no-global-assign
ChromeUtils = undefined;
/* import-globals-from ../vendor/react.js */
/* import-globals-from ../vendor/react-dom.js */
/* import-globals-from ../vendor/react-dom-server.js */
/* import-globals-from ../vendor/redux.js */
/* import-globals-from ../vendor/react-transition-group.js */
/* import-globals-from ../vendor/prop-types.js */
/* import-globals-from ../vendor/react-redux.js */
/* import-globals-from ../data/content/activity-stream.bundle.js */
importScripts(
"resource://activity-stream/vendor/react.js",
"resource://activity-stream/vendor/react-dom.js",
"resource://activity-stream/vendor/react-dom-server.js",
"resource://activity-stream/vendor/redux.js",
"resource://activity-stream/vendor/react-transition-group.js",
"resource://activity-stream/vendor/prop-types.js",
"resource://activity-stream/vendor/react-redux.js",
"resource://activity-stream/data/content/activity-stream.bundle.js"
);
// eslint-disable-next-line no-global-assign, no-implicit-globals
ChromeUtils = oldChromeUtils;
}
let PromiseWorker = require("resource://gre/modules/workers/PromiseWorker.js");
let Agent = {
_templates: null,
/**
* Synchronously loads the template files off of the file
* system, and returns them as an object. If the Worker has loaded
* these templates before, a cached copy of the templates is returned
* instead.
*
* @return Object
* An object with the following properties:
*
* pageTemplate (String):
* The template for the document markup.
*
* scriptTempate (String):
* The template for the script.
*/
getOrCreateTemplates() {
if (this._templates) {
return this._templates;
}
const templateResources = new Map([
["pageTemplate", PAGE_TEMPLATE_RESOURCE_PATH],
["scriptTemplate", SCRIPT_TEMPLATE_RESOURCE_PATH],
]);
this._templates = {};
for (let [templateName, path] of templateResources) {
const xhr = new XMLHttpRequest();
// Using a synchronous XHR in a worker is fine.
xhr.open("GET", path, false);
xhr.responseType = "text";
xhr.send(null);
this._templates[templateName] = xhr.responseText;
}
return this._templates;
},
/**
* Constructs the cached about:home document using ReactDOMServer. This will
* be called when "construct" messages are sent to this PromiseWorker.
*
* @param state (Object)
* The most recent Activity Stream Redux state.
* @return Object
* An object with the following properties:
*
* page (String):
* The generated markup for the document.
*
* script (String):
* The generated script for the document.
*/
construct(state) {
// If anything in this function throws an exception, PromiseWorker
// runs the risk of leaving the Promise associated with this method
// forever unresolved. This is particularly bad when this method is
// called via AsyncShutdown, since the forever unresolved Promise can
// result in a AsyncShutdown timeout crash.
//
// To help ensure that no matter what, the Promise resolves with something,
// we wrap the whole operation in a try/catch.
try {
return this._construct(state);
} catch (e) {
console.error("about:home startup cache construction failed:", e);
return { page: null, script: null };
}
},
/**
* Internal method that actually does the work of constructing the cached
* about:home document using ReactDOMServer. This should be called from
* `construct` only.
*
* @param state (Object)
* The most recent Activity Stream Redux state.
* @return Object
* An object with the following properties:
*
* page (String):
* The generated markup for the document.
*
* script (String):
* The generated script for the document.
*/
_construct(state) {
state.App.isForStartupCache = true;
// ReactDOMServer.renderToString expects a Redux store to pull
// the state from, so we mock out a minimal store implementation.
let fakeStore = {
getState() {
return state;
},
dispatch() {},
};
let markup = ReactDOMServer.renderToString(
NewtabRenderUtils.NewTab({
store: fakeStore,
isFirstrun: false,
})
);
let { pageTemplate, scriptTemplate } = this.getOrCreateTemplates();
let cacheTime = new Date().toUTCString();
let page = pageTemplate
.replace("{{ MARKUP }}", markup)
.replace("{{ CACHE_TIME }}", cacheTime);
let script = scriptTemplate.replace(
"{{ STATE }}",
JSON.stringify(state, null, "\t")
);
return { page, script };
},
};
// This boilerplate connects the PromiseWorker to the Agent so
// that messages from the main thread map to methods on the
// Agent.
let worker = new PromiseWorker.AbstractWorker();
worker.dispatch = function (method, args = []) {
return Agent[method](...args);
};
worker.postMessage = function (result, ...transfers) {
self.postMessage(result, ...transfers);
};
worker.close = function () {
self.close();
};
self.addEventListener("message", msg => worker.handleMessage(msg));
self.addEventListener("unhandledrejection", function (error) {
throw error.reason;
});