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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 {
TYPES: { DOCUMENT_EVENT },
const isEveryFrameTargetEnabled = Services.prefs.getBoolPref(
"devtools.every-frame-target.enabled",
false
);
const {
WILL_NAVIGATE_TIME_SHIFT,
class ParentProcessDocumentEventWatcher {
/**
* Start watching, from the parent process, for DOCUMENT_EVENT's "will-navigate" event related to a given Watcher Actor.
*
* All other DOCUMENT_EVENT events are implemented from another watcher class, running in the content process.
* Note that this other content process watcher will also emit one special edgecase of will-navigate
* retlated to the iframe dropdown menu.
*
* We have to move listen for navigation in the parent to better handle bfcache navigations
* and more generally all navigations which are initiated from the parent process.
* 'bfcacheInParent' feature enabled many types of navigations to be controlled from the parent process.
*
* This was especially important to have this implementation in the parent
* because the navigation event may be fired too late in the content process.
* Leading to will-navigate being emitted *after* the new target we navigate to is notified to the client.
*
* @param WatcherActor watcherActor
* The watcher actor from which we should observe document event
* @param Object options
* Dictionary object with following attributes:
* - onAvailable: mandatory function
* This will be called for each resource.
*/
async watch(watcherActor, { onAvailable }) {
this.watcherActor = watcherActor;
this.onAvailable = onAvailable;
// List of listeners keyed by innerWindowId.
// Listeners are called as soon as we emitted the will-navigate
// resource for the related WindowGlobal.
this._onceWillNavigate = new Map();
// Filter browsing contexts to only have the top BrowsingContext of each tree of BrowsingContexts…
const topLevelBrowsingContexts = this.watcherActor
.getAllBrowsingContexts()
.filter(browsingContext => browsingContext.top == browsingContext);
// Only register one WebProgressListener per BrowsingContext tree.
// We will be notified about children BrowsingContext navigations/state changes via the top level BrowsingContextWebProgressListener,
// and BrowsingContextWebProgress.browsingContext attribute will be updated dynamically everytime
// we get notified about a child BrowsingContext.
// Note that regular web page toolbox will only have one BrowsingContext tree, for the given tab.
// But the Browser Toolbox will have many trees to listen to, one per top-level Window, and also one per tab,
// as tabs's BrowsingContext context aren't children of their top level window!
//
// Also save the WebProgress and not the BrowsingContext because `BrowsingContext.webProgress` will be undefined in destroy(),
// while it is still valuable to call `webProgress.removeProgressListener`. Otherwise events keeps being notified!!
this.webProgresses = topLevelBrowsingContexts.map(
browsingContext => browsingContext.webProgress
);
this.webProgresses.forEach(webProgress => {
webProgress.addProgressListener(
this,
Ci.nsIWebProgress.NOTIFY_STATE_DOCUMENT
);
});
}
/**
* Wait for the emission of will-navigate for a given WindowGlobal
*
* @param Number innerWindowId
* WindowGlobal's id we want to track
* @return Promise
* Resolves immediatly if the WindowGlobal isn't tracked by any target
* -or- resolve later, once the WindowGlobal navigates to another document
* and will-navigate has been emitted.
*/
onceWillNavigateIsEmitted(innerWindowId) {
// Only delay the target-destroyed event if the target is for BrowsingContext for which we will emit will-navigate
const isTracked = this.webProgresses.find(
webProgress =>
webProgress.browsingContext.currentWindowGlobal.innerWindowId ==
innerWindowId
);
if (isTracked) {
return new Promise(resolve => {
this._onceWillNavigate.set(innerWindowId, resolve);
});
}
return Promise.resolve();
}
onStateChange(progress, request, flag) {
const isStart = flag & Ci.nsIWebProgressListener.STATE_START;
const isDocument = flag & Ci.nsIWebProgressListener.STATE_IS_DOCUMENT;
if (isDocument && isStart) {
const { browsingContext } = progress;
// Ignore navigation for same-process iframes when EFT is disabled
if (
!browsingContext.currentWindowGlobal.isProcessRoot &&
!isEveryFrameTargetEnabled
) {
return;
}
// Ignore if we are still on the initial document,
// as that's the navigation from it (about:blank) to the actual first location.
// The target isn't created yet.
if (browsingContext.currentWindowGlobal.isInitialDocument) {
return;
}
// Only emit will-navigate for top-level targets.
if (
this.watcherActor.sessionContext.type == "all" &&
browsingContext.isContent
) {
// Never emit will-navigate for content browsing contexts in the Browser Toolbox.
// They might verify `browsingContext.top == browsingContext` because of the chrome/content
// boundary, but they do not represent a top-level target for this DevTools session.
return;
}
const isTopLevel = browsingContext.top == browsingContext;
if (!isTopLevel) {
return;
}
const newURI = request instanceof Ci.nsIChannel ? request.URI.spec : null;
const { innerWindowId } = browsingContext.currentWindowGlobal;
this.onAvailable([
{
browsingContextID: browsingContext.id,
innerWindowId,
resourceType: DOCUMENT_EVENT,
name: "will-navigate",
time: Date.now() - WILL_NAVIGATE_TIME_SHIFT,
isFrameSwitching: false,
newURI,
},
]);
const callback = this._onceWillNavigate.get(innerWindowId);
if (callback) {
this._onceWillNavigate.delete(innerWindowId);
callback();
}
}
}
get QueryInterface() {
return ChromeUtils.generateQI([
"nsIWebProgressListener",
"nsISupportsWeakReference",
]);
}
destroy() {
this.webProgresses.forEach(webProgress => {
webProgress.removeProgressListener(
this,
Ci.nsIWebProgress.NOTIFY_STATE_DOCUMENT
);
});
this.webProgresses = null;
}
}
module.exports = ParentProcessDocumentEventWatcher;