blob: 84a639ef339a1f8e6f66088780521c1ca175ab68 [file] [log] [blame]
/*
* Copyright (C) 2013 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
* THE POSSIBILITY OF SUCH DAMAGE.
*/
WI.DOMTree = class DOMTree extends WI.Object
{
constructor(frame)
{
super();
this._frame = frame;
this._rootDOMNode = null;
this._requestIdentifier = 0;
this._frame.addEventListener(WI.Frame.Event.PageExecutionContextChanged, this._framePageExecutionContextChanged, this);
WI.domTreeManager.addEventListener(WI.DOMTreeManager.Event.DocumentUpdated, this._documentUpdated, this);
// Only add extra event listeners when not the main frame. Since DocumentUpdated is enough for the main frame.
if (!this._frame.isMainFrame()) {
WI.domTreeManager.addEventListener(WI.DOMTreeManager.Event.NodeRemoved, this._nodeRemoved, this);
this._frame.addEventListener(WI.Frame.Event.MainResourceDidChange, this._frameMainResourceDidChange, this);
}
}
// Public
get frame() { return this._frame; }
disconnect()
{
WI.domTreeManager.removeEventListener(null, null, this);
this._frame.removeEventListener(null, null, this);
}
invalidate()
{
// Set to null so it is fetched again next time requestRootDOMNode is called.
this._rootDOMNode = null;
// Clear the pending callbacks. It is the responsibility of the client to listen for
// the RootDOMNodeInvalidated event and request the root DOM node again.
this._pendingRootDOMNodeRequests = null;
if (this._invalidateTimeoutIdentifier)
return;
function performInvalidate()
{
this._invalidateTimeoutIdentifier = undefined;
this.dispatchEventToListeners(WI.DOMTree.Event.RootDOMNodeInvalidated);
}
// Delay the invalidation on a timeout to coalesce multiple calls to invalidate.
this._invalidateTimeoutIdentifier = setTimeout(performInvalidate.bind(this), 0);
}
requestRootDOMNode(callback)
{
console.assert(typeof callback === "function");
if (typeof callback !== "function")
return;
if (this._rootDOMNode) {
callback(this._rootDOMNode);
return;
}
if (!this._frame.isMainFrame() && !this._frame.pageExecutionContext) {
this._rootDOMNodeRequestWaitingForExecutionContext = true;
if (!this._pendingRootDOMNodeRequests)
this._pendingRootDOMNodeRequests = [];
this._pendingRootDOMNodeRequests.push(callback);
return;
}
if (this._pendingRootDOMNodeRequests) {
this._pendingRootDOMNodeRequests.push(callback);
return;
}
this._pendingRootDOMNodeRequests = [callback];
this._requestRootDOMNode();
}
// Private
_requestRootDOMNode()
{
console.assert(this._frame.isMainFrame() || this._frame.pageExecutionContext);
console.assert(this._pendingRootDOMNodeRequests.length);
// Bump the request identifier. This prevents pending callbacks for previous requests from completing.
var requestIdentifier = ++this._requestIdentifier;
function rootObjectAvailable(error, result)
{
// Check to see if we have been invalidated (if the callbacks were cleared).
if (!this._pendingRootDOMNodeRequests || requestIdentifier !== this._requestIdentifier)
return;
if (error) {
console.error(JSON.stringify(error));
this._rootDOMNode = null;
dispatchCallbacks.call(this);
return;
}
// Convert the RemoteObject to a DOMNode by asking the backend to push it to us.
var remoteObject = WI.RemoteObject.fromPayload(result);
remoteObject.pushNodeToFrontend(rootDOMNodeAvailable.bind(this, remoteObject));
}
function rootDOMNodeAvailable(remoteObject, nodeId)
{
remoteObject.release();
// Check to see if we have been invalidated (if the callbacks were cleared).
if (!this._pendingRootDOMNodeRequests || requestIdentifier !== this._requestIdentifier)
return;
if (!nodeId) {
this._rootDOMNode = null;
dispatchCallbacks.call(this);
return;
}
this._rootDOMNode = WI.domTreeManager.nodeForId(nodeId);
console.assert(this._rootDOMNode);
if (!this._rootDOMNode) {
dispatchCallbacks.call(this);
return;
}
// Request the child nodes since the root node is often not shown in the UI,
// and the child nodes will be needed immediately.
this._rootDOMNode.getChildNodes(dispatchCallbacks.bind(this));
}
function mainDocumentAvailable(document)
{
this._rootDOMNode = document;
dispatchCallbacks.call(this);
}
function dispatchCallbacks()
{
// Check to see if we have been invalidated (if the callbacks were cleared).
if (!this._pendingRootDOMNodeRequests || requestIdentifier !== this._requestIdentifier)
return;
for (var i = 0; i < this._pendingRootDOMNodeRequests.length; ++i)
this._pendingRootDOMNodeRequests[i](this._rootDOMNode);
this._pendingRootDOMNodeRequests = null;
}
// For the main frame we can use the more straight forward requestDocument function. For
// child frames we need to do a more roundabout approach since the protocol does not include
// a specific way to request a document given a frame identifier. The child frame approach
// involves evaluating the JavaScript "document" and resolving that into a DOMNode.
if (this._frame.isMainFrame())
WI.domTreeManager.requestDocument(mainDocumentAvailable.bind(this));
else {
var contextId = this._frame.pageExecutionContext.id;
RuntimeAgent.evaluate.invoke({expression: appendWebInspectorSourceURL("document"), objectGroup: "", includeCommandLineAPI: false, doNotPauseOnExceptionsAndMuteConsole: true, contextId, returnByValue: false, generatePreview: false}, rootObjectAvailable.bind(this));
}
}
_nodeRemoved(event)
{
console.assert(!this._frame.isMainFrame());
if (event.data.node !== this._rootDOMNode)
return;
this.invalidate();
}
_documentUpdated(event)
{
this.invalidate();
}
_frameMainResourceDidChange(event)
{
console.assert(!this._frame.isMainFrame());
this.invalidate();
}
_framePageExecutionContextChanged(event)
{
if (this._rootDOMNodeRequestWaitingForExecutionContext) {
console.assert(this._frame.pageExecutionContext);
console.assert(this._pendingRootDOMNodeRequests && this._pendingRootDOMNodeRequests.length);
this._rootDOMNodeRequestWaitingForExecutionContext = false;
this._requestRootDOMNode();
}
}
};
WI.DOMTree.Event = {
RootDOMNodeInvalidated: "dom-tree-root-dom-node-invalidated",
};