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Debugging JavaScript in client

I'm facing an issue while debugging my application. Following is the architecture:
Server: Java (Servlet)
Client: React+D3
Problem: Whenever, I change some react or d3 code and if an error occurs then it just shows me that some react (or d3) error has occurred but never tells me which function the error occurred (as seen in snapshot). Now, I know that simply debugging it by having the information like variable name and searching where I defined that variable. However, situation becomes tough when I use same object multiple times (say window) and had made several changes in the code. In this case, a specific line number where the error occured can be handy and quick. Let me know if I'm missing some basics about debugging such applications?
EDIT1:
1. In the snapshot, http://localhost:8080/..../Server Server is the main servlet application, kind of launchpad, which triggers several other react-based js files.
2. The mentioned ReferenceError is inside a function updateWindow() but the console never mentions this (and that's my problem).
PS: I'm using Eclipse tomcat on server-side

I think there's no straight forward solution to this problem. So, I'll post the method that worked for me with few additional points:
Problem: It doesn't gives a nice error trace like standard Java application, probably because it mixes with JavaScript code.
At every line of the error trace, line:column specifies the error line. I used this as a reference and started manual debugging from where my application launches i.e. Server.java and look where I defined the createChart() in the JS file and drill-down until I found the referenced variable.
In case of ReactJS' error (an error after resolving reference issue), I debugged it with normal react.js (not minified version react.min.js) so that it shows me exact line of error. Minified version is cluttered and is useless while debugging.
PS: If someone has better answer I'll edit this in future.

SonarQube, sonar-javascript and JSTestDriver - ressource not found

I need your help/guidance about one problem I have for the last two days.
The sonar-javascript plugin is not able to get the results of my Javascript UnitTests. I am generating unit tests and lcov results using JSTestDriver. The lcov results are working and are correctly shown in SonarQube. I also have to say that I am using Windows. Here is the error I have:
Test result will not be saved for test class "UnitTests.controlesTest", because SonarQube associated resource has not been found using file name: UnitTests\controlesTest.js"
The error is very similar to this one: Importing javascript XML JUnit tests to sonar using jstestdriver fails. However, this error seems to be fixed in the last SNAPSHOT (2.8). The file I am trying to access is stored in UnitTests/controlesTest.js. I tried to go into the sonar-javascript source, and find a way to correct this issue (at least, try to understand it). I ended up in the file JsTestDriverSensor.java in the function getTestFileRelativePathToBaseDir. I found that this line is not able to get my file (UnitTests\controles.js). Actually, fileIterator does not contain any InputFile.
Iterator<InputFile> fileIterator = fileSystem.inputFiles(predicate).iterator();
So I tried different predicates to understand why my file is not found. At the end, I found that the following predicate fileSystem.predicates().hasType(InputFile.Type.TEST) is the reason why this file is not found. A quick fix is to change:
- 108 testFilePredicate,
+ 108 mainFilePredicate,
I must be doing something wrong, maybe someone has an idea ?

The "sonar.tests" property has to be set in the sonar-project.properties (or in newer version SonarQube.Analysis.xml). This allows the sonar-javascript plugin to find the javascript test files.

how do you allow javascript communications with Flex/Flash/Actionscript

Well here's a problem.
I've got a website with large javascript backend. This backend talks to a server over a socket with a socket bridge using http://blog.deconcept.com/swfobject/
The socket "bridge" is a Flex/Flash .swf application/executable/plugin/thing for which the source is missing.
I've got to change it.
More facts:
file appExePluginThing.swf
appExePluginThing.swf Macromedia Flash data (compressed), version 9
I've used https://www.free-decompiler.com/flash/ to decompile the .swf file and I think I've sorted out what's the original code vs the libraries and things Flash/Flex built into it.
I've used FDT (the free version) to rebuild the decompiled code into MYappExePluginThing.swf so I can run it with the javascript code and see what happens.
I'm here because what happens isn't good. Basically, my javascript code (MYjavascript.js) gets to the point where it does
window.log("init()");
var so = new SWFObject("flash/MYappExePluginThing.swf"", socketObjectId, "0", "0", "9", "#FFFFFF");
window.log("init() created MYappExecPluginThing!!!");
so.addParam("allowScriptAccess", "always");
log("init() added Param!!");
so.write(elId);
log("init() wrote!");
IE9's console (yeah, you read that right) shows
init()
created MYappExecPluginThing!!!
init() added Param!!
init() wrote!
but none of the debugging i've got in MYappExePluginThing.as displays and nothing else happens.
I'm trying to figure out what I've screwed up/what's going on? Is MYappExePluginThing.as running? Is it waiting on something? Did it fail? Why aren't the log messages in MYappExePluginThing.as showing up?
The first most obvious thing is I'm using FDT which, I suspect, was not used to build the original. Is there some kind of magic "build javascript accessible swf thing" in FlashBuilder or some other IDE?
First noteworthy thing I find is:
file MYappExePluginThing.swf
MYappExePluginThing.swf Macromedia Flash data (compressed), version 14
I'm using Flex 4.6 which, for all I know, may have a completely different mechanism for allowing javascript communication than was used in appExePluginThing.swf
Does anyone know if that's true?
For example, when FDT runs this thing (I can compile but FDT does not create a .swf unless i run it) I get a warning in the following method:
private function init() : void
{
Log.log("console.log", "MYappExePluginThing init()");
//var initCallback:String = Application.application.parameters.initCallback?Application.application.parameters.initCallback:"MYjavascript.MYappExePluginThing_init";
var initCallback:String = FlexGlobals.topLevelApplication.parameters.initCallback?FlexGlobals.topLevelApplication.parameters.initCallback:"MYjavascript.MYappExePluginThing_init";
try
{
ExternalInterface.addCallback("method1Callback",method1);
ExternalInterface.addCallback("method2Callback",method2);
ExternalInterface.call(initCallback);
}
catch(err:Error)
{
Log.log("console.log", "MYappExePluginThing init() ERROR err="+err);
}
}
I got a warning that Application.application was deprecated and I should change:
var initCallback:String = Application.application.parameters.initCallback?Application.application.parameters.initCallback:"MYjavascript.MYappExePluginThing_init";
to:
var initCallback:String = FlexGlobals.topLevelApplication.parameters.initCallback?FlexGlobals.topLevelApplication.parameters.initCallback:"MYjavascript.MYappExePluginThing_init";
which I did but which had no effect on making the thing work.
(FYI Log.log() is something I added:
public class Log{
public static function log(dest:String, mssg:String):void{
if(ExternalInterface.available){
try{
ExternalInterface.call(dest, mssg);
}
catch(se:SecurityError){
}
catch(e:Error){
}
}
trace(mssg);
}
}
)
Additionally, in MYjavascript.js MYappExePluginThing_init looks like this:
this.MYappExePluginThing_init = function () {
log("MYjavascript.js - MYappExePluginThing_init:");
};
Its supposed to be executed when MYappExePluginThing finishes initializing itself.
Except its not. The message is NOT displaying on the console.
Unfortunately, I cannot find any references explaining how you allow javascript communication in Flex 4.6 so I can check if I've got this structured correctly.
Is it a built in kind of thing all Flex/Flash apps can do? Is my swf getting accessed? Is it having some kind of error? Is it unable to communicate back to my javascript?
Does anyone have any links to references?
If this was YOUR problem, what would you do next?

(Not a full solution but I ran out of room in the comment section.)
To answer your basic question, there's nothing special you should need to do to allow AS3-to-JS communication beyond what you've shown. However, you may have sandbox security issues on localhost; to avoid problems, set your SWFs as local-trusted (right-click Flash Player > Global Settings > Advanced > Trusted Location Settings). I'm guessing this not your problem, though, because you'd normally get a sandbox violation error.
More likely IMO is that something is broken due to decompilation and recompilation. SWFs aren't meant to do that, it's basically a hack made mostly possible due to SWF being an open format.
What I suggest is that you debug your running SWF. Using break-points and stepping through the code you should be able to narrow down where things are going wrong. You can also more easily see any errors your SWF is throwing.

Not really an answer, but an idea to get you started is to start logging everything on the Flash side to see where the breakage is.
Since you're using IE, I recommend getting the Debug flash player, installing it, then running Vizzy along side to show your traces.
Should give you a good idea of where the app is breaking down.
Vizzy
Debug Player

Why does html5 boilerplate use Twipsy and Prototype when it builds jQuery code?

So I just finished writing a single page with html5 boilerplate and everything is find with the dev code (the original one I just finished writing). Google Chrome and Firefox love it and display it well.
So I use the ant script ( ant build or ant text to skip jpeg/png optimization ) and browse to /publish/ to view it. And I got a javascript error :
Uncaught TypeError: Cannot read property 'Twipsy' of undefined
But the fact is I never used Twipsy or prototype, just jQuery ... so I run a javascript debug console and see in the generated javascript file a reference to Twipsy and Prototype. But I never use any of those in my code. So what's wrong ? and what can I do ?

Html5Boilerplate use a kind of very strong cache which actually keep the files you already delete in your project and always inline / include it in future build. You must delete publish and intermediate forlder to kepp your builder up to date.

WScript is undefined

I am trying to run a Javascript file locally, which is supposed to create a CSS image sprite using ImageMagick. It's part of the OpenID selector JS component: http://code.google.com/p/openid-selector/
The generate-sprite.js (http://code.google.com/p/openid-selector/source/browse/trunk/generate-sprite.js?r=140) file is supposed to create the image sprite automatically. However, whenever I run it in IE (the local version of the file, of course), I get the error SCRIPT5009: 'WScript' is undefined on line 19, character 1.
I have of course installed ImageMagick and updated the location in the js file. IE9 is letting the ActiveX execute.
Since I'm not familiar with WScript, I am completely lost. Googling didn't help, since this seems to be a very generic error.
Can somebody help diagnose this error please?

When you say you're "running" the JavaScript file locally, are you using Windows? If so, and double-clicking or typing the filename from the command line doesn't work, try:
wscript generate-sprite.js
...which explicitly invokes wscript.exe.
If you're not using Windows, you can't use that script — it relies on both Windows and Microsoft's JScript (which the wscript.exe program invokes).