Skip to main content

De-obfuscating javascript code in Chrome Developer Tools

I had blogged about JavaScript debugging with Chrome Developer Tools some time back, wherein I have explained how these developer tools can help in debugging javascript code. Today Google Chrome 12 was released and my Chrome browser was updated to this version. As with every release, there have been some improvements made on performance, usability etc,. One feature that stood out for me is the ability to De-obfuscate the javascript code.

What is Minification?

Minification is the process of removing unnecessary characters such as white spaces, comments, new lines from the source code. These otherwise would be added to make the code more readable. Minifying the source code helps in reducing the file size and thereby reducing the time taken to download the file. This is the reason why most of the popular javascript libraries such as jQuery are minified. A minified jQuery file is of 31 KB in size where as an uncompressed one is about 229 KB. Unfortunately, debugging minified javascript files is an impossible task.

With the latest version of Google Chrome one can choose to de-obfuscate the javascript code right with in the developer tools. This is how the jquery.js file would look before de-obfuscation:



Now, to de-obfuscate the code one can right click on the file and select the 'De-obfuscate Source' option. This would de-obfuscate the javascript code and present the code which is readable and ready to debug:



Update:

This post was written when Chrome 12 was released. In recent versions, this option is available as a button - 'pretty print', at the bottom left corner of the screen. Look for the button with the icon '{ }'.


Labels:

Comments

  1. Exist-DissolveJune 17, 2011 at 9:09 PM

    I don't have an option for de-obfuscating the code, but I do have a new "Pretty Print" option next to the Pause Exceptions option. Seems to do the same thing.

    ReplyDelete
  2. Sagar GanatraJune 17, 2011 at 9:45 PM

    You can right click anywhere on the javaScript and you should have 'De-obfuscate Source' option there. Are you on Chrome 12?

    ReplyDelete
  3. Exist-DissolveJune 17, 2011 at 11:40 PM

    Ah, nevermind. I'm on 14

    ReplyDelete
  4. Adelein RodriguezAugust 9, 2011 at 6:48 AM

    in chrome 13 and above it is a { } on the bottom right corner of the screen

    ReplyDelete
  5. Sagar GanatraAugust 9, 2011 at 9:37 AM

    @Adelein,

    You're right, they have now provided the option pretty print.

    ReplyDelete
  6. AnonymousOctober 18, 2011 at 5:12 AM

    Oops, that's *bottom left* .. the curly brackets :)

    ReplyDelete
  7. Sagar GanatraOctober 18, 2011 at 9:22 AM

    I have update the post with the option available in recent version.

    ReplyDelete

Post a Comment

Popular posts from this blog

How to use the APP_INITIALIZER token to hook into the Angular bootstrap process

I've been building applications using Angular as a framework of choice for more than a year and this post is not about another React vs Angular or the quirks of each framework. Honestly, I like Angular and every day I discover something new which makes development easier and makes me look like a guy who built something very complex in a matter of hours which would've taken a long time to put the correct architecture in place if I had chosen a different framework. The first thing that I learned in Angular is the use of the APP_INITIALIZER token.
Post a Comment
Read more

On GraphQL and building an application using React Apollo

When I visualize building an application, I would think of using React and Redux on the front-end which talks to a set of RESTful services built with Node and Hapi (or Express). However, over a period of time, I've realized that this approach does not scale well when you add new features to the front-end. For example, consider a page that displays user information along with courses that a user has enrolled in. At a later point, you decide to add a section that displays popular book titles that one can view and purchase. If every entity is considered as a microservice then to get data from three different microservices would require three http  requests to be sent by the front-end app. The performance of the app would degrade with the increase in the number of http requests. I read about GraphQL and knew that it is an ideal way of building an app and I need not look forward to anything else. The GraphQL layer can be viewed as a facade which sits on top of your RESTful services o...
Post a Comment
Read more

Using MobX to manage application state in a React application

I have been writing applications using React and Redux for quite some time now and thought of trying other state management solutions out there. It's not that I have faced any issues with Redux; however, I wanted to explore other approaches to state management. I recently came across MobX  and thought of giving it a try. The library uses the premise of  `Observables` to tie the application state with the view layer (React). It's also an implementation of the Flux pattern wherein it uses multiple stores to save the application state; each store referring to a particular entity. Redux, on the other hand, uses a single store with top-level state variables referring to various entities.
Post a Comment
Read more