Beta Browsers 2008

This is a big year. Both IE and Firefox will release new versions this year. That hasn't happened ... ever? IE8 had its first beta, whereas Firefox 3 is at beta four. Indeed FF3 is much more polished at this point than IE8. However, I must say that Microsoft has been smarter than the Firefox team in a number of ways.

First, IE8 includes an improved IE Developer Toolbar by default. The IE DevBar is roughly equivalent to Firebug, but Firebug does not work with FF3. Of course you can’t really blame this on FF, but IE8 is much more web developer friendly. Web developers are the primary (only?) audience for beta browsers. IE8 also includes the IE7 emulation mode. Again this is very nice for web developers who have to program for IE7 currently, but need to get a head start on IE8 (wait, isn’t that all web developers?)

Google Web Toolkit and Firebug

Today I was working on a small web application that uses the Google Web Toolkit. I think a lot of the appeal of GWT is that Java developers have distaste for JavaScript. So what do they do? They build a framework to generate all the ugly JS for them.

I like JavaScript, and I'm not worried that saying so will cause me to take a pay-cut. I have some tools I like to use to deal with it. One is a bookmarklet I found for viewing XMLHttpRequests and responses. It works really well in Internet Explorer 7.

I was playing with my little app on IE, and decided to open up my bookmarklet to see exactly what the GWT-generated JavaScript sent to the server. What did I see? Nothing at all...

Ok, time to get serious. I switched over to Firefox, where I have every web developer's best friend, Firebug, installed. I flipped the switch on Firebug and repeated the same process. What did I see here? Again nothing. Nada.

What the heck was going on? I see the request hitting the server and the response causing the data on the page to be changed. Yet somehow these common debugging tools were oblivious to what was going on. Was there an inviso-IFrame being used? That would be so Web 1.0-ish.

I probed around with Firebug, and indeed there was a massive hidden IFrame on my page. I opened it up and saw that there was a GWT-generated HTML page that was being dumped in here. That page contained tons of JavaScript. And not just any JavaScript, but amazingly obfuscated JavaScript. Here's a sample of it:

function gX(hX,iX){hX.aX = iX;}
function jX(kX){return kX.cX;}
function lX(mX,nX){mX.cX = nX;}
function oX(pX){return pX.bX;}
function qX(rX,sX){rX.bX = sX;}
function tX(uX,vX){uX.fo(eX(vX));uX.cq(jX(vX));uX.fo(oX(vX));}
function wX(xX,yX){gX(yX,xX.jo());lX(yX,xX.Ep());qX(yX,xX.jo());}

I don't know what to say about this stuff, but it's not the point. This wacky IFrame was where all the magic happened. It's the use of this IFrame and its Skynet-like JS that allows the GWT guys to claim:

Your GWT applications automatically support IE, Firefox, Mozilla, Safari, and Opera with no browser detection or special-casing within your code in most cases.

They're not using the sexiest flavor of AJAX, they're using the lowest-common-denominator version of it.