Google closed source app engine does evil

David M Williams
Wednesday, 16 April 2008 15:03

Opinion and Analysis

The SDK contains a tool to upload apps to the App Engine site. You also have access to a web based administrator console which promises to help you manage your domains, turn apps on and off, browse the data store, check logs and do more things. Alas, the URL is broken and – at the time of writing – “The requested URL /appengine/theadminconsole.html was not found on this server.”

So far you might think this is pretty cool. And really, Google are giving an impressive offering. Let’s get technical: the app engine fits in a category called the cloud computing platform market. Fundamentally, this means it’s an offering on the Internet – the cloud – which you can program yourself – making it a platform. This market reflects the evolutionary nature of the web.

Mark Andreessen expounds on his perceived three kinds, or levels, of platforms on the Internet. To him level one is a web services API; you execute your code somewhere and make a call over the Internet to access the platform. You get data or a service and keep on doing your own thing. This is a pretty common model; many big name web sites expose a web services API including eBay and PayPal. However, the downside is developers still have to have a server, bandwidth, security and the like. Andreessen postulates the uptake of web services APIs has been low as a consequence of the high technical and financial resources required.

Level 2 platforms are plug-in APIs. Plug-ins are nothing new, Netscape had them. Photoshop has them. Firefox does it. Turning back to Facebook this is really the type of app you write for it; your program plugs in to Facebook and shows within its user experience and enhances the experience of that parent program.

If a third-party plugin is down it shows as an error within the core system; that looks bad. By the same token, if the plugin is highly successful the developer can be swamped by their success as I touched on earlier.

Moving up the scale we come to level 3 platforms. This time the third-party code runs within the platform. It’s totally online. Developers don’t need any storage or servers or bandwidth of their own.

However, the downsides add up. Concluding with Andreessen, he makes a vital comment about level 3 platforms. The vendor has to commit to never killing it off. Think about it: if a level 1 or level 2 platform ever gets killed you still have a working and useful system. Imagine if Facebook killed off their plug-in mechanism. You’d still have Facebook which works, even if it had less ninjas and pirates consuming the world’s collective time.

If you kill a level 3 platform you destroy the whole reason people use your system. Applications won’t run if the platform is removed. This is true of Google’s App Engine.

What’s also true is that the App Engine limits what you are able to achieve; the simple deployment comes at a restrictive cost. I’ve already said it comes with just one language and it doesn’t offer any background processes. This last point can’t be underestimated. Most every reasonably sized application has to do stuff in the background – be it nightly batch processing or even just consuming data while still providing a responsive UI. At one extreme you have systems running cron jobs, at another end you have the rise of Ajax in web pages which fundamentally aims at giving alacrity to the web.

There’s also something more important. Something which open source developers will hold dear. Please read on.

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