Sysconfig's Blog » Development

Why do Twitter clients use Adobe AIR?

admin — Sun, 21 Jun 2009 11:56:50 +0000

@tkramar raised the question on Twitter, why every desktop client for that service seems to be built on top of Adobe Air (here). That’s something, I also was wondering about. And in fact you often hear people complain: “Why AIR? Why not a native application?” Let me try to give the answer while having breakfast.

First we need to look at what Adobe Air is: It is a run-time environment, ported to all common operating systems, which allows to run applications built with Adobe Flex on almost any desktop rather than embedded with a browser (where you can run the same applications with little or no modifications using the well-known Flash Player Plugin).

So, we know that AIR developers use Flex. Why is that? That’s as easy to answer: Flex targets front-end/GUI designers in the first place. Together with Flex, Actionscript, and Flash, you can build quite neat and shiny user interfaces. Most of the “business logic” (I know that sounds funny in this context) is not part of it though. The strength of Flex is to use external data sources like web services. On the one hand, it’s certainly a limitation, but on the other hand that’s exactly why it’s being used for Twitter clients, which don’t do much more than using Twitter’s API (web service) to display tweets, subsets of tweets, search results, friends and stalkers (erm followers, of course).

So if you want to bring a desktop application to the market, which heavily depends on web services, Flex is probably one of the fastest ways to get there. And Adobe AIR brings the application to the desktop — on all common operating systems.

Yes, it’s proprietary software, and closed source. However, anyone can use it free of charge (the Flex SDK is free, the not required Adobe Flex Builder is not). Pretty similar to PDF and Flash. But the licensing policy is another discussion, anyway.

Octopus — Logging Server in C#

admin — Sat, 06 Jun 2009 19:21:21 +0000

I have to admit that I really like C#. The last 4 or 5 months, I’ve hardly touched any other programming language. And so it happened to be my first choice when I was asked to develop a “reasonably fast” logging server.

So what is this Octopus thing about? In a nutshell it’s a server, which takes HTTP requests with a defined set of URL parameters, confirms receipt the client, and then asynchronously stores the request into a database. The interesting bit is the part between accepting the request and storing it to the DB.

Basically, we’ve got three levels of storage: a in-memory queue, a flat file buffer, and the database. The tricky thing was to optimise processing, while still being fault-tolerant. I kind of managed that, I think. Octopus can (depending on the hardware it runs on) easily accept up to 2,000 requests per second, and will store them into either a MySQL or SQLite database at the moment. Please read more about it on the Octopus Website.

Waking up from hibernation

admin — Thu, 25 Sep 2008 23:01:41 +0000

After years of Systems Administration I have completely forgotten how much I used to like developing in Java. My current employer gave me that opportunity recently. So I took ownership and responsibility to de-hibernate myself (my Java knowledge became a bit rusty) and to start working on a project which separates the website’s business logic layer from the database layer. That becomes necessary as we want to re-design our infrastructure in a way that enables us to be as platform independent and as scalable as possible.

On the one hand, we are not even entirely sure if we’ll stick to MySQL or switch to any other DB server type, hence we must not use SQL dialect specific code within the application. On the other hand, we want to provide a SOAP endpoint internally, which allows us to access data from all sorts of applications and clearly separates the business logic of all sorts of clients from our actual data store.

In addition, caching of object structures which are mapped against data structures (or tables) would be very neat. Consequently, I suggested and started using Java with Hibernate and JAX-WS on a Glassfish Java Application Server. We might integrate an additional caching layer later. Terracotta is one of the candidates, which integrates seamlessly and can increase speed by factor 2 to 10.

After one week of researching, developing proofs of concept and presenting a first prototype, I am sooo excited about all that. I always loved Java, and again I remember why.