Posts in July, 2009

An ETag is a feature of HTTP that allows for a web server to know if content has changed since the last time the browser visited the page. The client sends the ETag from the cached page in a header. If the ETag in the header matches the current ETag then the server lets the browser know that the cached is up-to-date by sending back a 304 Not Modified response.

The most natural way to build an ETag is to generate it from the HTML returned by the view, which I believe is how the default view caching works in Django. The downside of this is that the page is generated even if the client has a cached copy, and all that is saved is the cost of sending the page to the client. continue reading…

Here's an interesting bit of Python code I hacked together – it's a script that takes an image and warps it so that it is tileable (making it suitable for a repeating backgound or a texture in a game).

A Mandlebrot fractal

If you use it on a photograph, it will come out looking like a fair-ground mirror. But it works well when applied to a pattern, or something more abstract, such as the fractal image on the left.

The code is public domain – use it for whatever the heck you want!

Update: Here's another, more interesting example, The original is here.

My employer is looking for a new Python developer to work here in Oxford, UK. The company I work for runs, which is collaboration service for sustainable business. Basically, it's a social networking type of site for businesses to collaborate on climate change and related issues. I'm not officially allowed to say this, but the closest analogy is ‘Facebook for Businesses’.

This is the office. Ignore the man in the far corner, he is just a hobo that wandered in.

The site is built with Django, so obviously Django experience would be a bonus, but experience with any MVC framework would be valuable. We're looking for someone who isn't necessarily a specialist and who doesn't mind getting to grips with new technology and dabbling in the front-end from time to time. continue reading…

Here's the most convoluted “Hello World!” script I could come up with (in response to this). I don't know if it works. I've proven it correct, but I haven't tested it.

I promise my production code is (marginally) more readable this this…