Auto-Updating Systems via Subversion

March 8th, 2007

One technique that I've started to use a lot around the different systems here is to store everything in subversion. It's a pretty commonly recommended technique and the nicest benefit is that if your changes don't do what you wanted you can easily roll back to an earlier version.

I've found though, that my favorite benefit is that it makes it easy to set up automatic updates for systems. Generally I just add an 'svn update' as the first step in running the appropriate system. When that's not suitable, a simple cron job does the job just as well. For our cruise control server we actually have a "config" project which builds every 30 minutes and all it does is update cruise control's config files.

When you're dealing with windows servers remote log-ins can be difficult and even UNIX servers are annoying to SSH into across the pacific so being able to edit files locally and have them deploy automatically is a real time saver.

Java HTTP Caching Libraries?

March 8th, 2007

So I need to improve out caching support and I really don't want to got through all the pain myself if I can avoid it. Does anyone know of an existing library that just handles client-side caching with the appropriate If-None-Match and If-Not-Modified headers etc. We already have libraries for doing the actually HTTP stuff, I really just need something that knows how to store things on disk and tell me what headers to use to make the request conditional. Oh and we're an applet so small and without dynamic loading or configuration files would be ideal.

It seems to me that all the advice on caching around the web focuses on the server-side and assumes the only that that would ever do client-side caching is an existing browser. Not overly helpful.