Rails environment setup and update script

I'm about to embark on creating a script/system for keeping a project's Rails and related environment up to date, as well as doing an initial setup. Gems and various Rails pieces already can do some auto-update and setup things, but I'm wanting something more professional, and something more explicit and exact in terms of versions used.

The idea is that this system will take a bare bones machine from essentially just having an OS, to full development or production ready. And then also, once set up, it will update it. So, it will install Ruby, Rails, Gems, database of choice, libraries needed (e.g. ImageMagick), other components used (e.g. DarwinPorts), etc. In combination with the source code control system (SCCM) (such as Perforce or Subversion), it will keep each piece up to date.

In addition, it will do things like install gems and other pieces from what you store in your SCCM - not just from the net or by doing say a generic "gem update". The reason to do this is that you can track the exact versions used at any given point in your application's development or deployment. You won't have to somehow separately document that you were using XYZ versions when you deployed 2.1.3 of your app, etc. I've used, and have heard others who take this further in the past, by also putting even the OS, development tools, and so on withint he source control system (I've never done the OS part, but I believe at Siemens they used to do that back in MacOS <= 9 days). This script also helps ensure all developers and deployment systems are in sync. At the moment I'm planning to do this with a bootstrap bash shell script, but then once Ruby is available, it'd kick over to a Rake script. Partly I'm choosing this route as a way to learn more about Rake. I'd be interested in hearing if anyone else has such a system in place, or if there's already something out there for this (that works well with Ruby and Rails).

Update: I forgot one other thing that plays in here. Our firewall rules at work do not allow rsync outside the firewall. This prevents things like DarwinPorts from working. The solution, silly as it is, is to take a laptop home, connect to a non-VPN'ed network, and do your DarwinPorts work. Then, you come back, and the ports themselves are cached, so you can then add them to your SCCM and install from there for other machines (who wants to lug a super heavy G5 home, ya, not me).

Tags: Ruby, RubyOnRails, Rake, Automation, Versioning