Saturday, December 22, 2007

The power of checklists (especially when automated)

Just stumbled on this post at InfoQ on the power of checklists. It talks about a low-tech approach to improving care in hospitals, by writing down the steps needed in various medical procedures and putting together a checklist for each case. I've seen the power of this approach at my own company -- until we put together checklists with things we have to do when setting up various servers or applications, we were guaranteed to skip one or more small but important steps.

I'd like to take this approach up a notch though: if you're in the software business, you actually need to AUTOMATE your checklists. Otherwise it's still very easy for a human being to skip a step. Scripts don't usually make that mistake. Yes, a human being still needs to run the script and to make intelligent decisions about the overall outcome of its execution. If you do take this approach, make sure your scripts also have checks and balances embedded in them -- also known as tests. For example, if your script retrieves a file over the network with wget, make sure the file actually gets on your local file system. A simple 'ls' of the file will convince you that the operation succeeded.

As somebody else once said, the goal here is to replace you (the sysadmin or the developer) with a small script. That will free you up to do more fun work.

Wednesday, December 05, 2007

GHOP students ROCK!

I've been involved in the GHOP project for the last couple of weeks (although not as much as I'd have liked, due to time constraints) and I've been constantly amazed by the high quality of the work produced by the GHOP participants, who, let's not forget, are all still in high-school! I think all mentors were surprised at the speed with which the tasks were claimed, and at the level of proficiency showed by the students.

This bodes very well for Open Source in general, and for the Python community in particular. I hope that the students will continue to contribute to existing Python projects and start their own.

Here are some examples from tasks that I've been involved with:
Other students have already submitted patches that were accepted and applied to projects such as the stdlib logging module.

If you want to witness all this for yourself, and maybe get some help for your project from some really smart students, send an email with your proposal for tasks to the GHOP discussion list.

Modifying EC2 security groups via AWS Lambda functions

One task that comes up again and again is adding, removing or updating source CIDR blocks in various security groups in an EC2 infrastructur...