Continuous Integration

I finally got around to setting up Jenkins for some continuous integration on one of the projects I contribute to at work. It’s been a long time coming and we’ve been talking about it for awhile. Finally getting it done ended up taking longer than expected. No surprise there, with the constant pressure to deliver and release, we often forget that quality and quality assurance are an important aspect of shipping. If you deliver something that’s broken, then you’re not really delivering at all.

The main thing we wanted to get from Jenkins was the ability to fire off our unit tests in an integration environment on each git push. We managed to do this with a server side git hook, which curls Jenkins after each successful push to the git repository. What I didn’t realize at the time was that Jenkins can do so much more than just run your unit tests for you. After playing with it for the better part of a week, I now have a build script that executes our unit tests, builds class docs, runs static analysis, lints the code, and ensures that we are conforming to our teams coding standards.

In the future I’d like to also see if we can’t leverage Jenkins to push our code out to staging + production after a successful build.

There are a few things that surprised me about myself after my week with Jenkins. Perhaps the most surprising thing for me was how much a little dot can influence my state of mind. Red is bad, and green is good, and if you turn my happy place red, I will hunt you down (just kidding, mostly).

It’s nice when the unit tests are passing, even though it obviously doesn’t mean that the system is bug free, or that our unit tests are perfect, or that we have anywhere near the code coverage we’d like. The static analysis gives us our mess detection score, our levels of copy pasted code, and our CRAP score. What’s more, we can track how those values change over time to see if we’re improving or not.

I know I’ve only just touched the tip of the iceberg with regards to what Jenkins can do for me, if you have suggestions for further investigation, drop me a line.