Continuous Deployment with Capistrano and Jenkins
So we just launched our new site. I figured this was as good a time as any to finally get our ducks in a row vis-a-vis continous deployment. Since this is the sort of thing that a lot of people have to deal with, I figured I'd publish a blog post explaining how we took care of it.
isotope|eleven uses Jenkins for our continous integration server. We have it configured to run the relevant tests anytime a commit is pushed to our git repositories, as well as once daily for each job. We keep the Jenkins Wallboard running on our main conference room TV at all times, so we can see at a glance if any builds are failing. These are all fairly standard practices.
Jenkins is pretty flexible, and so when it came time to do continous deployment I decided to use Jenkins to handle it. In Jenkins, it's very easy to make a job that just executes some shell script (in fact, most of our jobs are precisely this sort). This is perfect, because of course we just have a shell script we use to deploy our projects - capistrano!
Setting up the deploy job
To get started, I built a new job in Jenkins. The repository our site lives
in is called isotope-rails3, as is the main CI job for our site, so the new
job is called isotope-rails3-deploy. I set its git repository URL to our
repo. I then added a single build step, an "Execute Shell" step whose
Finally, I set it to notify me in the event of a failure.
Setting up deploy without intervention
At this point, I can click the 'Build Now' button to kick off the deploy, but it's going to complain about passwords. I also had to set up the jenkins user on the jenkins server to be able to deploy our site passwordless. If you don't know how to do this, this is a pretty good tutorial on setting up your SSH authorized keys.
So now the button works and it will deploy without intervention, but I want to kick off this job after a successful run of our tests so that it will deploy each time we push new code to the deploy branch. To manage this, I just went into our main CI job for the repo and set it to 'Build other projects' in the Post-build Actions, and I told it to build the 'isotope-rails3-deploy' job only if the build succeeded.
Done! Get your Continous Deploy on.
With those simple steps, you've got a robust Continuous Deployment server that can be modified in a host of useful ways, as it's just a standard Jenkins job. Let me know if you try this and have any problems. Thanks!