After reading Continuous Deployment for iOS Apps I decided to setup a Jenkins continuous integration server of my own, and to configure it to build my tiny little iOS projects. Rather than use a script to trigger the build I used the XCode plugin for Jenkins to manage the build. In addition to the Xcode plugin I’m using the Git plugin so I can build from Github.
Here are the steps I took to get this working.
##Install Jenkins
Homebrew is my preferred package installation tool and since there is a Jenkins formula for brew I used it to install the server.
$ brew install jenkins
##Start Jenkins
$ java -jar /usr/local/Cellar/jenkins/1.447/lib/jenkins.jar
##Add plugins
By default Jenkins is configured to run at localhost:8080. Open Jenkins in your browser and click on the Manage Jenkins link on the Jenkins dashboard. On the Manage Jenkins page that is returned click on the Manage Plugins link. On the Plugins Manager page, select the Available tab. Scroll down the list and select the Git and Xcode plugins. Click Install without Restart. Once Jenkins restarts you are ready to proceed.
##Specify Location of Xcode
With the release of Xcode 4.3 Apple has changed the location of Xcode. Previously it was in /Developer. Now it appears as an application in /Applications. I ran the xcode-select command to specify the new location of the executables.
$ sudo xcode-select -switch /Applications/Xcode.app/Contents/Developer
You can verify your configuration (if you are using Xcode 4.3) like so:
$ xcode-select -print-path && xcodebuild -version
/Applications/Xcode.app/Contents/Developer
Xcode 4.3
Build version 4E109
$
##Create a new Jenkins project
I created a “freestyle” project for my build and named the build after my project. Under the Source Code Management section I selected Git, and I filled in the path using my Github repository URL. This is the same URL you would use when cloning the project from the command line.
Under Build Triggers I added two conditions. I set a periodic build to occur once a day, at 12:05 pm. Build periodically uses crontab style notation, so the configuration looks like
05 12 * * *
I also selected Build when a change is pushed to Github. Giving the nature of my development process (evenings and weekends) this is probably the more reasonable long term choice.
I selected Xcode for the add build step drop down. This entry is available after adding the XCode plugin. I checked the Clean before build? option, and left all other options alone. My first builds failed as I don’t have a paid Apple Developer membership and the signing certificate that comes with that membership. By default the Xcode plugin tries to build your application for a device, and that requires a signing certificate. By adding the following path to the SDK setting I was able to specify the Simulator SDK for my build.
/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator5.0.sdk/
With the Simulator SDK specified by build succeeds.
##Future Benefits
Having a CI server setup and running for the student level exercises I am currently completing might seem like overkill. But I like the level of maturity having this process in place brings. At a glance now I can see which projects are building and which are broken. Once I have more developed applications that make use of unit testing, having a CI server and process in place will really start to pay off.