Continuous Integration With GitHub, Fastlane & Jenkins

Using fastlane With Travis

In fact, you can make your CI life just that bit easier by using fastlane. You may know it as a super-assistant for streamlining deployment to the App Store, but it can also help with CI, by automating unit testing with fastlane scan.

And because Travis CI is so accommodating, you don’t even have to install fastlane on your Mac.

Open .travis.yml to edit it, and replace the last four lines with this:

script:
- fastlane scan

That’s right — you just have to specify the Xcode version and the Swift language, then fastlane takes care of the rest!

Now edit the code in Converter.swift, to make your unit test pass. The starter project has a convert(_:) method that returns an empty String. Change it so it returns "I":

return "I"

Commit and push to GitHub. On your Travis CI Numero repository page, click Build History, then #2 — its status might be received, booting or started.

This time, Travis CI boots a virtual machine (VM):

And the Job log shows the configuration of the VM with Swift, macOS 10.14.4, and various utilities. Travis CI then runs fastlane, which runs an xcodebuild command:

$ fastlane scan
...
$ xcodebuild -showBuildSettings -scheme Numero -project ./Numero.xcodeproj

Cool — fastlane figures out for itself the scheme and project values that you wrote in your first .travis.yml file! Then fastlane finds a simulator — it’s just the first in the simulator list, the 5s. And fastlane defaults to the latest iOS:

Found simulator "iPhone 5s (12.2)"

Then fastlane displays a long Summary for scan table, and eventually displays Test Results:

+--------------------+---+
|      Test Results      |
+--------------------+---+
| Number of tests    | 1 |
| Number of failures | 0 |
+--------------------+---+
...
The command "fastlane scan" exited with 0.
Done. Your build exited with 0.

This time, the build succeeds! But you knew that would happen ;]. And here’s the good news in your mailbox:

Time for a celebration!

Doing CI With Jenkins

Travis CI is such an instant feel-good experience, why would you look anywhere else? Well, maybe because you need CI for a private repository — check out Travis CI Plans & Pricing. Or, if your team or company already maintains or rents servers, it might be more cost-effective to install Jenkins.

Installing Jenkins

Jenkins Docker images exist, but Jenkins running in a Docker container won’t be able to run xcodebuild, so you’ll install Jenkins directly on your Mac. Download the installer by visiting the Jenkins download page and clicking Mac OS X.

While the installer downloads, check to see if you have the appropriate Java installed. You need Java 1.8 to install Jenkins. Mojave doesn’t have Java pre-installed, but if you’re not sure, enter this command to see if you already have it:

java -version

If the output doesn’t include java version “1.8 …”, you’ll need to install it. While you can download it from the Oracle web site, it’s simpler to install it using Homebrew, a popular package manager for macOS. If you don’t have Homebrew installed already, enter this command in Terminal:

/usr/bin/ruby -e \
  "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"

Enter your password if prompted. You should see Installation Successful once it completes.

To install Java, enter this command in Terminal:

brew cask install homebrew/cask-versions/java8

Again, enter your password if prompted.

Once Java 1.8 is installed, run the Jenkins installer, which should have finished downloading by now. When the installer finishes, it should open localhost:8080 in your browser — it wants a password:

The easiest way to find the initial admin password is to look in the log — enter this command:

cat /var/log/jenkins/jenkins.log

There’s a lot in this log, but you only need to scroll up a little from the bottom to see your password between the two triple-rows of asterisks:

*************************************************************
*************************************************************
*************************************************************

Jenkins initial setup is required. An admin user has been created and a password generated.
Please use the following password to proceed to installation:

<your initial admin password>

This may also be found at: /Users/Shared/Jenkins/Home/secrets/initialAdminPassword

*************************************************************
*************************************************************
*************************************************************

Copy the password and paste it into the Administrator password field. Click Continue to load the Customize Jenkins page:

This opens the offending configuration file in a simple text editor. Find https and change it to http. To exit the editor and save the file, press Control-C, then press Y, then finally press Enter. Now, refresh the page in your browser and you should see the correct page.

sudo nano /Users/Shared/Jenkins/Home/hudson.model.UpdateCenter.xml

sudo nano /Users/Shared/Jenkins/Home/hudson.model.UpdateCenter.xml

Select Install suggested plugins, then go for a walk — this takes several minutes.

Ah, you’re back! Now create your admin account — entering admin for both Username and Password works OK:

On the Instance Configuration page, just click Not now:

And on the next page, click Start using Jenkins: