I am on a Fastlane to Hell

This Lightning Talk is an introduction to Fastlane build automation. It was first held at Droidcon 2017 in London.

Transcript

1. I am on a fastlane to hell Jan Kettner @realitymatters Hi My name is Jan Kettner, I am currently an engineer at Careem in Dubai and I would like to talk to you about Fastlane
2. I cheated Before I begin I have to confess that I cheated. I wanted to have a snappy title, so if you are expecting me to bash fastlane I have to disappoint you. Fastlane is not the road to hell, quite the opposite…
3. what is fastlane and how can it help you? Fastlane is a command line wrapper for a number of scripts that help you automate your build. It allows you to build and deploy your mobile app. It integrates into your team communication or task management systems and you can even record screenshots from your ui tests
4. why should you use it? Now You might ask: Why shouldn’t I just write all those scripts myself? I know gradle? Fastlane is stable, easy to use, it performs well and is easy to extend. But most of all, it is already there! You can spend your time doing sth cool.
5. a little shop release of horror But to make my point more clear I would like to take you on a journey into the past I started my first job in 2011 as an android developer. I was their one man android army. After a couple of month of programming we were able to push our app to market. I loved my job but I dreaded releases one of the reasons was that we had a waterfall process and our QA team only checked the app directly before the release. So when I was done with my tasks, I would push my changes and I would manually start a build on our ci server server. It was still ant and terribly slow. The whole thing took about 15 minutes. when I started the build, it would be the first time that I would build the current state of the app with proguard, sometimes the app would not compile because I messed up proguard config, sometimes the build failed for other reasons and I would have to fix the issue and start over again waiting for next 15 minutes on a friday 8 p.m. When I had the artifact I would im the QA team send them the link to the artifact. They would test for about 30 min and they would always find some defects, some small behaviour that was never specified. remember this is 2011, my first job, no separation of concerns, so no junit tests, and there was no robolectric yet Anyway I would have to fix the issue and start the 15 min build again. send the link of the artifact again and yes I also managed to send the wrong link once or twice. But when I did get the green light I would upload the apk and finally press submit, but … this sometimes also failed because I might have forgotten to update apps versioncode in the Manifest
6. what went wrong This dance could last hours and looking back now i ask myself what i could have improved back then
7. what went wrong never built artifact before release first, I should have tried to create an artifact before releases. Thats like the first rule of continuous delivery, make sure that you can release your master branch at any time
8. what went wrong never built artifact before release app was never tested before release next tests, if I had written and run more tests if the qa team had tested the app more frequently then the number of defects found before release would have been much lower
9. what went wrong never built artifact before release no beta distribution app was never tested before release if had something like hockey or google alpha back then it would have bee much easier to distribute the app to the qa team or to my boss
10. what went wrong never built artifact before release no beta distribution do everything manually app was never tested before release if you noticed I did everything by hand, updating the version code, trigger the release build, send the link to the qa team, this is a bad idea because
11. what went wrong never built artifact before release no beta distribution human error app was never tested before release do everything manually human error, to quote Bill Murray People are stupid, people eat blood sausage, it is normal that sometimes mistakes happen, and this is especially true if you are tired and want to go home
12. fastlane to the rescue so in hindsight i would try to build and run the tests of my app as often as possible and most of all I would try to automate everything, and this is where fastlane comes in
13. so how does fastlane work? In fastlane you create so called lanes in which you perform certain actions, so in my situation I could have created a lane development, that would be triggered after every commit create a release artifact and run all my test. I would create another lane for beta deployment and one more lane to upload the app to google play
14. can you please show how? so how do you use fastlane? actually is very simple
15. can you please show how? ~$ fastlane release in order to start the lane the lane RELEASE, just type fastlane release
16. it can’t be that simple json_key_file "./Google Play Android Developer-************.json” package_name "your.package.name" true, to setup fastlane You would, need to add configuration into a file called APPFILE. There you would specify the package name of your app and the location of your Google credentials
17. can you please show how ? default_platform :android platform :android do end end But the heart of fastlane resides in a file called FAST FILE. Fastlane is written in ruby and uses ruby syntax. In the Fastfile you define the platform of your app and specify the lanes
18. can you please show how ? desc: “This is a description” lane :develop do end a lane simply looks like this, you have a description and an identifier, thats all, now we can add actions
19. can you please show how ? lane :release do gradle(task: "clean assemble test”) end This action will start a list of gradle tasks
20. can you please show how ? lane :release do gradle(task: "clean assembleRelease test android”) supply end In order to upload the app to google play we just add the supply action, now we can call fastlane release from command line or better start it with one click from within your ci so you have a one click deployment
21. what else can I do with fastlane? Fastlane comes with a large number of built in actions for source control, deployment and communication. You can also install plugins, actions created by other fastlane users, Lets look at some examples
22. beta deployment lane :alpha do gradle(task: "clean assemble test connectedAndroidTest”) supply end If you want to upload your app to google alpha
23. beta deployment lane :alpha do gradle(task: "clean assemble test connectedAndroidTest”) supply( track: 'alpha' ) end you would add that information to the supply action, by specifying the track parameter
24. beta deployment lane :alpha do gradle(task: "clean assemble test connectedAndroidTest”) supply( track: ‘rollout’, rollout: 0.1 ) end also integrates crashlytics, hockey, testflight, installr, … you can do the same for beta or staged rollout
25. tell the team about it lane :release do gradle(task: "clean assembleRelease test android”) supply slack({ message: ‘Version1.2 is out’, channel: announcements }) end if you want to send a message with slack for every build there is an action for that
26. tell the world about it lane :release do gradle(task: "clean assembleRelease test android”) supply twitter( message: “We just released Version 0.1.1212. http://awesomeapp.com/download” )' end also integrates hip chat, telegram, mailgun, chatwork, … or you can tweet to notify your users of a new version of your app
27. version code lane :release do gradle(task: "clean assembleRelease test android”) supply increment_version_code end As I mentioned in my example it is really easy to forget to update the android version code
28. jira lane :release do supply release_jira_version create_jira_version end After you uploaded your app you can use fastlane to automatically manage release versions in jira, there is no need to do it manually
29. adb lane :alpha do adb shell iftop -r 50 gradle(task: "connectedAndroidTest”) end there is also an action to access your emulator or attached devices
30. shell scripts lane :print do sh "cat ‘can of food’" end but if you really need to do something very specific, just call your existing shell scripts from fastlane
31. before… before_all do end lane :print do end similar to Junits setup and teardown methods you can define actions that should be run before all lanes, like initialize you slack web hook
32. …and after lane :print do end after_all do |lane| end error do |lane, exception| end remember you will usually run this from your ci so might be a good idea to send a message when a build is complete or it fails
33. you said something about screenshots with fastlane you can upload the metadata for your app, you should not need to manually copy and paste the release notes for all the languages that you localize your app in. When you initialize fastlane it will download the existing store entry and will update it with every supply command including that versions release notes
34. @Test public void Given_unicorns_When_I_click_a_button_Then_magic() { ViewInteraction actionMenuItemView = onView(withId(R.id.view)); actionMenuItemView.perform(click()); Screengrab.screenshot(“screenshot name"); } you said something about screenshots but my favorite features of fastlane is that you can automatically create screenshots of the current state of your app. To take a screenshot you call the screengrab library from your espresso tests and then …
35. lane :release do gradle(task: "clean assemble”) screengrab supply end you said something about screenshots call the screengrab action from fastlane. fastlane will now start your ui tests on a headless emulator and take screenshots at the locations you specified
36. can I write my own actions? as I said, Fastlane comes with a large number of predefined actions and there are hundreds of plugins written by other fastlane users, but if you are still missing that one tool that saves your day, you can write your own plugins
37. can I write my own actions? ~$ fastlane new_action simply type fastlane new_action and fastlane will generate a ruby file for you that contains all of the necessary boilerplate code. And if you think that your action is something that every developer should have, you can submit it, to make your plugin available to other users
38. what about a sample
39. # If you want to automatically update fastlane if a new version is available: update_fastlane fastlane_version "2.61.0" default_platform :android platform :android do before_all do sh("echo no | avdmanager create avd --force -n headless -k \'system-images;android-23;google_apis;x86\'") sh("emulator -avd headless -no-skin -no-audio -no-window > /dev/null 2>&1 &") end desc "New commit on master" lane :develop do skip_docs increment_version_code( gradle_file_path: "app/build.gradle" ) gradle(task: "clean assembleRelease test connectedAndroidTest") commit_android_version_bump(gradle_file_folder:"app") push_to_git_remote end desc "Deploy a new alpha version to Google Play" lane :alpha do supply( track: 'alpha', apk_paths: "app/build/outputs/apk/release/app-release.apk" ) end desc "Release a new version" lane :release do screengrab( clear_previous_screenshots: true, app_apk_path: "app/build/outputs/apk/debug/app-debug.apk", tests_apk_path: "app/build/outputs/apk/androidTest/debug/app-debug-androidTest.apk" ) supply( track: 'production', apk_paths: "app/build/outputs/apk/release/app-release.apk" ) end after_all do |lane| sh("avdmanager delete avd -n headless") end error do |lane, exception| sh("git reset --hard origin/master") end end
40. that’s actually cool how do I get it? as i said in the beginning fastlane is ready to use. In fact one of my iOS colleagues joked about me being invited to droidcon to speak about fastlane because it is so common in the iOS world.
41. that’s actually cool how do I get it? https://fastlane.tools Fastlane makes your job easier. It helps you automate your builds and releases. It is easy to use and comes with a large number of features.
42. thx :) Jan Kettner @realitymatters https://github.com/kaskasi/VocabularyTrainer i would like to thank you for your time, can I answer any questions ?