CI/CD for Flutter - Cheat Sheet & Quick Revision

Recall & Review

beginner

What does CI/CD stand for in software development?

CI/CD stands for Continuous Integration and Continuous Delivery (or Continuous Deployment). It means automatically building, testing, and delivering apps to users.

beginner

Why is CI/CD important for Flutter app development?

CI/CD helps Flutter developers catch errors early, automate testing, and deliver app updates faster and more reliably to users.

beginner

Name a popular CI/CD tool that can be used with Flutter projects.

GitHub Actions is a popular tool that can automate Flutter app builds, tests, and deployments.

intermediate

What is a typical first step in setting up CI for a Flutter app?

The first step is to create a workflow file that runs Flutter commands like 'flutter pub get' and 'flutter test' automatically on code changes.

intermediate

How does Continuous Delivery differ from Continuous Deployment in Flutter CI/CD?

Continuous Delivery means the app is ready to release after automated steps, but a person decides when to publish. Continuous Deployment means the app is automatically published after passing tests.

Which command is used to run Flutter tests in a CI pipeline?

A flutter pub get

B flutter build apk

C flutter clean

D flutter test

The 'flutter test' command runs automated tests in Flutter projects.

What file is commonly used to define CI workflows in GitHub Actions for Flutter?

A flutter.yml

B .github/workflows/flutter.yml

C ci.yml

D main.yaml

GitHub Actions workflows are stored in the '.github/workflows/' directory.

Which step is NOT typically part of a Flutter CI pipeline?

A Running unit tests

B Building the app

C Deploying to production without tests

D Fetching dependencies

Deploying without tests is unsafe and not recommended in CI pipelines.

What does 'flutter pub get' do in a CI workflow?

A Fetches app dependencies

B Cleans the project

C Builds the app

D Runs tests

'flutter pub get' downloads the packages your app needs.

In CI/CD, what is the main benefit of automating Flutter app builds?

A Faster and consistent app delivery

B Slower development

C Manual error checking

D Ignoring test results

Automation speeds up delivery and reduces human errors.

Explain the basic steps to set up a CI pipeline for a Flutter app using GitHub Actions.

Think about commands to fetch packages, test, and build.

Describe the difference between Continuous Integration, Continuous Delivery, and Continuous Deployment in Flutter development.

Focus on automation levels and release steps.

Practice

1. What is the main purpose of using CI/CD in Flutter app development?

easy

A. To automate building, testing, and deploying the app

B. To write Flutter code faster manually

C. To design app UI without coding

D. To run the app only on physical devices

Solution

1. Step 1: Understand CI/CD basics

   CI/CD stands for Continuous Integration and Continuous Delivery, which automates building and testing.

2. Step 2: Apply to Flutter context

   In Flutter, CI/CD runs commands like flutter pub get, flutter test, and flutter build automatically.

3. Final Answer:

   To automate building, testing, and deploying the app -> Option A

4. Quick Check:

   CI/CD automates app build and test = A [OK]

Hint: CI/CD means automate build and test steps [OK]

Common Mistakes:

• Thinking CI/CD is manual coding
• Confusing UI design with CI/CD
• Believing CI/CD only runs on devices

2. Which of the following is the correct command to run Flutter tests in a CI workflow?

easy

A. flutter test

B. flutter pub get

C. flutter build apk

D. flutter run

Solution

1. Step 1: Identify test command in Flutter

   The command to run tests in Flutter is flutter test.

2. Step 2: Differentiate from other commands

   flutter build apk builds the app, flutter pub get fetches packages, and flutter run runs the app on a device.

3. Final Answer:

   flutter test -> Option A

4. Quick Check:

   Run tests = flutter test = A [OK]

Hint: Tests run with 'flutter test' command [OK]

Common Mistakes:

• Using 'flutter build apk' to run tests
• Confusing 'flutter pub get' with testing
• Trying to run tests with 'flutter run'

3. Given this GitHub Actions snippet for Flutter CI:

steps:
  - uses: actions/checkout@v3
  - name: Install Flutter
    uses: subosito/flutter-action@v2
  - name: Get dependencies
    run: flutter pub get
  - name: Run tests
    run: flutter test
  - name: Build APK
    run: flutter build apk --release

What will happen if tests fail?

medium

A. The workflow retries tests automatically

B. APK is built regardless of test results

C. The workflow stops and APK is not built

D. Tests are skipped and APK is built

Solution

1. Step 1: Understand GitHub Actions default behavior

   If a command like flutter test fails, the workflow stops by default.

2. Step 2: Apply to given steps

   Since tests run before build, failure stops the workflow and APK build does not run.

3. Final Answer:

   The workflow stops and APK is not built -> Option C

4. Quick Check:

   Test failure stops workflow = D [OK]

Hint: Failed test stops workflow before build [OK]

Common Mistakes:

• Assuming APK builds even if tests fail
• Thinking tests are skipped automatically
• Believing workflow retries tests

4. You wrote this GitHub Actions step to build your Flutter app:

- name: Build APK
  run: flutter build apk --release
  shell: bash

But the build fails with "flutter: command not found". What is the likely cause?

medium

A. The shell should be powershell, not bash

B. The build command syntax is incorrect

C. The APK build requires emulator running

D. Flutter SDK is not installed or not added to PATH

Solution

1. Step 1: Analyze error message

   "flutter: command not found" means the system cannot find the Flutter tool.

2. Step 2: Identify missing setup

   This usually happens if Flutter SDK is not installed or its path is not set in the environment before running the build.

3. Final Answer:

   Flutter SDK is not installed or not added to PATH -> Option D

4. Quick Check:

   Command not found = missing Flutter setup = C [OK]

Hint: Ensure Flutter SDK is installed and in PATH before build [OK]

Common Mistakes:

• Blaming command syntax for 'command not found'
• Thinking shell type causes missing command
• Assuming emulator is needed for build

5. You want to speed up your Flutter CI workflow by caching dependencies. Which step should you add before flutter pub get to cache packages in GitHub Actions?

hard

A. Run flutter clean before flutter pub get

B. Use actions/cache@v3 with path ~/.pub-cache and key based on pubspec.yaml

C. Add flutter build apk before flutter pub get

D. Use actions/upload-artifact@v3 to upload pubspec.yaml

Solution

1. Step 1: Understand caching in GitHub Actions

   actions/cache@v3 caches files between workflow runs to speed up repeated steps.

2. Step 2: Apply caching to Flutter dependencies

   Flutter packages are stored in ~/.pub-cache; caching this folder keyed by pubspec.yaml hash speeds up flutter pub get.

3. Final Answer:

   Use actions/cache@v3 with path ~/.pub-cache and key based on pubspec.yaml -> Option B

4. Quick Check:

   Cache ~/.pub-cache with actions/cache = B [OK]

Hint: Cache ~/.pub-cache keyed by pubspec.yaml for faster builds [OK]

Common Mistakes:

• Running flutter clean which clears cache
• Building APK before fetching dependencies
• Uploading pubspec.yaml as artifact instead of caching