CI/CD for Flutter - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to specify the Flutter version in the GitHub Actions workflow.

Flutter

uses: subosito/flutter-action@v1
  with:
    flutter-version: [1]

Drag options to blanks, or click blank then click option'

A2.0.0

B4.0.0

C3.7.0

D1.22.0

Attempts:

3 left

💡 Hint

Common Mistakes

Using an outdated Flutter version that lacks needed features.

Leaving the version blank, causing the workflow to fail.

The flutter-version key sets the Flutter SDK version for the workflow. Using 3.7.0 ensures compatibility with recent Flutter features.

2fill in blank

medium

Complete the code to run Flutter tests in the GitHub Actions workflow.

Flutter

- name: Run Flutter tests
  run: flutter [1]

Drag options to blanks, or click blank then click option'

Adoctor

Bbuild

Canalyze

Dtest

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'flutter build' instead of 'flutter test' to run tests.

Using 'flutter analyze' which only checks code style.

The flutter test command runs unit and widget tests in your Flutter project during CI.

3fill in blank

hard

Fix the error in the workflow step to build an APK for Android.

Flutter

- name: Build APK
  run: flutter [1] apk --release

Drag options to blanks, or click blank then click option'

Abuild

Brun

Cinstall

Ddeploy

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'flutter run apk' which is invalid syntax.

Using 'flutter deploy' which is not a Flutter CLI command.

The correct command to build an APK is flutter build apk --release. 'build' tells Flutter to compile the app.

4fill in blank

hard

Fill both blanks to set up caching for Flutter dependencies in GitHub Actions.

Flutter

- name: Cache Flutter dependencies
  uses: actions/cache@v3
  with:
    path: [1]
    key: ${{ runner.os }}-flutter-${{ hashFiles('[2]') }}

Drag options to blanks, or click blank then click option'

A~/.pub-cache

Bpubspec.lock

Cbuild

Dflutter.lock

Attempts:

3 left

💡 Hint

Common Mistakes

Caching the 'build' folder which is large and changes often.

Using a wrong lock file name like 'flutter.lock'.

Caching ~/.pub-cache speeds up dependency installation. Using pubspec.lock in the key ensures cache updates when dependencies change.

5fill in blank

hard

Fill all three blanks to create a GitHub Actions job that checks out code, sets up Flutter, and runs tests.

Flutter

jobs:
  test:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/[1]@v3
      - uses: subosito/flutter-action@v1
        with:
          flutter-version: [2]
      - name: Run tests
        run: flutter [3]

Drag options to blanks, or click blank then click option'

Acheckout

B3.7.0

Ctest

Dsetup

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'actions/setup' instead of 'actions/checkout'.

Forgetting to specify the Flutter version.

Running 'flutter build' instead of 'flutter test' in the test step.

The actions/checkout action gets the code. Setting flutter-version to 3.7.0 installs Flutter. Running flutter test executes tests.

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