KMP Android Build Action

Overview

A comprehensive GitHub Action for building Android applications with support for multiple flavors, build types, and secure release configurations.

Features

• 🤖 Cross-flavor Android app building
• 🔒 Secure release configuration support
• 📦 Automatic artifact generation
• 🚀 Version code generation
• 🔑 Keystore and Google Services integration

Usage Examples

Debug Build

- name: Checkout Repository
  uses: actions/checkout@v4
  with:
    fetch-depth: 0

- name: Build Android Debug
  uses: openMF/[email protected]
  with:
    android_package_name: 'myapp'

Release Build

- name: Build Android Release
  uses: openMF/[email protected]
  id: build-android
  with:
    android_package_name: 'myapp'
    build_type: 'Release'
    key_store: ${{ secrets.KEYSTORE_BASE64 }}
    google_services: ${{ secrets.GOOGLE_SERVICES_BASE64 }}
    key_store_password: ${{ secrets.KEYSTORE_PASSWORD }}
    key_store_alias: ${{ secrets.KEY_ALIAS }}
    key_store_alias_password: ${{ secrets.KEY_ALIAS_PASSWORD }}

- name: Display APK Paths
  run: |
    echo "Demo APK: ${{ steps.build-android.outputs.demo_apk }}"
    echo "Prod APK: ${{ steps.build-android.outputs.prod_apk }}"

Workflow Diagram

flowchart TD
    A[Start Build Process] --> B[Set up Java 17]
    B --> C[Setup Gradle]
    C --> D[Cache Gradle Dependencies]
    D --> E[Generate Version Number]
    E --> F{Build Type?}
    F -->|Debug| G[Build Debug APK]
    F -->|Release| H[Inflate Secrets]
    H --> I[Build Release APK]
    G --> J[Collect APK Paths]
    I --> J
    J --> K[Upload Artifacts]
    K --> L[End Build Process]

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Android Project Configuration

Release Build Environment Variables To use release build environment variables in your Android project, update your build.gradle files:

App-level build.gradle

android {
    namespace = "org.mifospay"

    defaultConfig {
        applicationId = "org.mifospay"
        versionName = System.getenv("VERSION") ?: project.dynamicVersion
        versionCode = System.getenv("VERSION_CODE")?.toIntOrNull() ?: 1
        vectorDrawables.useSupportLibrary = true
        testInstrumentationRunner = "androidx.test.runner.AndroidJUnitRunner"
    }

    signingConfigs {
        create("release") {
            storeFile = file(System.getenv("KEYSTORE_PATH") ?: "release_keystore.keystore")
            storePassword = System.getenv("KEYSTORE_PASSWORD") ?: "DefaultPassword"
            keyAlias = System.getenv("KEYSTORE_ALIAS") ?: "default-alias"
            keyPassword = System.getenv("KEYSTORE_ALIAS_PASSWORD") ?: "DefaultAlias"
            enableV1Signing = true
            enableV2Signing = true
        }
    }
}

Inputs

android_package_name

• Description: Name of the Android project module
• Required: true
• Type: string
• Example: 'app'

build_type

• Description: Type of build to perform
• Required: true
• Default: 'Debug'
• Options:
  • 'Debug'
  • 'Release'

key_store (Optional for Release)

• Description: Base64 encoded keystore file
• Required: false (Required for Release builds)
• Type: string

google_services (Optional)

• Description: google-services.json file
• Required: false
• Type: string

Additional Security Inputs

• key_store_password
• key_store_alias
• key_store_alias_password

Outputs

artifact-name

• Description: Generated artifact name
• Type: string
• Default: 'android-app'

Release Configuration

For release builds, you must provide:

• Base64 encoded keystore
• Keystore password
• Keystore alias
• Keystore alias password

Version Generation

1. Gradle versionFile Task (Preferred)

• If version.txt can be generated via Gradle task
• Version read from version.txt
• Version code calculated based on total commit count

2. Git-based Fallback

• Uses latest Git tag
• Starts from 1.0.0 if no tags exist
• Increments patch version
• Generates version code based on commit count

Artifact Handling

• Uploads APKs for both Demo and Prod flavors
• Artifact name defaults to android-app
• APK paths are dynamically discovered

Best Practices

• Use secrets for sensitive information
• Separate debug and release configurations
• Implement secure keystore management
• Use mock files for development

Troubleshooting

• Verify keystore and Google Services configurations
• Check Gradle build scripts
• Review GitHub Actions logs
• Ensure all required secrets are configured

Performance Optimization

• Gradle dependency caching
• Efficient version code generation
• Minimal build step overhead

Security Considerations

• Never commit sensitive files directly
• Use GitHub secrets for confidential data
• Rotate keys and credentials regularly

Requirements

• Java 17
• Gradle
• Android Gradle Plugin
• Configured flavors (Demo/Prod)