## Android Setup

### Keystore setup
```bash
keytool -genkey -v -keystore release.keystore -keyalg RSA -keysize 2048 -validity 10000 -alias upload
```
- This is required to store local credentials securely and more importantly to sign the app for google play store distribution.


### Using secret credentials during build
Following the guide under [https://developers.google.com/maps/flutter-package/config#android_1](https://developers.google.com/maps/flutter-package/config#android_1).
- Add the following to `android/build.gradle`:
    ```gradle
    buildscript {
        dependencies {
            classpath "com.google.android.libraries.mapsplatform.secrets-gradle-plugin:secrets-gradle-plugin:2.0.1"
        }
    }
    ```
- Add the following to `android/app/build.gradle`:
    ```gradle
    plugins {
        // ...
        id 'com.google.android.libraries.mapsplatform.secrets-gradle-plugin'
    }
    ```
- Add the credentials to `android/secrets.properties`:
    ```properties
    MAPS_API_KEY=YOUR_API_KEY
    ```
- Reference the credentials in `android/app/src/main/AndroidManifest.xml`:
    ```xml
    <meta-data
        android:name="com.google.android.geo.API_KEY"
        android:value="${MAPS_API_KEY}" />
    ```

### Signing the app
Compared to the flutter template application, a few changes have to be made:
- Added to `android/app/build.gradle`:
    ```gradle
        signingConfigs {
            release {
                keyAlias = secretProperties['keyAlias']
                keyPassword = secretProperties['keyPassword']
                storeFile = secretProperties['storeFile'] ? file(secretProperties['storeFile']) : null
                storePassword = secretProperties['storePassword']
            }
        }
    ```
- Changed the `buildTypes` to use the `release` signing config:
    ```gradle
        buildTypes {
            release {
                signingConfig signingConfigs.release
            }
        }
    ```
    This makes use of the `secretProperties` defined previously:
    ```gradle
        secretPropertiesFile.withReader('UTF-8') { reader ->
            secretProperties.load(reader)
        }
    ```


### Using the credentials in CI
- Add the secret files to the repository secrets (e.g. `ANDROID_SECRETS_PROPERTIES`).

- temporarily write them back to files during the CI execution:
    ```bash
    echo {{ secrets.ANDROID_SECRETS }} >> android/secrets.properties
    ```