release-signing.gradle

/**
 * Signs release build with the specified signature parameters. When parameters are omitted the
 * release APK file will be left unsigned.
 *
 * By default, keystore.properties file in the project's or root project's folder will be used as a
 * source of required signing data:
 *
 *     storeFile=/Users/me/keyvault/release.keystore
 *     storePassword=pass123
 *     keyAlias=sampleAlias
 *     keyPassword=pass123
 *
 * Otherwise you can use this optional command line parameters:
 *
 *     keystorePropertiesFile - path to your properties file with "storeFile", "storePassword",
 *     "keyAlias", "keyPassword" properties
 *
 *     storeFile - path to your keystore file
 *
 *     storePassword, keyAlias, keyPassword - all other signature data for the specified keystore
 *
 * Examples:
 *
 *     gradlew assembleRelease -PstoreFile=/Users/me/keyvault/release.keystore
 *     -PstorePassword=pass123 -PkeyAlias=sampleAlias -PkeyPassword=pass123
 *
 *     gradlew assembleRelease -PkeystorePropertiesFile=/Users/me/keyvault/keystore.properties
 *
 * It is ok to specify partial data in properties file and all the other data with command line
 * parameters:
 *
 *     gradlew assembleRelease -PkeystorePropertiesFile=/Users/me/keyvault/keystore.properties
 *     -PstorePassword=pass123 -PkeyPassword=pass123
 */

final String KEYSTORE_PROPERTIES_FILENAME = "keystore.properties"
String inputStoreFile, inputStorePassword, inputKeyAlias, inputKeyPassword

// try to read signing data from local or custom keystore.properties
File keystorePropertiesFile
if (project.hasProperty('keystorePropertiesFile') && project.keystorePropertiesFile) {
    keystorePropertiesFile = file(project.keystorePropertiesFile)
} else {
    File[] keystorePropertiesLocations = [
            project.file(KEYSTORE_PROPERTIES_FILENAME),
            project.rootProject.file(KEYSTORE_PROPERTIES_FILENAME)
    ]
    keystorePropertiesFile = keystorePropertiesLocations.find { it.exists() }
}
if (keystorePropertiesFile?.exists()) {
    Properties keystoreProperties = new Properties()
    keystoreProperties.load(keystorePropertiesFile.newReader())
    inputStoreFile = keystoreProperties.getProperty('storeFile')
    inputStorePassword = keystoreProperties.getProperty('storePassword')
    inputKeyAlias = keystoreProperties.getProperty('keyAlias')
    inputKeyPassword = keystoreProperties.getProperty('keyPassword')
}

// then try to read all command line parameters
if (project.hasProperty('storeFile') && project.storeFile) {
    inputStoreFile = project.storeFile
}
if (project.hasProperty('storePassword') && project.storePassword) {
    inputStorePassword = project.storePassword
}
if (project.hasProperty('keyAlias') && project.keyAlias) {
    inputKeyAlias = project.keyAlias
}
if (project.hasProperty('keyPassword') && project.keyPassword) {
    inputKeyPassword = project.keyPassword
}

// if all needed info is supplied then generate signing config
if (inputStoreFile && inputStorePassword && inputKeyAlias && inputKeyPassword) {
    android {
        signingConfigs {
            release {
                storeFile file(inputStoreFile)
                storePassword inputStorePassword
                keyAlias inputKeyAlias
                keyPassword inputKeyPassword
            }
        }
    }
    android.buildTypes["release"].signingConfig = android.signingConfigs.release
    println "Release configuration generated. Release APK will be SIGNED."
} else {
    println "Release configuration omitted. Release APK will be left UNSIGNED."
}