version.gradle

/*
 * Initializes versionName and versionCode from version.properties file.
 *
 * Just create version.properties file in the project's or root project's folder with the next
 * properties:
 *
 *     major=1
 *     minor=2
 *     patch=3
 *
 * Optional command line parameters:
 *
 *     versionMetadata - metadata that will be added at the end of versionName
 *
 * Example:
 *
 *     gradlew assembleDebug -PversionMetadata=0df74f19
 */

final String VERSION_PROPERTIES_FILENAME = "version.properties"
final int MAX_MINOR_DIGITS = 2
final int MAX_PATCH_DIGITS = 2

static int readIntegerProperty(Properties properties, String key) {
    String value = properties.get(key)
    if (!value) {
        throw new GradleException("Cannot read '${key}' property")
    }
    if (!value.isInteger()) {
        throw new GradleException("'${key}' property is not integer")
    }
    return value.toInteger()
}

File[] versionPropertiesLocations = [
        project.file(VERSION_PROPERTIES_FILENAME),
        project.rootProject.file(VERSION_PROPERTIES_FILENAME)
]

File versionPropertiesFile = versionPropertiesLocations.find { it.exists() }
if (!versionPropertiesFile) {
    throw new GradleException("Cannot find ${VERSION_PROPERTIES_FILENAME} file")
}

Properties versionProperties = new Properties()
versionProperties.load(versionPropertiesFile.newReader())

int major = readIntegerProperty(versionProperties, 'major')
int minor = readIntegerProperty(versionProperties, 'minor')
int patch = readIntegerProperty(versionProperties, 'patch')

if (minor >= 10**MAX_MINOR_DIGITS) {
    throw new GradleException("Minor version cannot contain more than ${MAX_MINOR_DIGITS} digits." +
            " Current minor version is ${minor}.")
}

if (patch >= 10**MAX_PATCH_DIGITS) {
    throw new GradleException("Patch version cannot contain more than ${MAX_PATCH_DIGITS} digits." +
            " Current patch version is ${patch}.")
}

int versionCode = (major * 10**MAX_MINOR_DIGITS + minor) * 10**MAX_PATCH_DIGITS + patch

String versionName = "${major}.${minor}.${patch}"
if (project.hasProperty('versionMetadata') && project.versionMetadata) {
    versionName = "${versionName}+${project.versionMetadata}"
}

android.defaultConfig.versionName = versionName
android.defaultConfig.versionCode = versionCode

println "versionName " + android.defaultConfig.versionName
println "versionCode " + android.defaultConfig.versionCode