Android - Automatic Version Numbering

gistfile1.txt

def getVersionCode = { ->
    try {
        def code = new ByteArrayOutputStream()
        exec {
            commandLine 'git', 'rev-list', 'HEAD', '--count'
            standardOutput = code
        }
        return code.toString().toInteger()
    }
    catch (ignored) {
        return -1;
    }
}

def getVersionName = { ->
    try {
        def stdout = new ByteArrayOutputStream()
        exec {
            commandLine 'git', 'describe', '--tags'
            standardOutput = stdout
        }
        return stdout.toString().trim().split(/-/)[0]
    }
    catch (ignored) {
        return null;
    }
}

android {
    defaultConfig {
        versionCode getVersionCode()
        versionName getVersionName()+'.'+getVersionCode()
    }
}