Gradle task to strip unused packages on Google Play Services library, so you don't have to use necessarily Proguard or MultiDex

build.gradle

apply from: 'strip_play_services.gradle'

proguard-rules.txt

-dontwarn com.google.android.gms.**

strip_play_services.gradle

// taken from https://gist.github.com/Takhion/10a37046b9e6d259bb31

def toCamelCase(String string) {
    String result = ""
    string.findAll("[^\\W]+") { String word ->
        result += word.capitalize()
    }
    return result
}

afterEvaluate { project ->
    Configuration runtimeConfiguration = project.configurations.getByName('compile')
    ResolutionResult resolution = runtimeConfiguration.incoming.resolutionResult
    // Forces resolve of configuration
    ModuleVersionIdentifier module = resolution.getAllComponents().find { it.moduleVersion.name.equals("play-services") }.moduleVersion
    String prepareTaskName = "prepare${toCamelCase("${module.group} ${module.name} ${module.version}")}Library"
    Task prepareTask = project.tasks.findByName(prepareTaskName)
    File playServiceRootFolder = prepareTask.explodedDir
    // Add the stripping to the existing task that extracts the AAR containing the original classes.jar
    prepareTask.doLast {
        // First create a copy of the GMS classes.jar
        copy {
            from(file(new File(playServiceRootFolder, "classes.jar")))
            into(file(playServiceRootFolder))
            rename { fileName ->
                fileName = "classes_orig.jar"
            }
        }
        // Then create a new .jar file containing everything from the first one except the stripped packages
        tasks.create(name: "stripPlayServices" + module.version, type: Jar) {
            destinationDir = playServiceRootFolder
            archiveName = "classes.jar"
            from(zipTree(new File(playServiceRootFolder, "classes_orig.jar"))) {
                exclude "com/google/ads/**"
                exclude "com/google/android/gms/actions/**"
                exclude "com/google/android/gms/ads/**"
                exclude "com/google/android/gms/analytics/**"
                exclude "com/google/android/gms/appindexing/**"
                exclude "com/google/android/gms/appstate/**"
                exclude "com/google/android/gms/auth/**"
                exclude "com/google/android/gms/cast/**"
                exclude "com/google/android/gms/drive/**"
                exclude "com/google/android/gms/fitness/**"
                exclude "com/google/android/gms/games/**"
                exclude "com/google/android/gms/gcm/**"
                exclude "com/google/android/gms/identity/**"
                exclude "com/google/android/gms/location/**"
                exclude "com/google/android/gms/maps/**"
                exclude "com/google/android/gms/panorama/**"
                exclude "com/google/android/gms/plus/**"
                exclude "com/google/android/gms/security/**"
                exclude "com/google/android/gms/tagmanager/**"
                exclude "com/google/android/gms/wallet/**"
                exclude "com/google/android/gms/wearable/**"
            }
        }.execute()
        delete file(new File(playServiceRootFolder, "classes_orig.jar"))
    }
}

Hi Takhion, thank you for your script.

I got this error: Error:Cannot get property 'moduleVersion' on null object
on the line "ModuleVersionIdentifier module = resolution.getAllComponents().find { it.moduleVersion.name.equals("play-services") }.moduleVersion"

I'm using google service as library which I imported in Android Studio as a module
Could you help me on this

Same issue here, few years later. Did you find a solution to this? I assumed it refers to project, but replacing doesn't work because property moduleVersion doesn't exist in project.