How to use Gradle Kotlin DSL in Android

include(":app")

import org.gradle.kotlin.dsl.apply
import org.gradle.kotlin.dsl.dependencies
import org.gradle.kotlin.dsl.kotlin
import org.gradle.kotlin.dsl.*
import org.jetbrains.kotlin.config.KotlinCompilerVersion

plugins {
    id("com.android.application")
    kotlin("android")
    kotlin("android.extensions")
}

//apply {
//    from("$rootDir/tools/grgit.gradle")
//    from("$rootDir/buildSrc/quality.gradle.kts")
//    from("$rootDir/tools/ktlint.gradle")
//    from("$rootDir/tools/detekt.gradle")
//}

android {
    compileSdkVersion(28)
    flavorDimensions("default")

    defaultConfig {
        applicationId = "com.onmyway133.myapp"
        minSdkVersion(26)
        targetSdkVersion(28)
//        versionCode = ext.get("gitCommitCount") as? Int
        versionCode = 1
        versionName = "1.0"
        testInstrumentationRunner = "androidx.test.runner.AndroidJUnitRunner"
    }

    signingConfigs {
        create("release") {
            keyAlias = "keyalias"
            keyPassword = "keypassword"
            storePassword = "storepassword"
            storeFile = file("/Users/khoa/Android/Key/keystore")
        }
    }

    buildTypes {
        getByName("debug") {
            signingConfig = signingConfigs.getByName("debug")
            isMinifyEnabled = true
            proguardFiles(getDefaultProguardFile("proguard-android-optimize.txt"), "$project.rootDir/tools/proguard-rules-debug.pro")
        }

        getByName("release") {
            signingConfig = signingConfigs.getByName("release")
            isMinifyEnabled = true
            isShrinkResources = true
            proguardFiles(getDefaultProguardFile("proguard-android-optimize.txt"), "$project.rootDir/tools/proguard-rules.pro")
        }
    }

    productFlavors {
        create("staging") {

        }

        create("production") {

        }
    }

    lintOptions {
        lintConfig = file("$project.rootDir/tools/lint-rules.xml")
        htmlOutput = file("$project.buildDir/outputs/lint/lint.html")
        xmlReport = false
        htmlReport = true
    }
}

dependencies {
    implementation(fileTree(mapOf("dir" to "libs", "include" to listOf("*.jar"))))
    implementation(kotlin("stdlib-jdk7", KotlinCompilerVersion.VERSION))
    implementation("androidx.appcompat:appcompat:1.0.2")
    implementation("androidx.core:core-ktx:1.0.2")
    implementation("androidx.constraintlayout:constraintlayout:1.1.3")
    implementation("com.google.android.material:material:1.0.0")
    testImplementation("junit:junit:4.12")
    androidTestImplementation("androidx.test:runner:1.1.1")
    androidTestImplementation("androidx.test.espresso:espresso-core:3.1.1")
}

tasks.getByName("check").dependsOn("lint")

plugins {
    id("findbugs")
    id("pmd")
    id("checkstyle")
}

tasks {
    val findbugs by registering(FindBugs::class) {
        ignoreFailures = false
        effort = "max"
        reportLevel = "low"
        classes = files("$project.buildDir/intermediates/javac")

        setExcludeFilter(file("$rootProject.rootDir/tools/findbugs-exclude.xml"))

        source = fileTree("src/main/java/")
        classpath = files()

        reports {
            xml.isEnabled = false
            html.isEnabled = true
            html.destination = file("$project.buildDir/outputs/findbugs/findbugs-output.html")
        }
    }

    val pmd by registering(Pmd::class) {
        ruleSetFiles = files("${project.rootDir}/tools/pmd-rules.xml")
        ignoreFailures = false
        ruleSets = listOf<String>()

        fileTree()
        source(fileTree(baseDir = "src/main/java"))
        include("**/*.kt")
        exclude("**/gen/**")

        reports {
            xml.isEnabled = false
            html.isEnabled = true
            html.destination = file("$project.buildDir/outputs/pmd/pmd.html")
        }
    }

    val checkstyle by registering(Checkstyle::class) {
        description = "Check code standard"
        group = "verification"

        configFile = file("$project.rootDir/tools/checkstyle.xml")
        source(fileTree(baseDir = "src"))
        include("**/*.kt")
        exclude("**/gen/**")

        classpath = files()
        ignoreFailures = false
    }
}