How to consolidate imported plugins to custom plugin in Gradle using Kotlin

Question

I have microservices that will share some of the same configuration between all of them, mainly Jib, publish, and release. Not sure if it's possible to do the same for dependencies but it would be beneficial to include actuator and log4j2 in each. Here is the build.gradle.kts for one of my projects.

import net.researchgate.release.BaseScmAdapter
import net.researchgate.release.GitAdapter
import net.researchgate.release.ReleaseExtension
import org.jetbrains.kotlin.gradle.tasks.KotlinCompile

plugins {
    id("com.gorylenko.gradle-git-properties") version "1.5.1"
    id("com.google.cloud.tools.jib") version "1.6.1"
    id("io.spring.dependency-management") version "1.0.7.RELEASE"
    id("net.researchgate.release") version "2.8.1"
    id("org.sonarqube") version "2.7.1"
    id("org.springframework.boot") version "2.1.6.RELEASE"
    kotlin("jvm") version "1.2.71"
    kotlin("plugin.spring") version "1.2.71"
    jacoco
    `maven-publish`
}

java.sourceCompatibility = JavaVersion.VERSION_1_8

springBoot {
    buildInfo {
        group = project.properties["group"].toString()
        version = project.properties["version"].toString()
        description = project.properties["description"].toString()
    }
}

repositories {
    maven(url = uri(project.properties["nexus.url.gateway"].toString()))
    mavenCentral()
}

dependencies {
    // Kotlin
    implementation("org.jetbrains.kotlin:kotlin-reflect")
    implementation("org.jetbrains.kotlin:kotlin-stdlib-jdk8")

    // Spring
    implementation("org.springframework.boot:spring-boot-starter-actuator")
    implementation("org.springframework.boot:spring-boot-starter-log4j2")
    implementation("org.springframework.boot:spring-boot-starter-security")
    implementation("org.springframework.cloud:spring-cloud-config-server")
    testImplementation("org.springframework.boot:spring-boot-starter-test")
}

dependencyManagement {
    imports {
        mavenBom("org.springframework.cloud:spring-cloud-dependencies:Greenwich.SR3")
    }
}

configurations.all {
    exclude(group = "ch.qos.logback", module = "logback-classic")
    exclude(group = "org.springframework.boot", module = "spring-boot-starter-logging")
}

tasks {
    withType<KotlinCompile> {
        kotlinOptions {
            freeCompilerArgs = listOf("-Xjsr305=strict")
            jvmTarget = "1.8"
        }
    }

    build { dependsOn(clean) }
    afterReleaseBuild { dependsOn(publish) }
    publish { dependsOn(build) }
    jibDockerBuild { dependsOn(build) }
    jacocoTestReport {
        reports {
            html.isEnabled = false
            xml.isEnabled = true
        }
    }
}

publishing {
    publications {
        create<MavenPublication>(project.name) {
            from(components["java"])
            pom {
                scm {
                    connection.set("scm:git:git@github.com:company/${project.name}.git")
                    developerConnection.set("scm:git:git@github.com:company/${project.name}.git")
                    url.set("https://github.com/company/${project.name}/")
                }
            }
            versionMapping {
                usage("java-api") {
                    fromResolutionOf("runtimeClasspath")
                }
                usage("java-runtime") {
                    fromResolutionResult()
                }
            }
        }
    }
    repositories {
        maven {
            val releasesRepoUrl = "${project.properties["nexus.url.publish"].toString()}/releases"
            val snapshotsRepoUrl = "${project.properties["nexus.url.publish"].toString()}/snapshots"
            url = uri(if (version.toString().endsWith("SNAPSHOT")) snapshotsRepoUrl else releasesRepoUrl)
            credentials {
                username = project.properties["nexus.user"].toString()
                password = project.properties["nexus.password"].toString()
            }
        }
    }
}

fun ReleaseExtension.git(configureFn : GitAdapter.GitConfig.() -> Unit) {
    (propertyMissing("git") as GitAdapter.GitConfig).configureFn()
}

release {
    scmAdapters = mutableListOf<Class<out BaseScmAdapter>> ( GitAdapter::class.java )

    git {
        requireBranch = "develop"
        pushToRemote = project.properties["release.git.remote"].toString()
        pushReleaseVersionBranch = "master"
        tagTemplate = "${project.name}.${project.version}"
    }
}

jib {
    from {
        image = "openjdk:8-jdk-alpine"
    }
    to {
        image = "host:port/${project.name}:${project.version}"
        auth {
            username = project.properties["nexus.user"].toString()
            password = project.properties["nexus.password"].toString()
        }
    }
    container {
        workingDirectory = "/"
        ports = listOf("8080")
        environment = mapOf(
                "SPRING_OUTPUT_ANSI_ENABLED" to "ALWAYS",
                "SPRING_CLOUD_BOOTSTRAP_LOCATION" to "/path/to/bootstrap.yml"
        )
        useCurrentTimestamp = true
    }
    setAllowInsecureRegistries(true)
}

I was able to get a custom plugin created and added to this project using git@github.com:klg71/kotlintestplugin.git and git@github.com:klg71/kotlintestpluginproject.git but I have no idea how to implement these existing plugins and their configurations. In the main Plugin class in the apply function I am able to call the project.pluginManager.apply(PublishingPlugin::class.java) which causes the task to show in the project referencing the custom plugin but I can't figure out how to configure it and it does not successfully publish to the nexus server. I can publish the plugin itself to the nexus server and reference it in the microservice but it skips running the task, which I assume is caused by the configuration not being included. Also, when trying to apply/configure the Jib plugin, all of the classes are not visible when attempting to import.

Answer 1

So the above answer isn't super long and to preserve the issues I ran into I am posting a new answer.

PLUGIN

This portion of the answer is going to discuss the actual custom plugin project. Because the plugins wrapper in the build.gradle.kts is runtime, the CustomPlugin.kt does not have access to it at compile time. My boss who is much smarter than me was kind enough to point this out to me even though he has never worked with gradle. Although I looked pretty dumb in front of him he still got me up and running by basically following the 'legacy' way of applying plugins in gradle.

plugins { // This is a runtime script preventing plugins declared here to be accessible in CustomPlugin.kt but is used to actually publish/release this plugin itself
    id("net.researchgate.release") version "2.8.1"
    kotlin("jvm") version "1.3.0"
    `maven-publish`
}

repositories {
    maven { url = uri("https://plugins.gradle.org/m2/") } // This is required to be able to import plugins below in the dependencies
    jcenter()
}

dependencies {
    compile(kotlin("stdlib"))
    compile(kotlin("reflect"))

    // These must be declared here (at compile-time) in order to access in CustomPlugin.kt
    compile(group = "gradle.plugin.com.gorylenko.gradle-git-properties", name = "gradle-git-properties", version = "2.2.0")
    compile(group = "gradle.plugin.com.google.cloud.tools", name = "jib-gradle-plugin", version = "1.7.0")
    compile(group = "net.researchgate", name = "gradle-release", version = "2.8.1")
    compile(group = "org.asciidoctor", name = "asciidoctor-gradle-plugin", version = "1.5.9.2")
    compile(group = "org.jetbrains.dokka", name = "dokka-gradle-plugin", version = "0.9.18")
    compile(group = "org.sonarsource.scanner.gradle", name = "sonarqube-gradle-plugin", version = "2.8")

    implementation(gradleApi()) // This exposes the gradle API to CustomPlugin.kt
}

This allowed me to have access to jib and everything else in the CustomPlugin.kt. The plugins jacoco and maven-publish are automatically accessible in the plugin project but still need to be added in the microservice project referencing the plugin. I was unable to find a workaround for this unfortunately.

I included the typical maven-publish plugin in the build.gradle.kts to push to nexus with the publishing task configurations in the build.gradle.kts as well so I could pull this from nexus in the microservice that wanted to use the plugin.

publishing {
    publications {
        create<MavenPublication>(project.name) {
            from(components["java"])
            pom {
                scm {
                    connection.set("scm:git:git@github.com:diendanyoi54/${project.name}.git")
                    developerConnection .set("scm:git:git@github.com:diendanyoi54/${project.name}.git")
                    url.set("https://github.com/diendanyoi54/${project.name}/")
                }
            }
        }
    }
    repositories {
        maven {
            val baseUrl = "https://${project.properties["nexus.host"].toString()}:${project.properties["nexus.port.jar"].toString()}/repository"
            url = uri(if (version.toString().endsWith("SNAPSHOT")) "$baseUrl/maven-snapshots" else "$baseUrl/maven-releases")
            credentials {
                username = project.properties["nexus.user"].toString()
                password = project.properties["nexus.password"].toString()
            }
        }
    }
}

Lastly, you want to make sure you include the properties file that will tell the microservices where the plugin class is. In Intellij's IDEA, when typing the path to the implementation-class it auto completed for me. The name of this file should reflect apply(plugin = "string") in the microservice's build.gradle.kts.

IMPLEMENTATION

This portion of the answer is going to reflect the microservice project that will be referencing the plugin. As stated above, jacoco and maven-publish still need to be added to the plugin block in the build.gradle.kts for some reason (I think because they are official gradle plugins).

To reference the plugin from the nexus server it was published to, the microservice must reference it in the buildscript.

buildscript { // Custom plugin must be accessed by this buildscript
    repositories {
        maven {
            url = uri("https://${project.properties["nexus.host"].toString()}:${project.properties["nexus.port.jar"].toString()}/repository/maven-public")
            credentials {
                username = project.properties["nexus.user"].toString()
                password = project.properties["nexus.password"].toString()
            }
        }
    }
    dependencies { classpath("com.company:kotlin-consolidated-plugin:1.0.0-SNAPSHOT") }
}

Lastly, the plugin must be applied using the properties file name referenced above.

apply(plugin = "com.company.kotlinconsolidatedplugin") // Custom plugin cannot reside in plugin declaration above

I created sample projects of these and posted them to Github so feel free to clone or take a look: git@github.com:diendanyoi54/kotlin-consolidated-plugin.git

git@github.com:diendanyoi54/kotlin-consolidated-plugin-implementation.git

Answer 2

I was able to successfully able to use the github repo examples referenced above to accomplish what I needed with the publish task. Here is my custom plugin's build.gradle.kts.

plugins {
    id("com.google.cloud.tools.jib") version "1.6.1"
    id("org.sonarqube") version "2.7.1"
    kotlin("jvm") version "1.3.0"
    `maven-publish`
}

dependencies {
    compile(kotlin("stdlib"))
    compile(kotlin("reflect"))
    implementation(gradleApi())
}

repositories {
    jcenter()
}

publishing {
    publications {
        create<MavenPublication>(project.name) {
            from(components["java"])
            pom {
                scm {
                    connection.set("scm:git:git@github.com:company/${project.name}.git")
                    developerConnection.set("scm:git:git@github.com:company/${project.name}.git")
                    url.set("https://github.com/company/${project.name}/")
                }
            }
        }
    }
    repositories {
        maven {
            val baseUrl = "https://${project.properties["nexus.host"].toString()}:${project.properties["nexus.port.jar"].toString()}/repository"
            url = uri(if (version.toString().endsWith("SNAPSHOT")) "$baseUrl/maven-snapshots" else "$baseUrl/maven-releases")
            credentials {
                username = project.properties["nexus.user"].toString()
                password = project.properties["nexus.password"].toString()
            }
        }
    }
}

Here is the CustomPlugin.kt class.

package com.company.gradlemicroserviceplugin

//import com.google.cloud.tools.jib.gradle.JibExtension
import org.gradle.api.Plugin
import org.gradle.api.Project
import org.gradle.api.publish.PublishingExtension
import org.gradle.api.publish.maven.MavenPublication
import org.gradle.api.publish.plugins.PublishingPlugin
import org.gradle.testing.jacoco.tasks.JacocoReport
import java.net.URI

open class CustomPlugin : Plugin<Project> {
    override fun apply(project: Project) {
//        applySonar(project)
        applyPublish(project)
//        applyJib(project)
    }

//    private fun applySonar(project: Project) {
//        project.pluginManager.apply("sonarqube")
//        val task = project.task("jacocoTestReport") as JacocoReport
//        task.reports = JacocoReport()
//        jacocoTestReport { This was nested in the tasks declaration in build.gradle.kts so the fields below are the fields I'm trying to set in task.reports
//            reports {
//                html.isEnabled = false
//                xml.isEnabled = true
//            }
//        }
//    }

    private fun applyPublish(project: Project) {
        project.pluginManager.apply(PublishingPlugin::class.java)

        val publishingExtension = project.extensions.findByType(PublishingExtension::class.java)
        val mavenPublication = publishingExtension?.publications?.create(project.name, MavenPublication::class.java)

        publishingExtension?.repositories?.maven {
            val baseUrl = "https://${project.properties["nexus.host"].toString()}:${project.properties["nexus.port.jar"].toString()}/repository"
            it.url = URI(if (project.version.toString().endsWith("SNAPSHOT")) "$baseUrl/maven-snapshots" else "$baseUrl/maven-releases")
            it.credentials { cred ->
                cred.username = project.properties["nexus.user"].toString()
                cred.password = project.properties["nexus.password"].toString()
            }
        }

        mavenPublication?.from(project.components.findByName("java"))
        mavenPublication?.pom?.scm {
            it.connection.set("scm:git:git@github.com:company/${project.name}.git")
            it.developerConnection.set("scm:git:git@github.com:company/${project.name}.git")
            it.url.set("https://github.com/company/${project.name}/")
        }
    }

//    private fun applyJib(project: Project) {
//        project.pluginManager.apply(JibPlugin::class.java)
//
//    }
}

There are definitely areas of improvement on this but at least I got something working here. There is maven-publish logic in both build.gradle.kts because I push to the custom plugin to nexus and the maven-publish logic is in the CustomPlugin.kt class so the microservice that references this plugin can use it. However, I am unable to successfully setup Jib and Sonar. Jib doesn't give me access to anything in com.google.cloud.tools.jib.gradle preventing me from using the same approach as I used in maven-publish. For Sonar I think I'm on the right track with retrieving the task by its name but I'm unable to set any fields that belong to task.reports because they are all final and this is necessary for Sonar to properly analyze Kotlin.

Answer 3

Applying built-in plugins

plugins {
java
id("jacoco")
}

You can also use the older apply syntax:

apply(plugin = "checkstyle")

Applying external plugins

plugins {
    id("org.springframework.boot") version "2.0.1.RELEASE"
}

i am not good in kotlin but here is link to better understanding missing migration guide to the Gradle Kotlin DSL