Refactor gradle-plugin build configuration to allow other plugins

So other plugins can be added to separate subprojects

README.md

@@ -12,6 +12,6 @@ at https://android.googlesource.com/platform/frameworks/support.
    * `examples` - examples of multiplatform Compose applications for Desktop and Android
        * `imageviewer` - Image Viewer application for Android and Desktop
        * `issues` - GitHub issue tracker with an adaptive UI and ktor-client
-   * `gradle-plugin` - plugin for simpler usage of Compose with Gradle build
+   * `gradle-plugins` - plugins, simplifying usage of Compose with Gradle
    * `templates` - new application templates (see `desktop-template/build_and_run_from_cli_example.sh` for using without Gradle)
    * `tutorials` - tutorials on using Compose for Desktop

gradle-plugin/.idea/vcs.xml

@@ -1,7 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<project version="4">
-  <component name="VcsDirectoryMappings">
-    <mapping directory="" vcs="Git" />
-    <mapping directory="$PROJECT_DIR$/.." vcs="Git" />
-  </component>
-</project>

gradle-plugin/README.md

@@ -1,5 +0,0 @@
-Jetpack Compose gradle plugin for easy configuration
-
-Environment variables:
-COMPOSE_GRADLE_PLUGIN_VERSION - version of plugin
-COMPOSE_GRADLE_PLUGIN_COMPOSE_VERSION - version of Jetpack Compose which will be used when the plugin is applied

gradle-plugin/build.gradle.kts

@@ -1,88 +0,0 @@
-plugins {
-    kotlin("jvm") version "1.4.0"
-    id("com.gradle.plugin-publish") version "0.10.1"
-    id("de.fuerstenau.buildconfig") version "1.1.8"
-    id("java-gradle-plugin")
-    id("maven-publish")
-}
-
-private object Info {
-    const val name = "Jetpack Compose Plugin"
-    const val website = "https://jetbrains.org/compose"
-    const val description = "Jetpack Compose gradle plugin for easy configuration"
-    const val artifactId = "compose-gradle-plugin"
-    val composeVersion = System.getenv("COMPOSE_GRADLE_PLUGIN_COMPOSE_VERSION") ?: "0.1.0-SNAPSHOT"
-    val version = System.getenv("COMPOSE_GRADLE_PLUGIN_VERSION") ?: composeVersion
-}
-
-group = "org.jetbrains.compose"
-version = Info.version
-
-java {
-    sourceCompatibility = JavaVersion.VERSION_1_8
-    targetCompatibility = JavaVersion.VERSION_1_8
-}
-
-repositories {
-    maven("https://dl.bintray.com/kotlin/kotlin-dev")
-    jcenter()
-    mavenLocal()
-}
-
-dependencies {
-    implementation(gradleApi())
-    implementation(localGroovy())
-    compileOnly("org.jetbrains.kotlin:kotlin-gradle-plugin")
-    testImplementation(gradleTestKit())
-}
-
-buildConfig {
-    packageName = "org.jetbrains.compose"
-    clsName = "ComposeBuildConfig"
-    buildConfigField("String", "composeVersion", Info.composeVersion)
-}
-
-gradlePlugin {
-    plugins {
-        create("compose") {
-            id = "org.jetbrains.compose"
-            displayName = Info.name
-            description = Info.description
-            implementationClass = "org.jetbrains.compose.ComposePlugin"
-            version = project.version
-        }
-    }
-}
-
-pluginBundle {
-    website = Info.website
-    description = Info.description
-}
-
-publishing {
-    repositories {
-        maven {
-            setUrl(System.getenv("COMPOSE_REPO_URL"))
-            credentials {
-                username = System.getenv("COMPOSE_REPO_USERNAME")
-                password = System.getenv("COMPOSE_REPO_KEY")
-            }
-        }
-    }
-    publications {
-        create<MavenPublication>("pluginMaven") {
-            artifactId = Info.artifactId
-            pom {
-                name.set(Info.name)
-                description.set(Info.description)
-                url.set(Info.website)
-                licenses {
-                    license {
-                        name.set("The Apache License, Version 2.0")
-                        url.set("http://www.apache.org/licenses/LICENSE-2.0.txt")
-                    }
-                }
-            }
-        }
-    }
-}

gradle-plugins/README.md

@@ -0,0 +1,5 @@
+Jetpack Compose gradle plugin for easy configuration
+
+Environment variables:
+* `COMPOSE_GRADLE_PLUGIN_VERSION` - version of plugin
+* `COMPOSE_GRADLE_PLUGIN_COMPOSE_VERSION` - version of Jetpack Compose used by the plugin

gradle-plugins/build.gradle.kts

@@ -0,0 +1,83 @@
+import com.gradle.publish.PluginBundleExtension
+
+plugins {
+    kotlin("jvm") version "1.4.0" apply false
+    id("com.gradle.plugin-publish") version "0.10.1" apply false
+    id("de.fuerstenau.buildconfig") version "1.1.8" apply false
+}
+
+subprojects {
+    group = BuildProperties.group
+    version = BuildProperties.version
+
+    repositories {
+        maven("https://dl.bintray.com/kotlin/kotlin-dev")
+        jcenter()
+        mavenLocal()
+    }
+
+    plugins.withId("java") {
+        configureIfExists<JavaPluginExtension> {
+            sourceCompatibility = JavaVersion.VERSION_1_8
+            targetCompatibility = JavaVersion.VERSION_1_8
+        }
+    }
+
+    plugins.withId("maven-publish") {
+        configureIfExists<PublishingExtension> {
+            repositories {
+                maven("ComposeRepo") {
+                    setUrl(System.getenv("COMPOSE_REPO_URL"))
+                    credentials {
+                        username = System.getenv("COMPOSE_REPO_USERNAME")
+                        password = System.getenv("COMPOSE_REPO_KEY")
+                    }
+                }
+            }
+        }
+    }
+
+    afterEvaluate {
+        gradlePluginConfig?.let { configureGradlePlugin(it) }
+    }
+}
+
+fun Project.configureGradlePlugin(config: GradlePluginConfigExtension) {
+    // maven publication for plugin
+    configureIfExists<PublishingExtension> {
+        publications.create<MavenPublication>("gradlePlugin") {
+            artifactId = config.artifactId
+            pom {
+                name.set(config.displayName)
+                description.set(config.description)
+                url.set(BuildProperties.website)
+                licenses {
+                    license {
+                        name.set("The Apache License, Version 2.0")
+                        url.set("http://www.apache.org/licenses/LICENSE-2.0.txt")
+                    }
+                }
+            }
+        }
+    }
+
+    // metadata for gradle plugin portal (relates to pluginBundle extension block from com.gradle.plugin-publish)
+    configureIfExists<PluginBundleExtension> {
+        vcsUrl = BuildProperties.vcs
+        website = BuildProperties.website
+        description = config.description
+    }
+
+    // gradle plugin definition (relates to gradlePlugin extension block from java-gradle-plugin)
+    configureIfExists<GradlePluginDevelopmentExtension> {
+        plugins {
+            create("gradlePlugin") {
+                id = config.pluginId
+                displayName = config.displayName
+                description = config.description
+                implementationClass = config.implementationClass
+                version = project.version
+            }
+        }
+    }
+}

gradle-plugins/buildSrc/build.gradle.kts

@@ -0,0 +1,12 @@
+plugins {
+    `kotlin-dsl`
+}
+
+repositories {
+    gradlePluginPortal()
+}
+
+dependencies {
+    compileOnly(gradleApi())
+    implementation(kotlin("stdlib"))
+}

gradle-plugins/buildSrc/settings.gradle.kts

@@ -0,0 +1,5 @@
+pluginManagement {
+    repositories {
+        gradlePluginPortal()
+    }
+}

gradle-plugins/buildSrc/src/main/kotlin/BuildProperties.kt

@@ -0,0 +1,11 @@
+// "Global" properties
+object BuildProperties {
+    const val name = "Jetpack Compose Plugin"
+    const val group = "org.jetbrains.compose"
+    const val website = "https://jetbrains.org/compose"
+    const val vcs = "https://github.com/JetBrains/compose-jb"
+    val composeVersion: String
+        get() = System.getenv("COMPOSE_GRADLE_PLUGIN_COMPOSE_VERSION") ?: "0.1.0-SNAPSHOT"
+    val version: String
+        get() = System.getenv("COMPOSE_GRADLE_PLUGIN_VERSION") ?: composeVersion
+}

gradle-plugins/buildSrc/src/main/kotlin/GradlePluginConfigExtension.kt

@@ -0,0 +1,17 @@
+import org.gradle.api.Project
+
+// Plugin-specific properties (also see gradle-plugins/build.gradle.kts)
+open class GradlePluginConfigExtension {
+    lateinit var pluginId: String
+    lateinit var artifactId: String
+    lateinit var implementationClass: String
+    lateinit var displayName: String
+    lateinit var description: String
+}
+
+val Project.gradlePluginConfig: GradlePluginConfigExtension?
+    get() = extensions.findByType(GradlePluginConfigExtension::class.java)
+
+fun Project.gradlePluginConfig(fn: GradlePluginConfigExtension.() -> Unit) {
+    extensions.create("gradlePluginConfig", GradlePluginConfigExtension::class.java).apply(fn)
+}

gradle-plugins/buildSrc/src/main/kotlin/gradleUtils.kt

@@ -0,0 +1,5 @@
+import org.gradle.api.Project
+
+inline fun <reified T> Project.configureIfExists(fn: T.() -> Unit) {
+    extensions.findByType(T::class.java)?.fn()
+}

gradle-plugins/compose/build.gradle.kts

@@ -0,0 +1,28 @@
+plugins {
+    kotlin("jvm")
+    id("de.fuerstenau.buildconfig")
+    id("com.gradle.plugin-publish")
+    id("java-gradle-plugin")
+    id("maven-publish")
+}
+
+gradlePluginConfig {
+    pluginId = "org.jetbrains.compose"
+    artifactId = "compose-gradle-plugin"
+    displayName = "Jetpack Compose Plugin"
+    description = "Jetpack Compose gradle plugin for easy configuration"
+    implementationClass = "org.jetbrains.compose.ComposePlugin"
+}
+
+buildConfig {
+    packageName = "org.jetbrains.compose"
+    clsName = "ComposeBuildConfig"
+    buildConfigField("String", "composeVersion", BuildProperties.composeVersion)
+}
+
+dependencies {
+    compileOnly(gradleApi())
+    compileOnly(localGroovy())
+    compileOnly("org.jetbrains.kotlin:kotlin-gradle-plugin")
+    testImplementation(gradleTestKit())
+}

gradle-plugins/settings.gradle.kts

@@ -3,4 +3,6 @@ pluginManagement {
         gradlePluginPortal()
         maven("https://dl.bintray.com/kotlin/kotlin-dev")
     }
-}
+}
+
+include(":compose")