Add Kotlin support

Closes gh-147

initializr-service/application.yml

@@ -34,6 +34,7 @@ initializr:
         version: 1.0.0.BUILD-SNAPSHOT
         additionalBoms: [cloud-bom]
         repositories: spring-snapshots,spring-milestones
+    kotlinVersion: 1.0.0-beta-2423
   dependencies:
     - name: Core
       content:
@@ -630,6 +631,9 @@ initializr:
     - name: Groovy
       id: groovy
       default: false
+    - name: Kotlin
+      id: kotlin
+      default: false
   bootVersions:
     - name : Latest SNAPSHOT
       id: 1.2.4.BUILD-SNAPSHOT

initializr/src/main/groovy/io/spring/initializr/generator/ProjectGenerator.groovy

@@ -124,10 +124,11 @@ class ProjectGenerator {
 		def applicationName = request.applicationName
 		def language = request.language
 
-		String codeLocation = language.equals("groovy") ? 'groovy': 'java'
+		String codeLocation = language
 		def src = new File(new File(dir, "src/main/$codeLocation"), request.packageName.replace('.', '/'))
 		src.mkdirs()
-		write(new File(src, "${applicationName}.${language}"), "Application.$language", model)
+		def extension = (language.equals('kotlin') ? 'kt' : language)
+		write(new File(src, "${applicationName}.${extension}"), "Application.$extension", model)
 
 		if (request.packaging == 'war') {
 			def fileName = "ServletInitializer.$language"
@@ -143,7 +144,7 @@ class ProjectGenerator {
 			model.testAnnotations = ''
 			model.testImports = ''
 		}
-		write(new File(test, "${applicationName}Tests.${language}"), "ApplicationTests.$language", model)
+		write(new File(test, "${applicationName}Tests.${extension}"), "ApplicationTests.$extension", model)
 
 		def resources = new File(dir, 'src/main/resources')
 		resources.mkdirs()

initializr/src/main/groovy/io/spring/initializr/generator/ProjectRequest.groovy

@@ -141,6 +141,8 @@ class ProjectRequest extends BasicProjectRequest {
 
 		initializeRepositories(metadata, requestedVersion)
 
+		kotlinVersion = metadata.configuration.env.kotlinVersion
+
 		afterResolution(metadata)
 	}
 

initializr/src/main/groovy/io/spring/initializr/metadata/InitializrConfiguration.groovy

@@ -154,6 +154,11 @@ class InitializrConfiguration {
 		 */
 		boolean forceSsl = true
 
+		/**
+		 * Kotlin version
+		 */
+		String kotlinVersion
+
 		/**
 		 * The "BillOfMaterials" that are referenced in this instance, identified by an
 		 * arbitrary identifier that can be used in the dependencies definition.
@@ -193,6 +198,7 @@ class InitializrConfiguration {
 			fallbackApplicationName = other.fallbackApplicationName
 			invalidApplicationNames = other.invalidApplicationNames
 			forceSsl = other.forceSsl
+			kotlinVersion = other.kotlinVersion
 			other.boms.each { id, bom ->
 				if (!boms[id]) {
 					boms[id] = bom

initializr/src/main/resources/templates/Application.kt

@@ -0,0 +1,17 @@
+package ${packageName}
+
+import org.springframework.boot.SpringApplication<% if (useSpringBootApplication) { %>
+import org.springframework.boot.autoconfigure.SpringBootApplication<% } else { %>
+import org.springframework.boot.autoconfigure.EnableAutoConfiguration
+import org.springframework.context.annotation.ComponentScan
+import org.springframework.context.annotation.Configuration<% } %>
+<% if (useSpringBootApplication) { %>
+@SpringBootApplication<% } else { %>
+@Configuration
+@ComponentScan
+@EnableAutoConfiguration <% } %>
+open class ${applicationName}
+
+fun main(args: Array<String>) {
+    SpringApplication.run(${applicationName}::class.java, *args)
+}

initializr/src/main/resources/templates/ApplicationTests.kt

@@ -0,0 +1,16 @@
+package ${packageName}
+
+import org.junit.Test
+import org.junit.runner.RunWith
+${testImports}import org.springframework.boot.test.SpringApplicationConfiguration
+import org.springframework.test.context.junit4.SpringJUnit4ClassRunner
+
+@RunWith(SpringJUnit4ClassRunner::class)
+@SpringApplicationConfiguration(classes = arrayOf(${applicationName}::class))
+${testAnnotations}class ${applicationName}Tests {
+
+	@Test
+	fun contextLoads() {
+	}
+
+}

initializr/src/main/resources/templates/ServletInitializer.kt

@@ -0,0 +1,12 @@
+package ${packageName}
+
+import org.springframework.boot.builder.SpringApplicationBuilder
+import org.springframework.boot.context.web.SpringBootServletInitializer
+
+class ServletInitializer : SpringBootServletInitializer() {
+
+	override fun configure(application: SpringApplicationBuilder) : SpringApplicationBuilder {
+		return application.sources(${applicationName}::class.java)
+	}
+
+}

initializr/src/main/resources/templates/starter-build.gradle

@@ -1,6 +1,7 @@
 buildscript {
 	ext {
-		springBootVersion = '${bootVersion}'
+		springBootVersion = '${bootVersion}'<% if (language=='kotlin') { %>
+			kotlinVersion = '${kotlinVersion}'<% } %>
 	}
 	repositories {
 		mavenCentral()<% if (!bootVersion.contains("RELEASE")) { %>
@@ -9,7 +10,8 @@ buildscript {
 	}
 	dependencies {
 		classpath("org.springframework.boot:spring-boot-gradle-plugin:\${springBootVersion}") <% if (!bootOneThreeAvailable) { %>
-		classpath('io.spring.gradle:dependency-management-plugin:0.5.4.RELEASE')<% } %>
+		classpath('io.spring.gradle:dependency-management-plugin:0.5.4.RELEASE')<% } %><% if (language=='kotlin') { %>
+		classpath("org.jetbrains.kotlin:kotlin-gradle-plugin:\${kotlinVersion}")<% } %>
 	}
 }
 
@@ -39,8 +41,10 @@ repositories {
 <% } %>
 dependencies {<% compileDependencies.each { %>
 	compile('${it.groupId}:${it.artifactId}${it.version ? ":$it.version" : ""}')<% } %><% if (language=='groovy') { %>
-	compile('org.codehaus.groovy:groovy')<% } %><% runtimeDependencies.each { %>
-	runtime('${it.groupId}:${it.artifactId}${it.version ? ":$it.version" : ""}')<% } %><% providedDependencies.each { %>
+	compile('org.codehaus.groovy:groovy')<% } %><% if (language=='kotlin') { %>
+	compile("org.jetbrains.kotlin:kotlin-stdlib:\${kotlinVersion}")<% } %><% runtimeDependencies.each { %>
+	runtime('${it.groupId}:${it.artifactId}${it.version ? ":$it.version" : ""}')<% } %><% if (packaging=='war') { %>
+	providedRuntime('org.springframework.boot:spring-boot-starter-tomcat')<% } %><% providedDependencies.each { %>
 	providedRuntime('${it.groupId}:${it.artifactId}${it.version ? ":$it.version" : ""}')<% } %>
 	testCompile('org.springframework.boot:spring-boot-starter-test') <% testDependencies.each { %>
 	testCompile('${it.groupId}:${it.artifactId}${it.version ? ":$it.version" : ""}')<% } %>

initializr/src/main/resources/templates/starter-pom.xml

@@ -20,7 +20,8 @@
 
 	<properties>
 		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-		<java.version>${javaVersion}</java.version>
+		<java.version>${javaVersion}</java.version><% if (language=='kotlin') { %>
+		<kotlin.version>${kotlinVersion}</kotlin.version><% } %>
 	</properties>
 
 	<dependencies><% compileDependencies.each { %>
@@ -32,6 +33,11 @@
 		<dependency>
 			<groupId>org.codehaus.groovy</groupId>
 			<artifactId>groovy</artifactId>
+		</dependency><% } %><% if (language=='kotlin') { %>
+		<dependency>
+			<groupId>org.jetbrains.kotlin</groupId>
+			<artifactId>kotlin-stdlib</artifactId>
+			<version>\${kotlin.version}</version>
 		</dependency><% } %>
 		<% runtimeDependencies.each { %>
 		<dependency>
@@ -71,7 +77,9 @@
 		</dependencies>
 	</dependencyManagement>
 	<% } %>
-	<build>
+	<build><% if (language=='kotlin') { %>
+		<sourceDirectory>\${project.basedir}/src/main/kotlin</sourceDirectory>
+		<testSourceDirectory>\${project.basedir}/src/test/kotlin</testSourceDirectory><% } %>
 		<plugins>
 			<plugin>
 				<groupId>org.springframework.boot</groupId>
@@ -95,6 +103,27 @@
 						</goals>
 					</execution>
 				</executions>
+			</plugin><% } %><% if (language=='kotlin') { %>
+			<plugin>
+				<artifactId>kotlin-maven-plugin</artifactId>
+				<groupId>org.jetbrains.kotlin</groupId>
+				<version>\${kotlin.version}</version>
+				<executions>
+					<execution>
+						<id>compile</id>
+						<phase>compile</phase>
+						<goals>
+							<goal>compile</goal>
+						</goals>
+					</execution>
+					<execution>
+						<id>test-compile</id>
+						<phase>test-compile</phase>
+						<goals>
+							<goal>test-compile</goal>
+						</goals>
+					</execution>
+				</executions>
 			</plugin><% } %>
 		</plugins>
 	</build>

initializr/src/test/groovy/io/spring/initializr/generator/ProjectGenerationMetricsListenerTests.groovy

@@ -164,7 +164,7 @@ class ProjectGenerationMetricsListenerTests {
 	}
 
 	@Test
-	void explicitLanguage() {
+	void explicitGroovyLanguage() {
 		def request = initialize()
 		request.language = 'groovy'
 		request.resolve(metadata)
@@ -172,6 +172,15 @@ class ProjectGenerationMetricsListenerTests {
 		metricsAssert.hasValue(1, 'initializr.language.groovy')
 	}
 
+	@Test
+	void explicitKotlinLanguage() {
+		def request = initialize()
+		request.language = 'kotlin'
+		request.resolve(metadata)
+		listener.onGeneratedProject(request)
+		metricsAssert.hasValue(1, 'initializr.language.kotlin')
+	}
+
 	@Test
 	void defaultBootVersion() {
 		def request = initialize()

initializr/src/test/groovy/io/spring/initializr/generator/ProjectGeneratorTests.groovy

@@ -238,6 +238,34 @@ class ProjectGeneratorTests {
 				.doesNotContain('@EnableAutoConfiguration', '@Configuration', '@ComponentScan')
 	}
 
+	@Test
+	void springBoot11UseEnableAutoConfigurationKotlin() {
+		def request = createProjectRequest('web')
+		request.language = 'kotlin'
+		request.bootVersion = '1.1.9.RELEASE'
+		request.name = 'MyDemo'
+		request.packageName = 'foo'
+		generateProject(request).sourceCodeAssert('src/main/kotlin/foo/MyDemoApplication.kt')
+				.hasImports(EnableAutoConfiguration.class.name, ComponentScan.class.name, Configuration.class.name)
+				.doesNotHaveImports(SpringBootApplication.class.name)
+				.contains('@EnableAutoConfiguration', '@Configuration', '@ComponentScan')
+				.doesNotContain('@SpringBootApplication')
+	}
+
+	@Test
+	void springBootUseSpringBootApplicationKotlin() {
+		def request = createProjectRequest('web')
+		request.language = 'kotlin'
+		request.bootVersion = '1.2.0.RC1'
+		request.name = 'MyDemo'
+		request.packageName = 'foo'
+		generateProject(request).sourceCodeAssert('src/main/kotlin/foo/MyDemoApplication.kt')
+				.hasImports(SpringBootApplication.class.name)
+				.doesNotHaveImports(EnableAutoConfiguration.class.name, ComponentScan.class.name, Configuration.class.name)
+				.contains('@SpringBootApplication')
+				.doesNotContain('@EnableAutoConfiguration', '@Configuration', '@ComponentScan')
+	}
+
 	@Test
 	void customBaseDirectory() {
 		def request = createProjectRequest()

initializr/src/test/groovy/io/spring/initializr/metadata/InitializrMetadataBuilderTests.groovy

@@ -76,7 +76,7 @@ class InitializrMetadataBuilderTests {
 		assertEquals 2, metadata.bootVersions.content.size()
 		assertEquals 2, metadata.packagings.content.size()
 		assertEquals 1, metadata.javaVersions.content.size()
-		assertEquals 2, metadata.languages.content.size()
+		assertEquals 3, metadata.languages.content.size()
 		assertEquals 'meta-data-merge', metadata.name.content
 		assertEquals 'Demo project for meta-data merge', metadata.description.content
 		assertEquals 'org.acme', metadata.groupId.content
@@ -138,6 +138,7 @@ class InitializrMetadataBuilderTests {
 		assertEquals defaultEnv.springBootMetadataUrl, actualEnv.springBootMetadataUrl
 		assertEquals defaultEnv.fallbackApplicationName, actualEnv.fallbackApplicationName
 		assertEquals defaultEnv.forceSsl, actualEnv.forceSsl
+		assertEquals defaultEnv.kotlinVersion, actualEnv.kotlinVersion
 	}
 
 	@Test
@@ -153,6 +154,7 @@ class InitializrMetadataBuilderTests {
 		assertEquals defaultEnv.springBootMetadataUrl, actualEnv.springBootMetadataUrl
 		assertEquals 'FooBarApplication', actualEnv.fallbackApplicationName
 		assertEquals false, actualEnv.forceSsl
+		assertEquals '1.0.0-beta-2423', actualEnv.kotlinVersion
 	}
 
 	@Test

initializr/src/test/groovy/io/spring/initializr/test/InitializrMetadataTestBuilder.groovy

@@ -117,7 +117,7 @@ class InitializrMetadataTestBuilder {
 	}
 
 	InitializrMetadataTestBuilder addDefaultLanguages() {
-		addLanguage('java', true).addLanguage('groovy', false)
+		addLanguage('java', true).addLanguage('groovy', false).addLanguage('kotlin', false)
 	}
 
 	InitializrMetadataTestBuilder addLanguage(String id, boolean defaultValue) {

initializr/src/test/groovy/io/spring/initializr/test/ProjectAssert.groovy

@@ -115,10 +115,20 @@ class ProjectAssert {
 				'src/main/resources/application.properties')
 	}
 
+	ProjectAssert isKotlinProject(String expectedApplicationName) {
+		hasFile("src/main/kotlin/com/example/${expectedApplicationName}.kt",
+				"src/test/kotlin/com/example/${expectedApplicationName}Tests.kt",
+				'src/main/resources/application.properties')
+	}
+
 	ProjectAssert isGroovyProject() {
 		isGroovyProject(DEFAULT_PACKAGE_NAME, DEFAULT_APPLICATION_NAME)
 	}
 
+	ProjectAssert isKotlinProject() {
+		isKotlinProject(DEFAULT_APPLICATION_NAME)
+	}
+
 	ProjectAssert isJavaWarProject(String expectedApplicationName) {
 		isJavaProject(DEFAULT_PACKAGE_NAME, expectedApplicationName)
 				.hasStaticAndTemplatesResources(true)

initializr/src/test/groovy/io/spring/initializr/web/ProjectGenerationSmokeTests.groovy

@@ -201,6 +201,21 @@ class ProjectGenerationSmokeTests extends AbstractInitializrControllerIntegratio
 		}
 	}
 
+	@Test
+	void createDefaultKotlinProject() {
+		toHome {
+			page.language = 'kotlin'
+			page.generateProject.click()
+			at HomePage
+			def projectAssert = zipProjectAssert(from('demo.zip'))
+			projectAssert.hasBaseDir('demo').isMavenProject().isKotlinProject()
+					.hasStaticAndTemplatesResources(false)
+					.pomAssert().hasDependenciesCount(3)
+					.hasSpringBootStarterRootDependency().hasSpringBootStarterTest()
+					.hasDependency('org.jetbrains.kotlin', 'kotlin-stdlib')
+		}
+	}
+
 
 	@Test
 	void createWarProject() {
@@ -280,6 +295,31 @@ class ProjectGenerationSmokeTests extends AbstractInitializrControllerIntegratio
 		}
 	}
 
+	@Test
+	void createKotlinProjectWithCustomDefaults() {
+		toHome {
+			page.language = 'kotlin'
+			page.groupId = 'org.biz'
+			page.artifactId = 'kotlin-project'
+			page.name = 'My Kotlin project'
+			page.description = 'A description for my Kotlin project'
+			page.dependency('web').click()
+			page.dependency('data-jpa').click()
+			page.generateProject.click()
+			at HomePage
+			def projectAssert = zipProjectAssert(from('kotlin-project.zip'))
+			projectAssert.hasBaseDir("kotlin-project").isMavenProject()
+					.isGroovyProject('MyKotlinProjectApplication')
+					.hasStaticAndTemplatesResources(true)
+					.pomAssert().hasGroupId('org.biz').hasArtifactId('kotlin-project')
+					.hasName('My Kotlin project').hasDescription('A description for my Kotlin project')
+					.hasSpringBootStarterDependency('web')
+					.hasSpringBootStarterDependency('data-jpa')
+					.hasSpringBootStarterTest()
+					.hasDependency('org.jetbrains.kotlin', 'kotlin-stdlib')
+		}
+	}
+
 	@Test
 	void dependencyHiddenAccordingToRange() {
 		toHome { // bur: [1.1.4.RELEASE,1.2.0.BUILD-SNAPSHOT)

initializr/src/test/resources/application-test-custom-env.yml

@@ -6,3 +6,4 @@ initializr:
     fallbackApplicationName: FooBarApplication
     invalidApplicationNames:
       - InvalidApplication
+    kotlinVersion: 1.0.0-beta-2423

initializr/src/test/resources/application-test-default.yml

@@ -129,6 +129,9 @@ initializr:
     - name: Java
       id: java
       default: true
+    - name: Kotlin
+      id: kotlin
+      default: false
   bootVersions:
     - name : Latest SNAPSHOT
       id: 1.2.0.BUILD-SNAPSHOT

initializr/src/test/resources/metadata/config/test-default.json

@@ -33,6 +33,7 @@
     "artifactRepository": "https://repo.spring.io/release/",
     "fallbackApplicationName": "Application",
     "forceSsl": true,
+    "kotlinVersion": null,
     "googleAnalyticsTrackingCode": null,
     "invalidApplicationNames": [
       "SpringApplication",
@@ -250,6 +251,11 @@
         "default": true,
         "id": "java",
         "name": "Java"
+      },
+      {
+        "default": false,
+        "id": "kotlin",
+        "name": "Kotlin"
       }
     ],
     "description": "programming language",

initializr/src/test/resources/metadata/config/test-min.json

@@ -101,6 +101,11 @@
         "name": "Java",
         "id": "java",
         "default": true
+      },
+      {
+        "name": "Kotlin",
+        "id": "kotlin",
+        "default": false
       }
     ]
   },

initializr/src/test/resources/metadata/test-default-2.0.0.json

@@ -142,6 +142,10 @@
       {
         "id": "java",
         "name": "Java"
+      },
+      {
+        "id": "kotlin",
+        "name": "Kotlin"
       }
     ]
   },

initializr/src/test/resources/metadata/test-default-2.1.0.json

@@ -156,6 +156,10 @@
       {
         "id": "java",
         "name": "Java"
+      },
+      {
+        "id": "kotlin",
+        "name": "Kotlin"
       }
     ]
   },