Add Kotlin Template to Spring Boot Stack (#107)

* Add Kotlin support

* Test Kotlin endpoint

incubator/java-spring-boot2/image/Dockerfile-stack

@@ -3,11 +3,20 @@ LABEL maintainer="IBM Java Engineering at IBM Cloud"
 
 # Ensure up to date / patched OS
 RUN  apt-get -qq update \
-  && apt-get -qq install -y curl wget xmlstarlet \
+  && apt-get -qq install -y curl wget xmlstarlet unzip \
   && DEBIAN_FRONTEND=noninteractive apt-get -qq upgrade -y \
   && apt-get -qq clean \
   && rm -rf /tmp/* /var/lib/apt/lists/*
 
+# Kotlin support
+COPY ./project/stack.properties /project/stack.properties
+RUN cd /usr/lib && \
+    KVER=$(cat /project/stack.properties | grep kotlin.version | sed 's/kotlin.version=//') && \
+    wget -q https://github.com/JetBrains/kotlin/releases/download/v$KVER/kotlin-compiler-$KVER.zip && \
+    unzip kotlin-compiler-*.zip && \
+    rm kotlin-compiler-*.zip && \
+    rm -f kotlinc/bin/*.bat  
+
 COPY ./project /project
 COPY ./mvn-stack-settings.xml /usr/share/maven/conf/settings.xml
 COPY ./mvn-stack-settings.xml /project/.mvn-stack-settings.xml

incubator/java-spring-boot2/image/project/Dockerfile

@@ -3,12 +3,21 @@ LABEL maintainer="IBM Java Engineering at IBM Cloud"
 
 # Ensure up to date / patched OS
 RUN  apt-get -qq update \
-  && apt-get -qq install -y curl wget xmlstarlet \
+  && apt-get -qq install -y curl wget xmlstarlet unzip \
   && DEBIAN_FRONTEND=noninteractive apt-get -qq upgrade -y \
   && apt-get -qq clean \
   && rm -rf /tmp/* /var/lib/apt/lists/* \
   && mkdir -p /mvn/repository
 
+# Kotlin support
+COPY ./stack.properties /project/stack.properties
+RUN cd /usr/lib && \
+    KVER=$(cat /project/stack.properties | grep kotlin.version | sed 's/kotlin.version=//') && \
+    wget -q https://github.com/JetBrains/kotlin/releases/download/v$KVER/kotlin-compiler-$KVER.zip && \
+    unzip kotlin-compiler-*.zip && \
+    rm kotlin-compiler-*.zip && \
+    rm -f kotlinc/bin/*.bat  
+
 #setup project folder for java build step
 COPY . /project
 COPY ./.mvn-stack-settings.xml /usr/share/maven/conf/settings.xml

incubator/java-spring-boot2/image/project/appsody-boot2-pom.xml

@@ -5,7 +5,7 @@
 
   <groupId>dev.appsody</groupId>
   <artifactId>spring-boot2-stack</artifactId>
-  <version>0.3.1</version>
+  <version>0.3.2</version>
   <packaging>pom</packaging>
 
   <name>Appsody Spring Boot2 stack</name>
@@ -42,6 +42,8 @@
     <opentracing-spring-jaeger-web-starter.version>2.0.0</opentracing-spring-jaeger-web-starter.version>
 
     <java.version>1.8</java.version>
+    <kotlin.version>1.3.40</kotlin.version> <!-- matches ver in stack.properties -->
+
     <maven.compiler.source>${java.version}</maven.compiler.source>
     <maven.compiler.target>${java.version}</maven.compiler.target>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>

incubator/java-spring-boot2/image/project/stack.properties

@@ -0,0 +1 @@
+kotlin.version=1.3.40

incubator/java-spring-boot2/stack.yaml

@@ -1,9 +1,9 @@
 name: Spring Boot®
-version: 0.3.1
+version: 0.3.2
 description: Spring Boot using OpenJ9 and Maven
 license: Apache-2.0
 maintainers:
   - name: Erin Schnabel
     email: schnabel@us.ibm.com
     github-id: ebullient
-default-template: default
+default-template: default

incubator/java-spring-boot2/templates/default/pom.xml

@@ -6,7 +6,7 @@
   <parent><!--required parent POM-->
     <groupId>dev.appsody</groupId>
     <artifactId>spring-boot2-stack</artifactId>
-    <version>0.3.1</version>
+    <version>0.3.2</version>
     <relativePath/>
   </parent>
 

incubator/java-spring-boot2/templates/kotlin/.appsody-config.yaml

@@ -0,0 +1 @@
+stack: appsody/java-spring-boot2:0.3

incubator/java-spring-boot2/templates/kotlin/.gitignore

@@ -0,0 +1,27 @@
+/target/*
+
+### STS ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+/build/
+
+### VS Code ###
+.vscode/

incubator/java-spring-boot2/templates/kotlin/pom.xml

@@ -0,0 +1,136 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+
+  <parent><!--required parent POM-->
+    <groupId>dev.appsody</groupId>
+    <artifactId>spring-boot2-stack</artifactId>
+    <version>0.3.2</version>
+    <relativePath/>
+  </parent>
+
+  <groupId>dev.appsody</groupId>
+  <artifactId>application</artifactId>
+  <version>0.0.1-SNAPSHOT</version>
+  <packaging>jar</packaging>
+
+  <!-- versions will come from the parent pom (and included bom):
+    mvn dependency:tree
+    mvn dependency:display-ancestors
+    mvn help:effective-pom | grep '\.version>'
+    -->
+
+  <dependencies>
+    <!-- From parent:
+      org.springframework.boot:spring-boot-starter
+      org.springframework.boot:spring-boot-starter-actuator
+      org.springframework.boot:spring-boot-starter-test
+     -->
+    <dependency>
+      <groupId>org.jetbrains.kotlin</groupId>
+      <artifactId>kotlin-reflect</artifactId>
+    </dependency>
+    <dependency>
+      <groupId>org.jetbrains.kotlin</groupId>
+      <artifactId>kotlin-stdlib-jdk8</artifactId>
+    </dependency>     
+    <dependency>
+        <groupId>org.springframework.boot</groupId>
+        <artifactId>spring-boot-starter-web</artifactId>
+    </dependency>
+  </dependencies>
+
+  <build>
+    <plugins>
+      <plugin>
+        <groupId>org.jetbrains.kotlin</groupId>
+        <artifactId>kotlin-maven-plugin</artifactId>
+        <version>${kotlin.version}</version>
+        <executions>
+          <execution>
+              <id>compile</id>
+              <goals> 
+                <goal>compile</goal> 
+              </goals>
+              <configuration>
+                  <sourceDirs>
+                      <sourceDir>${project.basedir}/src/main/kotlin</sourceDir>
+                      <sourceDir>${project.basedir}/src/main/java</sourceDir>
+                  </sourceDirs>
+              </configuration>
+          </execution>
+          <execution>
+              <id>test-compile</id>
+              <goals>
+                <goal>test-compile</goal>
+              </goals>
+              <configuration>
+                  <sourceDirs>
+                      <sourceDir>${project.basedir}/src/test/kotlin</sourceDir>
+                      <sourceDir>${project.basedir}/src/test/java</sourceDir>
+                  </sourceDirs>
+              </configuration>
+          </execution>
+        </executions>
+        <configuration>
+           <args>
+              <arg>-Xjsr305=strict</arg>
+           </args>
+           <compilerPlugins>
+              <plugin>spring</plugin>
+           </compilerPlugins>
+        </configuration>
+        <dependencies>
+           <dependency>
+              <groupId>org.jetbrains.kotlin</groupId>
+              <artifactId>kotlin-maven-allopen</artifactId>
+              <version>${kotlin.version}</version>
+           </dependency>
+        </dependencies>
+      </plugin>
+      <plugin>
+          <groupId>org.apache.maven.plugins</groupId>
+          <artifactId>maven-compiler-plugin</artifactId>
+          <version>3.5.1</version>
+          <executions>
+              <execution>
+                  <id>default-compile</id>
+                  <phase>none</phase>
+              </execution>
+              <execution>
+                  <id>default-testCompile</id>
+                  <phase>none</phase>
+              </execution>
+              <execution>
+                  <id>java-compile</id>
+                  <phase>compile</phase>
+                  <goals> 
+                    <goal>compile</goal>
+                  </goals>
+              </execution>
+              <execution>
+                  <id>java-test-compile</id>
+                  <phase>test-compile</phase>
+                  <goals>
+                    <goal>testCompile</goal>
+                  </goals>
+              </execution>
+          </executions>
+      </plugin>      
+      <plugin>
+        <groupId>org.springframework.boot</groupId>
+        <artifactId>spring-boot-maven-plugin</artifactId>
+        <version>${spring-boot.version}</version>
+        <executions>
+          <execution>
+            <goals>
+              <goal>repackage</goal>
+            </goals>
+          </execution>
+        </executions>
+      </plugin>
+    </plugins>
+  </build>  
+
+</project>

incubator/java-spring-boot2/templates/kotlin/src/main/java/application/Main.java

@@ -0,0 +1,25 @@
+package application;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.actuate.endpoint.annotation.Endpoint;
+import org.springframework.boot.actuate.endpoint.annotation.ReadOperation;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.stereotype.Component;
+
+@SpringBootApplication
+public class Main {
+
+	public static void main(String[] args) {
+		SpringApplication.run(Main.class, args);
+	}
+
+	// Simple custom liveness check
+	@Endpoint(id = "liveness")
+	@Component
+	public class Liveness {
+		@ReadOperation
+		public String testLiveness() {
+			return "{\"status\":\"UP\"}";
+		}
+	}
+}

incubator/java-spring-boot2/templates/kotlin/src/main/kotlin/application/Hello.kt

@@ -0,0 +1,16 @@
+package application
+
+import org.springframework.web.bind.annotation.RestController
+import org.springframework.ui.Model
+import org.springframework.ui.set
+import org.springframework.web.bind.annotation.GetMapping
+
+@RestController
+class Hello {
+
+@GetMapping("/hello")
+  fun hello(): String {
+    return "Hello, Appsody!"
+  }
+
+ }

incubator/java-spring-boot2/templates/kotlin/src/main/resources/application.properties

@@ -0,0 +1,2 @@
+#enable the actuator endpoints for health, metrics, and prometheus.
+management.endpoints.web.exposure.include=health,metrics,prometheus,liveness

incubator/java-spring-boot2/templates/kotlin/src/main/resources/public/index.html

@@ -0,0 +1,23 @@
+<!DOCTYPE html>
+<html>
+  <head>
+    <title>Hello from Appsody!</title>
+  </head>
+  <body>
+    <h3>Hello from Appsody!</h3>
+    <p>Next steps with Spring Boot 2:
+      <ul>
+        <li><a target="_blank" rel="noopener" href="https://docs.spring.io/spring-boot/docs/current/reference/htmlsingle/">Spring Boot Reference Guide</a></li>
+        <li><a target="_blank" rel="noopener" href="https://spring.io/guides">Spring Guides</a></li>
+        <li><a target="_blank" rel="noopener" href="/actuator">Spring Boot Actuator endpoints</a>:
+          <ul>
+            <li><a target="_blank" rel="noopener" href="/actuator/health">Health</a></li>
+            <li><a target="_blank" rel="noopener" href="/actuator/liveness">Appsody Liveness</a></li>
+            <li><a target="_blank" rel="noopener" href="/actuator/metrics">Metrics</a></li>
+            <li><a target="_blank" rel="noopener" href="/actuator/prometheus">Prometheus</a></li>
+          </ul>
+        </li>
+      </ul>
+    </p>
+  </body>
+</html>

incubator/java-spring-boot2/templates/kotlin/src/test/java/application/MainTests.java

@@ -0,0 +1,68 @@
+package application;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import java.util.List;
+import java.util.Map;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.boot.test.context.SpringBootTest.WebEnvironment;
+import org.springframework.boot.test.web.client.TestRestTemplate;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.test.context.junit4.SpringRunner;
+
+@RunWith(SpringRunner.class)
+@SpringBootTest(webEnvironment = WebEnvironment.RANDOM_PORT)
+public class MainTests {
+
+    @Autowired
+    private TestRestTemplate restTemplate;
+
+    @Test
+    public void testHealthEndpoint() {
+        ResponseEntity<String> entity = this.restTemplate.getForEntity("/actuator/health", String.class);
+        assertThat(entity.getStatusCode()).isEqualTo(HttpStatus.OK);
+        assertThat(entity.getBody()).contains("\"status\":\"UP\"");
+    }
+
+    @Test
+    public void testKotlinEndpoint() {
+        ResponseEntity<String> entity = this.restTemplate.getForEntity("/hello", String.class);
+        assertThat(entity.getStatusCode()).isEqualTo(HttpStatus.OK);
+        assertThat(entity.getBody()).contains("Hello, Appsody!");
+    }    
+
+    @Test
+    public void testLivenessEndpoint() {
+        ResponseEntity<String> entity = this.restTemplate.getForEntity("/actuator/liveness", String.class);
+        assertThat(entity.getStatusCode()).isEqualTo(HttpStatus.OK);
+        assertThat(entity.getBody()).contains("\"status\":\"UP\"");
+    }
+
+    @Test
+    @SuppressWarnings("unchecked")
+    public void testMetricsEndpoint() {
+        testLivenessEndpoint(); // access a page
+
+        @SuppressWarnings("rawtypes")
+        ResponseEntity<Map> entity = this.restTemplate.getForEntity("/actuator/metrics", Map.class);
+        assertThat(entity.getStatusCode()).isEqualTo(HttpStatus.OK);
+
+        Map<String, Object> body = entity.getBody();
+        assertThat(body).containsKey("names");
+        assertThat((List<String>) body.get("names")).contains("jvm.buffer.count");
+    }
+
+    @Test
+    public void testPrometheusEndpoint() {
+        testLivenessEndpoint(); // access a page
+
+        ResponseEntity<String> entity = this.restTemplate.getForEntity("/actuator/prometheus", String.class);
+        assertThat(entity.getStatusCode()).isEqualTo(HttpStatus.OK);
+        assertThat(entity.getBody()).contains("# TYPE jvm_buffer_count_buffers gauge");
+    }
+}