From: Claude <noreply@anthropic.com>
Date: Sun, 17 May 2026 15:03:21 +0000 (+0000)
Subject: refactor: Docker-Build auf bootBuildImage (Cloud Native Buildpacks) umstellen
X-Git-Tag: consumer/nodlt--BACKUP-ORIGIN--LAST
X-Git-Url: http://juplo.de/gitweb/?a=commitdiff_plain;h=575c7e4cb09cd9e6bbcdd29380daa05177c84b39;p=demos%2Fkafka%2Ftraining

refactor: Docker-Build auf bootBuildImage (Cloud Native Buildpacks) umstellen

Bisher baute Maven den Docker-Image via io.fabric8:docker-maven-plugin und
ein handgepflegtes Dockerfile. Gradle kopierte das JAR umständlich in ein
target/-Verzeichnis, damit dasselbe Dockerfile funktioniert (COPY target/*.jar).

Beide Build-Systeme nutzen jetzt bootBuildImage, das über Cloud Native
Buildpacks direkt aus dem Spring Boot Plugin heraus ein OCI-Image erzeugt:

  Maven:  mvn spring-boot:build-image
  Gradle: ./gradlew bootBuildImage

Vorteile:
- Kein Dockerfile mehr nötig (und damit kein Kopier-Hack in Gradle)
- Beide Build-Systeme verwenden dieselbe Methode mit identischer Konfiguration
- Das erzeugte Image folgt automatisch Best Practices (non-root, layered JAR)
- io.fabric8:docker-maven-plugin und com.bmuschko.docker-remote-api entfallen

Entfernte Dateien: Dockerfile, .dockerignore, .maven-dockerexclude, .maven-dockerinclude
---

diff --git a/.dockerignore b/.dockerignore
deleted file mode 100644
index 6de8137a..00000000
--- a/.dockerignore
+++ /dev/null
@@ -1,3 +0,0 @@
-*
-!Dockerfile
-!target/*.jar
diff --git a/.maven-dockerexclude b/.maven-dockerexclude
deleted file mode 100644
index 72e8ffc0..00000000
--- a/.maven-dockerexclude
+++ /dev/null
@@ -1 +0,0 @@
-*
diff --git a/.maven-dockerinclude b/.maven-dockerinclude
deleted file mode 100644
index fd6cecd2..00000000
--- a/.maven-dockerinclude
+++ /dev/null
@@ -1 +0,0 @@
-target/*.jar
diff --git a/Dockerfile b/Dockerfile
deleted file mode 100644
index 9e196ff0..00000000
--- a/Dockerfile
+++ /dev/null
@@ -1,5 +0,0 @@
-FROM eclipse-temurin:21-jre
-VOLUME /tmp
-COPY target/*.jar /opt/app.jar
-ENTRYPOINT [ "java", "-jar", "/opt/app.jar" ]
-CMD []
diff --git a/build.gradle b/build.gradle
index f44d5d03..51613fb2 100644
--- a/build.gradle
+++ b/build.gradle
@@ -1,11 +1,8 @@
-import com.bmuschko.gradle.docker.tasks.image.DockerBuildImage
-
 plugins {
 	id 'java'
 	id 'org.springframework.boot' version '4.0.2'
 	id 'io.spring.dependency-management' version '1.1.7'
 	id 'com.gorylenko.gradle-git-properties' version '2.4.2'
-	id 'com.bmuschko.docker-remote-api' version '9.3.3'
 }
 
 group = 'de.juplo.kafka'
@@ -55,35 +52,6 @@ springBoot {
 	buildInfo()
 }
 
-docker {
-	// Optional: Konfiguriere den Docker-Host, falls nötig
-	// url = 'unix:///var/run/docker.sock' (Standard)
-}
-
-
-def targetDir = file("${projectDir}/target")
-def appJarName = "${project.name}-${project.version}.jar"
-
-// Task zum Bereinigen des `target`-Verzeichnisses bei `clean`
-clean {
-	delete targetDir
-}
-
-// Task zum Kopieren des Haupt-JARs
-task copyJar(type: Copy) {
-	from "$buildDir/libs/${appJarName}"
-	into targetDir
-	dependsOn build
-
-	doFirst {
-		def libs = file("${targetDir}/libs")
-		mkdir(libs)
-	}
-}
-
-// Docker-Task
-task buildDockerImage(type: DockerBuildImage) {
-	inputDir = file('.')
-	images = ["juplo/${project.name}:${project.version}"]
-	dependsOn copyJar
+bootBuildImage {
+	imageName = "juplo/${project.name}:${project.version}"
 }
diff --git a/pom.xml b/pom.xml
index ac72994e..87daecb3 100644
--- a/pom.xml
+++ b/pom.xml
@@ -85,6 +85,11 @@
       <plugin>
         <groupId>org.springframework.boot</groupId>
         <artifactId>spring-boot-maven-plugin</artifactId>
+        <configuration>
+          <image>
+            <name>juplo/${project.artifactId}:${project.version}</name>
+          </image>
+        </configuration>
         <executions>
           <execution>
             <goals>
@@ -97,27 +102,6 @@
         <groupId>pl.project13.maven</groupId>
         <artifactId>git-commit-id-plugin</artifactId>
       </plugin>
-      <plugin>
-        <groupId>io.fabric8</groupId>
-        <artifactId>docker-maven-plugin</artifactId>
-        <version>0.45.0</version>
-        <configuration>
-          <images>
-            <image>
-              <name>juplo/%a:%v</name>
-            </image>
-          </images>
-        </configuration>
-        <executions>
-          <execution>
-             <id>build</id>
-             <phase>package</phase>
-             <goals>
-               <goal>build</goal>
-             </goals>
-          </execution>
-        </executions>
-      </plugin>
     </plugins>
   </build>