What's new with Spring Boot and Containers?

Spring Boot has established as the most popular framework for Java applications, while containers have become a standard in many aspects of modern software development. Now, how well do they go together? In this session, we’ll explore the most important ways Spring Boot integrates with containers, covering tools and features that simplify building, testing, and running your applications in Docker and Kubernetes. Spring Boot has kept pace with powerful integrations to make working with containers seamless, but are you aware of all (new) integration points and are you able to take full advantage?

This talk will guide you through the entire developer journey covering established integration points as well as updates and new ones: building efficient images with Buildpacks including options like jlink, support for native images, testing in realistic environments with Testcontainers, running locally with recently added Docker Compose feature, and deploying securely in Kubernetes. Additionally we take a glimpse on the new Docker Model runner feature and it’s integration with Spring AI.

Transcript

1. 1 What’s (new) with Spring Boot and Containers Eva Maria Panadero Peris Matthias Haeussler Novatec - now a part of CGI
2. Eva Panadero Senior Backend Engineer, CGI/Novatec Matthias Haeussler Chief Technologist, CGI/Novatec Who we are
3. Why this talk? Some Background … 3
4. History! 4
5. Standard case - Application Container
6. Standard case - Application Container
7. Container to DEVELOP
8. Container to BUILD
9. Container to TEST
10. Container to RUN
11. Container to SCALE
12. Sooo many integrations
13. develop (later) 13
14. build 14
15. 15 FROM ubuntu:24.04 RUN apt update && apt install openjdk-21-jre-headless -y COPY target/simplecode-0.0.1-SNAPSHOT.jar /opt/app.jar CMD ["java","-jar","/opt/app.jar"] Dockerfile (simple)
16. Considerations for structure and size 16
17. Considerations for Java 17
18. Layered Jar 18 FROM eclipse-temurin:21-jre AS builder COPY --from=maven /opt/app/target/simplecode-0.0.1-SNAPSHOT.jar application.jar RUN java -Djarmode=layertools -jar application.jar extract FROM eclipse-temurin:21-jre COPY --from=builder application/dependencies/ ./ COPY --from=builder application/spring-boot-loader/ ./ COPY --from=builder application/snapshot-dependencies/ ./ COPY --from=builder application/application/ ./ ENTRYPOINT ["java","org.springframework.boot.loader.JarLauncher"]
19. jlink and jdeps 19 FROM maven:3-eclipse-temurin-21 AS build RUN --mount=type=cache,target=/root/.m2 mvn package RUN jdeps --ignore-missing-deps -q \ --recursive \ --multi-release 21 \ --print-module-deps \ --class-path 'BOOT-INF/lib/*' \ target/simplecode-0.0.1-SNAPSHOT.jar > deps.info RUN jlink \ --add-modules $(cat deps.info) \ --strip-debug \ --compress 2 \ --no-header-files \ --no-man-pages \ --output /myjre FROM debian:bookworm-slim COPY --from=build /myjre $JAVA_HOME COPY --from=build /usr/src/project/target/simplecode-0.0.1-SNAPSHOT.jar /project/
20. 20 FROM maven:3-eclipse-temurin-21 AS build RUN mkdir /opt/app COPY src /opt/app/src COPY pom.xml /opt/app WORKDIR /opt/app RUN --mount=type=cache,target=/root/.m2 mvn package -DskipTests RUN jar xf target/simplecode-0.0.1-SNAPSHOT.jar RUN jdeps --ignore-missing-deps -q \ --recursive \ --multi-release 21 \ --print-module-deps \ --class-path 'BOOT-INF/lib/*' \ target/simplecode-0.0.1-SNAPSHOT.jar > deps.info RUN jlink \ --add-modules $(cat deps.info) \ --strip-debug \ --compress 2 \ --no-header-files \ --no-man-pages \ --output /myjre FROM eclipse-temurin:21-jre AS extractor RUN mkdir /opt/app WORKDIR /opt/app COPY --from=build /opt/app/target/simplecode-0.0.1-SNAPSHOT.jar application.jar RUN java -Djarmode=layertools -jar application.jar extract FROM ubuntu:jammy ENV JAVA_HOME /opt/java/jdk21 ENV PATH $JAVA_HOME/bin:$PATH COPY --from=build /myjre $JAVA_HOME RUN mkdir /opt/app WORKDIR /opt/app COPY --from=extractor /opt/app/dependencies/ ./ COPY --from=extractor /opt/app/spring-boot-loader/ ./ COPY --from=extractor /opt/app/snapshot-dependencies/ ./ COPY --from=extractor /opt/app/application/ ./ ENTRYPOINT ["java","-XX:+UseParallelGC","-XX:MaxRAMPercentage=75","org.springframework.boot.loader.JarLauncher"]
21. 21 Learnings from optimized Dockerfiles
22. @maeddes | Buildpacks idea 22
23. @maeddes | 23 Flow
24. @maeddes | 24 Flow
25. native images/ GraalVM 25
26. Concept 26
27. GraalVM - Building Types Build options #build JAR file mvn clean package #build Native Image mvn -Pnative native:compile #build JAR inside a Docker Image mvn spring-boot:build-image #build Native Image inside a Docker Image mvn spring-boot:build-image -Pnative -Dspring-boot.build-image.imageName=graalvm-demo:native #build with Pack pack build graalvm-native-images \ --builder paketobuildpacks/builder:tiny \ --env BP_NATIVE_IMAGE=true
28. GraalVM - Run Applications Run options #run JAR file java -jar target/graalvm-0.0.1-SNAPSHOT.jar #run Native Image ./target/graalvm #run JAR inside a Docker Image docker run graalvm:0.0.1-SNAPSHOT #run Native Image inside a Docker Image docker run graalvm-demo:native #run the Buildpack Image docker run graalvm-native-images
29. GraalVM - Setup Adding the dependencies <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>3.4.5</version> </parent> … <plugin> <groupId>org.graalvm.buildtools</groupId> <artifactId>native-maven-plugin</artifactId> </plugin>
30. GraalVM - Setup Spring Boot useful Links: - https://docs.spring.io/spring-boot/reference/packaging/native-image/introducing-graalvm-native-images.html - https://docs.spring.io/spring-boot/how-to/native-image/developing-your-first-application.html - https://www.graalvm.org/latest/getting-started/ - https://buildpacks.io/docs/for-platform-operators/how-to/integrate-ci/pack/
31. testing 31
32. Basic principle
33. Basic principle
34. docker compose 34
35. Integration principle 35
36. testcontainers 36
37. Integration principle 37
38. AI 😇 38
39. Integration principle 39
40. Kubernetes 40
41. Integration principle 41
42. Integration principle 42
43. develop (finally) 43
44. Container to DEVELOP
45. Summary 45
46. Sooo many integrations
47. @maeddes | 47
48. Eva Matthias Häußler Chief Technologist, Novatec @maeddes Thanks for listening!