Serverless Java with Spring Boot (DevBcn 2023)

Serverless technologies have one clear goal: enabling developers to focus on delivering value while the platform takes care of all the infrastructural concerns. How does Java fit into this space?

This session will demonstrate how to use the native constructs in the Java standard libraries to follow a functional programming paradigm when implementing the business logic of your applications. Functions will be transparently enhanced by Spring Cloud Function, a framework that enriches standard Java to build data pipelines, including features like type conversion and function composition.

Building functions is not enough. We need a strategy to expose and integrate them with the rest of the system. This presentation will show different options to consume Java functions via platforms like Knative, AWS Lambda, Azure Functions, and GCP Functions.

Events are a fundamental part of serverless applications. You’ll see how to use the CloudEvents standard and how to integrate functions with message brokers like RabbitMQ and Kafka. Spring Cloud Stream provides such functionality without requiring any change to your code.

Functions are usually deployed to platforms with autoscaling and scale-to-zero features. GraalVM will be used to compile Java functions as native executables and provides instant startup, instant peak performance, and reduced memory consumption.

Transcript

1. Thomas Vitale DevBcn July 4th, 2023 Serverless Java with Spring Boot @vitalethomas
2. Systematic • Software Engineer and Cloud Architect. • Author of “Cloud Native Spring in Action” (Manning). • OSS contributor (Java, Spring, Cloud Native Technologies) Thomas Vitale thomasvitale.com @vitalethomas
3. Serverless @vitalethomas
4. 1. No Servers @vitalethomas
5. 1. No Servers Infrastructure @vitalethomas
6. Serverless Architectures Developers focus on code Focus on business logic Developer Platform Infrastructure Provisioning Workload Management Dynamic Scaling @vitalethomas
7. JAR Serverless Platforms From application artifact to URI @vitalethomas packaged as OCI Image deployed on deployed on
8. Serverless Platforms From application artifact to URI @vitalethomas aws lambda create-function --function-name Uppercase --zip-file java-function.jar kn service create uppercase --image ghcr.io/thomasvitale/java-function
9. thomasvitale.com @vitalethomas https://tag-app-delivery.cncf.io/whitepapers/platforms @vitalethomas
10. 2. Scale to Zero @vitalethomas
11. 2. Scale to from Zero @vitalethomas
12. GraalVM @vitalethomas
13. Spring Boot 3 and Native Executables The bene fi ts of GraalVM Instant Startup Low Resource Usage Instant Peak Performance @vitalethomas Reduced Surface Attack Compact Packaging
14. Spring Boot 3 and Native Executables The downsides of GraalVM Longer Build Time Additional con fi guration might be needed @vitalethomas
15. CRaC @vitalethomas
16. 3. Functions @vitalethomas
17. Functional Programming Paradigm Java Functional Interfaces Supplier<O> Function<I,O> Consumer<I> @vitalethomas
18. Function Composition Data processing via functions uppercase() sentence() “I play the PIANO” “piano” “PIANO” @vitalethomas
19. Spring Cloud Function @vitalethomas
20. @vitalethomas Spring Cloud Function Java Function Spring Cloud Function
21. Spring Cloud Function Business logic as functions Transparent Type Conversion Function Arity Function Composition Reactive Support JAR Functions @vitalethomas
22. 4. Triggers @vitalethomas
23. @vitalethomas Spring Cloud Function Java Function Spring Cloud Function
24. @vitalethomas AWS Lambda Spring Cloud Function Java Function AWS Lambda <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-function-adapter-aws</artifactId> </dependency>
25. @vitalethomas Azure Function Spring Cloud Function Java Function Azure Functions <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-function-adapter-azure</artifactId> </dependency>
26. @vitalethomas Google Cloud Function Spring Cloud Function Java Function Google Cloud Functions <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-function-adapter-aws</artifactId> </dependency>
27. @vitalethomas Spring Web Spring Cloud Function Java Function Web Applications
28. 5. Event-driven @vitalethomas
29. @vitalethomas Spring Cloud Stream Spring Cloud Function Java Function Event-driven Applications
30. Spring Cloud Stream @vitalethomas
31. Spring Cloud Stream Event-driven applications Integration with event brokers Bindings with functions Publish Subscribe Consumer Groups Partitions @vitalethomas
32. Testcontainers Development and testing with external dependencies OCI containers Run external dependencies as OCI containers Data Layer Tests Ensure environment parity by testing the data layer with the real database Integration Tests Use containers for databases, message queues, and web servers @vitalethomas
33. 6. Developer Experience @vitalethomas
34. Developer Experience “…developer experience could be defined as a means for capturing how developers think and feel about their activities within their working environments, with the assumption that an improvement of the developer experience has positive impacts on characteristics such as sustained team and project performance.” (F. Fagerholm, J. Münch) Developer Experience: Concept and De fi nition (F. Fagerholm, J. Münch) @vitalethomas
35. “Friends don’t let friends write Dockerfiles!” - Josh Long @vitalethomas
36. Dockerfiles “Dockerfiles are easy to write, but the current development guidelines do not produce containers that are repeatable and hardened.” CNCF Software Supply Chain Security Paper https://github.com/cncf/tag-security/tree/main/supply-chain-security @vitalethomas
37. Image pack build Cloud Native Buildpacks From source code to container image @vitalethomas
38. Image pack build gradle bootBuildImage Cloud Native Buildpacks From source code to container image @vitalethomas
39. Deploying Functions with Knative From idea to deployment with autoscaling URL func create Image func deploy Kubernetes Cluster Container Container Container Knative Serving @vitalethomas
40. Deploying Functions with Knative From idea to deployment with autoscaling URL func create Image func deploy Kubernetes Cluster Container Container Container Knative Serving @vitalethomas
41. Resources @vitalethomas
42. github.com/ThomasVitale/serverless-java-with-spring-boot
43. https://github.com/ThomasVitale/awesome-spring
44. Thomas Vitale DevBcn July 4th, 2023 Serverless Java with Spring Boot @vitalethomas