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
   

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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
   

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3. Serverless
   @vitalethomas
   

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4. 1. No Servers
   @vitalethomas
   

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5. 1. No Servers Infrastructure
   @vitalethomas
   

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6. Serverless Architectures
   Developers focus on code
   Focus on business logic
   Developer
   Platform
   Infrastructure
   
   Provisioning
   Workload
   
   Management
   Dynamic
   
   Scaling
   @vitalethomas
   

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7. JAR
   Serverless Platforms
   From application artifact to URI
   @vitalethomas
   packaged as
   OCI Image
   deployed on
   deployed on
   

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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
   

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9. thomasvitale.com @vitalethomas
   https://tag-app-delivery.cncf.io/whitepapers/platforms @vitalethomas
   

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10. 2. Scale to Zero
    @vitalethomas
    

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11. 2. Scale to from Zero
    @vitalethomas
    

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12. GraalVM
    @vitalethomas
    

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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
    

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14. Spring Boot 3 and Native Executables
    The downsides of GraalVM
    Longer
    
    Build
    
    Time
    Additional
    con
    fi
    guration
    might be
    needed
    @vitalethomas
    

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15. CRaC
    @vitalethomas
    

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16. 3. Functions
    @vitalethomas
    

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17. Functional Programming Paradigm
    Java Functional Interfaces
    Supplier Function Consumer
    @vitalethomas
    

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18. Function Composition
    Data processing via functions
    uppercase() sentence()
    “I play the PIANO”
    “piano” “PIANO”
    @vitalethomas
    

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19. Spring Cloud Function
    @vitalethomas
    

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20. @vitalethomas
    Spring Cloud Function
    Java Function
    Spring Cloud Function
    

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21. Spring Cloud Function
    Business logic as functions
    Transparent
    
    Type
    
    Conversion
    Function
    
    Arity
    Function
    
    Composition
    Reactive
    
    Support
    JAR
    
    Functions
    @vitalethomas
    

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22. 4. Triggers
    @vitalethomas
    

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23. @vitalethomas
    Spring Cloud Function
    Java Function
    Spring Cloud Function
    

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24. @vitalethomas
    AWS Lambda
    Spring Cloud Function
    Java Function
    AWS Lambda
    
    
    
    org.springframework.cloud
    
    
    spring-cloud-function-adapter-aws
    
    
    
    

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25. @vitalethomas
    Azure Function
    Spring Cloud Function
    Java Function
    Azure Functions
    
    
    
    org.springframework.cloud
    
    
    spring-cloud-function-adapter-azure
    
    
    
    

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26. @vitalethomas
    Google Cloud Function
    Spring Cloud Function
    Java Function
    Google Cloud Functions
    
    
    
    org.springframework.cloud
    
    
    spring-cloud-function-adapter-aws
    
    
    
    

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27. @vitalethomas
    Spring Web
    Spring Cloud Function
    Java Function
    Web Applications
    

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28. 5. Event-driven
    @vitalethomas
    

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29. @vitalethomas
    Spring Cloud Stream
    Spring Cloud Function
    Java Function
    Event-driven Applications
    

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30. Spring Cloud Stream
    @vitalethomas
    

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31. Spring Cloud Stream
    Event-driven applications
    Integration with
    event brokers
    Bindings
    
    with functions
    Publish
    
    Subscribe
    Consumer Groups Partitions
    @vitalethomas
    

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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
    

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33. 6. Developer Experience
    @vitalethomas
    

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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
    

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35. “Friends don’t let friends write Dockerfiles!”
    - Josh Long
    @vitalethomas
    

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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
    

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37. Image
    pack build
    Cloud Native Buildpacks
    From source code to container image
    @vitalethomas
    

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38. Image
    pack build
    gradle bootBuildImage
    Cloud Native Buildpacks
    From source code to container image
    @vitalethomas
    

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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
    

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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
    

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41. Resources
    @vitalethomas
    

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42. github.com/ThomasVitale/serverless-java-with-spring-boot
    

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43. https://github.com/ThomasVitale/awesome-spring
    

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44. Thomas Vitale
    DevBcn
    July 4th, 2023
    Serverless Java
    with Spring Boot
    @vitalethomas
    

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