The document summarizes a presentation by Mauricio Salatino and Thomas Vitale on using Knative and Spring to build serverless applications and functions. It includes demos of deploying Spring Cloud Functions on Knative to create serverless containers from code and route events between functions. It also describes using Knative Eventing to build an event-driven game architecture with reactive functions.

1. Mauricio Salatino & Thomas Vitale
Spring I/O
May 27th, 2022
Knative and Spring
Bringing back the func
@salaboy @vitalethomas

2. Mauricio Salatino
VMware - Knative OSS
* a.k.a @Salaboy
* Sta
ff
Engineer - Knative Eventing
tech lead for VMware
* Knative OSS core contributor
* Passionate about Functions,
Platforms, Open Source and
Kubernetes
salaboy.com

3. Systematic
* Software Architect at
Systematic, Denmark.
* Author of “Cloud Native Spring
in Action” (Manning).
* Spring Security and Spring
Cloud contributor.
Thomas Vitale
thomasvitale.com @vitalethomas

4. Quiz Game
thomasvitale.com @vitalethomas
@salaboy @vitalethomas
Building applications using functions

5. Serverless
@salaboy @vitalethomas

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

7. Knative Serving
Serverless Containers on Kubernetes
Developer-friendly
abstractions
From code to URL
Autoscaling
Scaling to zero
Progressive
Rollouts
Request-driven
Event-driven
@salaboy @vitalethomas
Cloud agnostic

8. buildpacks.io

9. Demo
thomasvitale.com @vitalethomas
@salaboy @vitalethomas
Knative Serving and Buildpacks - From code to URL

10. Platform v1 - Serverless experience
From containers to deployment with autoscaling
@salaboy @vitalethomas
Image
pack kn
URL
Kubernetes Cluster
Container
Container
Container
Knative
Serving

11. Functions
@salaboy @vitalethomas

12. Demo
thomasvitale.com @vitalethomas
@salaboy @vitalethomas
Knative Functions - From code to URL

13. Functions
Functional programming model
Triggered by
requests or events
Stateless Smaller scope
Cold start Cost optimization
@salaboy @vitalethomas

14. Functions Patterns
Topologies for functional programming
@salaboy @vitalethomas
Asynchronous
processing
Event-based
Data stream
via chained
functions
Synchronous
Asynchronous
Fire and Forget
Request/
Response
Request/
Response (State)

15. More on Knative Functions
In active development, join the community!
External templates
repository
Run locally with
func run
On-cluster build,
no Docker required
Roadmap to 1.0 GA
@salaboy @vitalethomas
Works with multiple
languages and
frameworks

16. Platform v2 - Polyglot Functions
From idea to deployment with autoscaling
@salaboy @vitalethomas
URL
func create
Image
func deploy
Kubernetes Cluster
Container
Container
Container
Knative
Serving

17. Functions with Spring
@salaboy @vitalethomas

18. Spring Native
Native executables with GraalVM
Slower
Heavier
Build
Instant
Startup
Reduced
Memory
Consumption
Instant
Peak
Performance
Fewer
Runtime
Optimizations
@salaboy @vitalethomas

19. Functional Programming Paradigm
Java 8 Functional Interfaces
Supplier<O> Function<I,O> Consumer<I>
@salaboy @vitalethomas

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

21. Demo
thomasvitale.com @vitalethomas
@salaboy @vitalethomas
Knative Functions - From code to URL

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

23. Spring Cloud Function
Deployment and integrations
Knative CloudEvents RSocket
Azure
Functions
Google Cloud
Functions
AWS
Lambda
@salaboy @vitalethomas

24. Events
@salaboy @vitalethomas

25. CloudEvents
Interoperability and standardization
Metadata
Data
Id
Source
Type
Payload
JSON
AMQP
Kafka
MQTT
@salaboy @vitalethomas

26. Spring Cloud Functions Routing
Routing Events to functions
A()
CloudEvent
B()
C()
Router
[Ce-Type]

27. Knative Eventing
Event routing and triggers
Developer-friendly
abstractions
Event-driven
architectures
Event routing
Polyglot support
with CloudEvents
Pluggable
@salaboy @vitalethomas
Cloud agnostic

28. Platform v3 - Knative Eventing
Event-driven and reactive functions
@salaboy @vitalethomas
URL
func create
+ trigger
Image
func deploy
Kubernetes Cluster
Container Container
Knative
Serving &
Eventing
Knative Broker
Knative Event Sources
Trigger A Trigger B

29. Game - Architecture
@salaboy @vitalethomas

30. Kubernetes Cluster
Game - Functions
Synchronous functions with Knative
<Client Side>
React Application
<Orchestrator>
Game FrontEnd
<Function>
Start Game
<Function>
Level X
…
<Function>
Get LeaderB
Redis
(State)
HTTP
SYNC
<Function>
Level 1
…

31. Game - Eventing
Knative Eventing, CloudEvents & RSocket
Kubernetes Cluster
<Client Side>
React Application
<Orchestrator>
Game FrontEnd
<Function>
Level X
…
Redis
HTTP SYNC
Broker
Trigger
Score
CloudEvent
RSocket
GameScore
CloudEvent
Trigger
Another
Function

32. thomasvitale.com @vitalethomas
@salaboy @vitalethomas
tinyurl.com/springio-func

33. Discount codes
Manning
• 45% discount code, valid for
all products in all format
• ctwspringio22
• manning.com

34. Resources
Source code
• Learn more about the game:
• https://github.com/salaboy/from-monolith-to-k8s/tree/main/game
• Deploy the game on Kubernetes:
• https://github.com/ThomasVitale/eventing-game
• Spring Cloud Function samples:
• https://github.com/ThomasVitale/springio-2022-knative-spring-func