The document discusses serverless computing and Spring Cloud Function. It describes serverless as being event-driven and allowing dynamic resource utilization and billing per message. Spring Cloud Function allows developing serverless applications using Spring and treating functions as regular Spring beans, while providing adapters for various serverless platforms. It also discusses using Project Reactor to develop reactive serverless functions in Spring.

1. Serverless Spring@david_syer, 2018
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2. Agenda
Serverless and functions
Servless platforms, including Riff
Spring Cloud Function
http://github.com/spring-cloud/spring-cloud-function
http://projectreactor.io/
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3. Serverless
Event driven
Dynamic resource utilization, "scale to zero"
Billing per message
Focus on business logic
Easy integration with platform services
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4. Serverless Use Cases
Web hooks
Background jobs
Glue code (hands-free integration)
CNCF WG Whitepaper
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5. No Code is an Island
Credit: Yan Cui, https://theburningmonk.com
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6. Service Block
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7. Amazon Lambda
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8. Serverless Spring http://localhost:4000/decks/serverless-spring.html
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9. Google Cloud Function
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10. Serverless Spring http://localhost:4000/decks/serverless-spring.html
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11. Microsoft Azure Functions
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12. Serverless Spring http://localhost:4000/decks/serverless-spring.html
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13. Alibaba Function Compute
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14. Serverless Spring http://localhost:4000/decks/serverless-spring.html
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15. Riff
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16. Serverless Spring http://localhost:4000/decks/serverless-spring.html
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17. Serverless Providers
(J) Amazon Lambda
Google Cloud Functions
(J) Azure Function
(J) Alibaba
(J) Riff https://projectriff.io and PFS
(J) IBM OpenWhisk
(J) Oracle Fn
OpenFaaS
Fission
Kubeless
…
(J) = native Java support
Others can run Java, e.g. via custom container or node JRE launcher.
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18. Java Util Function
public interface Function<T, R> {
R apply(T t);
}
public interface Consumer<T> {
void accept(T t);
}
public interface Supplier<T> {
T get();
}
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19. Spring Cloud Function
@SpringBootApplication
public class Application {
@Bean
public Function<String, String> uppercase() {
return value -> value.toUpperCase();
}
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
}
}
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20. Plain Old Functions
package functions;
public class Uppercase implements Function<String, String> {
String apply(String input) {
return input.toUpperCase();
}
}
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21. AWS Cold Starts
Lambda throttles CPU resources when memory is constrained
… also billing is proportional to memory usage
… it’s not that simple
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22. Spring Cloud Function
All the benefits of serverless, but with full access to Spring (dependency injection, integrations,
autoconfiguration) and build tools (testing, continuous delivery, run locally)
For Spring devs: a smaller, more familiar step than using FaaS APIs and UIs natively
For Functionistas: no need to know anything about Spring
Decouple lifecycle of business logic from runtime platform. Run the same code as a web endpoint,
a stream processor, or a task
Uniform programming model across serverless providers, and also able to run standalone
(locally or in a PaaS)
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23. Project Reactor
public abstract class Flux<T> implements Publisher<T> {
...
}
public abstract class Mono<T> implements Publisher<T> {
...
}
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24. Spring Cloud Function
@SpringBootApplication
public class Application {
@Bean
public Function<Flux<String>, Flux<String>> uppercase() {
return flux -> flux
.filter(this::isNotRude)
.map(String::toUpperCase);
}
boolean isNotRude(String word) {
...
}
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
}
}
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25. Spring Cloud Function Adapter
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26. Serverless Spring http://localhost:4000/decks/serverless-spring.html
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27. Spring Cloud Function
Programming model: @Beans of type Function, Consumer and Supplier, with Flux,
Mono, Publisher
1.
Component scan for functions (e.g. execute jar with no dependency on Spring at all)2.
Compile strings which are Java function bodies3.
Bind and invoke from an isolated classloader (JVM packing, platform)4.
Adapters for Spring MVC, Spring Cloud Stream, AWS Lambda, Azure, Riff and other
"serverless" service providers
5.
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28. Learnings
Spring is not slow or "heavy" on its own, classes loaded is important1.
AWS Lambda containers are slow, Azure even more so2.
Functional bean definitions rule for fast startup3.
Functions are glue code anyway - not latency sensitive4.
Scale to Zero5.
Platform services and integration spaghetti6.
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29. Links
Spring Cloud Function: https://github.com/spring-cloud/spring-cloud-function
Riff: https://github.com/projectriff/riff
Spring Boot Thin Launcher: https://github.com/dsyer/spring-boot-thin-launcher
Spring Initializr: http://start.spring.io
Spring Cloud: http://cloud.spring.io
Reactor: http://projectreactor.io
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30. ← →
1 / 23
Go to Slide: Go
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