Démystifier le réactif et l'orchestration de services avec Vert.x, Kubernetes et Kotlin

Transcript

1. Démystifier le réactif et l'orchestration de
   services avec Vert.x, Kubernetes et Kotlin
   

   View Slide

2. Julien Ponge
   Maitre de Conférences
   “Delegated consultant to Red Hat” on Vert.x
   Eclipse Golo + extensive F/OSS background
   ! https://julien.ponge.org/
   " @jponge
   # @jponge
    https://www.mixcloud.com/hclcast/
   

   View Slide

3. “No to average expertise on
   any of these technologies”
   ! "
   (or async)
   

   View Slide

4. Kotlin?
   (1 slide to be an expert)
   

   View Slide

5. data class Person(val name: String, val age: Int)
   fun String.yo() {
   println("$this -> Yo!")
   }
   fun wrap(block: () -> Unit) {
   println("{{{")
   block()
   println("}}}")
   }
   fun main(args: Array) {
   wrap {
   val phil = Person(name="Philippe", age=45)
   println(phil)
   phil.name.yo()
   }
   }
   

   View Slide

6. data class Person(val name: String, val age: Int)
   fun String.yo() {
   println("$this -> Yo!")
   }
   fun wrap(block: () -> Unit) {
   println("{{{")
   block()
   println("}}}")
   }
   fun main(args: Array) {
   wrap {
   val phil = Person(name="Philippe", age=45)
   println(phil)
   phil.name.yo()
   }
   }
   

   View Slide

7. data class Person(val name: String, val age: Int)
   fun String.yo() {
   println("$this -> Yo!")
   }
   fun wrap(block: () -> Unit) {
   println("{{{")
   block()
   println("}}}")
   }
   fun main(args: Array) {
   wrap {
   val phil = Person(name="Philippe", age=45)
   println(phil)
   phil.name.yo()
   }
   }
   

   View Slide

8. data class Person(val name: String, val age: Int)
   fun String.yo() {
   println("$this -> Yo!")
   }
   fun wrap(block: () -> Unit) {
   println("{{{")
   block()
   println("}}}")
   }
   fun main(args: Array) {
   wrap {
   val phil = Person(name="Philippe", age=45)
   println(phil)
   phil.name.yo()
   }
   }
   {{{
   Person(name=Philippe, age=45)
   Philippe -> Yo!
   }}}
   

   View Slide

9. Reactive?
   (because resources are scarce)
   

   View Slide

10. View Slide

11. Application
    

    View Slide

12. Reactive
    systems
    Reactive
    streams
    Reactive
    programming
    Reactive
    “Responding to stimuli”
    Manifesto, Actor, Messages
    Resilience, Elasticity, Scalability,
    Asynchronous, non-blocking
    Data flow
    Back-pressure
    Non-blocking
    Data flow
    Events, Observable
    Spreadsheets
    Akka, Vert.x Akka Streams, RxJava,
    Reactor, Vert.x
    Reactor, Reactive Spring,
    RxJava, Vert.x
    

    View Slide

13. while (isRunning) {
    String line = bufferedReader.readLine();
    switch (line.substring(0, 4)) {
    case "ECHO":
    bufferedWriter.write(line);
    break
    // ...
    // other cases ( ...)
    // ...
    default:
    bufferedWriter.write("UNKW Unknown command");
    }
    }
    

    View Slide

14. x 1000 =
    %
    

    View Slide

15. Virtual machines,
    Containers, etc
    

    View Slide

16. View Slide

17. Vert.x?
    (async all the things!)
    

    View Slide

18. Eclipse Vert.x
    Open source project started in 2012
    Eclipse / Apache licensing
    A toolkit for building reactive applications for the JVM
    7K ⋆ on '
    Built on top of
    ! https://vertx.io
    " @vertx_project
    

    View Slide

19. (
    )
    (
    Http server verticle Database client verticle
    
    Event Bus
    +
    )
    “Details for user 1234?”
    “{data}”
    4 instances
    1 instance
    

    View Slide

20. Events
    Thread
    Event Loop
    

    View Slide

21. 
    Verticles
    (
    (
    (
    public class SomeVerticle extends AbstractVerticle {
    @Override
    public void start() throws Exception { }
    @Override
    public void stop() throws Exception { }
    }
    class SomeVerticle : AbstractVerticle() {
    override fun start() { }
    override fun stop() { }
    }
    exports.vertxStart = function() { }
    exports.vertxStop = function() { }
    

    View Slide

22. (demo)
    Hello Kotlin + Vert.x
    

    View Slide

23. View Slide

24. Async is hard
    
    (callback hell is just one facet)
    

    View Slide

25. Kotlin coroutines
    Looks “like” sequential operations
    async/await, Go-style channels
    

    View Slide

26. View Slide

27. RxJava2 + Kotlin extensions
    Declarative data flows over event sources
    Operators transforming data + event streams
    

    View Slide

28. fun main(args: Array) {
    val rand = Random()
    val o1 = Observable
    .fromCallable(rand ::nextInt)
    .repeat()
    .take(500, TimeUnit.MILLISECONDS)
    .filter { it > 0 }
    .filter { it % 2 == 0 }
    .map { "[${it}]" }
    val o2 = Observable.fromIterable(1 ..Long.MAX_VALUE)
    Observables
    .zip(o1, o2) { n, id -> "${id} -> ${n}" }
    .subscribeBy(
    onNext = logger ::info,
    onError = { logger.error("Oh?") },
    onComplete = { logger.info("Done!") }
    )
    }
    “id -> [n]”
    zip()
    

    View Slide

29. Kubernetes?
    (orchestrating containers for you)
    

    View Slide

30. https://cloud.google.com/kubernetes-engine/kubernetes-comic
    

    View Slide

31. View Slide

32. https://cloud.google.com/kubernetes-engine/kubernetes-comic
    

    View Slide

33. https://cloud.google.com/kubernetes-engine/kubernetes-comic
    

    View Slide

34. Pod
    Pod
    Pod
    Pod
    Pod
    Pod
    Pod Pod
    Node
    Node
    Master(s)
    

    View Slide

35. Same host
    Same network
    Same namespace
    Same volumes
    Same secrets
    Pod
    Container
    Container
    Container
    

    View Slide

36. Container
    Container
    Container
    Pod replicas & scaling
    Readiness probes
    Liveness probes
    Restart policy
    Rolling upgrades
    (…)
    

    View Slide

37. Using Kubernetes
    (minikube is your friend)
    

    View Slide

38. 
    
    
    
    ⚙
    Temperatures services
    Aggregate Alarm
    

    View Slide

39. 
    Vert.x callbacks
    Coroutines, liveness
    RxKotlin
    Discovery
    RxKotlin, SockJS event bus bridge, VueJS, MongoDB
    

    View Slide

40. (demo)
    Kubernetes (minikube)
    https://github.com/jponge/demo-vertx-kotlin-rxjava2-kubernetes
    

    View Slide

41. Outro
    (how was the nap?)
    

    View Slide

42. Unified end-to-end reactive model + ecosystem
    (not just APIs…)
    For all kinds of distributed applications
    (even the small-scale ones)
    Flexible toolkit, not a framework
    (your needs, your call)
    

    View Slide

43. https: //youtu.be/ZkWsilpiSqw
    - Applications réactives avec Eclipse Vert.x
    . Building Reactive Microservices in Java
    https: //goo.gl/ep6yB9
    . Guide to async programming with Vert.x for Java developers
    https: //goo.gl/AcWW3A
    

    View Slide

44. Q&A
    ! https://julien.ponge.org/
    " @jponge
    # @jponge
     https://www.mixcloud.com/hclcast/
    

    View Slide