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

At MiXiT 2018

Transcript

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

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2. ! https://julien.ponge.org/
   " @jponge
   # @jponge
    https://www.mixcloud.com/hclcast/
   

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

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

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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 C”, age=49)
   println(phil)
   phil.name.yo()
   }
   }
   

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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 C”, age=49)
   println(phil)
   phil.name.yo()
   }
   }
   

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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 C”, age=49)
   println(phil)
   phil.name.yo()
   }
   }
   

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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 C”, age=49)
   println(phil)
   phil.name.yo()
   }
   }
   {{{
   Person(name=Philippe C, age=49)
   Philippe -> Yo!
   }}}
   

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9. Reactive?
   (because resources are scarce)
   

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10. 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
    

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11. Application
    

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12. 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");
    }
    }
    

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13. x 1000 =
    %
    

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14. Virtual machines,
    Containers, etc
    

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15. View Slide

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

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17. 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
    

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18. (
    )
    (
    Http server verticle Database client verticle
    
    Event Bus
    +
    )
    “Details for user 1234?”
    “{data}”
    4 instances
    1 instance
    

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19. Events
    Thread
    Event Loop
    (
    (
    (
    (
    (
    

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20. (demo)
    Hello Kotlin + Vert.x
    

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

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23. Kotlin coroutines
    Looks “like” sequential operations
    async/await + Go-style channels
    1/2
    

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24. View Slide

25. View Slide

26. RxJava2 + Kotlin extensions
    Declarative data flows over event sources
    Operators transforming data + event streams
    2/2
    

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27. 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!") }
    )
    }
    

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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!") }
    )
    }
    

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29. 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()
    

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30. Kubernetes?
    (orchestrating containers for you)
    

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

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

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

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

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

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37. Using Kubernetes
    (minikube is your friend)
    

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38. 
    
    
    
    ⚙
    Temperatures services
    Aggregate Alarm
    

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

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40. Outro
    (how was the nap?)
    

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41. 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)
    

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42. 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
    

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43. Lunch at your
    company?
    

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

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