5分で導入！Failurewall で障害対策 / Failurewall - ScalaMatsuri 2016

ScalaMatsuri 2016 ランチタイム LT の発表資料です。
Scala 標準ライブラリの Future にリトライ機能や Circuit Breaker 機能を導入するライブラリ、Failurewall の紹介です。

https://2016.scalamatsuri.org/
https://github.com/failurewall/failurewall
https://qiita.com/okumin/items/d7a108ea36f3ad2e3882

Transcript

1. ෼Ͱಋೖʂ
   'BJMVSFXBMMͰো֐ରࡦ
   @okumin
   

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2. I am @okumin.
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3. akka-persistence-sql-async
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4. scalacture
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5. ainterface
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6. ґଘγεςϜͱো֐
   

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7. 8FC ΞϓϦ
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8. 8FC ΞϓϦ
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9. Failurewall
   

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10. Failurewall
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    ΤϥʔॲཧΛγϯϓϧʹऔΓѻ͏ͨΊͷϥΠϒϥϦ
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11. ࢖͍ํ
    trait  HTTPClient  {  
       def  get(url:  String):  Future[HTTPResponse]  
    }  
    val  client:  HTTPClient  =  ???  
    //  ԿΒ͔ͷΤϥʔॲཧΛߦ͏Failurewall  
    val  wall:  Failurewall[HTTPResponse,  HTTPResponse]  =  ???  
    val  actual:  Future[HTTPResponse]  =  wall.call  {  
       client.get("https://twitter.com/okumin")  
    }  
    

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12. ༷ʑͳน
    

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13. Retry
    ß 
    Ұ࣌తͳΤϥʔ͸ϦτϥΠʹΑΔϦΧόϦʔ͕༗ޮ
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14. Retry
    val  system  =  ActorSystem("mofu")  
    val  strategy  =  ExponentialBackoffStrategy(  
       minBackoff  =  1.seconds,  
       maxBackoff  =  5.seconds  
    )  
    val  retry  =  AkkaRetryFailurewall[HTTPResponse](  
       maxTrialTimes  =  5,  
       strategy,  
       system.scheduler,  
       system.dispatcher  
    )  
    

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15. Semaphore
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16. Semaphore
    val  executor:  ExecutionContext  =  ???  
    val  semaphore  =  StdSemaphoreFailurewall[HTTPResponse](  
       permits  =  128,  
       executor  
    )  
    

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17. Circuit Breaker
    ß 
    ґଘγεςϜͷ௕Ҿ͘ো֐ʹରॲ
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    $-04&%
    ਖ਼ৗϞʔυ
    )"-'01&/
    ෮چ֬ೝϞʔυ
    01&/
    GBJMGBTUϞʔυ
    

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18. Circuit Breaker
    val  system  =  ActorSystem("mofu")  
    val  circuitBreaker  =  AkkaCircuitBreakerFailurewall[HTTPResponse](  
       system.scheduler,  
       maxFailures  =  16,  
       callTimeout  =  5.seconds,  
       resetTimeout  =  10.seconds,  
       system.dispatcher  
    )  
    

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19. Composable
    ß 
    ΋͏Կ΋ා͘ͳ͍
    val  retry:  Failurewall[HTTPResponse,  HTTPResponse]  =  ???  
    val  semaphore:  Failurewall[HTTPResponse,  HTTPResponse]  =  ???  
    val  circuitBreaker:  Failurewall[HTTPResponse,  HTTPResponse]  =  ???  
    circuitBreaker  compose  semaphore  compose  retry  
    

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20. ੕Λ͍ͩ͘͞
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    ϓϧϦΫ΋େ׻ܴ
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