Netty at Twitter with Finagle

Transcript

1. @TwitterAds | Confidential Evan Meagher (@evanm) 7/28/14 Netty at Twitter

   with Finagle

2. @Twitter 2 Agenda Why and what is Finagle? What does

   it do? What are we working on now?

3. @Twitter 3 What is Finagle?

4. @Twitter 4 An open source, protocol-agnostic, asynchronous RPC library for

   the JVM

5. @Twitter 5 Why did we build Finagle?

6. @Twitter 6 In the beginning…

7. @Twitter 7 Monolithic Rails app MySQL

8. @Twitter 8 Monolithic Rails app MySQL Monolithic Rails app MySQL

   Monolithic Rails app MySQL … Monolithic Rails app MySQL … …

9. @Twitter 9

10. @Twitter 10

11. @Twitter 11 What is Finagle?

12. @Twitter 12 An open source, protocol-agnostic, asynchronous RPC library for

    the JVM

13. @Twitter 13 An open source, protocol-agnostic, asynchronous RPC library for

    the JVM

14. @Twitter 14 An open source, protocol-agnostic, asynchronous RPC library for

    the JVM

15. @Twitter 15 An open source, protocol-agnostic, asynchronous RPC library for

    the JVM

16. @Twitter 16 An open source, protocol-agnostic, asynchronous RPC library for

    the JVM

17. @Twitter 17 What does Finagle do?

18. @Twitter 18 Standardizes the edges in a “boxes and arrows”

    network diagram

19. @Twitter 19 [1] http://monkey.org/~marius/funsrv.pdf

20. @Twitter 20 type Service[Req, Rep] = Req => Future[Rep]

21. @Twitter 21 type Service[Req, Rep] = Req => Future[Rep] Server

    Client Req Future[Rep]

22. @Twitter 22 A contrived example

23. @Twitter 23 val server = new Service[HttpReq, HttpRep] { def

    apply(req: HttpReq): Future[HttpRep] = Future.value(HttpRep(Status.OK, req.body)) } ! Http.serve(":80", server)

24. @Twitter 24 val client: Service[HttpReq, HttpRep] = Http.newService(“twitter.com:80") ! val

    futureResponse: Future[HttpRep] = client(HttpReq(“/")) ! futureResponse map { response => println(response) }

25. @Twitter 25 Now let’s say you need to authenticate requests

26. @Twitter 26 type Service[Req, Rep] = Req => Future[Rep] !

    type Filter[Req, Rep] = (Req, Service[Req, Rep]) => Future[Rep]

27. @Twitter 27 type Service[Req, Rep] = Req => Future[Rep] !

    type Filter[Req, Rep] = (Req, Service[Req, Rep]) => Future[Rep] Filter Filter Server Client

28. @Twitter 28 def isAuthed(req: Req): Boolean val authFilter: Filter[HttpReq, HttpRes]

    = { (req, svc) => if (isAuthed(req)) svc(req) else Future.exception(new AccessDenied) } ! val authedServer: Service[HttpReq, HttpRes] = authFilter andThen server

29. @Twitter 29 val instrumentedServer = authFilter andThen traceRequest andThen recordStats

    andThen server

30. @Twitter 30 What are we working on now?

31. @Twitter 31 Service discovery See the “Names” page on the

    Finagle user guide: http://twitter.github.io/finagle/guide/Names.html ! val client = Http.newService( “zk!myzkhost.mycompany.com:2181!/my/zk/path” )

32. @Twitter 32 Load balancing

33. @Twitter 33 Request multiplexing See the “Protocols” page on the

    Finagle user guide: http://twitter.github.io/finagle/guide/Protocols.html

34. @Twitter 34 Tail-latency optimization

35. @TwitterAds | Confidential Thanks! github.com/twitter/finagle @finagle @evanm