Go_Conference_Authmn.pdf

Go Conference Autumn
How to develop "Container/Kubernetes Ready" Go web Application?

モダンなアプリケーション開発においてコンテナ技術の利用はもっとも有効な選択肢の一つである。
また、コンテナ型のプラットフォームの代表であるDockerや、コンテナ・オーケストレーションツールであるKubernetesなどコンテナに関わるプロダクトの多くはGo言語によって開発されている。
しかし、Kubernetesなどのコンテナ環境を前提としたアプリケーション開発ではその他の環境には無い注意点が存在する。このTalkでは、Kubernetes上で行うGo言語アプリケーションの開発におけるTipsを紹介し、よりモダンなアプリケーション開発に必要な知識を共有する。

Transcript

1. How to develop
   “Container/Kubernetes Ready”
   Go Web Application
   2019/10/28 Go Conference Autumn
   ෋Ԭকޗ @tomiokasyogo
   

   View Slide

2. ͸͡Ίʹ..
   

   View Slide

3. ૝ఆௌऀ
   • GoΛ࢖ͬͯΞϓϦέʔγϣϯΛ։ൃͨ͜͠ͱ͕͋Δ
   • ίϯςφΛͳΜͱͳ͘஌ͬͯΔ or ࢖ͬͯΔ
   • Kubernetesʹڵຯ͕͋Δ
   

   View Slide

4. Container
   

   View Slide

5. ίϯςφͱ͸
   

   View Slide

6. https://www.docker.com/resources/what-container
   ίϯςφ͸
   ϗετOS্ͷಠཱ࣮ͨ͠ߦ؀ڥ
   

   View Slide

7. ͦͷ࣮ମ͸
   

   View Slide

8. ίϯςφϥϯλΠϜʹΑͬͯ
   ϗετOSͷϦιʔεΛִ཭ɾ੍ݶ
   ͞Εͨϓϩηε
   

   View Slide

9. ίϯςφؔ࿈ͷϓϩμΫτͷଟ͘
   Ͱ͸Goݴޠ͕࠾༻͞Ε͍ͯΔ
   

   View Slide

10. View Slide

11. Docker and Go
    • Dockerͷ։ൃʹͳͥGo͕બ͹Εͨͷ͔?(2013)
    https://www.slideshare.net/jpetazzo/docker-and-go-why-did-we-decide-to-write-docker-in-go
    1. Static compilation
    2. Neutral
    3. Multi-arch build
    4. Full development
    environment
    etc…
    

    View Slide

12. • ґଘؔ܎ΛҰͭͷόΠφϦʹͰ͖Δ
    • γϯάϧόΠφϦͰಈ࡞Մೳ
    • ޙड़) γεςϜίʔϧΛ؆୯ʹѻ͑Δ
    • etc…
    Go͕ίϯςφͱ૬ੑͷྑ͍ཧ༝
    

    View Slide

13. DockerΛ࢖ͬͯίϯςφԽ

    ͢Δࡍʹ͸DockerfileΛهड़͢Δ
    

    View Slide

14. جຊతͳDockerfile
    ➀
    ➂
    ➁
    ➀ BaseʹͳΔΠϝʔδͷࢦఆ
    ➁ Ϗϧυͷ࣮ߦ
    ➂ ΞϓϦέʔγϣϯͷ࣮ߦ
    

    View Slide

15. Multi-stage build
    ➀
    ➁
    ➂
    ➀ BaseʹͳΔΠϝʔδͷࢦఆ
    ➁ Ϗϧυͷ࣮ߦ
    ➂ Alpine΍DebianͳͲͷΑΓܰྔͳΠϝʔδ
    ➃Ϗϧυͨ͠όΠφϦΛίϐʔ
    ➃
    

    View Slide

16. Dockerͷbest practiceʹؔ͢Δهࣄ
    https://qiita.com/inductor/items/25d5accb80ea606d5c51
    https://www.docker.com/blog/intro-guide-to-dockerfile-best-practices/
    

    View Slide

17. ,VCFSOFUFTš
    

    View Slide

18. Kubernetes
    • ίϯςφ؀ڥͷΦʔέετϨʔγϣϯπʔϧ
    • ίϯςφͷσϓϩΠɺϝϯςφϯεɺεέʔϦϯάΛϚωδϝ
    ϯτͯ͘͠ΕΔ
    • Linux FoundationͷαϒϓϩδΣΫτͰ͋ΔCNCFʹϗετ͞
    Ε͍ͯΔ
    

    View Slide

19. https://www.cncf.io/projects/
    

    View Slide

20. Kubernetesʹొ৔͢Δ֓೦
    • Pod
    • ReplicaSetɺDeployment
    • Service
    ຊ౰͸΋ͬͱͨ͘͞Μ͋Δ͕ɺ্هΛཧղ͢Δ͜ͱ͕࠷ॏཁ
    ೉͍͜͠ͱ͸Kubernetes͕΍ͬͯ͘ΕΔ
    

    View Slide

21. Pod
    • Pod͸ҰͭҎ্ͷίϯςφٴͼετϨʔδͰߏ੒
    • IPΞυϨεͱϙʔτۭؒΛڞ༗ɺಉ͡Pod಺ͳΒ”localhost”
    Ͱૄ௨Մೳ
    https://kubernetes.io/docs/tutorials/kubernetes-basics/explore/explore-intro/
    

    View Slide

22. ➀
    ➂
    ➁
    ➀ Podͷ໊લ
    ➁ ίϯςφ1
    ➂ ίϯςφ2
    

    View Slide

23. ReplicaSet
    • “PodTemplate”ͱݺ͹ΕΔPodͷςϯϓϨʔτΛݩʹPodΛࢦఆ͞
    Εͨ਺ʹௐ੔ɾ؅ཧ͢Δ
    3FQMJDB4FU
    
    1PE
    1PE
    1PE
    Node
    

    View Slide

24. Deployment
    • ReplicaSetΛ؅ཧ͠ɺRolling-Update΍RollBackΛ࣮ݱ
    • imageͷมߋ͕͋ͬͨ࣌ʹ͸৽ͨͳReplicaSetΛੜ੒ɻݹ͍PodΛ৽
    ͍͠PodʹೖΕସ͑Δ
    

    View Slide

25. 3FQMJDB4FU
    
    1PE 1PE
    Podͷߋ৽
    3FQMJDB4FU
    
    %FQMPZNFOU
    1PE 1PE
    v1
    Podͷߋ৽
    

    View Slide

26. 3FQMJDB4FU
    
    1PE 1PE
    v1
    3FQMJDB4FU
    
    1PE 1PE
    v2
    Podͷߋ৽
    ✖
    %FQMPZNFOU
    Node
    ৽͍͠ReplicaSet͕࡞ΒΕΔ
    

    View Slide

27. Service
    • τϥϑΟοΫΛPod΁ϧʔςΟϯά͢Δ
    • Podͷ૿ݮ͕ΞϓϦέʔγϣϯʹӨڹΛ༩͑ͳ͍Α͏ʹந৅Խ
    ͯ͘͠Ε͍ͯΔ
    4FSWJDF
    
    1PE
    
    1PE
    
    1PE
    
    ϦΫΤετ
    

    View Slide

28. KubernetesΛ࢖ͬͯ։ൃ͢Δ
    ࡍɺ͍͔ͭ͘஫ҙ఺͕ଘࡏ͢Δ
    

    View Slide

29. Graceful Start & Shutdown
    

    View Slide

30. Podͷγϟοτμ΢ϯαΠΫϧ
    https://kubernetes.io/docs/concepts/workloads/pods/pod/#termination-of-pods
    

    View Slide

31. ཁ఺ͷΈநग़
    1. PreStop hook͕ઃఆ͞Ε͍ͯΔ৔߹ɺ࠷ॳʹ࣮ߦ͞ΕΔ
    2. SIGTERM͕ίϯςφʹૹΒΕΔ(ෳ਺ͷ৔߹,ॱෆಉ)
    3. Service΍ReplicaSetͷPodϦετ͔Β࡟আ
    4. Grace periodΛ௒͑ͨ৔߹ɺSIGKILL͕ૹΒΕΔ
    Default grace period = 30s (มߋՄ)
    

    View Slide

32. 1. PreStop hook͕ઃఆ͞Ε͍ͯΔ৔߹ɺ࠷ॳʹ࣮ߦ͞ΕΔ
    2. SIGTERM͕ίϯςφʹૹΒΕΔ(ෳ਺ͷ৔߹,ॱෆಉ)
    3. Service΍ReplicaSetͷPodϦετ͔Β࡟আ
    4. Grace periodΛ௒͑ͨ৔߹ɺSIGKILL͕ૹΒΕΔ
    Default grace period = 30s (มߋՄ)
    

    View Slide

33. SIGTERMΛϋϯυϦϯά͠
    αʔόʔͷऴྃॲཧΛߦ͏
    

    View Slide

34. ➀ αʔόʔͷىಈ
    ➁ γάφϧΛड͚औΔνϟωϧΛ࡞੒
    ➂ γάφϧΛड͚औΔ·ͰϒϩοΫɺ
    ड͚औͬͨΒγϟοτμ΢ϯॲཧΛ։࢝
    ➀
    ➂
    ➁
    

    View Slide

35. Dockerར༻࣌ʹ΋ඞཁͳཧ༝
    • “docker stop” => SIGTERM
    • “docker kill “ => SIGKILL
    ͕ૹ৴͞Ε͍ͯΔͨΊɺDockerར༻࣌ʹ΋ϋϯυϦϯάͰ͖Δ
    Α͏ʹ͓͍ͯͨ͠ํ͕ྑ͍
    

    View Slide

36. ཁ఺ͷΈநग़
    1. PreStop hook͕ઃఆ͞Ε͍ͯΔ৔߹ɺ࠷ॳʹ࣮ߦ͞ΕΔ
    2. SIGTERM͕ίϯςφʹૹΒΕΔ(ෳ਺ͷ৔߹,ॱෆಉ)
    3. Service΍ReplicaSetͷPodϦετ͔Β࡟আ
    4. Grace periodΛ௒͑ͨ৔߹ɺSIGKILL͕ૹΒΕΔ
    Default grace period = 30s (มߋՄ)
    ͜ΕΒͷॲཧ͸ඇಉظ
    

    View Slide

37. Podͷ࡟আ͕PodͷService͔Βͷ
    ࡟আΑΓૣ͍ͱɺ֘౰Pod΁ͷϦ
    ΫΤετ͕ࣦഊ͢ΔՄೳੑ͕͋Δ
    

    View Slide

38. ࠶ܝ
    4FSWJDF
    
    1PE
    
    1PE
    
    1PE
    
    ϦΫΤετ
    

    View Slide

39. ͋ΔPodΛ࡟আ͍ͨ͠
    

    View Slide

40. ཧ૝
    4FSWJDF
    
    1PE
    
    1PE
    
    1PE
    
    ϦΫΤετ
    ϧʔςΟϯάઌ͔Β࡟আ
    

    View Slide

41. ཧ૝
    4FSWJDF
    
    1PE
    
    1PE
    
    ϦΫΤετ
    Podͷ࡟আ
    

    View Slide

42. ΋͠ઌʹPod͕ऴྃ͢Δͱ…
    4FSWJDF
    
    1PE
    
    1PE
    
    ϦΫΤετ Podͷ࡟আ
    

    View Slide

43. ΋͠ઌʹPod͕ऴྃ͢Δͱ…
    4FSWJDF
    
    1PE
    
    1PE
    
    ϦΫΤετ
    PodͷIP΁ͷϦΫΤετʹ
    ࣦഊ͢Δ
    

    View Slide

44. Ͳ͏΍ͬͯղܾ͢Δ͔
    

    View Slide

45. preStopHookΛར༻
    

    View Slide

46. preStop hookॲཧΛTERMγάφϧ͕ૹΒΕΔલʹ࣮ߦՄೳ
    

    View Slide

47. • preStop hookͰsleepͤ͞Δ
    • ͜ͷsleepͷؒʹɺγϟοτμ΢ϯ࣌ʹ͖͍ͯΔ
    ϦΫΤετ΋׬ྃͤ͞Δ
    

    View Slide

48. ΑΓৄ͍͠಺༰
    Handling Client Requests Properly with Kubernetes
    https://srcco.de/posts/kubernetes-liveness-probes-are-dangerous.html
    

    View Slide

49. Health-checkͷछྨͱ࣮૷
    

    View Slide

50. Health-check
    Kubernetes͕αϙʔτ͢ΔPodͷHealth-checkʹ͸ɺ
    1. ExecAction: ೚ҙͷίϚϯυͷ࣮ߦ
    2. TCPSocketAction: ࢦఆͨ͠port΁ͷTCPνΣοΫ
    3. HTTPGetAction: ೚ҙͷΤϯυϙΠϯτʹGetϦΫΤετ
    ͕࢖༻Մೳ
    

    View Slide

51. Health-checkͷछྨ
    1. Readiness Probe:
    ɹτϥϑΟοΫ͕ड͚ೖΕΒΕΔঢ়ଶ͔ΛνΣοΫ͢Δ
    ɹࣦഊ͢ΔͱServiceͷϧʔςΟϯάઌ͔Βআ֎͞ΕΔ
    2. Liveness Probe:
    ɹਖ਼͘͠ىಈͰ͖͍ͯΔ͔ΛνΣοΫ͢Δ
    ɹࣦഊͨ͠৔߹͸ίϯςφ͸࠶ߏங͞ΕΔ
    

    View Slide

52. LivenessProbeͱReadinessProbe͕͋Δ͕ɺ
    ·ͣ͸ReadinessProbeͷઃఆΛΦεεϝ͠·͢
    https://srcco.de/posts/kubernetes-liveness-probes-are-dangerous.html
    

    View Slide

53. ➀
    ➂
    ➁
    ➀ ΤϯυϙΠϯτͱportͷࢦఆ
    ➁ ࠷ॳʹϦΫΤετΛૹΔ·Ͱͷ࣌ؒ
    ➂ ϦΫΤετΛૹΔִؒ (default: 10sec)
    

    View Slide

54. • DB΁ͷૄ௨֬ೝ΍ɺΩϟογϡͷϦϩʔυ΋

    Health-checkͷΤϯυϙΠϯτͰ֬ೝ
    • ͙͢ʹαʔόʔ͕Ԡ౴Ͱ͖Δঢ়ଶ͔ΛνΣοΫͰ͖Δ
    

    View Slide

55. ઃఆͷѻ͍
    

    View Slide

56. ίϯςφΛ࢖͏ͱ֤؀ڥ(dev؀ڥɺprd؀ڥʣ
    Ͱಉ͡ΞϓϦέʔγϣϯΛಈ࡞ͤ͞ΒΕΔ
    

    View Slide

57. ͨͩ͠ɺઃఆʹؔͯ͠͸dev΍prdͳͲͷ؀ڥ
    ͝ͱʹҟͳΔ஋͕࢖༻͞ΕΔ΋ͷ΋͋Δ
    ྫ:
    • DBͷ઀ଓઌ
    • ೝূ৘ใͳͲ
    

    View Slide

58. ނʹઃఆ͸ίʔυͱ෼཭͢Δඞཁ͕͋Δ
    ➡؀ڥม਺ͱͯ֨͠ೲ͢Δ
    ͨͩ͠ɺΞϓϦέʔγϣϯ಺෦ͷઃఆ͸ ؚ·ͳ͍
    

    View Slide

59. ؀ڥม਺Λѻ͏ϥΠϒϥϦ
    • https://github.com/kelseyhightower/envconfig
    • https://github.com/caarlos0/env
    • https://github.com/spf13/viper
    ؀ڥม਺Λߏ଄ମ΁Ϛοϐϯάͯ͘͠ΕΔ
    

    View Slide

60. ϩΪϯά
    • ϩά͸σʔλͰ͸ͳ͘ΠϕϯτετϦʔϜͱͯ͠ѻ͏
    • ΞϓϦέʔγϣϯ͸ඪ४ग़ྗʹϩάΛग़͚ͩ͢
    • FluentdͳͲͷϩάίϨΫλʔ͕ͦΕΒͷϩάΛճऩ͢Δ
    https://kubernetes.io/docs/concepts/cluster-administration/logging/
    

    View Slide

61. ϩΪϯά
    • ϩά͸ߏ଄Խ(jsonͳͲʣ͓ͯ͘͜͠ͱΛΦεεϝ͠·͢(ݕࡧ͕͠
    ΍͘͢ͳΔͨΊʣ
    • StackDriverLoggingͳͲΛར༻͢Δ৔߹ɺϩάͷॏཁ౓ϨϕϧͱҰ
    கͤ͞Δ
    

    View Slide

62. uber-go/zap
    https://github.com/uber-go/zap
    • ϩΪϯάͷσϑΝΫτతͳϥΠϒϥϦ
    • ߏ଄Խϩά΍ϩάϨϕϧ΋؆୯ʹઃఆͰ͖ɺύϑΥʔϚϯε΋ଞͷ
    ϥΠϒϥϦͱൺֱͯ͠ྑ͍໛༷
    • ͜Μͳײ͡ͷϩά͕ग़ͤΔ
    

    View Slide

63. Twelve-Factor App
    • Ϟμϯͳ։ൃ؀ڥͰ஫ҙ͢΂͖఺Λ·ͱΊͨ΋ͷ
    • Herokuͷ։ൃऀɺઃཱऀͷAdam WigginsʹΑͬͯఏএ͞Εͨ
    https://12factor.net/ja/
    ʢ೔ຊޠ༁ʣ
    Adam Wiggins
    

    View Slide

64. Twelve-Factor App
    • ґଘؔ܎ͷ໌ࣔԽ
    • ؀ڥ͝ͱͷઃఆͷ੾Γସ͑ʹ؀ڥม਺Λ࢖͏
    • ϩάͷΠϕϯτετϦʔϛϯάԽ
    • ϏϧυɾϦϦʔεͷ෼཭
    ͳͲ
    ͦͷ໊ͷ௨Γ12ͷݪଇ͕ड़΂ΒΕ͍ͯΔ
    

    View Slide

65. Beyond The Twelve-Factor App
    • PivotalࣾͷKevin Hoffman͔Βఏএ͞Εͨ
    • Ϋϥ΢υωΠςΟϒΞϓϦ޲͚ͷTwelve-Factor App
    • Concurrency΍Telemetry͕௥Ճ͞Ε͍ͯΔ
    https://content.pivotal.io/ebooks/beyond-the-12-factor-app
    PDF͕ແྉͰఏڙ͞Ε͍ͯΔ
    

    View Slide

66. ࢀߟهࣄ
    • https://github.com/tommy-sho/gocon-k8s-server <- ࠓճͷൃද༻ͷαϯϓϧϦϙδτϦ
    • https://www.docker.com/resources/what-container
    • https://www.slideshare.net/jpetazzo/docker-and-go-why-did-we-decide-to-write-docker-in-go
    • https://www.docker.com/blog/intro-guide-to-dockerfile-best-practices/
    • https://qiita.com/inductor/items/25d5accb80ea606d5c51
    • https://kubernetes.io/docs/concepts/workloads/pods/pod/
    • https://srcco.de/posts/kubernetes-liveness-probes-are-dangerous.html
    • https://12factor.net/ja/
    • https://freecontent.manning.com/handling-client-requests-properly-with-kubernetes/
    ࢖༻ͨ͠Goper܅ͷΠϝʔδ
    • https://github.com/MariaLetta/free-gophers-pack
    

    View Slide

67. ྑ͍ίϯςφϥΠϑΛ!!
    

    View Slide