Go and Microservices - NDC London 2018

Presented at NDC London 2018

Transcript

1. 

   Go and
   Microservices
   Matt Heath, Monzo
   

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2. Hi, I’m Matt
   @mattheath
   

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5. A UK banking licence is authorised by the PRA and
   regulated by the PRA and FCA1, allowing deposit-
   taking and balance sheet lending. Once granted,
   it allows firms to passport across Europe, accessing
   This is followed by a “mobilisation” phase during
   which final capital is raised and IT systems are
   completed, before launching to the public.
   We received a UK banking licence in August 2016!
   FEB
   2015
   JAN
   2016
   JAN
   2017
   MAR FEB FEB
   APR MAR MAR APR MAY JUN JUL
   MAY APR
   JUN MAY
   JUL JUN
   AUG JUL
   SEP AUG
   NOV SEP
   DEC NOV DEC
   PRE APPLICATION APPLICATION MOBILISATION LAUNCH
   LICENCE WITH
   RESTRICTIONS
   50K MAX
   DEPOSIT
   WE ARE
   HERE
   A UK banking licence is authorised by the PRA and
   regulated by the PRA and FCA1, allowing deposit-
   taking and balance sheet lending. Once granted,
   it allows firms to passport across Europe, accessing
   This is followed by a “mobilisation” phase during
   which final capital is raised and IT systems are
   completed, before launching to the public.
   We received a UK banking licence in August 2016!
   JAN
   2016
   JAN
   2017
   MAR FEB FEB
   APR MAR MAR APR MAY JUN JUL
   MAY APR
   JUN MAY
   JUL JUN
   AUG JUL
   SEP AUG
   NOV SEP
   DEC NOV DEC
   E APPLICATION APPLICATION MOBILISATION LAUNCH
   LICENCE WITH
   RESTRICTIONS
   WE ARE
   HERE
   AUG

   2017
   JAN

   2016
   Feb

   2015
   APR

   2017
   PREPAID

   LAUNCH
   LICENCE WITH
   RESTRICTIONS
   WE ARE
   HERE
   A UK banking licence is authorised by the PRA and
   regulated by the PRA and FCA1, allowing deposit-
   taking and balance sheet lending. Once granted,
   it allows firms to passport across Europe, accessing
   This is followed by a “mobilisation” phase during
   which final capital is raised and IT systems are
   completed, before launching to the public.
   We received a UK banking licence in August 2016!
   FEB
   2015
   JAN
   2016
   JAN
   2017
   MAR FEB FEB
   APR MAR MAR APR
   MAY APR
   JUN MAY
   JUL JUN
   AUG JUL
   SEP AUG
   NOV SEP
   DEC NOV DEC
   PRE APPLICATION APPLICATION MOBILISATION
   LICENCE WITH
   RESTRICTIONS
   WE ARE
   HERE
   

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17. Simple
    Effective
    Scalable
    

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18. Simplicity
    

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19. Lightweight
    Concurrency
    

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20. Goroutines
    

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21. // Blocking function call
    handleRequest()
    

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22. // Function runs concurrently
    go handleRequest()
    

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23. package main
    func main() {
    go handleRequest()
    // …
    }
    

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24. package main
    func main() {
    go handleRequest()
    // …
    }
    main
    

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25. package main
    func main() {
    go handleRequest()
    // …
    }
    handleRequest
    main
    

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26. "Do not communicate by
    sharing memory; instead, share
    memory by communicating."
    - Effective Go
    

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27. Channels
    

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32. Digging

    Deeper
    

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33. Scheduling
    Goroutines
    

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34. Managing
    Memory
    

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35. Language
    Stability
    

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36. Putting it all
    together
    

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37. But, “microservices”?
    

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38. Low overheads
    

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39. Simple deployment
    

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42. monzo/typhon
    

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43. type Service func(req Request) Response
    

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44. router.GET("/", List)
    router.POST("/", Register)
    router.DELETE("/:id", Deregister)
    

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46. // Handler is your Lambda function handler
    func Handler(request events.APIGatewayProxyRequest)
    (events.APIGatewayProxyResponse, error) {
    ...
    }
    func main() {
    lambda.Start(Handler)
    }
    

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48. ?
    

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49. Application
    

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50. Application
    Database
    

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51. Application
    Database
    

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52. Application
    Databases
    

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53. Application
    Databases
    Search
    

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54. Application
    Databases
    Search
    Caching
    

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55. Application
    Databases
    Search
    Caching
    CAT GIFS
    

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56. APPLICATION
    Application
    

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59. Feb
    2015
    services Jan
    2017
    400
    

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61. ?
    

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62. server
    

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63. server server
    

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64. server server server server server server
    

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65. server server server server server server
    ?
    

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67. server server server server server server
    

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68. server server server server server server
    Kubernetes
    

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69. server server server server server
    kubelet
    

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70. kubelet kubelet kubelet kubelet kubelet kubelet
    

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71. kubelet kubelet kubelet kubelet kubelet kubelet
    Kubernetes Master
    

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72. kubelet kubelet kubelet kubelet kubelet kubelet
    Kubernetes Master
    etcd
    

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73. kubernetes
    

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75. + =
    ❤
    +
    

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76. kubernetes
    service service service service service service
    service
    service
    service service
    

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77. Service
    

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78. Service
    Service
    

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79. Service
    Service
    Transport
    

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80. Service
    Service
    Transport
    Service
    Service
    

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81. Service
    Service
    Transport
    Service
    Service
    Client library
    Server library
    

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82. Service Discovery
    Load Balancing
    Timeouts
    Failure Detection
    Retries
    Rate Limiting
    Circuit Breaking
    Connection Pooling
    Context Propagation
    Metrics and Tracing
    Request Cancellation
    

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83. Service
    Service Service
    Service
    

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84. Service
    Service Service
    Service
    HTTP
    HTTP
    

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85. Service
    Service Service
    Service
    Kubernetes

    Service
    

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86. Service Discovery
    Load Balancing
    Timeouts
    Failure Detection
    Retries
    Rate Limiting
    Circuit Breaking
    Connection Pooling
    Context Propagation
    Metrics and Tracing
    Request Cancellation
    

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87. Service Discovery
    Load Balancing
    Timeouts
    Failure Detection
    Retries
    Rate Limiting
    Circuit Breaking
    Connection Pooling
    Context Propagation
    Metrics and Tracing
    Request Cancellation
    

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88. Service
    Service Service
    Service
    ?
    

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89. Service
    Service Service
    Service
    linkerd
    

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90. Service
    linkerd
    

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91. Service
    linkerd
    service

    discovery
    

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92. Service
    Service Service
    Service
    linkerd
    service

    discovery
    

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93. Service
    Service Service
    Service
    linkerd
    

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94. Service
    Service Service
    Service
    linkerd
    

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95. Service
    Service Service
    Service
    linkerd
    

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96. Service
    Service Service
    Service
    linkerd
    

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97. Load Balancer
    

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98. Load Balancer
    Edge Proxy
    

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99. Load Balancer
    API

    Service
    Edge Proxy
    

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101. /webhooks —-> Webhook API
     

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102. Load Balancer
     Webhook

     API
     Edge Proxy
     

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103. Auth

     Service
     Webhook

     Service
     Load Balancer
     Webhook

     API
     Edge Proxy
     

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104. Auth

     Service
     Webhook

     Service
     Load Balancer
     Webhook

     API
     Database
     Edge Proxy
     

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105. Database
     Auth

     Service
     Webhook

     Service
     Load Balancer
     Webhook

     API
     Database
     Edge Proxy
     

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106. External
     Provider
     Database
     Auth

     Service
     Webhook

     Service
     Load Balancer
     Webhook

     API
     Database
     Edge Proxy
     

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108. CONSTRAIN

     COMPLEXITY
     

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109. SECURITY
     

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110. OPERATIONAL

     EASE
     

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111. WHAT HAVE

     WE LEARNT?
     

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112. Make services
     as small as possible
     

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113. Prefer services
     over libraries
     and shared code
     

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114. Prefer consistency
     in most cases
     

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115. Isolate shared
     infrastructure
     

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116. Onboarding people
     is hard
     

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117. Reduce complexity
     

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118. Monitor EVERYTHING
     

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119. WHAT WOULD WE

     DO DIFFERENTLY?
     

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