Building a Bank with Go - Golang UK 2015

Large banking systems are incredibly dated, often as a result of a series of mergers between banks, leading to a patchwork of different systems & technologies. As a result, the pace of innovation in the banking industry has slowed to a crawl. At Mondo we are building a new kind of bank, a smart bank that belongs in the 21st century, and we’re building it almost entirely in Go. This talk will cover how we are developing new core banking systems from scratch backed by a microservice based platform written in Go, running across multiple data centres using tools including Docker and Mesos. We also look at why Go is perfectly suited to this, our architectural decisions, common pitfalls to avoid, and lessons learnt when developing high volume, low latency, distributed Go applications.

Transcript

1. BUILDING A BANK
 WITH GO @mattheath Golang UK Conference 2015
2. @mattheath
3. Mondo
6. monoliths traditional dev
8. M
9. M
10. TIME FOR A NEW
 KIND OF BANK?
16. You're doing quite well
20. the majestik møøse
21. the majestik moose
22. sıkısınca
23. sikisinca
26. DATABASE APPLICATION
27. DATABASE APPLICATION
28. DATABASE DATABASES APPLICATION
29. DATABASE DATABASES APPLICATION SEARCH
30. DATABASE DATABASES APPLICATION CACHE SEARCH
31. DATABASE DATABASES APPLICATION CACHE SEARCH CAT GIFS
32. ALL HAIL THE MONOLITH
33. DO NOT WANT
34. DATABASE DATABASES MONOLITH CACHE SEARCH CAT GIFS
35. MONOLITH
38. SINGLE RESPONSIBILITY BOUNDED CONTEXT WELL DEFINED INTERFACES COMPOSABILITY
39. LOAD BALANCER
40. LOAD BALANCER HTTP API & ROUTING LAYER
41. SERVICE TRANSPORT LOAD BALANCER HTTP API & ROUTING LAYER
42. SERVICE SERVICE SERVICE TRANSPORT LOAD BALANCER HTTP API & ROUTING LAYER
43. SERVICE SERVICE SERVICE TRANSPORT DATABASE DATABASE DATABASE LOAD BALANCER HTTP API & ROUTING LAYER
44. SERVICE SERVICE SERVICE TRANSPORT DATABASE DATABASE DATABASE LOAD BALANCER DATACENTRE n HTTP API & ROUTING LAYER
45. SERVICE SERVICE SERVICE TRANSPORT DATABASE DATABASE DATABASE LOAD BALANCER HTTP API & ROUTING LAYER DATACENTRE n
47. gRPC Go KIT Kite go-micro
48. mondough/typhon mondough/mercury
49. LOGIN
 API LOAD BALANCER HTTP API & ROUTING LAYER
50. LOGIN
 API AUTH SERVICE PERMS SERVICE LOAD BALANCER HTTP API & ROUTING LAYER
51. LOGIN
 API AUTH SERVICE PERMS SERVICE LOAD BALANCER HTTP API & ROUTING LAYER ACCOUNT SERVICE
52. LOGIN
 API AUTH SERVICE PERMS SERVICE LOAD BALANCER HTTP API & ROUTING LAYER ACCOUNT SERVICE FEED SERVICE
53. LOAD BALANCER HTTP API & ROUTING LAYER ? ? ? ? ?
54. Logic Handler Storage SERVICE
55. mercury Logic Handler Storage SERVICE
56. mercury Logic Handler Storage libraries SERVICE
57. func main() { srv := service.Init(service.Config{ Name: "service.account", Description: "boop", }) srv.Server().AddEndpoints( handler.Create, handler.Read, handler.List, ) srv.Run() }
58. type Server interface { Name() string AddEndpoints(eps ...Endpoint) RemoveEndpoints(eps ...Endpoint) Endpoint(name string) (Endpoint, bool) Endpoints() []Endpoint Start(trans transport.Transport) error Run(trans transport.Transport) Stop() Middleware() []ServerMiddleware SetMiddleware([]ServerMiddleware) AddMiddleware(ServerMiddleware) }
59. func main() { srv := service.Init(service.Config{ Name: "service.account", Description: "boop", }) srv.Server().AddEndpoints( handler.Create, handler.Read, handler.List, ) srv.Run() }
60. type Endpoint struct { Name string Handler Handler Request interface{} Response interface{} } type Handler func(req mercury.Request) (mercury.Response, error)
61. func main() { srv := service.Init(service.Config{ Name: "service.account", Description: "boop", }) srv.Server().AddEndpoints( handler.Create, handler.Read, handler.List, ) srv.Run() }
62. type Server interface { Name() string AddEndpoints(eps ...Endpoint) RemoveEndpoints(eps ...Endpoint) Endpoint(name string) (Endpoint, bool) Endpoints() []Endpoint Start(trans transport.Transport) error Run(trans transport.Transport) Stop() Middleware() []ServerMiddleware SetMiddleware([]ServerMiddleware) AddMiddleware(ServerMiddleware) }
63. type Transport interface { Tomb() *tomb.Tomb Ready() <-chan struct{} Listen(serviceName string, inboundChan chan<- message.Request) error StopListening(serviceName string) bool Respond(request message.Request, response message.Response) error Send(req message.Request, timeout time.Duration) (message.Response, error) }
64. type Transport interface { Tomb() *tomb.Tomb Ready() <-chan struct{} Listen(serviceName string, inboundChan chan<- message.Request) error StopListening(serviceName string) bool Respond(request message.Request, response message.Response) error Send(req message.Request, timeout time.Duration) (message.Response, error) }
65. api api api.customer api.customer service.customer service.customer
66. type Server interface { Name() string AddEndpoints(eps ...Endpoint) RemoveEndpoints(eps ...Endpoint) Endpoint(name string) (Endpoint, bool) Endpoints() []Endpoint Start(trans transport.Transport) error Run(trans transport.Transport) Stop() Middleware() []ServerMiddleware SetMiddleware([]ServerMiddleware) AddMiddleware(ServerMiddleware) }
67. type ClientMiddleware interface { ProcessClientRequest(req mercury.Request) mercury.Request ProcessClientResponse(rsp mercury.Response, ctx context.Context) mercury.Response ProcessClientError(err *terrors.Error, ctx context.Context) } type ServerMiddleware interface { ProcessServerRequest(req mercury.Request) (mercury.Request, mercury.Response) ProcessServerResponse(rsp mercury.Response, ctx context.Context) mercury.Response }
68. type Context interface { Deadline() (deadline time.Time, ok bool) Done() <-chan struct{} Err() error Value(key interface{}) interface{} }
69. api api api.customer api.customer service.customer service.customer
70. api api api.customer api.customer service.customer service.customer SEND RECV SEND RECV RECV SEND RECV SEND
71. mondough/phosphor mondough/phosphord
72. PhosphorD Service A Trace Library goroutine chan UDP Service B Trace Library goroutine chan UDP PHOSPHOR HOST INSTANCES PUBLISH DASHBOARD AGGREGATION PERSISTANCE
75. mercury Logic Handler Storage libraries SERVICE • PROVISIONING • SERVICE DISCOVERY • CONFIGURATION • MONITORING • AUTHENTICATION/AUTHORISATION • AB TESTING • SELF CONFIGURING CONNECTIVITY 
 TO THIRD-PARTY SERVICES
77. SCRATCH STATIC SSL
78. DEALING WITH 
 COMPLEXITY
79. TESTING
80. LOAD FAILURE DEGRADATION
81. MONITORING
82. type Checker func() (err error, metadata map[string]string)
83. MONITOR YOUR BUSINESS LOGIC
85. DISTRIBUTED
 TRACING
88. SMALL SIMPLE EASY TO LEARN
89. CONCURRENCY NETWORKING INTERFACES
90. DOWNSIDES?
91. STARTING WITH MICROSERVICES?
92. THANKS! @mattheath @getmondo Join our Alpha at getmondo.co.uk! Feedback: joind.in/14960
93. CREDITS ATM: Thomas Hawk
 IBM System/360: IBM Absorbed: Saxbald Photography Orbital Ion Cannon: www.rom.ac Go Gophers: Renee French Control Room: NASA ATM Failure: George Redgrave