Why is state important with IoT systems? It's because IoT devices are often noisy chatty little things that frequently communicate to backend systems. In this session, learn how IoT and stateful backends are a perfect match for IoT.

1. How to Build Megaservices
High Throughput Microservices

2. 2
IoT Digital Twins
Low latency, low overhead, high performance
Implemented using
• stateful
• globally unique
• persistent objects (entities)

3. 3

4. 4
Where on Earth (WoE)
Akka Microservices IoT Demo Application
Live Demo

5. WoE Akka Microservice Application
5
woe-sim woe-twin

6. WoE Akka Microservice - Reactive, Elastic, Resilient
6
woe-sim woe-twin
Akka Cluster Akka Cluster

7. WoE Akka Microservice - Reactive, Elastic, Resilient
7
woe-sim woe-twin

8. WoE Akka Microservice - Reactive, Elastic, Resilient
8
woe-sim woe-twin

9. WoE Akka Microservice - Reactive, Elastic, Resilient
woe-sim woe-twin

10. WoE Akka Microservice - Reactive, Elastic, Resilient
10
woe-sim woe-twin

11. 11
“Crop circle” demo Stateful Microservices
Akka Cluster

12. Akka Microservice Development Pattern

20. Akka Microservice

21. Code Review
Examine how WoE microservices implement Akka Microservice development pattern

23. 23
Akka HTTP
Akka gRPC
Akka Projection
Akka Cluster Sharding
Akka Persistence

24. Code Review: Service Edge I/O
WoE Twin IoT telemetry servers for HTTP and gRPC
Akka HTTP
Akka gRPC

26. 26
Akka HTTP
Akka gRPC
Akka Projection
Akka Cluster Sharding
Akka Persistence

27. Code Review: Persistent Objects (Entities)
WoE Twin entities maintain IoT device state
Akka Cluster Sharding
Akka Persistence

29. 29
Akka HTTP
Akka gRPC
Akka Projection
Akka Cluster Sharding
Akka Persistence

33. Code Review: Project events into views
WoE Twin transforms raw events into queryable data
Akka Projection

34. Why CQRS?
Increased Throughput
Reduce Contention
Optimized Data Models
34
Why Akka & CQRS?
Stateful, not Stateless
Hot State, not Cold State
actor

35. About State
Cold State - Stateless
Hot State - Stateful
35

36. 36
Stateless flow

37. 37
Stateless flow
Command cycle 1

38. 38
Stateless flow
Command cycle 1

39. 39
Stateless flow
Command cycle 1

40. 40
Stateless flow
Command cycle 1

41. 41
Stateless flow
Command cycle 1

42. 42
Stateless flow
Command cycle 1

43. 43
Stateless flow
Command cycle 2

44. 44
Stateless flow
Command cycle 2

45. 45
Stateless flow
Command cycle 2

46. 46
Stateless flow
Command cycle 2

47. 47
Stateless flow
Command cycle 2

48. 48
Stateless flow
Command cycle 2

49. 49
Stateless flow
Command cycle 3

50. 50
Stateless flow
Command cycle 3

51. 51
Stateless flow
Command cycle 3

52. 52
Stateless flow
Command cycle 3

53. 53
Stateless flow
Command cycle 3

54. 54
Stateless flow
Command cycle 3

55. About State
Cold State - Stateless
Hot State - Stateful
55

56. 56
Stateful flow

57. 57
Stateful flow
Command cycle 1

58. 58
Stateful flow
Command cycle 1

59. 59
Stateful flow
Command cycle 1

60. 60
Stateful flow
Command cycle 1

61. 61
Stateful flow
Command cycle 1

62. 62
Stateful flow
Command cycle 2

63. 63
Stateful flow
Command cycle 2

64. 64
Stateful flow
Command cycle 2

65. 65
Stateful flow
Command cycle 3

66. 66
Stateful flow
Command cycle 3

67. 67
Stateful flow
Command cycle 3

68. 68
Stateful flow
Command cycle 4

69. 69
Stateful flow
Command cycle 4

70. 70
Stateful flow
Command cycle 4

71. WoE Akka Microservice Application - CQRS
71
woe-sim woe-twin
Journal
(event
log)
Journal
(event
log)
Projection
(view)

72. 72
Where on Earth (WoE)
Akka Microservices IoT Demo Application
Live Demo

73. WoE - Where on Earth Github repos
https://github.com/mckeeh3/woe-sim
https://github.com/mckeeh3/woe-twin
READMEs are WIP
Projects currently under active development
73

74. “Crop Circle” Github repos
https://github.com/mckeeh3/simulator
https://github.com/mckeeh3/visualizer
READMEs are WIP
Projects currently under active development
74

75. 75
Thank You
Hugh McKee
@mckeeh3
https://www.linkedin.com/in/mckeehugh/
hugh.mckee@lightbend.com
Q & A