This is a talk about the evolution of Gilt's SOA stack, from Ruby to type-unsafe Java with hashmaps, to a full-blown typesafe, futures-based Scala API.

1. Fast but Not Loose:
Typesafe Clients in a
Distributed Service Architecture,
a retrospective
#gotocon #gotoaar #gilttech
Eric Bowman
VP Architecture @ Gilt Groupe
Monday, September 30, 13
@ebowman
ebowman@gilt.com

2. Monday, September 30, 13

3. Monday, September 30, 13

4. •Scala
•Play
•PostgreSQL
•MongoDB
•Voldemort
•Kafka
•Aster Data
•Mahout
•Jersey
•SBT
•Docker
•Continuous Delivery
Microservices
Monday, September 30, 13

5. http://upload.wikimedia.org/wikipedia/commons/1/16/Ruby_on_Rails-logo.png
http://wiki.postgresql.org/wiki/File:PostgreSQL_logo.3colors.svg
Monday, September 30, 13

6. http://logonoid.com/images/thumbs/christian-louboutin-logo.jpg
Monday, September 30, 13

7. http://data.iluxdb.com/data/christian-louboutin-daffodile-160mm-python-masai-1130127cm09_001.jpg?dd80c0
Monday, September 30, 13

8. http://upload.wikimedia.org/wikipedia/commons/7/79/Operation_Upshot-Knothole_-_Badger_001.jpg
Monday, September 30, 13

9. Monday, September 30, 13

10. Monday, September 30, 13

11. Monday, September 30, 13

12. Monday, September 30, 13

13. Monday, September 30, 13

14. Monday, September 30, 13

15. Monday, September 30, 13

16. http://blog.verwilst.be/wp-content/uploads/2008/12/java.gif
Monday, September 30, 13

17. swift
user_service
Monday, September 30, 13
order_service
payment_service
product_service
cart_service
pagegen

18. http://megmurph.com/wp-content/uploads/2013/03/success-1.jpg
Monday, September 30, 13

19. Service X
Front End
Service Y
Service Z
Monday, September 30, 13

20. Service X
Front End
Service Y
Service Z
Monday, September 30, 13

21. Content from Service X
Service X
Service Y
Content from Service Y
Service Z
Monday, September 30, 13
Content from Z
Front End

22. Front-End Tier
Service Tier
Data Tier
Monday, September 30, 13

23. Front-End Tier
Service Tier
Data Tier
Monday, September 30, 13
Caching
Light Computation
Orchestration

24. Front-End Tier
Caching
Light Computation
Orchestration
Service Tier
Caching
Heavier Computation
Separation of Concerns
Data Tier
Monday, September 30, 13

25. Front-End Tier
Service Tier
Caching
Heavier Computation
Separation of Concerns
Data Tier
Monday, September 30, 13
Caching
Light Computation
Orchestration
Data Access
(Disk/SSD/RAM)

26. Front-End Tier
Caching
Light Computation
Orchestration
Service Tier
Caching
Heavier Computation
Separation of Concerns
Data Tier
Data Access
(Disk/SSD/RAM)
•Runtime Temperature
•Development Temperature
Monday, September 30, 13

27. Service
Data Source
JDBC ➾ HashMap ➾
JSON
Front End
JSON ➾ HashMap ➾
JSON
Javascript
Application
http://gilt.com
Monday, September 30, 13

28. Service
Data Source
JDBC ➾ HashMap ➾
JSON
Front End
JSON ➾ HashMap ➾
JSON
Javascript
Application
http://gilt.com
Chaos Grows Quickly
Monday, September 30, 13

29. Front End
Service
Data
Source
JDBC ➾ HashMap ➾ JSON
JSON ➾ HashMap ➾
JSON
Service
Data
Source
JDBC ➾ HashMap ➾ JSON
JSON ➾ HashMap ➾
JSON
Javascript
Application
http://gilt.com
Service
Data
Source
Monday, September 30, 13
JDBC ➾ HashMap ➾ JSON
JSON ➾ HashMap ➾
JSON

30. Front End
Service
Data
Source
Service
JSON ➾ HashMap ➾
JSON
JDBC ➾ HashMap ➾ JSON
JSON ➾ HashMap ➾ JSON
Service
JSON ➾ HashMap ➾ JSON
Data
Source
JSON ➾ HashMap ➾
JSON
Javascript
Application
JDBC ➾ HashMap ➾ JSON
http://gilt.com
Service
Data
Source
Monday, September 30, 13
JDBC ➾ HashMap ➾ JSON
JSON ➾ HashMap ➾
JSON

31. http://www.recruitmenttakeout.com/wp-content/uploads/2013/04/brian.png
Monday, September 30, 13

32. •Fast
•Service Decomposition
•Implicit core model was good
Monday, September 30, 13

33. •Org Scaling
•APIs
•Implicit core model was ... implicit
Monday, September 30, 13

34. A data model and
APIs for services
Monday, September 30, 13

35. A data model and
APIs for services
(aka, RPC)
Monday, September 30, 13

36. core
service
core
service
core
service
core
service
Legacy
http://git-scm.com/images/logos/downloads/Git-Logo-2Color.png
Monday, September 30, 13

37. core
service
commons.jar
core
service
core
service
core
service
Legacy
http://git-scm.com/images/logos/downloads/Git-Logo-2Color.png
Monday, September 30, 13
core clients
core data
model
async client
framework
Greenfield

38. core
service
commons.jar
core
service
core
service
core
service
Legacy
http://git-scm.com/images/logos/downloads/Git-Logo-2Color.png
Monday, September 30, 13
core clients
core data
model
async client
framework
Greenfield
•Users
•Sales
•Products
•Skus
•Assets
•Targeting
•Auth

39. service
client
core
Monday, September 30, 13

40. service
client
core
Monday, September 30, 13
•RESTful
•Scala clients
•All APIs futures-based
•Case class schema

41. service
client
core
Compile/Runtime
Dependency
client
core
Monday, September 30, 13
service

42. Consumer
Client
Core
“Embassy Soil”
Monday, September 30, 13
Service
Core

43. Consumer
Client
Core
Service
Core
•Easy functional testing
•Service response capture
•Test linking
•Upgradable
•Emergent Regression
•Automated upgrades
•Compile farmers
Monday, September 30, 13

44. Consumer
Client
Core
Monday, September 30, 13
Service
Core

45. Consumer
Client
Core
Service
Core
•Environment ⊕ Config
•Live updates
•Indirection
•Circuit Breaker
Monday, September 30, 13

46. Monday, September 30, 13

47. “All of this is
completely wrong.”*
*Not an actual quote
Monday, September 30, 13

48. 1.The network is reliable
2.Latency is zero
3.Bandwidth is infinite
4.The network is secure
5.Topology doesn't change
6.There is one administrator
7.Transport cost is zero
8.The network is homogeneous
https://blogs.oracle.com/jag/resource/Fallacies.html
Monday, September 30, 13

49. 1.The network is reliable
https://blogs.oracle.com/jag/resource/Fallacies.html
Monday, September 30, 13

50. d
e
v
1.The network islreliable
o
s
e
R
https://blogs.oracle.com/jag/resource/Fallacies.html
Monday, September 30, 13

51. 2.Latency is zero
https://blogs.oracle.com/jag/resource/Fallacies.html
Monday, September 30, 13

52. d
e
v
l
2.Latency is zero
o
s
e
R
https://blogs.oracle.com/jag/resource/Fallacies.html
Monday, September 30, 13

53. 3.Bandwidth is infinite
https://blogs.oracle.com/jag/resource/Fallacies.html
Monday, September 30, 13

54. d
e
v
l
3.Bandwidth is infinite
o
s
e
R
https://blogs.oracle.com/jag/resource/Fallacies.html
Monday, September 30, 13

55. 4.The network is secure
https://blogs.oracle.com/jag/resource/Fallacies.html
Monday, September 30, 13

56. d
e
v
4.The network islsecure
o
s
e
R
https://blogs.oracle.com/jag/resource/Fallacies.html
Monday, September 30, 13

57. 5.Topology doesn't change
https://blogs.oracle.com/jag/resource/Fallacies.html
Monday, September 30, 13

58. d
e
v change
l
5.Topology doesn't
o
s
e
R
https://blogs.oracle.com/jag/resource/Fallacies.html
Monday, September 30, 13

59. 6.There is one administrator
https://blogs.oracle.com/jag/resource/Fallacies.html
Monday, September 30, 13

60. d
e
v
l
6.There is one administrator
o
s
e
R
https://blogs.oracle.com/jag/resource/Fallacies.html
Monday, September 30, 13

61. 7.Transport cost is zero
https://blogs.oracle.com/jag/resource/Fallacies.html
Monday, September 30, 13

62. d
e
v zero
7.Transport costlis
o
s
e
R
https://blogs.oracle.com/jag/resource/Fallacies.html
Monday, September 30, 13

63. 8.The network is homogeneous
https://blogs.oracle.com/jag/resource/Fallacies.html
Monday, September 30, 13

64. d
e
v
8.The network islhomogeneous
o
s
e
R
https://blogs.oracle.com/jag/resource/Fallacies.html
Monday, September 30, 13

65. “Still Wrong.”*
*Possibly an actual quote
Monday, September 30, 13

66. Convenience Over
Correctness
http://steve.vinoski.net/blog/2008/07/01/convenience-over-correctness/
Monday, September 30, 13

67. Public Data Model
Client Layer
Client Data Model
Client Backend
Client/Server Serialization
Model
Service Frontend
Service Model
Service Backend
Database Model
Database
Monday, September 30, 13

68. Public Data Model
Client Layer
Client Data Model
Client Backend
Client/Server Serialization
Model
Service Frontend
Service Model
Service Backend
Database Model
Database
Monday, September 30, 13
•So many models
•Corners are cut
•Typesafe helps
•Conflation?
•Just the data

69. Public Data Model
Client Layer
Client Data Model
Client Backend
Client/Server Serialization
Model
Service Frontend
Service Model
Service Backend
Database Model
•So many models
•Corners are cut
•Typesafe helps
•Conflation?
•Just the data
Database
“Works in Practice for some use cases”
Monday, September 30, 13

70. Public Data Model
Client Layer
Client Data Model
Client Backend
Client/Server Serialization
Model
Service Frontend
Service Model
Service Backend
Database Model
•So many models
•Corners are cut
•Typesafe helps
•Conflation?
•Just the data
Database
“Works in Practice for some use cases”
“No free silver bullet lunches.”
Monday, September 30, 13

71. However...
Monday, September 30, 13

72. However...
•No machine generated stubs
•Embassy-Oriented Programming
•Lots of indirection
•Type-system support for failures
Monday, September 30, 13

73. What Actually Sucks
about RPC:
Monday, September 30, 13

74. What Actually Sucks
about RPC:
•Remote objects
•Failures
•Idempotency
Monday, September 30, 13

75. Ignoring all that
was Too Easy.
Monday, September 30, 13

76. Monday, September 30, 13

77. Batch Jobs
Monday, September 30, 13

78. 1.The network is reliable
2.Latency is zero
3.Bandwidth is infinite
4.The network is secure
5.Topology doesn't change
6.There is one administrator
7.Transport cost is zero
8.The network is homogeneous
Monday, September 30, 13

79. Law of Instrument
Monday, September 30, 13

80. Pulling data.
Monday, September 30, 13

81. Pushing code.
Monday, September 30, 13

82. SOA, Reloaded
Monday, September 30, 13

83. SOA, Reloaded
•CRUD
•Event Streams
•Batch Processing
•Lambda Architecture
•CQRS
Monday, September 30, 13

84. Client
Service
DB
Monday, September 30, 13

85. Client
Clickstream
data
Service
Fast
Storage
DB
Kafka
CEP
Batch Jobs
Monday, September 30, 13
Data
Warehouse

86. http://tech.gilt.com
join us.
new york & dublin
Monday, September 30, 13