The Netflix API has undergone a transformation since its inception in 2008. It has transitioned from being a public API with a generic RESTful interface to a platform for creating highly optimized, device-centric APIs that are critical to delivering the Netflix streaming experience on over 1000 different device types. This talk covers the design principles that shaped the transformation of the API as well as the technology that powers it, enabling rapid user experience iteration and bringing Netflix streaming to almost 38 million subscribers around the world.

1. Transforming the Netflix API
Ben Schmaus, Netflix
October 2013, API World
bschmaus@netflix.com || @schmaus

2. Streaming TV Shows & Movies Globally

3. > 1000 Devices

4. 1/3 of
Internet
at peak

5. Exclusive
Content

6. Almost 38 million
subscribers in over
40 countries

7. Personalization
Engine
User Info
Movie
Metadata
Ratings
Similar
Movies
Instant
Queue
A/B Test
Engine
API

8. Personalization
Engine
User Info
Movie
Metadata
Ratings
Similar
Movies
Instant
Queue
A/B Test
Engine
API
Enable UX
Innovation
Insulate from
Failure

9. It wasn’t always this way

10. Foster
Innovation
from
Outside

11. REST for Easy Interop, Integration
RESTful
API

12. REST for Easy Interop, Integration
RESTful
API
Model resources like users, movies, series,
ratings, etc

13. REST for Easy Interop, Integration
RESTful
API
/catalog/titles
/catalog/titles/movies
/catalog/titles/series
/catalog/titles/series/episodes

14. REST for Easy Interop, Integration
RESTful
API
/users/lists
/users/title_states
/users/ratings

15. Enter
Streaming
Devices

17. Lots of devices, lots of variety
across platforms

19. External apps

20. 1 /apps/{app_id}/config
1 /users/{user_id}
1 /users/{user_id}/queues/instant/available
1 /users/{user_id}/lists
26 /catalog/titles?...

21. Doesn’t include JS, CSS, images,
etc.
1 /apps/{app_id}/config
1 /users/{user_id}
1 /users/{user_id}/queues/instant/available
1 /users/{user_id}/lists
26 /catalog/titles?...

22. Device variance: interaction models

23. Device variance: interaction models
& form factors

24. A/B Tests Add to the Challenge

25. “Bolt on” functionality
expand=@queue_item@title,@box_art_exists,
@short_synopsis,@directors,@cast,@episodes,@formats,
@format_availability,@subtitle_languages,
@languages_and_audio,@maturity_ratings

26. Resource-based API wasn’t scaling

27. Model Resources
/catalog, /users
Model Experiences
/tv/home

28. Reduce network chattiness
Support device optimizations
Enable fast dev iterations

29. GET
/users/{user_id}/lists
apiGateway.getLists(userId)

31. Discrete HTTP requests pay WAN tax repeatedly

33. Single, optimized request; pay WAN tax once

34. Single, optimized request; pay WAN tax once
Client data assembly
logic pushed to server

35. Add server-side scripting capability
Enable independent dev and device
optimization

37. API
Internet /tv/home

38. API
/tv/home
Client Server
Internet

39. API
Application
Client Server
Internet /tv/home

40. API
Client Server
Internet
UI
Teams
Application
/tv/home

41. API
API
Team
Client Server
Internet
UI
Teams
Application
/tv/home

42. API
UI
Teams
API
Team
Mid-tier
Services
Client Server
Internet
Application
/tv/home

43. RxJava Hystrix
API
Team
JavaServiceLayer
Mid-tier
Services
UI
Teams
Client Server
Internet
Application
/tv/home

44. ELB Zuul
Mid-tier
Services
Scriptable
Backend
Scriptable
Backend
+
API Layer

45. https://github.com/Netflix/Hystrix
resilience patterns for distributed
systems
https://github.com/Netflix/RxJava
async, event-based programming
https://github.com/Netflix/zuul
dynamic request routing, realtime
monitoring, resiliency

46. Need well-appointed toolkit

47. Cassandra
upload script.groovy
for /script

48. Cassandra
Cassandra
activate /script
upload script.groovy
for /script

49. Cassandra
Cassandra
activate /script
Cassandra
Scriptable
Backend
load /script
upload script.groovy
for /script

50. Cassandra
Cassandra
activate /script
Cassandra
Scriptable
Backend
load /script
upload script.groovy
for /script
Scriptable
Backend
Device
Client
GET
/script

53. Deployment & Ops

54. Historical & realtime metrics, sort
realtime by error/request rate

55. Distributed grep + tail
2013-05-09.20:38:54 MX 200 us-east-1c i-1824cb73 i-1c61b77f prod NFPS3-001-8G50FJCX...
288404769389848058 90ms api-global.netflix.com GET /tvui/release/470/plus/pathEvaluator -
amazon.ami-id: ami-502eb039
amazon.availability-zone: us-east-1c
amazon.instance-id: i-1824cb73
amazon.instance-type: m2.2xlarge
amazon.local-ipv4: 10.6.213.112
amazon.public-hostname: ec2-54-243-4-69.compute-1.amazonaws.com
amazon.public-ipv4: 54.243.4.69
cookie_esn: NFPS3-001-8G50FJCX...
country: MX
currentTime: 1368131934468
duration-millis: 90
esn: NFPS3-001-8G50FJCX...
geo.city: CIUDADOBREGON
...
$ ./simple_stream.py -f -q 'e["country"]=="MX" && e["esn"]
==~/NFPS3.*/' -r us

56. Go for haystack handing you
the needle

57. Or at least be able to make smaller
haystacks

59. Run 1% of your traffic on the new
code and see how it does

60. API ami-123 API ami-456
2xx
4xx
5xx
latency
busy threads
load
...

61. Confidence score for each AMI based on
comparison of 1000+ metrics

62. Scannable visualization of metric space
More
important
Less
important

63. Your basic red/black push

68. Doing red/black by hand for multiple
clusters across multiple regions is
not fun

69. Automate multi-cluster/region
pushes

70. Automate multi-cluster/region
pushes
Don't forget to
automate
rollbacks, too!

71. $Who, $What, $Where, $When
e.g., "bschmaus, ami-123, Sandbox Canary, 2013-05-06 19:05"
Latest prod change in chat topic

72. Quickly see status of all clusters in a
region

73. API for APIs
Control network interactions
Device optimization
Development agility
Automation & insights

74. Continuously experiment to make
hard things easier

75. bschmaus@netflix.com
@schmaus
Great
Engineers
Wanted!
jobs.netflix.com