Video and slides synchronized, mp3 and slide download available at URL http://bit.ly/29vYBQB. Katharina Probst talks about the situations in which server-side scripting is a good solution for applications. She describes Netflix’s first approach, which uses Groovy scripts. She details how the scripts are uploaded and can make use of shared modules and then dives into a new approach that isolates the scripts into their own containers without compromising the original goals. Filmed at qconnewyork.com. Katharina Probst is Engineering Manager at Netflix, where she leads the API team and helps bring Netflix streaming to millions of people around the world. Prior to joining Netflix, she was in the cloud computing team at Google, where she saw cloud computing from the provider side.

1. The Netflix API Platform for
Server-Side Scripting

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Watch the video with slide
synchronization on InfoQ.com!
https://www.infoq.com/presentations/
netflix-groovy-scripting

3. Presented at QCon New York
www.qconnewyork.com
Purpose of QCon
- to empower software development by facilitating the spread of
knowledge and innovation
Strategy
- practitioner-driven conference designed for YOU: influencers of
change and innovation in your teams
- speakers and topics driving the evolution and innovation
- connecting and catalyzing the influencers and innovators
Highlights
- attended by more than 12,000 delegates since 2007
- held in 9 cities worldwide

4. Problem identified: new
servers aren’t coming up
healthy!
Ugh! There’s a problem.
Errors from API are up.

5. Stream starts per second more and
more off.
Expected value
Actual value

6. Finally root-caused!
Now restarting all
unhealthy servers.
Back to
normal!

7. Stream starts per
second also back to
normal.
Expected value
Actual value

11. Js
(mostly)
java
Client A
Client B
Client C
Client A
Client Y
Client Z
...
...
Netflix
Microservices
Network
boundary
API Server JVM

15. Js
(mostly)
java
Client A
Client B
Client C
Client A
Client Y
Client Z
...
...
Netflix
Microservices
scripts
scripts
scripts
scripts
...
scripts
scripts
scripts
scripts
Network
boundary
API Server JVM
~700 active
groovy

16. [...]
Device1VideoCommon. formatKidsSeason (apiRequest,[...], imageUrl)
[...]
[...]
Device2Common. formatAllSeasons([...])
[...]
[...]
dataPublishingService.getShowFeedbackBuilder(user, video)
[...]

18. n+3
i+4
i+1
i+2i+3
i
n+2
n+1
n
k+1
k j
j+1
l

21. Js
(mostly)
java
Client A
Client B
Client C
Client A
Client Y
Client Z
...
...
Netflix
Microservices
script
script
...
script
script
Network
boundary
API Server JVM
Strong
resiliency
with Hystrix
What about
resiliency on
this side?
groovy

22. Periodic
cleanup
New upload
increases
memory usage.

24. Js
(mostly)
java
Client A
Client B
Client C
Client A
Client Y
Client Z
...
...
Netflix
Microservices
script
script
...
script
script
Network
boundary
API Server JVM
few, small
scripts
fewer uploads
groovy

25. Js
(mostly)
java
Client A
Client B
Client C
Client A
Client Y
Client Z
...
...
Netflix
Microservices
script/app
script/app
script/app
script/app
...
script/app
script/app
script/app
script/app
Network
boundary
API Server JVM
script/app
script/app
~700 more
complex
scripts/apps,
10-50 uploads
per day
groovy

27. →
→

28. Lack of process isolation is a growing risk.

32. Js
(mostly)
java
Client A
Client B
Client C
Client A
Client Y
Client Z
...
...
Netflix
Microservices
node script
node script
...
node script
node script
Network
boundary API Server JVM
node.js
process
isolation

34. API
Temporarily
unavailable!

35. API

39. Docker Machine
local
project
Local Container
live reload file watcher
docker build / run
File watcher
agent
Proxy
Network
Agent
node-inspector
debugger

40. Js
(mostly)
java
Client A
Client B
Client C
Client A
Client Y
Client Z
...
...
Netflix
Microservices
script
script
script
script
...
script
script
script
script
Network
boundary
API Server JVM
script
script
Problems hard to
root cause, hard to
measure/optimize
performance
groovy

41. API
device
server-side
script
device client

42. API
device server-
side
script

47. ATLAS

48. Versioning
Easy
access to
instances
Rollback

50. Client A
Client B
Client C
Client E
Netflix
Microservices
node script
Network
boundary API Server JVM

51. Client A
Client B
Client C
Client E
Netflix
Microservices
node script
Network
boundary API Server JVM
Memory leak makes
RSL blow up.
Clearer idea of
where the problem
is.

52. node.js
Client A
Client B
Client C
Client E
Netflix
Microservices
node script
Network
boundary API Server JVM
Same with node script.

54. Js
(mostly)
Client A
Client B
Client C
Client A
Client Y
Client Z
...
...
Netflix
Microservices
node script
node script
...
node script
node script
Network
boundary API Server JVM
node.js

64. Watch the video with slide synchronization on
InfoQ.com!
https://www.infoq.com/presentations/netflix-
groovy-scripting