This is a session given by Zane Claes at Nordic APIs 2016 Platform Summit on October 25th, in Stockholm Sweden. Description: Too often, APIs are only consumed by mobile apps and external services. This leads to inconsistencies between web and API implementations of core business logic. This talk will discuss how Airbnb created an API infrastructure that also powers our website, to create a single source of truth.

1. Airbnb’s API:
The Source-of-Truth
COMMUNICATIONS INFRASTRUCTURE / ZANE CLAES

2. Airbnb Mobile Evolution
(2011 - 2015)

7. Ghosts of Airbnb Past
Or: How we Became API-Centric

8. The Dangers of Hockey Sticks

9. API v1
(Ruby / Monorail)

10. API v1 Web Controller

11. • Duplicated Work: Web. Mobile Apps. MoWeb. Lantern. Etc.
• Inconsistent Behavior: Entirely different code paths.
Payments on mobile, different than payments on web.
• Difficult to Scale: Direct data access prevents moving to
Service-oriented Architecture. Monorail contains too many
tables.
• Poor Security: Access enabled by default. Leaks PII. Difficult
to have good security policy.
• No Type Safety: Crashes app, due to unpredictable types in
returned fields.
• More Website Downtime: Due to cascading updates, and
service entanglement.
Problems

12. API v1 Web Controller

13. Graphist
(A Ruby Gem/Framework for Building APIs)

14. • Code Reusability: Write once. Share with web, mobile, etc.
• Consistency: Everything works the same across platforms.
• Security: Security is at the forefront: do not leak sensitive data.
• Performance: Process more stuff, faster.
API v2 is continuously improved and optimized.
• Scalability: Easier to move to Service-oriented Architecture.
Free to change and improve underlying functionality.
• Better Debugging: Now you can actually debug.
Benefits
of API v2 (“Graphist”)

15. • Hundreds of Developers
• Thousands of Endpoints
• Dozens of Services
Where it’s Used

16. Graphist: Our Ruby Gem for APIs
(2016 and Beyond)

17. Android
Javascr
ipt
iOS
Graphist
Ruby
HTTP
Inline
Service
s
Graphist is a DAO (“Data Access Object”)

18. REST
or
GraphQL
REST and GraphQL are Interchangeable
Client
Graphis
t
No need to change a single line of code.

19. Client-Centric
Shifts the impetus of
“formats” to the client;
no more dev back-
and-forth.
Efficient
Solves over-fetching,
under-fetching, even
versioning; cross-
platform tools.
Community
Ready-made
developer tools:
sandbox,
documentation
explorer.
Flexible
Allows for arbitrary
functions, renamed
attributes, and more.
Why GraphQL?

20. Client
User Service
Client
Listing
Service
Review
Service
Client
Microservice Distributed DAOs

21. Questions?
Want to Talk APIs?
zane.claes@airbnb.com