APIs are Interfaces Too

APIs are not just hooks for one machine to connect to another — they’re interfaces, just like the user interface of your website or app. Your users are the developers who write code against your service, and a lot of the same interface design principles that we use for UI design hold for APIs as well.

In this talk, I take a deep dive into one corner of the Facebook API to illuminate how API consistency is critically important during the design process.

Transcript

1. APIS
2. the
 holy steer of Memphis Apis Memphis X Not
3. Application Programming Interfaces
4. Me • Ruby/iOS/JS since 2008 • Senior Developer at eSpark • Previously: Wunderlist, 
 Facebook marketing, 
 healthcare IT
7. APIs are important
8. API design makes a difference ?
9. Case Study
12. Yippie
16. ???
19. Yippie
25. ??? ??? ??? ??? ??? ??? ??? ???
28. WAT
29. Why?
30. Thing is... • The FB API is actually quite well designed • Strong fundamental pattern • Not amateurs
31. What went wrong?
32. APIs are Interfaces
33. Principle of Least Surprise http://en.wikipedia.org/wiki/Principle_of_least_astonishment "People are part of the system. The design should match the user's experience, expectations, and mental models." What is least surprising may however depend on the expected audience, e.g. end users, programmers or system administrators.
34. Developers are our users
39. Avoid Inconsistency
40. Consistency is key • Consistent format • Consistent naming • Consistent function
41. Perspective • Put yourself in another developer's shoes • Even for an internal API • Extra effort, but it pays off over time
42. Consideration • Make decisions about your API early on • Or right now! • Define how it should behave
43. Building an SDK • Consuming your own API is the best test • Can you build simple, consistent methods?
44. def set_app_restrictions(new_settings) graph_call(app_id, { restrictions: new_settings.to_json }) end
45. def set_app_restrictions(new_settings) if new_settings[“age_distribution”] new_settings[“age_distribution”] = new_settings[“age_restrictions”].to_json end graph_call(app_id, { restrictions: new_settings.to_json }) end
46. Thanks! Questions? @arsduo