The Great API Redesign (API Conference 2018)

Redesigning a public web service API is a major undertaking: 3 years, thousands of hours of work, new clients, new documentation, a series of releases… This is the story of the DNSimple API v2, a project that started with a single, innocuous GitHub pull request with the title "Proposal for versioned API" in December 2013, and which came to a successful general availability launch at the end of 2016. Simone will explain some of the decisions that the team took over the last 3 years that shaped the development of the API as well as challenges the team faced, and provide you with tips and techniques that may help you in your next major API project. Finally, the important question: what’s next?

Transcript

1. The Great API Redesign Simone Carle7, DNSimple
3. @weppos
5. "This PR is a first step towards API versioning and using a dedicated hostname for API."
6. "This PR is a first step towards API versioning and using a dedicated hostname for API." Dec 28, 2013
7. Dec 28, 2013 v0 API v0
8. API v0 • Same hostname as website • No versioning • No metrics • Shared Rails controllers
9. It worked ™
10. GET https://dnsimple.com/domains.json GET https://dnsimple.com/domains.json
11. Jan 14, 2014 Dec 28, 2013 v0 v1 API v1
12. API v1 • Introduce hostname api.dnsimple.com • Introduce path-based versioning • SFll uses the same Rails controllers • Simple transiFon through minimal changes
13. GET https://api.dnsimple.com/v1/domains
14. Why a separate hostname? • Easily flag requests as API requests • Improved error handling due to clear indicaFon of what is an API call • Adds the ability to extract API code from controllers • Provides easier scaling
15. Why path-based versioning? The approach I followed is simple. May be not the most restful, but it's the one very commonly adopted that will also allow us to switch to a mime-based approach (in case we want to follow that route in the future).
16. Why path-based versioning? • API version is embedded in the path and it prefixes the URL • Everything in the URL is easily visible in logs • Easiest implementaFon for both producFon and consumpFon • HiSng path-based versioned APIs with a browser is easy • New versions increase the major number • Path and verb changes can be introduced at major version
17. Jan 14, 2014 Dec 28, 2013 v0 v1 API v1
18. Jan 14, 2014 Dec 28, 2013 v0 v1 v2 API v2
19. Separate ApplicaIon • Use of a separate (sub)applicaFon • No longer Fghtly coupled to the Rails controllers hWp:/ /hanamirb.org hWp:/ /confreaks.tv/videos/railsconf2016-developing-and-maintaining-a-pla\orm-with-rails-and-lotus
20. the Roadmap • MulF-account • Reusable shared business logic • Response serializaFon • PaginaFon, SorFng and Filtering • AuthenFcaFon • Rate limiFng • Webhooks • API clients
23. May 2, 2016 API clients Java PHP May 2, 2016 Sep 6, 2016 Sep 13, 2016 hWps:/ /slidr.io/weppos/using-go-to-guide-api-design-decisions-dotgo-2016
24. API clients • Developing clients gets easier with each new client • Common design paWerns emerge • Shared HTTP fixtures • We built a foundaFon for API clients development hWps:/ /blog.dnsimple.com/2017/01/api-client-tesFng-with-hWp-fixtures/
25. PrioriIes • Gathered metrics on v1 endpoint usage • PrioriFzed implementaFon based on usage
26. Jan 14, 2014 Mar 9, 2016 (Beta) Dec 13, 2016 (GA) Dec 28, 2013 v0 v1 v2 API v2
27. Stats • 717 Days from "Start" to "Finish" • 3 (almost) full-Fme team members out of 11 total, with a collaboraFve effort from the enFre DNSimple team • 4 official API clients, with 2 more under development • 75 API methods currently available (*) • 251 Ickets across 7 major milestones • ~423 API related support Ickets handled in the last year • ~1934 commits across the 4 API clients and applicaFon
28. What's next? • Adopt a formal language to describe the API • Deprecate and shut down API v1 • Facilitate transiFon to API v2 • Implement new methods (e.g. cerFficate, pricing)
29. Open API hWps:/ /www.openapis.org/
30. hWps:/ /blog.dnsimple.com/2018/02/openapi/
31. hWps:/ /blog.dnsimple.com/2018/04/openapi-in-depth/
33. TransiIon to v2 Measure Facilitate Deprecate
34. TransiIon to v2 Measure Facilitate Deprecate
35. TransiIon to v2 Measure Facilitate Deprecate
36. TransiIon to v2 Measure Facilitate Deprecate
37. TransiIon to v2 Measure Facilitate Deprecate
38. TransiIon to v2 Measure Facilitate
39. Lessons • Simple transiFon through minimal changes • Be a producer and a consumer • Provide official clients (and/or contribute) • Measure decisions • Invest into the API
40. Thanks! Simone Carle7 / / DNSimple hWps:/ /slidr.io/weppos @weppos