Hypermedia APIs & Self-Building Apps

What if your application had all of the information it needed from your REST API to build itself? This session will use an example RESTful Hypermedia API running locally together with a live running custom-built mobile application to demonstrate how to automate building parts of a mobile application UI from a RESTful API response alone. We will then explore techniques to customize and fine-tune the UI while still automating most of the work from the API.

Transcript

1. Vance Lucas • Co-Founder, Brightbit http://brightb.it Hypermedia APIs & Self-Building Apps
2. Who are You? • Vance Lucas • http://vancelucas.com • @vlucas (for heckling) • Brightbit • http://brightb.it • Design, Development & Consulting for web apps, mobile apps and APIs
3. What is a REST API? Hypermedia API?
4. Developed by Leonard Richardson http://martinfowler.com/articles/richardsonMaturityModel.html
5. “Level 3” is a pre- condition of REST Roy T. Fielding http://roy.gbiv.com/untangled/2008/rest-apis-must-be-hypertext-driven
6. You must have hypermedia controls in your API to call it REST
7. “A REST API should be entered with no prior knowledge beyond the initial URI (bookmark) and set of standardized media types that are appropriate for the intended audience (i.e., expected to be understood by any client that might use the API). From that point on, all application state transitions must be driven by client selection of server-provided choices that are present in the received representations or implied by the user’s manipulation of those representations.” Roy T. Fielding http://roy.gbiv.com/untangled/2008/rest-apis-must-be-hypertext-driven
8. What are these “hypermedia controls”?
9. Two Key Things
10. Links
11. Forms
12. But you can’t make forms in an API! Whhaaaaa!
13. You Can. Kind of...
14. JSON Schema http://tools.ietf.org/html/draft-zyp-json-schema-03
15. JSON Schema { "description":"A person", "type":"object", "properties":{ "name":{"type":"string"}, "age" :{ "type":"integer", "maximum":125 } } }
16. URI Templates RFC 6570 http://tools.ietf.org/html/rfc6570
17. URI Templates http://uri.com/~{username}/ #-> http://uri.com/~fred/ http://uri.com/dictionary/{term:1}/{term} #-> http://uri.com/dictionary/c/cat http://uri.com/search{?q,lang} #-> http://uri.com/search?q=cat&lang=en
18. HAL Spec (Unofficial) http://stateless.co/hal_specification.html
19. HAL Specification { "_links": { "self": { "href": "/orders" }, "next": { "href": "/orders?page=2" }, "search": { "href": "/orders?id={order_id}" } }, "_embedded": { "order": [ { "_links": { "self": { "href": "/orders/123" }, "customer": { "href": "/u/bob", "title": "Bob" } }, "total": 30.00, "currency": "USD", "status": "shipped", "placed": "2011-01-16", } ] } }
20. Link “rel” Types http://www.iana.org/assignments/link-relations/link- relations.xml
21. No official spec for linking or describing resources for JSON or XML APIs
22. Too Boring; Didn’t Listen: Link and describe resources however you want, but be consistent.
23. DEMO TIME! App: https://github.com/vlucas/brightbudget-app API: https://github.com/vlucas/brightbudget-web
24. Questions? Rate this talk: https://joind.in/6205