Hypermedia For Y'All

The presentation I gave at the RubyConf Brazil 2011.

Transcript

1. Roar! Nick „The German“ Sutterer @apotonick Hypermedia for y'all! The Missing Ingredient in REST
2. 2 Roar! 43.8 minutes... REST Representations Hypermedia Roooaaar
3. 3 Roar! REST?
4. 4 Roar! „architectural style for distributed hypermedia systems“ Roy Fielding's dissertation, chapter 5, line 1
5. 5 Roar! require 'rest' class Application include Restful end
6. 6 Roar! GET http://nick/state {„status“ : „sober“}
7. Roar! Resource Unique URL http://beer/rocky Uniform Interface GET POST PUT ... Represen- tation
8. Roar! „REST“ monolithic app pretty URLs GET renders models (JSON/HTML) POST to create and update models
9. Roar! Mono- lithic Systems
10. Roar! componentized app ...still pretty URLs real REST services with GET, PUT, POST, DELETE no HTML! embedded hypermedia REST
11. Roar! Split it!
12. Roar! BURP! Order!
13. Roar! BURP! Beer shop system Using RESTful backend services and a separate Presentation layer !
14. Roar! A typical REST session!
15. Roar! GET/PUT/ http://... ------------------- <document> ------------------- <document>
16. Roar! GET http://beers/1 name: Rocky alc : 6.0
17. Roar! POST http://beers/ ------------------- name: Beck's alc : 5.1 Created! It's at http://beers/becks
18. 18 Roar! GET: show POST: create PUT: update ... REST is
19. 19 Roar! CRUD is not REST!
20. Roar! A hypermedia- driven REST session!
21. Roar! BURP! Order!
22. Roar! BURP! REST Service Client
23. 23 Roar! BURP!
24. 24 Roar! BURP!
25. Roar! GET http://orders/1 id: 1 created_at: August 30 to proceed: http://orders/1/pay to update: http://orders/1
26. Roar! to proceed: http://orders/1/pay to update: http://orders/1 „ HATEOAS“ WTF?
27. Roar! „HATEOAS“ - embedd actions that make sense in current application state
28. Roar! {order: { id : 1 created_at: August 31 links : [ {rel : proceed href: http://orders/1/pay} {rel : self href: http://orders/1} ] } Hypermedia & JSON
29. Roar! rel : proceed href: http://orders/1/pay
30. 30 Roar! <link rel =„proceed“ href =„http://orders/1/pay“ />
31. Roar! rel – link semantic, „meaning“ href – resource URL
32. Roar! Creating a new order
33. Roar! POST http://orders ------------------------ client_id: 42 id : 1 client_id: 42 beers : [] links : [ {rel : self href: http://orders/1} {rel : beers href: http://orders/1/be ]
34. Roar! Single entry point – the one and only URL we know POST http://orders ------------------------ client_id: 42
35. Roar! id : 1 client_id: 42 beers : [] links : [ {rel: self href: http://orders/1} {rel: beers href: http://orders/1/beers} ] self link – pointing to current resource
36. Roar! id : 1 client_id: 42 beers : [] links : [ {rel: self href: http://orders/1} {rel: beers href: http://orders/1/beers} ] beers link – items placed in order
37. Roar! GET the new order
38. Roar! GET http://orders/1 id : 1 client_id: 42 beers : [] links : [ {rel : self href: http://orders/1} {rel : beers href: http://orders/1/be ]
39. Roar! Follow the beers link
40. Roar! GET http://orders/1/beers beers: [] links: [ {rel : self href: http://orders/1/be {rel : order href: http://orders/1}
41. Roar! Add beer to order
42. Roar! POST http://orders/1/beers ------------------------ {name: Anchor Steam} Created! It's at http://orders/1/beers/anchors team Created! It's at http://orders/1/beers/anchors team
43. Roar! Reloading the order
44. Roar! GET http://orders/1 id : 1 client_id: 42 beers: [ {name: Anchor Steam links: [ {rel : self href: http://orders/1/ ]} ],
45. Roar! id : 1 client_id: 42 beers: [ {name: Anchor Steam links: [ {rel : self href: http://orders/1/beers/anchorsteam} ]} ], links: [ {rel: self href: http://orders/1} {rel: beers href: http://orders/1/beers} ] +
46. Roar! id : 1 client_id: 42 beers: [ {name: Anchor Steam links: [ {rel : self href: http://orders/1/beers/anchorsteam} ]} ], links: [ {rel: self href: http://orders/1} {rel: beers href: http://orders/1/beers} ] +
47. Roar! +
48. Roar! Removing beer from order
49. Roar! DELETE http://orders/1/beers/anchorsteam +
50. Roar! Reloading the order
51. Roar! GET http://orders/1 id : 1 client_id: 42 beers : [] links : [ {rel : self href: http://orders/1} {rel : beers href: http://orders/1/be ]
52. Roar! GET http://orders/1 id : 1 client_id: 42 beers : [] links : [ {rel : self href: http://orders/1} {rel : beers href: http://orders/1/be ]
53. 53 Roar! http://orders/ POST GET GET + DELETE ? GET POST
54. 54 Roar! What we didn't do... PUT http://orders/1 DELETE http://orders/1/items ...
55. 55 Roar! Code!
56. Roar! Roar!
57. gem 'roar'
58. 58 Roar! class Beer include Roar::Representer::JSON property :name property :id link :self do beer_url(id) end Plain properties Hypermedia support yo
59. 59 Roar! Beer.new(:id => 1, :name => "NickBrew").to_json from Roar {"beer":{ "id" : 1, "name" : "NickBrew", "links": [{"rel":"self","href":"http://beers/1"}]}}
60. 60 Roar! brew = Beer.from_json '{"beer":{ "id" : 1, "name" : "NickBrew"}}' from Roar brew.name #=> „NickBrew“
61. 61 Roar! class Beer include Roar::Representer::XML ... jaja brew.to_xml <beer> <id>1</id> <name>NickBrew</name> <link rel="self" href="http://beers/1"/> </beer>
62. 62 Roar! class Order include Roar::Representer::JSON collection Beer
63. 63 Roar! class Collection include Roar::Representer::JSON link :next do page_url(page) end end class Beers < Collection collection Beer
64. 64 Roar! brew.new(:name => „SKOL“) brew.new(:name => „SKOL“) brew.extend Feature::HTTPVerbs brew.new(:name => „SKOL“) brew.extend Feature::HTTPVerbs brew.post!(„http://beers“) brew.new(:name => „SKOL“) brew.extend Feature::HTTPVerbs brew.post!(„http://beers“) puts „I'm at“ + brew.links[:self] #=> „http://beers/99“
65. 65 Roar!
66. 66 Roar! „REST APIs must be hypertext-driven“: http://roy.gbiv.com/untangled/2008/rest-apis-must-be- hypertext-driven REST in Practice – O'REILLY RESTful Web Services Cookbook – O'REILLY
67. 67 Roar! Are you local?
68. Roar! Thirsty? http://github.com/apotonick/roar @apotonick