Design REST-ful Web Service, Use Spring MVC as Example

1. Design REST-ful Web Service - Use Spring MVC as Example kevingo

2. REpresentationalState Transfer Apache co-founder Apache HTTP Server project developer HTTP 1.0 / 1.1 spec author Roy T. Fielding http://www.ics.uci.edu/~fielding/pubs/dissertation/rest_arch_style.htm

3. A style of software architecture for distributed hypermedia systems.

4. REST 是一種軟體架構風格適合用來開發Web Service

5. WHO USE REST

6. WHO USE REST

7. 向主流靠攏!

8. 萬物皆資源 Any information that can be named can be a resource { 'obj1': { 'child1':'value1', 'child2':'value2' }, 'array1': [1, 2, 3, 4, 5]} <People> <name>Fu</name> <Age>10</Age> </People>

9. 任何資源都用URL表達 http://itri.com/proj/i236 http://itri.com/people/kevingo

10. 相同資源，格式可能不同 http://xxx.com/article

11. 回想REST的全名… REpresentational 對於資源在特定時刻的狀態的描述 State 資源的狀態 Transfer 資源在ClientSide和Server Side之間的轉移

12. REST 說穿了 … Service Provider 我要 XXX 透過HTTP 這是 OOO

13. RESTful ?

14. RESTful … forget -> forgetful : 忘記 -> 健忘的 color -> colorful : 顏色 -> 多顏色的 peace -> peaceful : 和平 -> 和平的 ….

15. 同理可證

16. REST->RESTful 符合REST規範的

17. REST到底規範了什麼？

18. 使用URL來表達資源 工研院的i236計畫 http://itri.org/project/i236 參與工研院paas計畫的人員 http://itri.org/project/paas/people

19. 利用HTTP定義的動詞方法來進行資源的操作 GET POST PUT DELETE

20. Communicate Stateless

21. 其他還有… Cacheable Client–server Layered system Code on demand

22. RESTful URL design

23. http://itri.org/addProject?name=i236 http://itri.org/showProject?name=i236 http://itri.org/deleteProject?name=i236 http://itri.org/editProject?name=i236

24. GET http://itri.org/project/i236 DELETE POST PUT

25. REST的優點 Scalability - stateless 搜尋引擎喜歡Clean URL 統一的存取介面 –HTTPMethod 使用HTTP Catch和proxy server提高負載程度

26. 關於HTTP方法我們可以懂得更多

28. Spring MVC REST in Java Spring 3.0

29. annotation-based programming model

30. 使用annotation減少繼承宣告 配合context:component-scan 減少XML設定文件

31. @Controller 聲明這是一個Controller類別

32. @Controller public class ProjectController {…} 取代 public class ProjectController extends xxxController {…}

33. @RequestMapping 將請求轉交至對應的類別或方法

34. 可以用在類別上 @Controller @RequestMapping(value=“/projects”) public class ProjectController {…} 也可以用在方法上 @RequestMapping(value=“/projects”) public ModelAndView show() {…}

35. 還可以指定請求的方法 @RequestMapping(value=“/projects”, method=RequestMethod.POST) public ModelAndView show() {…} 連請求的header都可以指定 @RequestMapping(headers=“content-type=text/*”) public ModelAndView show() {…}

36. @PathVariable 將URL的參數和方法的參數 進行綁定

37. URL參數會傳入方法中 @RequestMapping(“/project/{name}”) public ModelAndView show(@PathVariable String name) {…}

38. 萬事俱備只欠東風

39. 瀏覽器只支援GET和POST

40. 貼心的Spring幫我們解決… 在web.xml加入HiddenHttpMethodFilter 1 使用spring form tag來指定http method (PUT or DELETE) 2 其實是用POST發出請求，只是偷偷塞了一個hidden field來放真正的HTTP Method 3 HiddenHttpMethodFilter會根據真正的HTTP Method幫我們轉發到正確的Controller

41. <form:form action="project" method="delete"> <input type="submit" value="Delete Project" name=“i236" /> </form:form> <form id="command" action="project/i236" method="post"> <input type="hidden" name="_method" value="delete"/> <input type="submit" value="Delete i236" name="i236" /> </form>

42. 偷偷看一下原始碼…

43. 還有什麼？

44. 每次要使用REST都要產生一個form？

45. 使用RestTemplate類別輕鬆呼叫RESTResources 謝謝Spring 3.0

46. GET – getForObject POST – postForObject PUT – put DELETE – delete ….. http://static.springsource.org/spring/docs/3.0.x/javadoc-api/org/springframework/web/client/RestTemplate.html

47. 還有一點點問題…

48. 怎麼做？

50. 使用額外參數/project/i236.json /project/i236.html /project/i236?format=json /project/i236?format=html

51. ContentNegotiatingViewResolver 支援瀏覽器Request Header 支援副檔名

53. application/xhtml+xml

54. application/xml

55. application/xml

56. application/xhtml+xml

57. text/html

58. text/plain

59. Image/png

60. iamge/jpeg

61. application/xaml+xml

62. application/x-ms-application

63. image/gif

64. Image/pjpeg

65. application/x-ms-xbap

67. 看一下DEMO吧…

68. 給你魚竿 - REST Roy Thomas Fielding 博士論文 http://www.ics.uci.edu/~fielding/pubs/dissertation/rest_arch_style.htm REST-ful URI design http://redrata.com/restful-uri-design/ REST 簡介 http://www.shlug.org/Slide/2011/2/REST.pdf RESTful Rails Development http://www.b-simple.de/download/restful_rails_en.pdf REST (Representational State Transfer) and RESTful web services: Methods, Concepts and Examples http://mauriziostorani.wordpress.com/2008/07/27/rest-representational-state-transfer-and-restful-web-services-concepts-and-examples/

69. 給你魚竿 - Spring MVC REST Spring API http://static.springsource.org/spring/docs/3.0.x/javadoc-api/ Spring MVC Rest http://www.slideshare.net/habuma/spring-mvc-rest REST in Spring 3: @MVC http://blog.springsource.com/2009/03/08/rest-in-spring-3-mvc/

70. curl -X DELETE http://itri.org/ReadingClub/kevingo/3 Thank you 