Spring RESTBucks - A Hypermedia REST Web Service

Transcript

1. © 2013 SpringOne 2GX. All rights reserved. Do not distribute without permission. A hypermedia-driven REST web service Oliver Gierke Spring RESTBucks
2. Oliver Gierke Spring Data engineer Core / JPA / Mongo JPA Expert Group ogierke@vmware.com www.olivergierke.de olivergierke
3. Spring Data Modern Data Access For Enterprise Java NoSQL JPA JDBC Redis Big Data Hadoop HBase MongoDB Neo4j REST exporter Roo Hive Pig Querydsl Repositories Gemfire Splunk Free e-book for every attendee!
4. Agenda I RESTBucks Spring Data Introduction Advanced Spring Data
5. Agenda II Spring Data REST Spring MVC integration testing Advanced Spring Data REST
6. RESTBucks An introduction
8. RESTBucks
9. RESTBucks Starbucks (like) coffee ordering Order / Payment
11. payment expected 1
12. payment expected 1 2
13. payment expected cancelled 1 2 3
14. payment expected preparing cancelled 1 2 3 4
15. payment expected preparing cancelled ready 1 2 3 4 5
16. payment expected preparing cancelled ready completed 1 2 3 4 5 6
17. Spring RESTBucks
18. Spring RESTBucks Sample implementation Using Spring technologies http://bit.ly/spring-restbucks
19. Technologies Spring Framework (4.0 M3) Spring Data JPA (1.4.1 / Babbage) Spring Data REST (2.0 snapshots) Spring HATEOAS (0.8)
20. Web Service Repository - Orders Spring Data Spring Data REST Payment Spring Data Manual implementation Manual implementation
21. Demo
22. Web Service Repository - Orders Spring Data Spring Data REST Payment Spring Data Manual implementation Manual implementation
23. Spring Data Convenient data access layers
24. Spring Data General introduction Repositories abstraction
25. Lab
26. Lab Setup Spring through JavaConfig Setup JPA in Spring context Enable Spring Data JPA Write integration tests for data access
27. Spring Data REST Easily export repositories to the web
28. REST Basics
29. REST in a nutshell Resources Identifier Uniform interface Representations Hypermedia
30. "HATEOAS - the word, there's no pronounciation for. (Ben Hale, SpringOne2GX 2012)
31. Hypermedia Clients driven by links and their relation types
32. Implementation Patterns Resource per aggregate root GET, PUT, POST, DELETE Relations as links Media type design
33. Spring Data REST
34. Spring Data REST Export Spring Data repositories to the web Allow configuration and extension
35. Lab
36. Lab Setup Servlet 3.0 web app with Spring Activate Spring Data REST Spring MVC integration test setup Write web integration tests
37. Hypermedia Diving into hypermedia details
38. payment expected preparing cancelled ready completed 1 2 3 4 5 6
39. Method URI Action Step POST /orders Create new order 1 POST/PATCH /orders/4711 Update the order (only if "payment expected") 2 DELETE /orders/4711 Cancel order (only if "payment expected") 3 PUT /orders/4711/payment Pay order 4 Barista preparing the order Barista preparing the order Barista preparing the order Barista preparing the order GET /orders/4711 Poll order state 5 GET /orders/4711/receipt Access receipt DELETE /orders/4711/receipt Conclude the order process 6
40. Challenges
41. Challenges How to avoid hard coding URIs?
42. Use link relations
43. orders Returns all orders available in the system order Returns a single order self The uri value can be used to GET the latest resource representation of the order. cancel This is the URI to be used to DELETE the order resource should the consumer wish to cancel the order. update Consumers can change the order using a POST to transfer a representation to the linked resource. payment The linked resource allows the consumer to begin paying for an order. Initiating payment involves PUTting an appropriate resource representation to the specified URI. receipt The URI to access the receipt using GET and conclude the order by taking the receipt (use DELETE).
44. orders Returns all orders available in the system order Returns a single order self The uri value can be used to GET the latest resource representation of the order. cancel This is the URI to be used to DELETE the order resource should the consumer wish to cancel the order. update Consumers can change the order using a POST to transfer a representation to the linked resource. payment The linked resource allows the consumer to begin paying for an order. Initiating payment involves PUTting an appropriate resource representation to the specified URI. receipt The URI to access the receipt using GET and conclude the order by taking the receipt (use DELETE).
45. Method URI Action Step POST /orders Create new order 1 POST/PATCH /orders/4711 Update the order (only if "payment expected") 2 DELETE /orders/4711 Cancel order (only if "payment expected") 3 PUT /orders/4711/payment Pay order 4 Barista preparing the order Barista preparing the order Barista preparing the order Barista preparing the order GET /orders/4711 Poll order state 5 GET /orders/4711/receipt Access receipt DELETE /orders/4711/receipt Conclude the order process 6
46. Method Relation type Action Step POST orders Create new order 1 POST/PATCH update Update the order (only if "payment expected") 2 DELETE cancel Cancel order (only if "payment expected") 3 PUT payment Pay order 4 Barista preparing the order Barista preparing the order Barista preparing the order Barista preparing the order GET order Poll order state 5 GET receipt Access receipt DELETE receipt Conclude the order process 6
47. Challenges How to implement: "only if payment expected"?
48. Process modeling
49. Root resource The only URI known GET /
50. { links : [ { rel : "orders", href : "…/orders" } ] }
51. Place order Access root resource Follow orders link $.links[?(@.rel="orders")].href POST /orders
52. { links : [ { rel : "orders", href : "…/orders" } ] }
53. { links : [ { rel : "self", href : … }, { rel : "cancel", href : … }, { rel : "update", href : … }, { rel : "payment", href : "…/orders/4711/payment" } ], content : { items : [ { drink : "Cappucino", size : "large", milk : "semi" price : 4.2 } ], location : "take-away", price : 4.2 status : "payment expected" } }
54. Trigger payment Follow payment link $.links[?(@.rel="payment")].href PUT /orders/4711/payment
55. { links : [ { rel : "self", href : "…/orders/4711" }, … { rel : "payment", href : "…/orders/4711/payment" } ], content : { items : [ { drink : "Cappucino", size : "large", milk : "semi" price : 4.2 } ], location : "take-away", price : 4.2 status : "payment expected" } }
56. { links : [ { rel : "self", href : "…/orders/4711/payment" }, { rel : "order", href : "…/orders/4711" } ], content : { creditCard : [ { number : "1234123412341234", cardHolder : "Oliver Gierke", expiryDate : "2013-11-01" } ], amount : { currency : "EUR", value : 4.2 } } }
57. Poll order Follow order link $.links[?(@.rel="order")].href GET /orders/4711 ETag / If-None-Match
58. { links : [ { rel : "self", href : "…/orders/4711/payment" }, { rel : "order", href : "…/orders/4711" } ], content : { creditCard : [ { number : "1234123412341234", cardHolder : "Oliver Gierke", expiryDate : "2013-11-01" } ], amount : { currency : "EUR", value : 4.2 } } }
59. { links : [ { rel : "self", href : "…/orders/4711" } ], content : { items : [ { drink : "Cappucino", size : "large", milk : "semi" price : 4.2 } ], location : "take-away", price : 4.2 status : "preparing" } }
60. Poll order Use caching ETag / If-None-Match until…
61. { links : [ { rel : "self", href : "…/orders/4711" }, { rel : "receipt", href : "…/orders/4711/receipt" } ], content : { items : [ { drink : "Cappucino", size : "large", milk : "semi" price : 4.2 } ], location : "take-away", price : 4.2 status : "ready" } }
62. Access receipt Follow receipt link $.links[?(@.rel="receipt")].href GET /orders/4711/receipt
63. { links : [ { rel : "self", href : "…/orders/4711" }, { rel : "receipt", href : "…/orders/4711/receipt" } ], content : { items : [ { drink : "Cappucino", size : "large", milk : "semi" price : 4.2 } ], location : "take-away", price : 4.2 status : "ready" } }
64. Conclude order Follow receipt link $.links[?(@.rel="receipt")].href DELETE /orders/4711/receipt
65. Background
66. Hypermedia VS. Java Frameworks
67. HTTP Methods URI Mapping Content negotiation Hypermedia Spring MVC JAX-RS ✓ ✓ ✓ ✓ ✓ ✓ ? ?
68. Spring HATEOAS
69. Spring HATEOAS Representation models LinkBuilder API Representation enrichment http://bit.ly/spring-hateoas
70. DEMO
71. DEMO
72. Miscellaneous Spring MVC integration testing REST Shell
73. Spring Data REST
74. Spring Data REST Exports JPA repositories as resources Hypermedia driven representations Extension points http://bit.ly/sd-rest
75. REST Shell
76. Thank you!
77. Resources
78. Further talks Spring Data Repositories - Best practices - Wed 10:30am Multi Client Development with Spring - Wed 4:30pm
79. Code Spring HATEOAS Sample Spring RESTBucks Spring Data REST Spring HATEOAS REST Shell
80. Books REST in Practice REST und HTTP RESTful WebServices Cookbook Spring Data
81. Videos Hypermedia APIs - Jon Moore Hypermedia APIs with Spring