Introduction to RESTful Web Services
•
2 likes•18,093 views
A textbook introduction to RESTful Web Services, the Web and the HTTP protocol. There has been a lot of hype about REST lately, but very few people understand how to implement RESTful Web Services correctly and how the Web actually works. Presented at ThoughtWorks.
Recommended
More Related Content
What's hot
What's hot (20)
Viewers also liked
Similar to Introduction to RESTful Web Services
Similar to Introduction to RESTful Web Services (20)
Recently uploaded
Recently uploaded (20)
Introduction to RESTful Web Services
- 1. a n i n t r o d u c t i o n t o RESTFUL WEB SERVICES Felipe Dornelas
- 2. AGENDA 2 ▫︎The Internet ▫︎The Web and its Resources ▫︎HTTP ▫︎The Resource-Oriented Architecture ▫︎RESTful Web Services
- 3. WHAT IS REST? 3 HTTP + Resource-Oriented Architecture
- 4. THE INTERNET A network of networks 4
- 5. 5
- 6. 6
- 10. CACHING 10
- 11. INTERNET LAYERS 11 Web, E-mail, BitTorrent, DNS… TCP, UDP… Internet Protocol (IP) WiFi, Ethernet, 3G, LTE…
- 12. INTERNET LAYERS 12 We will talk about the Web
- 13. THE WEB An application of the Internet 13
- 14. WHAT IS THE WEB? 14 An information system of interlinked hypertext documents and resources accessed via the Internet
- 16. HYPERTEXT MARKUP LANGUAGE 16 <!doctype html> <html> <head> <title>Example Hypertext Document</title> </head> <body> <div> <h1>Example Hypertext Document</h1> <p>This is an example hypertext document to be used for illustrative purposes.</p> <p><a href=“http://example.org”> Example Hyperlink</a></p> </div> </body> </html>
- 18. HYPERTEXT TRANSFER PROTOCOL 18 ServerClient HTTP Request example.comMozilla Firefox
- 19. HTTP REQUEST 19 GET / HTTP/1.1 User-Agent: Mozilla Firefox Host: example.com Accept: */*
- 20. HYPERTEXT TRANSFER PROTOCOL 20 ServerClient HTTP Response example.comMozilla Firefox
- 21. HTTP RESPONSE 21 HTTP/1.1 200 OK Content-Type: text/html Content-Length: 1270 <!doctype html> <html> <head> <title>Example Domain</title> </head> <body> … </body> </html>
- 22. 22
- 23. INTERNET LAYERS 23 HTTP TCP Internet Protocol (IP) WiFi, Ethernet, 3G, LTE…
- 24. RESOURCES 24 Anything that can be identified, named, addressed or handled on the Web
- 25. RESOURCES 25 ▫︎Can be concrete things: ▫︎Web pages ▫︎Files ▫︎Videos ▫︎Blog posts ▫︎Articles
- 26. RESOURCES 26 ▫︎Can also represent abstract concepts: ▫︎Employees in a enterprise ▫︎Money transfers ▫︎Products in a online store ▫︎Calendar appointments ▫︎User accounts
- 27. RESOURCE NAMES 27 ▫︎URN - Uniform Resource Name ▫︎products/54321 ▫︎about-us ▫︎articles/web.html ▫︎posts/2015-04-13 ▫︎podcasts/rest.mp3
- 28. RESOURCE LOCATORS 28 ▫︎URL - Uniform Resource Locator ▫︎http://example.com/products/54321 ▫︎http://example.com/about-us ▫︎http://example.com/articles/web.html ▫︎http://example.com/posts/2015-04-13 ▫︎http://example.com/podcasts/rest.mp3
- 29. ANATOMY OF AN URL 29
- 31. RESOURCE IDENTIFIERS 31 A resource only exists on the Web if it has an identifier (URI)
- 32. RESOURCES 32 HTTP can manipulate not only hypertext documents but any type of resources
- 34. READING A TEXT RESOURCE 34 http://example.com/hello-world.txt
- 35. READING A TEXT RESOURCE 35 GET /hello-world.txt HTTP/1.1 Host: example.com HTTP Request
- 36. READING A TEXT RESOURCE 36 HTTP/1.1 200 OK Content-Type: text/plain Content-Length: 13 Hello, World! HTTP Response
- 37. CREATING A TEXT RESOURCE 37 POST / HTTP/1.1 Host: example.com Content-Type: text/plain Hello, Mars! HTTP Request
- 38. CREATING A TEXT RESOURCE 38 HTTP/1.1 201 Created Location: /hello-mars.txt HTTP Response
- 39. CREATING A TEXT RESOURCE 39 http://example.com/hello-mars.txt
- 40. RESOURCE DOES NOT EXIST 40 http://example.com/hello-pluto.txt
- 41. RESOURCE DOES NOT EXIST 41 GET /hello-pluto.txt HTTP/1.1 Host: example.com HTTP Request
- 42. RESOURCE DOES NOT EXIST 42 HTTP/1.1 404 Not Found HTTP Response
- 43. HTTP CONTENT TYPES 43 ▫︎Determine the type of the HTTP payload ▫︎text/html - HTML ▫︎text/plain - Plain Text ▫︎audio/mpeg3 - MP3 files ▫︎application/xml - XML ▫︎…
- 45. HTTP STATUS CODES 45 ▫︎Success (2xx) ▫︎200 OK ▫︎201 Created ▫︎204 No Content ▫︎…
- 46. HTTP STATUS CODES 46 ▫︎Client Error (4xx) ▫︎400 Bad Request ▫︎404 Not Found ▫︎409 Conflict ▫︎…
- 47. HTTP STATUS CODES 47 ▫︎Server Error (5xx) ▫︎500 Internal Server Error ▫︎503 Server Unavailable ▫︎…
- 50. REST 50 HTTP + Resource-Oriented Architecture
- 51. REST 51 HTTP + Resource-Oriented Architecture RESTful
- 55. JSON REPRESENTATION 55 { "name": "Alice", "role": "Developer", "gender": "female" }
- 60. LIST EMPLOYEE RESOURCES 60 GET /employees HTTP/1.1 Host: example.com Accept: application/xml HTTP Request
- 61. LIST EMPLOYEE RESOURCES 61 HTTP/1.1 200 OK Content-Type: application/xml <employees> <employee href="/employees/alice"/> <employee href="/employees/bob"/> <employee href="/employees/eve"/> </employee> HTTP Response
- 62. READ EMPLOYEE RESOURCE 62 GET /employees/alice HTTP/1.1 Host: example.com Accept: application/xml HTTP Request
- 63. READ EMPLOYEE RESOURCE 63 HTTP/1.1 200 OK Content-Type: application/xml <employee> <name>Alice</name> <role>Developer</role> <gender>female</gender> </employee> HTTP Response
- 64. CREATE EMPLOYEE RESOURCE 64 POST /employees HTTP/1.1 Host: example.com Content-Type: application/xml <employee> <name>John</name> <role>QA</role> <gender>male</gender> </employee> HTTP Request
- 65. CREATE EMPLOYEE RESOURCE 65 HTTP/1.1 201 Created Location: /employees/john HTTP Response
- 66. UPDATE EMPLOYEE RESOURCE 66 PUT /employees/alice HTTP/1.1 Host: example.com Content-Type: application/xml <employee> <name>Alice</name> <role>Manager</role> <gender>female</gender> </employee> HTTP Request
- 67. UPDATE EMPLOYEE RESOURCE 67 HTTP/1.1 200 OK HTTP Response
- 68. DELETE EMPLOYEE RESOURCE 68 DELETE /employees/alice HTTP/1.1 Host: example.com HTTP Request
- 69. DELETE EMPLOYEE RESOURCE 69 HTTP/1.1 204 No Content HTTP Response
- 70. RESOURCE-ORIENTED ARCHITECTURE 70 1. Addressability 2. Statelessness 3. Connectedness 4. Uniform Interface
- 71. ADDRESSABILITY 71 Every interesting piece of information the server can provide should be exposed as a resource, and given its own URI
- 73. STATELESSNESS 73 Every HTTP request should happen in complete isolation
- 75. STATELESSNESS 75
- 76. STATELESSNESS 76
- 78. STATELESSNESS 78 Application State vs. Resource State
- 79. CONNECTEDNESS 79 Documents should contain not just data, but links to other resources
- 80. CONNECTEDNESS 80
- 81. CONNECTEDNESS 81
- 82. CONNECTEDNESS 82
- 83. CONNECTEDNESS 83 { "employees": [ "/employees/alice", "/employees/bob", "/employees/eve", ... ] "next_page": "/employees?start=10", "create_employee": "/employees" }
- 84. HATEOAS 84 Hypermedia As The Engine of Application State
- 85. UNIFORM INTERFACE 85 ▫︎Create: POST /employees ▫︎Read: GET /employees/alice ▫︎Update: PUT /employees/alice ▫︎Delete: DELETE /employees/alice ▫︎List: GET /employees
- 86. UNIFORM INTERFACE 86 ▫︎Create: POST /resource ▫︎Read: GET /resource/{name} ▫︎Update: PUT /resource/{name} ▫︎Delete: DELETE /resource/{name} ▫︎List: GET /resource
- 87. SAFETY 87 GET and HEAD never change the resource state
- 88. INDEMPOTENCE 88 PUT and DELETE are indempotent
- 91. BIG WEB SERVICES 91 ▫︎Heavy ▫︎Don’t scale ▫︎Hard to understand ▫︎Tight coupling ▫︎SOAP, WSDL, etc…
- 95. RESOURCE-ORIENTED ARCHITECTURE 95 1. Addressability 2. Statelessness 3. Connectedness 4. Uniform Interface
- 100. DISCOVERABILITY 100
- 101. DISCOVERABILITY 101 { "employees": [ "/employees/alice", "/employees/bob", "/employees/eve", ... ] "next_page": "/employees?start=10", "create_employee": "/employees" }
- 103. REFERENCE 103 RESTful Web Services Leonard Richardson Sam Ruby