How to build a rest api

1. Goals
Understand REST
 What
 Why
Get comfortable with ASP.NET Web API
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2. Agenda
Quick Demo
REST and Why You Should Care
Building an API with ASP.NET Web API
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3. Demo
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4. What is REST
Stands For:
 REpresentational State Transfer
Architectural Style based on HTTP
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5. What is HTTP?
Well defined protocol (web browsers, web servers, etc.)
 Request and Response
 Stateless
Request Contents
 URL
 HTTP Verb
 Header
 Message Body
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6. What is REST
Architectural Style based on HTTP
Resources (Things)
Verbs (Actions)
 GET, POST, PUT, DELETE, etc.
Response gives a representation of the resource (XML, JSON,
image, etc.)
More Info: http://en.wikipedia.org/wiki/REST
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7. Resources
GET
http://en.gravatar.com/userimage/7361283/02c115a8f3967a.jpg
GET https://www.diigo.com/user/jfjcn1/webApi
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8. HTTP Verbs
GET
 Gets 0 or more of a resource (thing)
POST
 Creates a resource (hopefully)
PUT
 Updates a resource (hopefully)
DELETE
 Deletes a resource (hopefully)
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9. REST in Action
Actions:
 GET
 POST
 PUT
 DELETE
Resources:
 http://somedomain.com/users/1
 https://otherdomain.com/products
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10. REST Responses
Responses come back as an HTTP Status Code + message (maybe)
HTTP Status Codes
 1XX – Request Received and I’m processing it
 2XX – Request Received and processed it successfully!
 3XX – Client must do something else to complete the request
 4XX – Client made an error
 5XX – Server error
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11. Popular Status Codes
200 – Success
201 – Created
301 – Moved Permanently (AKA “redirect”)
404 – Not Found
401 – Unauthorized
500 – Internal Server Error (AKA “oh crap!”)
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12. On to the codez…
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13. Why REST?
Everyone/everything speaks HTTP
Web applications are moving to JavaScript + AJAX
Lightweight compared to SOAP
Caching of resources (server decides)
 http://en.gravatar.com/userimage/7361283/02c115a8f3967a.jpg
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14. REST is NOT a standard
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15. Thank You!
fernando@TalentRiot.com
http://kaizencto.com
@avfernando
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