REST-baserade tjänster med WCF ASP.NET Web APIRobert Folkesson

Active Solution

WHO AM I?

REST?• Dissertation by Roy Fielding 2000• “Architectural Styles and the Design

of Network-based Software Architectures”

• ReST = Representational State Transfer

Architectural constraints• Client–server• Stateless• Cacheable• Layered system• Uniform Interface

Scalability

GET http://fabrikam.com/API/User/42

Guiding principles of REST-interfaces

• Identification of resources• Manipulation of resources through

representations of these resources• Self-descriptive messages• Hypermedia as the engine of

application state

HATEOASHypermedia as the engine of application state

Example of hypermedia representation (Netflix)

Richardsons maturity model

Level 0: The swamp of POX

Level 1: Resources

Level 2: HTPP Verbs

Level 3: Hypermedia Controls

Glory of REST

REST on Microsoft – some history

• WCF pre-3.5: painful…• WCF 3.5: WebHttpBinding. • WCF REST Starter Kit (no longer

supported)• WCF Data Services (OData)• WCF Web API - Preview 1 - 6

WCF ASP.NET Web API

http://www.asp.net/web-api• Goal: One HTTP/ REST / Hypermedia API Fx• Integrated in ASP.NET: Best of both world

WCF to ASP.NET Web APIWCF Web APIASP.NET Web API

Service => Web API controllerOperation => ActionService contract => n/aEndpoint => n/aURI templates => ASP.NET RoutingMessage handlers => SameFormatters => SameOperation handlers => Filters, model binders

DEMO – FILE NEW

Media types & Media Formatters

HTTP/1.1 200 OK

Content-Length: 95267

Content-Type: image/png

Accept: text/html,application/xhtml+xml,application/xml

Media types & Media Formatters

• Built in support for: – XML– JSON– form-urlencoded data

• Can be extended with custom Media Formatters

DEMO – MEDIA TYPE FORMATTER

Web API on NuGet• Web API hosted in ASP.NET:

– AspNetWebApi

• Self-hosted Web API: – AspNetWebApi.Selfhost

• HttpClient including XML and JSON formatters: – System.Net.Http.Formatting

• JsonValue for navigating and manipulating JSON:– System.Json Newtonsoft.Json

Node-style Web API?

LiteWebServer server = new LiteWebServer("http://localhost"); server.Get("/Hello", (r) => new HttpResponseMessage() { Content = new StringContent("Hello World!") }); server.Post("/Echo", (r) => new HttpResponseMessage() { Content = new StringContent( r.Content.ReadAsStringAsync().Result) }); server.Open();

http://blogs.msdn.com/b/youssefm/archive/2012/02/24/writing-a-lightweight-web-service-using-webapi-building-blocks.aspx

DEMO – SELF HOSTING

Web API can be used for all levels

Level 0: The swamp of POX

Level 1: Resources

Level 2: HTPP Verbs

Level 3: Hypermedia Controls

Glory of REST

ASP.

NET

Web

API

OAuth/Claims based security

http://zamd.net/

Open Source: http://aspnetwebapi.codeplex.com

Some good reading

Thank you!

Robert Folkesson | Active Solutionrobert.folkesson@activesolution.se | @rfolkes

www.robertfolkesson.se