Chapter    21

Consuming RESTful Services

If you have a Twitter account or a Facebook account, when you use their mobile applications you are consuming their services via a REST API.

Representational State Transfer (REST) defines an architecture, not a protocol, for designing Web services that consume system resources. It defines how the resource states are accessed and transferred over HTTP.

The key features of REST Web services are:

  • They use HTTP methods only.
  • They are stateless.
  • Endpoints are defined as directory structures.
  • Data is transferred using XML, JSON or both.

HTTP Methods

There are four HTTP methods, GET, PUT, POST and DELETE. These methods are defined by the HTTP protocol.

  • GET is used to retrieve a resource from the server.

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