Introducción

The REST architectural style

Representational state transfer (REST) is an abstraction of the architecture of the World Wide Web;

REST is an architectural style consisting of a coordinated set of architectural constraints applied to

within a distributed hypermedia system.

The term representational state transfer was introduced and defined in 2000 by Roy Fielding in his doctoral dissertation at UC Irvine.

The REST architectural style is often applied to the development of web services as an alternative to other distributed-computing specifications such as SOAP (Simple Object Access protocol).

Web Services

A Web Service is a method of communication between two electronic devices over a network.

It is a software function provided at a network address over the web with the service always on as in the concept of utility computing54.1.

The W3C defines a Web service generally as:

A software system designed to support interoperable machine-to-machine interaction over a network.

RESTful Web Services

One can characterize web services as RESTful if they conform to the constraints described in the architectural constraints.

Web service APIs that adhere to the architectural constraints are called RESTful.

HTTP based RESTful APIs are defined with these aspects:

  1. base URI, such as http://example.com/resources/
  2. an Internet media type for the data. This is often JSON54.2 but can be any other valid Internet media type (e.g. XML, Atom54.3, microformats54.4, etc.)
  3. standard HTTP methods (e.g., GET, PUT, POST, or DELETE)
  4. hypertext links to reference state
  5. hypertext links to reference related resources

The following table shows the HTTP methods that are typically used to implement a RESTful API.

RESTful API HTTP methods
Resource GET PUT POST DELETE
Collection URI, such as http://example.com/resources List the URIs and perhaps other details of the collection's members. Replace the entire collection with another collection. Create a new entry in the collection. The new entry's URI is assigned automatically and is usually returned by the operation. Delete the entire collection.
Element URI, such as http://example.com/resources/item17 Retrieve a representation of the addressed member of the collection, expressed in an appropriate Internet media type. Replace the addressed member of the collection, or if it doesn't exist, create it. Not generally used. Treat the addressed member as a collection in its own right and create a new entry in it. Delete the addressed member of the collection.

Safe and Idempotent Methods

Unlike SOAP-based web services, there is no "official" standard for RESTful web APIs. This is because REST is an architectural style, unlike SOAP, which is a protocol.



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Casiano Rodriguez León 2015-06-18