byManuel Correa

RestFul Web ServicesRestFul Web Services

REst = REpresentation State Tranfer

RestFul is a software architectural style

Stateless client-server architecture

Web Services are resources identify by an URL

e.g: www.mydomain.com/stock/GOOG

What are RestFul Web Services?What are RestFul Web Services?

What are RestFul Web Services?What are RestFul Web Services?

Application descriptionWSDL vs. WADL (Web Application Description Language)

Transport ProtocolSOAP vs. HTTP

Discovery and publishingUDDI vs. The Web (in general any url is a resource)

What are RestFul Web Services?What are RestFul Web Services?Comparison with SOAP Web ServicesComparison with SOAP Web Services

RestFul vs. SOAP debateRestFul vs. SOAP debate

REST SOAP

Use HTTP transport protocol SOAP over HTTP

Point to point communication Designed to distributed systems...

Simpler specification Heavy specification. To much XML flavors

Simple implementation Harder to develop

Any HTTP client will “work” Only SOAP clients

No require client API Must generate a SOAP client

RestFul vs. SOAP debateRestFul vs. SOAP debate

Companies are moving from SOAP web services to RestFul web services

RestFul web services are coming more popular because they are simpler to implement than SOAP

If you know HTTP you know Rest (My claim)...

Everything you can do with restful you can do it with SOAP...

Google Ajax API is now full restful with JSON output

Amazon offers SOAP and Restful interfaces. 80% developers are using REST

Yahoo Restful API to access Yahoo Web Services

ESRI with ArcGIS Server with Map Services (Also support SOAP)

Does anyone knows another company that is using Rest?

Who is using Restful?Who is using Restful?

HTTP: Hyper Text Transport Protocol

HTTP work with two functions: REQUEST and RESPONSE (client-server architecture)

Works over TCP/IP generally

A HTTP resource is identified by an URI

HTTP ReviewHTTP Review

Request header

GET /stocks/GOOG HTTP/1.1Accept application.xmlUser-Agent Mozilla...Accept-Language en-us...[BODY]

Request methods: HEAD, GET, POST, PUT, DELETE, TRACE, OPTIONS, CONNECT, PATCH

HTTP Review – RequestHTTP Review – Request

Response header

HTTP/1.1 200 OKServer: ApacheContent-type application/xmlContent-length 155Date Sun, 10 Oct 2010...[BODY]

Response codes 1xx: informational. 2Xx: Success. 3XX: redirection. 4XX Client error. 5XX: server error.

HTTP Review – ResponseHTTP Review – Response

Restful methods – Compare with SQLRestful methods – Compare with SQL

Action SQL HTTP(Rest)

Create Insert PUT

Read Select GET

Update Update POST

Delete Delete DELETE

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>

<application xmlns="http://research.sun.com/wadl/2006/10">

<doc xmlns:jersey="http://jersey.dev.java.net/" jersey:generatedBy="Jersey: 1.1.4 11/10/2009 05:36 PM"/>

<resources base="http://localhost:8084/RestFulServer/resources/">

<resource path="/stock">

<resource path="/{symbol}">

<param xmlns:xs="http://www.w3.org/2001/XMLSchema" name="symbol" style="template" type="xs:string"/>

<method id="getStock" name="GET">

<response>

<representation mediaType="application/xml"/>

<representation mediaType="application/json"/>

</response>

</method>

<method id="deleteStock" name="DELETE"/>

<method id="putStock" name="PUT"/>

<method id="postStock" name="POST">

<response>

<representation mediaType="application/xml"/>

<representation mediaType="application/json"/>

</response>

..

WADL SpecificationWADL Specification

Application/xml Application/json Applicaton/text Multipart/form-data

...

Restful Response Output typesRestful Response Output types

JSON JSON ( JavaScript Object Notation)( JavaScript Object Notation)

Lightweight inter-change format Language independent Easy for humans and machine to read

“stock”: {"lastestTrade":"2010-10-10T16:29:23.327-04:00","name":"Google Inc.","price":"415.5","symbol":"GOOG","volume":"200"

}

Stock.name = “GOOG”

http://www.json.org/

RESTFul Services◦ JAX-RS 1.0 (JSR 311)◦ Jersey framework

Client side◦ JavaScript (JQuery 1.2)◦ Java (HttpClient)◦ Curl◦ Any software/framework that supports HTTP and XML, JSON as response.

Others technologies (Server Side)◦ Spring Framework 2.5 (Context of the Web Application )◦ Hibernate/JPA (ORM to map the database – Model of the Application)◦ Oracle 10g

RestFul Java APIRestFul Java API

JAX-RS: Java specification for RestFul Web Services (JSR 311)

JAX-RS provides a set of Java annotations that allows you to annotate your POJO and give the Restful behavior

Restful implementation in JavaRestful implementation in Java

Annotation Description

@Path URI description

@GET, @POST, @PUT, @DELETE

Method description. Use of java methods to denote how to acces them

@Produces, @Consumes Define what is produced when a method is invoked. Consumes define what is allow in the input

@PathParam Parameter in the URI. eg. /stock/{symbol}

@QueryParam Parameter /stock/GOOG?hidePrice=true

Jersey: Java Framework that implements JAX-RS

Servlet base framework

https://jersey.dev.java.net/

Restful implementation in JavaRestful implementation in Java

NetBeans 6.8 Apache tomcat 6 Jersey and JAX-RS Application demo: Stocks information

RestFul Web Services - DEMORestFul Web Services - DEMO

DEMO

RestFul Web ServicesRestFul Web Services

Questions ?

RestFul Web ServicesRestFul Web Services