REST overview

Web Services

(Legacy) System

Web Service API : 80

Web Services

(Legacy) System

Web Service API : 80

The Types of Web Services

Big Web Services

WS-Notification

WS-Security

WSDL

SOAP

REST

REST

RPC style

REST-RPC hybrid

RESTful Web Services

Representational State Transfer (REST) is a style of software architecture for

distributed hypermedia systems such as the World Wide Web. The term Representational

State Transfer was introduced and defined in 2000 by Roy Fielding in his

doctoral dissertation. Fielding is one of the principal authors of the Hypertext Transfer Protocol (HTTP) specification

versions 1.0 and 1.1.

Bookings

Routes

Passengers

HTTPApplication

Bookings

Routes

Passengers

Resources

HTTPApplication

/booking/{id}/

/route/{id}/

/passenger/{id}/

POSTGETPUT

DELETE

Application

Resources

/booking/{id}/

/route/{id}/

/passenger/{id}/

POSTGETPUT

DELETE

Application

ResourcesAddressable

/booking/{id}/

/route/{id}/

/passenger/{id}/

POSTGETPUT

DELETE

Application

ResourcesAddressableUniform

Interface

/booking/{id}/

/route/{id}/

/passenger/{id}/

Application

GET /booking/123/

Addressable Resources

/booking/{id}/

/route/{id}/

/passenger/{id}/

Application

GET /booking/123/

State and Representation

Addressable Resources

/booking/{id}/

/route/{id}/

/passenger/{id}/

Application

GET /booking/123/

State and Representation

Addressable Resources

id: 123, pickupTime: ‘2010-12-13T09:00:00’, passenger: { link: { href: ‘/passenger/234’, rel: ‘related’ } }

200 OK

REST = HTTP Used Right

REST was “developed” in parallel with the HTTP/1.1 protocol

Caching and conditional GET

Proxies

HTTP headers (e.g.content negotiation)

HTTP methods

Everything Is a Resource

There shall be nothing else

Everything Is a Resource

There shall be nothing else

ROA

Everything Is a Resource

There shall be nothing else

•Version 1.0.3 of the software release•The latest version of the software release•Search results for the word ‘Galactica’•The next prime number after 1024•The relationship between Alice and Bob•A list of open bugs in the bug database

Clean and Descriptive URIs

Clean and Descriptive URIs

/software/releases/1.0.3.tar.gz/software/releases/latest.tar.gz/search/Galactica/nextprime/1024/relationships/Alice;Bob/bugs/by-state/open

State(lessness)

Application vs. Resource

The Uniform Interface

The Uniform Interface

GET - safe, idempotentPUT - idempotentDELETE - idempotentPOST - “complex”

The Uniform Interface

200 - OK201 - Created301 - Moved Permanently400 - Bad Request404 - Not Found409 - Conflict500 - Internal Server Error

Connectedness

route

booking

passenger

Hypermedia as the Engine of Application State

route

booking

passenger

Problems?

Transactions

Asynchronous tasks

Batch jobs

Relationships between resources

Partial updates

Partial representations

REST WS*

Ignores HTTPGood tool supportWSDL“Standards”Plethora of Security Standards

Embraces HTTPNo bandwidth overheadSimplicityWeb already is RESTfulHTTPS / HTTP Diges, OAuth

Why?