🗊Презентация RestFul Services. Part 2

RestFul Services. Part 2.

Agenda What is Rest? Conceptual overview Restful Web services SOAP vs REST High-level example: hotel booking Technologies Using HTTP to build REST Applications

Conceptual Overview Representational State Transfer (REST) Representational State Transfer (REST) A style of software architecture for distributed hypermedia systems such as the World Wide Web. REST is basically client/server architectural style Requests and responses are built around the transfer of "representations" of "resources". REST is centered around two basic principles: Resources as URLs. A resource is something like a "business entity" in modelling lingo. It's an entity you wish to expose as part of an API. Almost always, the entity is a noun, e.g. a person, a car, or a football match. Each resource is represented as a unique URL. Operations as HTTP methods. REST leverages the existing HTTP methods, particularly GET, POST, PUT, and DELETE.

RESTful Web Service definition A RESTful Web service is: A set of Web resources. Interlinked. Data-centric, not functionality-centric. Machine-oriented. Like Web applications, but for machines. Like SOAP, but with more Web resources.

SOAP

A SOAP service has a single endpoint that handles all the operations – therefore it has to have an application-specific interface. A RESTful service has a number of resources (the collection, each entry), so the operations can be distributed onto the resources and mapped to a small uniform set of operations.

Hotel booking workflow Hotel booking workflow Retrieve service description Submit search criteria according to description Retrieve linked details of interesting hotels Submit payment details according to selected rate description Retrieve confirmation of booking 2b. Retrieve list of user's bookings

search(date, city) search(date, city)  list of hotels & rates getHotelDetails(hotel)  hotel details reserve(rate, creditCard)  confirmationID getConfirmationDetails(confID)  confirmation details listMyBookings()  list of confirmationIDs

RestFull Services. Technologies Todays’s set of technologies, protocols and languages used to apply RESTful paradigm: HTTP as the basis XML and JSON for data exchange AJAX for client-side programming (e.g. browser)