RESTful, Resource-Oriented Architectures: a Model-Driven Approach

Sandy Pérez1, Frederico Durao2, Santiago Meliá3, Peter Dolog2, Oscar Díaz1

1st International Symposium on Web Intelligent Systems & ServicesDecember 12th, 2010

S. Pérez, F. Durao, S. Meliá, P. Dolog & O. Díaz

MODEL DRIVEN DEVELOPMENT

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Model Driven Development

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Data-intensive Web Applications

Data-intensive Web applications are built around the so-called “Domain Model”

This Domain Model is then complemented with other models that capture additional perspectives of the applications:

• Navigational Model• Presentation Model• Architectural Model

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Domain model

The Domain Model captures the main entities and relationships found in the application domain.

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Navigational Model

It specifies the data to be presented as a view of the Domain Model, and the order in which this data is to be presented

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Architectural Model

It is a component-based architectural style that represents a structural view of the application

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From Navigational Model to Architectural Model

client

server

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NEW ARQUITECTURAL STYLE: REST

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REST is becoming very popular

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Platform Evolution: REST

Order PSMREST

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GET /users HTTP/1.1

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RESTful, Resource-Oriented Architectures (ROAs) ROA is a specific set of guidelines of an implementation of the

REST-style architecture.

ROAs are based on four concepts:• Resources

• Their names (URIs). The URI is the name and address of a resource.

• Their representations. A resource is a source of representations.

• The links between them.

Client Serverfriends

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RESTful Web Services

RESTful Web services are simple Web services implemented using HTTP and the principles of REST.

They expose standard HTTP objects (i.e. resources) that respond to one or more of the six standard HTTP methods: GET, HEAD, POST, PUT, DELETE, and OPTIONS.

Client Server

GET /users HTTP/1.1users

Problem Statement

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Can RESTful services be generated?

Order PSMREST

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From a RPC façade to a RESTful facade

client

server

GETHEADPUTPOSTDELETEOPTIONS

How?

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The Architectural Model in Details

GETHEADPUTPOSTDELETEOPTIONS

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Resources + URIs + OperationType + Parameters

Contribution

Application Facade Component Model

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Obtaining RESTful interfaces from PIM

Order PSMREST

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…any NavigationalClass with at least one outgoing traversal link or service link at the Navigational Model.

Resource are obtained from …

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URIs are obtained from …

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+

Operation Types are obtained from …

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Representations: JSON By Default

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1. Path

2. Link stereotypes

Parameters are obtained from …

Conclusions

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Conclusions

Data-intensive Web Applications naturally match the REST architectural style

(Part of) the RESTful interface can be derived from the Domain & Navigation model

• Except:– the representation type: JSON by default– the operation type (delete, post): it should be annotated by

the designer