GxRest

About REST

Basically, REST is an architecture you can use when calling APIs or making APIs available to be called. It is independent of what's happening on either side, and what other software is being used when sending or receiving the REST calls. You can write an application that runs on a Mac, Windows, Linux, an Android phone or tablet, iPhone, iPod, or web site, and use the same REST API for all of those platforms. Data can be passed in and/or out when the REST API is called. The REST API doesn't care from what platform it's called – what's important is the information passed in the request and the data provided in the response.

Goals and Principles

The gCube eXtensions to the REST Protocol (gxRest) is set if Java libraries designed to provide convenient round-trip interaction between a Restful web application (also known as "service") and its clients.

Exploitation

gxRest has the flexibility for different degrees of exploitation of the library:

• it can be entirely adopted both at client and service side with full benefit of its conventions;
• it can be used just to send REST requests based only on plain HTTP;
• it can be used to parse the HTTP code of a response;
• it can be used only to return HTTP codes from the service.
• it can be used only to return Exceptions from the service.

Module: gxHTTP

gxHTTP defines the HTTP interface for a client of a gCube service and basic extensions to plain HTTP requests with zero-dependencies. More specifically, it help create context-aware requests sent from a client to a web application. No support for managing responses both at service and client side is provided.

Module: gxJRS

gxJRS is much more advanced than gxHTTP and offers fully-fledged extensions built on top of JAX-RS and gxHTTP.

Prominent features of gxJRS are:

• to achieve independence from the web framework used to develop the web application;
• to guarantee the correctness of requests/responses across the D4Science infrastructure;
• to abstract over the HTTP-based details required by the gCube framework when invoking a remote service;
• to avoid that each service implements its own conventions over the returned responses;
• to return error responses at the familiar (for any Java programmer) level of exceptions and error codes, while web frameworks usually just let return an HTTP status, headers and streams.

Integration with the client libraries of FWS

gxRest smoothly integrates with the client libraries (common-jaxrs-client, common-clients) of the FeatherWeight Stack by providing a request (GXWebTargetAdapterRequest) fully compatible with javax.ws.rs.client.WebTarget. The integration is described in a dedicate section of the request page.