WADL is acronym for Web Application Description Language. WADL is championed by Sun Microsystems. WADL is lightweight, easier to understand, and easier to write than WSDL. In some respects, it is not as flexible as WSDL (no binding to SMTP servers), but it is sufficient for any REST service and much less verbose.
WADL is a machine readable XML description of HTTP based web-services.
WADL is intended to simplify the reuse of web services that are based on the existing HTTP architecture of the Web.
It is platform and language independent and aims to promote the reuse of applications beyond the basic use in a web browser.
WADL was submitted to the World Wide Web Consortium by Sun Microsystems on 31 August, 2009, however the consortium has no current plans to standardize it.
The service is described using a set of resource elements.
Each resource contains param elements to describe the inputs, and method elements which describe the request and response of a resource.
Step 1 − Double-click the REST service – “sample-service”. It will open the Service Overview wizard.
Step 2 − Click Service Endpoints.
The Service Endpoints tab defines any number of alternative endpoints for service, which can easily switch between the REST Request editor.
Step 3 − Click WADL- Content.
The tree to the left allows easy navigation between elements in all imported files. For example, selecting the GET method as in the screenshot above highlights it in the corresponding WADL file to the right.