Difference between WSDL and WADL
WADL is the REST equivalent of SOAP's Web Services Description Language (WSDL), which can also be used to describe REST web services.
| Point of Distinction | WSDL | WADL |
|---|---|---|
| Acronym For | Web Services Description Language | Web Application Description Language |
| Definition | WSDL is an XML language for describing web services. Used to describe SOAP-based web services. | WADL is an XML file-format . It is an XML vocabulary for expressing the behavior of HTTP resources. It is an XML to describe RESTful web services. |
| How client load file | A client can load a WSDL file and get to know what methods web service can call, what are the arguments the methods expect and which data type it returns. | A client can load a WADL file and can access the complete functionality of the web service. |
| Easier to Read, Write & Understand | Not easy compare to WADL. WSDL is difficult to write and understand. | Easier than WSDL. WADL is lightweight. |
| XML to describes | XML to describe SOAP based Web Services | XML to describe RESTful Web services. WADL is a REST equivalent of SOAP's web service description language. |
| Relation with REST | WSDL 2.0 can be used to describe REST Web services and thus competes with WADL. But it has a wider scope. | WADL is REST equivalent of SOAP’s web service description language. |
| Binding to SMTP server | It has more binding to SMTP server | No binding to SMTP Server |
| Flexible | WSDL more flexible than WADL. | WADL covers all user expectation except Authentication, which is as simple as REST. |
| Design | Complex by Design | Simple By Design |
| Authentication | Authentication is involved for web services | No Authentication involved for web services |
| Standard | Only XML Parameter | Not a standard |
| URI template mechanism | The user needs to define xml input message to use the URI template mechanism | It requires a simple URI template mechanism. |
| Scope | More scope compared to WADL | Limited scope compared to WSDL |
| W3C Recommendation | W3C recommends WSDL interface | W3C does not recommend WADL interface |
| HTTP protocols | WSDL 1.1 only supports GET and POST methods whereas WSDL 2.0 supports HTTP protocol also. | WADL strictly support REST Service, only HTTP protocol. |
| Major Elements | <type>, <message>, <porttype>, <binding> | <grammers>, <resources>, <methods>, <representation> |
| What it defines | WSDL defines all major elements which may be defined 0 or more times except <types>. All definitions need not be in the same XML, one XML can import others. Hence comes the concept of Abstract and Concrete portions, where concrete imports abstract. | WADL defines both resources and representation, and methods to manipulate resources. |