How would you decide what style of Web Service to use? SOAP WS or REST?

In general, a REST based Web service is preferred due to its simplicity, performance, scalability, and support for multiple data formats. SOAP is favoured where service requires comprehensive support for security and transactional reliability.

The answer really depends on the functional and non-functional requirements. Asking the questions listed below will help you choose.

·    Does the service expose data or business logic? (REST is a better choice for exposing data, SOAP WS might be a better choice for logic).

·   Do the consumers and the service providers require a formal contract? (SOAP has a formal contract via WSDL)

·   Do we need to support multiple data formats? (REST supports multiple data formats)

·   Do we need to make AJAX calls? (REST can use the XMLHttpRequest)

·   Is the call synchronous or asynchronous? (REST only supports synchronous)

·   Is the call stateful or stateless? (REST is suited for stateless CRUD operations)

·   What level of security is required? (SOAP WS has better support for security)

·   What level of transaction support is required? (SOAP WS has better support for transaction management)

·    Do we have limited band width? (SOAP is more verbose)

·   What’s best for the developers who will build clients for the service? (REST is easier to implement, test, and maintain)