Use the Service Facade to WebSphere MQ: request-response pattern to provide a web service facade to functions that are accessible only through WebSphere MQ. This pattern creates a bridge between the synchronous HTTP protocol, which is typically used with web services, and existing applications with WebSphere MQ interfaces that cannot easily be upgraded.
Use this pattern where provider applications provide an XML interface and client applications support calls to web services. The pattern can be extended with transforms to support a service facade to applications with non-XML interfaces over WebSphere MQ.
The solution is to implement a message flow that provides a service entry point. When a service request is received, the reply identifier is stored on an internal queue and the request is forwarded to the provider application. When the response is received from the provider application, the reply identifier is recovered and a web services reply, which contains the provider response, is returned to the requesting application.
Read the following section for information about how to apply and use this pattern.
Constraints on the use of the pattern