In this recipe, we will use the Publish action to asynchronously invoke a service from the proxy service message flow, without having to wait for the calling service to finish its processing.
For this recipe, we have an external Processing Service, available as a soapUI mock service which takes quite some time to do its processing. The interface in the Processing Service WSDL is defined synchronous. We have a business service Processing which allows us to invoke the external service from a proxy service.
Instead of directly invoking the business service from the Publish proxy service, an additional proxy service Processing is added, which only exposes a one-way interface. By doing that, the Publish proxy service can use a Publish action to invoke the Processing proxy service without having to wait for external service to complete.