Redirect/Forward SOAP Web Service Requests to another Web Service
I have a use case that required all calls to NewWebService are routed to OldWebService, if the SOAP request does not validate against NewWebService's XSD and WSDL. NewWebService is located on ServerA and OldWebService is on ServerB.
Abstractly, I know I need some mechanism that will allow me to take a SOAP request that hits NewWebService, send it to OldWebService, then return the SOAP result back to the client. My limited experience with spring-ws is making it difficult to decide how to accomplish that.
My first thought was to build a SOAP client into the NewWebService that calls the OldWebService whenever the payload cannot be validated. Is this the best solution, or is there a better way to allow the NewWebService to act as a pass-through for certain requests?
Answer
My solution was to write a custom SoapRequestFilter that implements a javax.servlet.Filter and a new class that extends HttpServletRequestWrapper. Since HttpServletRequestWrapper implements the HttpServletRequest interface, extending the wrapper allows you to copy the HttpRequest and act on the stream without consuming the object and causing issues downstream.
Once I had the filter and wrapper, I was able to parse the endpoint and payload from the HttpRequest. If the request needed to be redirected, I created a new HttpUrlConnection to the old SOAP WebService and set the InputStream from that response to the OutputStream of the HttpResponse.