OSB call multiple Business Services and combine the responses into one

Question

Dear All,
I am new to OSB and I have a use case that I need to solve. I have 3 web services and I imported their WSDLs into OSB and created 3 Business Services that goes with each WSDL. The scenario is like this.
Business Service 1: takes an input value as [Region] and returns a list of employee names.
Business Service 2: takes the list of employee names and returns the list of employee names with their job profile
Business Service 3: takes the list of employee names with their job profile and returns their contact information.
I need to return the result of Business Service 3 to the consumer. The consumer basically need to call the Proxy service with [Region] as the input value and the result should be the output of above Business service 3.
As I mentioned, I have WSDL for all the 3 Business Services, but, I do not have the WSDL for the Proxy Service. The Business Service WSDLs are all different and they do not match.
My question is it possible to achieve the above result without having a concrete WSDL for Proxy Service? Also, how can I go about solving this use case. I have gone through some articles that talk about Split-Join, and am really lost.
I really appreciate your kind reply on this.
Thanks in advance.
Regards,
Syama

Answer 1

You have multiple options:
1. Create a WSDL which has input similar to input of WS1 (only Region as input) and an output similar to output of WS3.
Create Proxy Service based on this WSDL. Then call all the thee business services one after the other and doing transformations/assigns as needed after each call. Finally map the result of BS3 to the similar output of your new WSDL on which the Proxy service is based.
2. Create an Any XML type of web service. Create a schema which has two elements, one for input and one for output. Input containing only Region and output containing all the details. All consumers need to send request according to input defined in schema and expect output defined in schema. Its similar to creating the WSDL but can be used in case your consumer do not want to call a Web Service but want to call an XML API over HTTP. Rest will be same as option 1.
Split join is needed to make calls in parallel, it wont be usable in your use case unless you expect a list og regions in the same request for each of which you need to gather same information by calling three services.