Integration Server 10.7 | Web Services Developer’s Guide | SOAP Message Exchange Patterns | How the MEP Type Affects the SOAP Response a Provider Returns
 
How the MEP Type Affects the SOAP Response a Provider Returns
At run time, a web service operation’s MEP type dictates the SOAP response that a provider web service descriptor returns.
*For In-Out MEP, the Pre-8.2 compatibility mode property is a factor in the type of response a provider returns.
*When the Pre-8.2 compatibility mode property is false, the operation will only use In-Out MEP if it actually returns output. As a result, when the operation executes successfully, it returns a SOAP response that corresponds to the output defined for the operation. If an exception occurs, the operation returns a SOAP fault.
*When the Pre-8.2 compatibility mode property is true, although In-Out MEP is in use, an operation might not actually return a SOAP response.
*If an operation actually returns output, when the operation executes successfully, it returns a SOAP response that corresponds to the output defined for the operation. If an exception occurs, the operation returns a SOAP fault.
*If an operation does not actually return output, Integration Server still returns a SOAP response. If the operation executes successfully, Integration Server returns a SOAP response with an empty element in the SOAP body. If an exception occurs, a SOAP fault is returned.
This is the case for a service first provider when the service used for the web service descriptor does not have output parameters or for a WSDL first provider that does not include a <wsdl:output> element for an operation. In both cases, although the operation does not have output, because the Pre-8.2 compatibility mode property is true, Integration Server still uses In-Out MEP.
*For In-Only MEP, the Pre-8.2 compatibility mode property must be set to false.
When a client requests an In-Only MEP operation, the operation does not provide a SOAP response, even if an exception occurs.
*For Robust In-Only MEP, the Pre-8.2 compatibility mode property must be set to false.
When a client requests a Robust In-Only MEP operation, if the operation completes successfully, the operation does not return a response. However, if an exception occurs, the operation returns a SOAP fault.