SAP MII WSDL and REST best practices

Create a SAP MII transport map to execute SAP MII BLS transactions either through an XML-based WSDL or REST approach.

WSDL approach

WSDL is the recommended approach because it allows automatic retrieval of the input parameters of the SAP MII BLS transaction.

Transport and WSDL considerations: When WSDL security is enabled (the WSDLGenSecurityEnabled check box is selected on the SAP MII System Management link), user ID and password credentials on the SAP MII transport will allow the Transaction Server to access the WSDL.

Specifying a user ID and password on the SAP MII transport is optional; thus, the User and Password parameters can be left blank.

Transport map and WSDL considerations: When creating a SAP MII transport map, the SAP MII BLS transaction name (and optionally the folder name) must be specified.

When the Transaction Name parameter (and optionally, the Folder parameter) are filled in, the Query button can be used to retrieve the WSDL associated with that SAP MII BLS transaction. For more information, see Using Query to retrieve input and output parameters.

Depending on how the SAP MII BLS transactions are defined, the WSDL might expose both the input and output parameters on the To Enterprise section of the transport map.

In most cases, the input parameters are always exposed.

However, when the SAP MII BLS transaction returns its output parameters as XML, the WSDL will only return a stub for Rowset; thus, the output parameters must be added manually. To manually add the output parameters, you must have knowledge of the internal MII BLS transaction definitions. For more information, see Manually adding input and output parameters.

The REST approach

If the WSDL is not accessible or cannot be parsed, the Transaction Server can use the REST approach to build the URL and execute the SAP MII BLS transaction.

Transport map and REST considerations: When using the REST approach, both input and output parameters under the To Enterprise section of the transport map must be manually added. In addition, the name of the SAP MII BLS transaction XML parameter must be specified in the Output Parameter box.

Using the REST approach, only a single output parameter can be returned at one time. If the SAP MII BLS transaction explicitly lists output parameters (they are not returned as Rowset XML, but as individual elements), only one parameter can be returned and that is the parameter whose name is specified in the Output Parameter box. When the Output Parameter box is not filled in, then the SAP MII BLS transaction will not return any values to the Transaction Server.