1. Determining the SAP Business Object and Its Key Fields
2. Defining the Interface Structure of the BAPI
3. Identifying the name of the function group, or if a function group does not exist already, planning a name for one.
All BAPIs belonging to one SAP Business Object should be stored as function modules in one function group. Ascertain whether a function group has already been created for the BAPIs of the SAP Business Object in question. If a function group does not already exist, then plan a name for the one to be created.
To ascertain the technical name of the Business Object, open the Business Object in the Business Object Repository (BOR), as described in Determining the SAP Business Object and Its Key Fields. To display further details, for example, the object type, double click the name of the Business Object.
4. Assigning a name to the function module
Choose a name that gives an indication of what the BAPI is used for. The naming convention is: BAPI_<Business Object name>_<method name>. For information about naming a method refer to Naming the Method in the BOR.
For example, in the case of a BAPI which reads details for the object type Creditor, the name of the associated function module is BAPI_CREDITOR_GETDETAIL.
Naming Parameters in the Function Module
Defining the format for passing the values in the function module interface.
5.Parameters must not be converted before they are passed to and from the BAPI interface. This is because BAPIs are programming interfaces and not end user interfaces. Exceptions are currency codes, ISO codes and fields with an internal key.
Specifying the Required Objects in ABAP Dictionary
Naming the Method in the BOR
Naming Parameters in the BOR 6. Generate the ALE interface from BDBG.