Rule Definition
BAPIs must not cause program terminations, they can only return a message (type A: termination message) in the return parameter. Messages of type E (error) and A (termination) cannot be output in the program, otherwise the BAPI will not be processed correctly and control may not be given back to the calling program.

Remediation
You must create a parameter named Return for every BAPI. This parameter returns exception messages or success messages to the calling program.

Violation Code Sample

FUNCTION BAPI_PO_GETDETAIL.
...
SELECT SINGLE * FROM EKKO WHERE EBELN EQ PURCHASEORDER.

IF SY-SUBRC NE 0.
    RAISE INCORRECT_PURCHASEORDER.
ENDIF.
...
ENDFUNCTION.

Fixed Code Sample

FUNCTION BAPI_PO_GETDETAIL.
...
SELECT SINGLE * FROM EKKO WHERE EBELN EQ PURCHASEORDER.

IF SY-SUBRC NE 0.
    PERFORM FILL_BAPIRETURN TABLES RETURN
        USING 'E'
                   'W5'
                   '107'
                   PURCHASEORDER.
    EXIT.
ENDIF.
...
ENDFUNCTION.

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