Get Packaging Material of a Product in EWM

Assumption: The relationship between the Product and its Packaging Specification is one-to-one.
Note: Multiple Pack. Spec. for a Product should be handled accordingly.

Report Code:

*&---------------------------------------------------------------------*
*& Report ZAG_GET_PMAT_PRODUCT
*&---------------------------------------------------------------------*
*& Developed by Arun Ganesh
*&---------------------------------------------------------------------*
REPORT zag_get_pmat_product.

*-> Selection Screen
PARAMETERS p_mat TYPE /scwm/de_matnr.

*-> Local Data Declarations
DATA: ls_content_query TYPE /scwm/s_ps_content_query,
      lt_ps_keys       TYPE /scwm/tt_ps_header_key,
      lv_severity      TYPE bapi_mtype,
      lt_return        TYPE bapirettab,
      lv_matid_16      TYPE /scwm/de_matid,
      lt_matid_tab     TYPE /scmb/mdl_matid_tab,
      lt_object        TYPE /scwm/tt_ps_object.

*-> Get Packaging Specifications of the Product
SELECT SINGLE matid "Secondary Index fetch
         FROM /sapapo/matkey
         INTO @DATA(lv_matid_22)
        WHERE matnr = @p_mat.
IF sy-subrc = 0.
  CALL FUNCTION '/SCMB/MDL_GUID_CONVERT'
    EXPORTING
      iv_guid22 = lv_matid_22
    IMPORTING
      ev_guid16 = lv_matid_16.
  IF lv_matid_16 IS NOT INITIAL.

    APPEND INITIAL LINE TO lt_matid_tab ASSIGNING FIELD-SYMBOL(<lfs_matid_tab>).
    <lfs_matid_tab>-matid = lv_matid_16.

    ls_content_query-matid = lt_matid_tab.

    CALL FUNCTION '/SCWM/API_PACKSPEC_GETLIST'
      EXPORTING
        is_content_query = ls_content_query
      IMPORTING
        et_ps_keys       = lt_ps_keys
        ev_severity      = lv_severity
        et_return        = lt_return.
    IF NOT lv_severity CA wmegc_severity_eax AND
      lt_ps_keys IS NOT INITIAL.
      CLEAR: lv_severity,
             lt_return.

*-> Get Pack. Spec. details
      CALL FUNCTION '/SCWM/API_PACKSPEC_READ'
        EXPORTING
          it_ps_id    = lt_ps_keys
        IMPORTING
          et_object   = lt_object
          ev_severity = lv_severity
          et_return   = lt_return.
      IF NOT lv_severity CA wmegc_severity_eax AND
         lt_object IS NOT INITIAL.
        READ TABLE lt_object ASSIGNING FIELD-SYMBOL(<lfs_object>)
                             INDEX 1.
        IF sy-subrc = 0.
          READ TABLE <lfs_object>-levels ASSIGNING FIELD-SYMBOL(<lfs_level>)
                                         INDEX 2. "2nd level read
          IF sy-subrc  = 0.
            WRITE <lfs_level>-hu_mat.
          ENDIF.
        ENDIF.
      ENDIF.
    ENDIF.
  ENDIF. "lv_matid_16 NOT INITIAL
ENDIF. "SELECT matid from /SAPAPO/MATKEY