Additional attributes for the attributes exchange / attribute transfer from SAP (attributes_from_sap.xml) can be realized via a BAdI-Implementation.
BAdI: /DSCSAG/ENH_DOC
Method: DOC_GET_ATTRIBS_AFTER
Simple example 1 for the BAdI-Implementation
DATA: ls_attribute TYPE /dscsag/doc_customer_attribs, lf_zusatz TYPE mara-zzusatz. CLEAR ls_attribute. SELECT zzusatz FROM mara INTO lf_zusatz WHERE matnr = material. ls_attribute-name = 'MARA-ZZUSATZ'. MOVE lf_zusatz TO ls_attribute-value. APPEND ls_attribute TO ct_customerattributes.
Simple example 2 for the BAdI-Implementation
DATA ls_cust_attr TYPE /dscsag/doc_customer_attribs. FIELD-SYMBOLS: <ls_expression> TYPE /dscsag/doc_customer_attribs. IF is_documentkey-documenttype EQ 'NXM'. READ TABLE ct_expressions ASSIGNING <ls_expression> WITH KEY name = 'GEWICHT'. IF sy-uname EQ 0. CLEAR ls_cust_attr. ls_cust_attr-name = 'TB_WEIGHT'. ls_cust_attr-value = <ls_expression>-value. APPEND ls_cust_attr TO ct_customerattributes. ENDIF. ENDIF.