Message Mapping - To Retrieve IDoc No. using Meesage ID

Question

Hi Experts,
In a scenario where in File will be sent from Third Party to SAP which contains a Message ID, which is in reference to the acknowledgement of IDOC sent from SAP to Third Party.
Now what I need to find out is using this Message ID I need to Retrieve IDOC no. from the payload which was sent to third party in order to update the status of IDOC in SAP. So I suppose I need to write some user defined function and which will fetch the information from SAP PI tables.
So can you please guide me on what are the tables I can refer to have the IDoc No. from the payload and as I am not aware of writing UDF, it will be very useful if you provide me sample code for the same which I can refer in similar kind of case.
Please let me know if you need any clarification
Regards,
Nitin Patil

Answer 1

Hi Nitin,
You can create a UDF with following code.Pass Msgid as an input to this UDF.
Channel channel = LookupService.getChannel("ABCCLNT020","CC_RFC_Receiver");
RfcAccessor accessor = LookupService.getRfcAccessor(channel);
String rfcxml ="<ns0:Z_ZBXI_GET_IDOC_NUM xmlns:ns0=\"urn:sap-com:document:sap:rfc:functions\">" +
"<I_MSGID>"+ MSGID + "</I_MSGID>" +
"</ns0:Z_ZBXI_GET_IDOC_NUM> "  ;
InputStream inputStream =new ByteArrayInputStream(rfcxml.getBytes());
XmlPayload payload = LookupService.getXmlPayload(inputStream);
Payload rfcOutPayload = accessor.call(payload);
InputStream in = rfcOutPayload.getContent();
ByteArrayOutputStream out = new ByteArrayOutputStream(1024);
byte[] buffer = new byte[1024];
for (int read = in.read(buffer); read > 0; read = in.read(buffer)) {
out.write(buffer, 0, read);
String content = out.toString();
int Start_Index , End_Index ;
Start_Index = out.toString().indexOf("<E_DOCNUM>") + 10;
End_Index = out.toString().indexOf("</E_DOCNUM>") ;
String DOCNUM = out.toString().substring(Start_Index , End_Index);
return DOCNUM;
catch(Exception e)
     throw new RuntimeException("Exception : "+e);
This FM has to be created in R/3:
FUNCTION Z_ZBXI_GET_IDOC_NUM.
""Local Interface:
*"  IMPORTING
*"     VALUE(I_MSGID) TYPE  IDOCCARKEY
*"  EXPORTING
*"     VALUE(E_DOCNUM) TYPE  EDI_DOCNUM
DATA: lv_arckey(52) type c,
lv_docnum TYPE EDI_DOCNUM,
lv_key like edidc-arckey,
lv_sys_id like sy-sysid,
lv_des_id type char10.
lv_sys_id = sy-sysid.
lv_arckey = i_msgid.
if lv_sys_id = 'ABCDev'.
lv_des_id = 'DEVCLNT010'.
elseif lv_sys_id = 'ABCTest'.
lv_des_id = 'TSTCLNT010'.
elseif lv_sys_id = 'ABCPrd'.
lv_des_id = 'PRDCLNT010'.
Endif.
shift lv_arckey by 20 places right.
select single DOCNUM from EDIDC into lv_docnum where ARCKEY = lv_arckey.
if sy-subrc = 0.
e_docnum = 0.
else.
e_docnum = 1.
endif.
ENDFUNCTION.
Let us know if it works.
Thanks.
Regards,
Shweta