Application Log

This article explains how to create your own application logging program in ABAP.
SAP provides standard functionality to write into as well as view the application log. This article will explain in detail how to create your own logging function module for application logging using standard SAP log facility. Two transaction code related to application logging are

• SLG0 -> Used to maintain the log object
• SLG1 -> Used to view the log

Desired Functionality in Project

When a program is run in background mode, all the error messages get logged into spool. However, in case of  project, the requirement is that a notification needs to be generated in Application Log corresponding to all such spools. Only one message needs to be logged into Application Log for the entire error messages generated in a particular program.

Configuration step

In this step create a log object.

1. Open transaction SLG0. An information message about cross-client table will come.
2. 2. Click the button "New Entries". Enter the name and description of your log object (say ZTESTLOG as object name and "Test Log" as object description) and save.

Development Step

The following standard function modules provided by SAP has been used to create the Z function module for logging.

• BAL_GLB_MSG_DEFAULTS_SET
• BAL_DB_SAVE
• BAL_LOG_MSG_ADD

Here are the steps:

1. Go to transaction SE11. Create a z-structure Z_LOG_MESSAGE having the following fields

2. Crate a message class say ZMESSAGE in transaction SE91 and a message 999 with four placeholder ( & ) as the text.

3. Go to transaction SE37. Create a function group say ZLOG

4. After the function group is created, create a function module in that group. Let is name it ZIU_MESSAGE_LOGGING.

Import parameters:
a. I_LOG_OBJECT type BALOBJ_D -> Application log: Object name (Application code)
b. I_EXTNUMBER type String -> Application Log: External ID

Export parameters: None
Changing parameters: None
Tables parameters:
T_LOG_MESSAGE type Z_LOG_MESSAGE
Exceptions:
LOG_HEADER_INCONSISTENT
LOGGING_ERROR

Paste the code below as the source code

ZIU_MESSAGE_LOGGINGFUNCTION ZIU_MESSAGE_LOGGING.
*"----------------------------------------------------------------------
""Local interface:
*" IMPORTING
*" REFERENCE(I_LOG_OBJECT) TYPE BALOBJ_D
*" REFERENCE(I_EXTNUMBER) TYPE STRING
*" TABLES
*" T_LOG_MESSAGE STRUCTURE Z_LOG_MESSAGE
*" EXCEPTIONS
*" LOG_HEADER_INCONSISTENT
*" LOGGING_ERROR
"--------------------------------------------------------------------- 
"DESCRIPTION: This function module is used insert messages in the application log
  CONSTANTS: c_message TYPE syst-msgid VALUE 'ZMESSAGE',
  c_999 TYPE syst-msgno VALUE '999'.
DATA:
l_log_handle TYPE balloghndl,
l_s_log TYPE bal_s_log,
l_dummy TYPE string,
l_ext_no TYPE bal_s_log-extnumber,
l_s_mdef TYPE bal_s_mdef.
IF t_log_message[] IS NOT INITIAL.
  l_s_log-object = i_log_object.
  l_ext_no = i_extnumber.
  l_s_log-extnumber = l_ext_no.
  "Create the log with header data
  CALL FUNCTION 'BAL_LOG_CREATE'
    EXPORTING
      i_s_log                 = l_s_log
    IMPORTING
      e_log_handle            = l_log_handle
    EXCEPTIONS
      log_header_inconsistent = 1
      OTHERS                  = 2.
  IF sy-subrc <> 0.
    CASE sy-subrc.
      WHEN 1.
        RAISE log_header_inconsistent.
      WHEN OTHERS.
        RAISE logging_error.
    ENDCASE.
  ENDIF.
  l_s_mdef-log_handle = l_log_handle.
  Set the default value
  CALL FUNCTION 'BAL_GLB_MSG_DEFAULTS_SET'
    EXPORTING
      i_s_msg_defaults = l_s_mdef
    EXCEPTIONS
      OTHERS           = 0.
 " Loop the message table and write the messages into the log
      LOOP AT t_log_message.
    "Use the message type ZMESSAGE and msg no 999
    "Issue the message in a dummy variable
          MESSAGE ID c_message TYPE t_log_message-msgty NUMBER c_999
          WITH t_log_message-msg_text_1 t_log_message-msg_text_2
          t_log_message-msg_text_3 t_log_message-msg_text_4
          INTO l_dummy.
    "The parameters set by message statement will be used
    "Add the message in the log
          PERFORM msg_add.
  ENDLOOP.

 " save logs in the database
  CALL FUNCTION 'BAL_DB_SAVE'
    EXPORTING
      i_save_all       = 'X'
    EXCEPTIONS
      log_not_found    = 1
      save_not_allowed = 2
      numbering_error  = 3
      OTHERS           = 4.
  IF sy-subrc <> 0.
    MESSAGE ID sy-msgid TYPE sy-msgty NUMBER sy-msgno
    WITH sy-msgv1 sy-msgv2 sy-msgv3 sy-msgv4.
  ENDIF.
ENDIF.
ENDFUNCTION.
"MSG_ADD
*--------------------------------------------------------------------
"FORM MSG_ADD
*--------------------------------------------------------------------
"Add the message to the log
-------------------------------------------------------------------
FORM msg_add.
DATA:
l_s_msg TYPE bal_s_msg.
"define data of message for Application Log
l_s_msg-msgty = sy-msgty.
l_s_msg-msgid = sy-msgid.
l_s_msg-msgno = sy-msgno.
l_s_msg-msgv1 = sy-msgv1.
l_s_msg-msgv2 = sy-msgv2.
l_s_msg-msgv3 = sy-msgv3.
l_s_msg-msgv4 = sy-msgv4.
"add this message to log file
"(I_LOG_HANDLE is not specified, we want to add to the default log.
"If it does not exist we do not care =>EXCEPTIONS log_not_found = 0)
CALL FUNCTION 'BAL_LOG_MSG_ADD'
  EXPORTING
    I_LOG_HANDLE  = i_s_msg
    =
    l_s_msg
  EXCEPTIONS
    log_not_found = 0
    OTHERS        = 1.
  IF sy-subrc <> 0.
    MESSAGE ID sy-msgid TYPE sy-msgty NUMBER sy-msgno
    WITH sy-msgv1 sy-msgv2 sy-msgv3 sy-msgv4.
  ENDIF.
ENDFORM.                    "
"Using the function module:
"In your ABAP program write the following code and use this function module ZIU_MESSAGE_LOGGING for logging.
" * Data declaration->
"Internal table for message logging
DATA: it_log_message TYPE STANDARD TABLE OF z_log_message,
wa_log_message TYPE z_log_message,
l_ext_number TYPE string.
Constants:
c_obj_zxiproxy TYPE balobj_d VALUE 'ZTESTLOG'.
"Now populate the internal table with the log messages as shown below. wa_log_message-
"msgty is the type of the message.
E -> Error, W -> Warning, S -> Success
"Logging code for insert message into log
CLEAR wa_log_message.
wa_log_message-msgty = 'E'. " Can use W or S
wa_log_message-msg_text_1 = < Message text 1>.
wa_log_message-msg_text_2 = < Message text 2>
wa_log_message-msg_text_3 = < Message text 3>
wa_log_message-msg_text_4 = < Message text 4>
Append the message into the internal table
APPEND wa_log_message TO it_log_message.
"At the end transfer the log message to the system log by calling function module ZIU_MESSAGE_LOGGING.
  "L_EXT_NUMBER will bt any string of your choice.
  "Function module ZIU_MESSAGE_LOGGING will do the logging
 " i_log_object is the object type (to be configrd using txn SLG0
  CALL FUNCTION 'ZIU_MESSAGE_LOGGING'
    EXPORTING
      i_log_object            = c_obj_zxiproxy
      i_extnumber             = l_ext_number
    TABLES
      t_log_message           = it_log_message
    EXCEPTIONS
      log_header_inconsistent = 1
      logging_error           = 2
      OTHERS                  = 3.
    IF sy-subrc <> 0.
      MESSAGE ID SY-MSGID TYPE SY-MSGTY NUMBER SY-MSGNO
      WITH SY-MSGV1 SY-MSGV2 SY-MSGV3 SY-MSGV4.
    ENDIF.
  ENDIF.
  "The logged messages can be viewed in transaction SLG1.
  "For filtering the messages use the Object type.