Fiori approve purchase order - custom error messages

[maxh]

Hi there,

we are trying to add some additional checks to the OData service related to the Fiori approve purchase order app. In case a check fails an error message should be displayed on the frontend (or at least be part of the HTTP response).

BADI: GBAPP_APV_PO_RDP
Interface: IF_GBAPP_EX_APV_PO_RDP
Method: CHANGE_SET_DECISION

The method CHANGE_SET_DECISION may raises an exception of type /IWBEP/CX_MGW_BUSI_EXCEPTION.

So basically that is what I´m trying to do:

CLASS /sie/ad_zcm_cl_fio_apv_check DEFINITION PUBLIC CREATE PUBLIC .
  PUBLIC SECTION.
    INTERFACES if_badi_interface .
    INTERFACES if_gbapp_ex_apv_po_rdp .
ENDCLASS.
CLASS /sie/ad_zcm_cl_fio_apv_check IMPLEMENTATION.
  METHOD if_gbapp_ex_apv_po_rdp~change_set_decision.
* some checks here
    RAISE EXCEPTION TYPE /iwbep/cx_mgw_busi_exception
      EXPORTING
        textid            = 
                   /iwbep/cx_mgw_busi_exception=>business_error_unlimited
        message_unlimited = 'some error message'.
  ENDMETHOD.
ENDCLASS.

Unfortunately the message is not part of the HTTP response. The message class and number are correct (business_error_unlimited) but instead of the message string the placeholder '&1' is shown.

{
  "error": {
    "code": "SY/530",
    "message": {
      "lang": "en",
      "value": "An exception was raised."
    },
    "innererror": {
      "application": {
        "component_id": "MM-PUR",
        "service_namespace": "/SAP/",
        "service_id": "GBAPP_POAPPROVAL",
        "service_version": "0001"
      },
      (...)
      "errordetails": [
        {
          "code": "/IWBEP/CM_MGW_RT/022",
          "message": "&1",
          "propertyref": "",
          "severity": "info",
          "target": ""
        },
        {
          "code": "/IWBEP/CX_MGW_BUSI_EXCEPTION",
          "message": "An exception was raised.",
          "propertyref": "",
          "severity": "error",
          "target": ""
        }
      ]
    }
  }
}

The exception is catched in class CL_GBAPP_APV_PO_API method SET_DECISION.

TRY.
      CALL BADI lo_ext_badi_rdp->change_set_decision
       EXPORTING
         iv_workitem_id        = <fs_approval_decision>-workitem_id
         iv_pc_number          = <fs_approval_decision>-po_number
         iv_release_code       = lv_release_code
         iv_approval_text      = lv_approval_text
         iv_rejection_text     = lv_rejection_text
         iv_approval_string    = <fs_approval_decision>-approval_text
         iv_rejection_string   = <fs_approval_decision>-rejection_text
         iv_decision           = <fs_approval_decision>-decision
       IMPORTING
         ev_decision_processed = lv_decision_processed
         es_action_successful  = lv_action_successful
         ev_skip_wait          = lv_skip_wait
         ev_wait_loops         = lv_wait_loops.


    CATCH /iwbep/cx_mgw_busi_exception INTO lcx_badi.
      " get_text() returns the correct message but lv_msg is a single char
      lv_msg  = lcx_badi->get_text( ).
      " the method has a paramter lv_text_msg but it´s not used here
      lo_cmn_api->raise_exception_iwbep_business( iv_leading_msg = lv_msg ).ENDTRY.

So the question is:
What is the correct way to do retrieve a custom error message using the /IWBEP/CX_MGW_BUSI_EXCEPTION exception class?

[maxh · Accepted solution]

For my release this issue has been solved by note 2747538.