Issue with RAP singleton instance handle validation and message propagation in RAP OData V4

[MKM]

Hi Experts,

We are working with a RAP Singleton OData V4 service that includes validations to restrict the SAVE operation using the FAILED structure under FOR VALIDATE ON SAVE.

APPEND VALUE #( %tky = ls_transactional_data-%tky ) TO  failed-ProjectSBUAlloc.
        APPEND VALUE #( %tky = ls_transactional_data-%tky
              %state_area = 'VALIDATE_PERCENT'
              %path-ProjectSBUAllocAll = CORRESPONDING #( ls_transactional_data )
              %element-distkey = if_abap_behv=>mk-on
              %msg     = new_message(

                  id       =  'ZTEST'
                  number   =  000
                  severity = if_abap_behv_message=>severity-error "CONV #( 'E')
                  v1       = 'Percentage value cannot be greater than 100'
                  )
        ) TO  reported-ProjectSBUAlloc.

This works as expected in the Eclipse ADT preview, but we are facing an issue when accessing it via the Fiori app.

The custom validation message does not appear on the UI; instead, only the framework error (RAP_DSP_REQUEST/023) is returned. Despite properly updating the FAILED AND REPORTED structures, the validation failures are not being correctly tied to the singleton instance, unlike regular entities.

The RAP framework is overriding the message, preventing it from being properly surfaced in the response.

What would be the best approach to ensure that our custom validation messages are correctly displayed in the UI when using RAP?

Any suggestions would be greatly appreciated!

[AZIZURRAHMAN]

Dear,

was this issue solved..? we are on S4HANA ON PREMISE SAP S/4HANA 2022 (SP/FP 02 (05/2023) )..

I am facing similar situation. my custom validation message is not displayed and only we get to see the message ("Resolve data inconsistencies to save changes.").. I have exactly same code when mapping to failed and reported.. I have issue in both FLP and Eclipse ADT preview.. I am using SAP RAP based OData v4 service in FE template ..any guidance would be helpful.. best regards,

[iliana]

Hi,

I wanted to ask if there has been any further progress or solution discovered for this issue? If you have any new insights, fixes, or workarounds, I would really appreciate if you could share them.

Thanks in advance for your help!

Best Retards