Transform Map: How to display a custom error when a coalesce field is empty?

[Med99]

Hi everyone,

I’m working on a Transform Map where one of the fields is set as coalesce.
I would like to show a custom error message in import_log when this coalesce field is empty in the source data.

I tried adding this check in the onBefore script:

if (!source.u_code || source.u_code.toString().trim() === '') {
ignore = true;
source.sys_import_state_comment = "Obligatory field missing: Code";
}

However, this script is never executed when the coalesce field is empty.
Instead, I always get ServiceNow’s standard error:

"Unable to resolve the target record, coalesce field values are not present..." in sys_import_set_row

It seems the Transform Map engine throws this error before the onBefore script runs, so my message never appears.

How can I handle this situation and display my own validation message ?

Thanks in advance!

[Ankur Bawiskar]

@Med99 

try to use before insert BR on your staging table

something like this

(function executeRule(current, previous /*null when async*/ ) {
    if (!current.u_code || current.u_code.toString().trim() === '') {
        current.state = 'rejected';
        current.comments = 'Obligatory field missing: Code';
    }
})(current, previous);

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[Med99]

didn't work , I still get the servicenow standard message appearing