Abort UI action using script include

[Aasrita]

We have requirement of throwing an error on transform map when the column field names are wrong in Uploaded Excel sheet. We have the following script include.

var datasourceerror = Class.create();

datasourceerror.prototype = Object.extendsObject(AbstractAjaxProcessor, {

    datasourcefunction: function() {

        // var test = 0;

        var columns = [];

        var inc = new GlideRecord('sys_attachment');

        inc.addEncodedQuery('table_name=sys_data_source^table_sys_id=dadb0b1447110210279ceb02d16d434a');

        inc.orderByDesc('sys_created_on');

        inc.setLimit(1);

        inc.query();

        if (inc.next()) {

            var sysId = inc.getValue('sys_id');

            // gs.print(sysId);

        }

        var parser = new sn_impex.GlideExcelParser();

        var attachment = new GlideSysAttachment();

        var attachmentStream = attachment.getContentStream(sysId);

        parser.setSource(attachmentStream);

        var list_sheet_name = parser.getSheetNames();

        var requiredColumns = ['Number', 'Opened', 'Short description', 'Caller', 'Category', 'Assigned to', 'Assignment group', 'state(u_state)'];

        var missingColumns = [];

        for (i = 0; i < list_sheet_name.length; i++) {

            // gs.info('sheet name :' + list_sheet_name[i]);

            if (parser.parse()) {

                var headers = parser.getColumnHeaders();

                for (i = 0; i < headers.length; i++) {

                    if (headers.indexOf(requiredColumns[i]) === -1) {

                        missingColumns.push(requiredColumns[i]);

                        //if (headers[i] == 'Number' || headers[i] == 'Opened' || headers[i] == 'Short description' || headers[i] == 'Caller' || headers[i] == 'Category' || headers[i] == 'Assigned to'|| headers[i] == 'Assignment group' || headers[i]=='state(u_state)') {

                        count++;

                        // gs.print(headers[i]);

                    }

                }

            }

        }

        if (missingColumns.length > 0) {

            for (i = 0; i < missingColumns.length; i++) {

                columns.push(missingColumns[i]);

            }

            return JSON.stringify(columns);

        }

    },

    type: 'datasourceerror'

});

And the returned array is being checked on the Ui action 'Load All records'.

ar col = [];

col = new datasourceerror();

gs.log('hello123');

col.datasourcefunction();

gs.log(col);

if (col.length > 0) {

    //for (i = 0; i < col.length; i++) {

        gs.log('hello456');

        current.setAbortAction(true);

        gs.addErrorMessage('One/few of the column name is not matching with the data upload template. Please refer KB article  KB99999999 to fetch the right template. Missing/wrong columns:   ' + col.join(', '));

        gs.addErrorMessage('Test');

        action.setRedirectURL(current);

    //}

But the script in the UI action is not validating. Instead we keep the condition in UI policy it is working as expected.