ServiceNow DataStream parse error "com.snc.process_flow.stream.SplittingDatastream"

[ponmudi]

I am facing an error while using DataStream action during Parser step.

Error:attached

class java.lang.String cannot be cast to class com.snc.process_flow.stream.SplittingDatastream (java.lang.String is in module java.base of loader 'bootstrap'; com.snc.process_flow.stream.SplittingDatastream is in unnamed module of loader

According to my Data stream use case, i want to call REST API with the REST Step, and i will be downloading an CSV File as a response body. I would want to parse the file and format it, update in a staging table.

my line of code in the parser step looks like this.

    (function parse(request, response) {

var csvContent = request.body.data;

gs.info ('CSV Data' + csvContent);

if (!csvContent || typeof csvContent !== 'string') {

        throw new Error("Expected CSV content as string in request.body.data");

    }

var lines = csvContent.split('\n');

    var rawHeader = lines[0].split(',');

    var header = [];

    for (var h = 0; h < rawHeader.length; h++) {

        header.push(rawHeader[h].replace(/"/g, '').trim());

    }

    var fieldMap = {

        'binary.name': 'Binaryname',

        'binary.last_seen': 'Lastused',

        'binary.product_name': 'Productname',

        'device.name': 'Devicename',

        'user.name': 'Username',

        'device.hardware.model': 'Devicehardwaremodel',

        'device.hardware.type': 'Devicehardwaretype',

    };

    for (var i = 1; i < lines.length; i++) {

        var row = lines[i].trim();

        if (!row) continue;

        var fields = row.split(',');

        var record = {};

        for (var j = 0; j < header.length; j++) {

            var csvHeader = header[j].trim();

            var fieldName = fieldMap[csvHeader];

            var fieldValue = fields[j] ? fields[j].replace(/"/g, '').trim() : '';

            if (fieldName) {

                record[fieldName] = fieldValue;

            }

        }

if (Object.keys(record).length > 0) {

        response.stream.write(record); // ✅ This is an object, not a string

    }

    }

})(request, response);

and i will attach the datastream steps.
I don't need a splitter step because my output or responsebody from rest step is a  CSV file and splitter step only supports either jso/xml format.

My question is, Not using splitter step will cause any issues like the error that i highlighted? or is it mandatory to have splitter step?

From google source, according to the error, it says, its expecting  a string!!
So, i have only possibility to get the API Call to download a CSV file.
Is there any way or code suggestions to read/convert my response body into String before i parse? or any experts of data stream, help me with the situation!!