Excel Create and Download Frappe (ERPNext)

excel_download_client.js

frappe.ui.form.on('Sevkiyat', {
	refresh: function(frm) {
        frm.add_custom_button('Çeki Listesi Oluştur', async function() {
            let columns = ["Batch", "Item Code", "Roll ID", "Customer", "Sales Order", "Net Weight [Kg]", "Gross Weight [Kg]", "Meter [cm]", "Width [cm]", "Diameter [cm]"];
            
            let data = [];
            for(let dItemIndex = 0; dItemIndex < frm.doc.shipment_detail.length; dItemIndex++) {
                let docBatch = await frappe.db.get_doc("Batch", frm.doc.shipment_detail[dItemIndex].batch);
                console.log(docBatch.reference_name);
                let docWO = await frappe.db.get_value("Stock Entry", docBatch.reference_name, "work_order");
                console.log(docWO);
                data.push([
                    docWO.message.work_order, frm.doc.shipment_detail[dItemIndex].item_code, frm.doc.shipment_detail[dItemIndex].batch,
                    frm.doc.customer, frm.doc.shipment_detail[dItemIndex].sales_order, 
                    docBatch.ld_net_weight, docBatch.gross_weight, docBatch.meter, docBatch.length, docBatch.diameter
                    ]
                );
            }
            
            open_url_post(
				'/api/method/jetorme.jo_utils.download_excel_file',
				{
				    columns: JSON.stringify(columns),
					data: JSON.stringify(data)
				}
			);
        });
    }
});

excel_download_server.py

@frappe.whitelist()
def download_excel_file(columns, data, excel_filename = "test.xlsx", sheet_name = "Generated by Fox"):
	#This method will be used to generate excel files from data
	from frappe.utils.xlsxutils import make_xlsx
	from frappe.desk.query_report import build_xlsx_data
	from frappe.utils.csvutils import UnicodeWriter
	import csv
	import os

	columns = json.loads(columns)
	data = json.loads(data)

	writer = UnicodeWriter()
	writer.writerow(columns)
	for item in data:
		writer.writerow(item)

	filename = frappe.generate_hash("", 10)
	with open(filename, "wb") as f:
		f.write(cstr(writer.getvalue()).encode("utf-8"))
	f = open(filename)
	reader = csv.reader(f)

	xlsx_file = make_xlsx(reader, sheet_name)

	f.close()
	os.remove(filename)

	# write out response as a xlsx type
	frappe.response["filename"] = excel_filename#"coa_importer_template.xlsx"
	frappe.response["filecontent"] = xlsx_file.getvalue()
	frappe.response["type"] = "binary"