error download file api to vue browser

[danzf]

func (h *BookingMuseumHandler) DownloadExcels(c echo.Context) error {

data, _, err := h.bookingUcase.Fetch(ctx, au, &params)
if err != nil {
    return err
}

// Prepare the response data
pubRes := []domain.ListBookingMuseumDataResponse{}
for _, row := range data {
    res := domain.ListBookingMuseumDataResponse{
        ID:                row.ID,
        Nama:              row.PengunjungBookings.Nama,
        Email:             row.PengunjungBookings.Email,
        Kategori:          row.KategoriBookings.Nama,
        Sesi:              row.SesiBookings.Nama,
        JumlahPengunjung:  row.JumlahPengunjung,
        TanggalBerkunjung: row.TanggalBerkunjung,
        Dokumen:           row.DocBookings.Doc,
        BuktiBayarBookings: row.BuktiBayarBookings.Bukti,
        Status:            row.Status,
    }

    pubRes = append(pubRes, res)
}


// Create a new Excel file
f := excelize.NewFile()
index, err := f.NewSheet("Booking Museum")
if err != nil {
    return err
}
f.SetActiveSheet(index)
// Simpan file sementara di server untuk debugging

// Set header
headers := []string{
    "ID", "Nama", "Email", "Kategori", "Sesi", "Jumlah Pengunjung", "Tanggal Berkunjung", "Dokumen", "Bukti Bayar", "Status",
}
for col, header := range headers {
    f.SetCellValue("Booking Museum", fmt.Sprintf("%s1", string('A'+col)), header)
}

// Write data to Excel file
for i, res := range pubRes {
    f.SetCellValue("Booking Museum", fmt.Sprintf("A%d", i+2), strconv.FormatInt(res.ID, 10))
    f.SetCellValue("Booking Museum", fmt.Sprintf("B%d", i+2), res.Nama)
    f.SetCellValue("Booking Museum", fmt.Sprintf("C%d", i+2), res.Email)
    f.SetCellValue("Booking Museum", fmt.Sprintf("D%d", i+2), res.Kategori)
    f.SetCellValue("Booking Museum", fmt.Sprintf("E%d", i+2), res.Sesi)
    f.SetCellValue("Booking Museum", fmt.Sprintf("F%d", i+2), strconv.FormatInt(res.JumlahPengunjung, 10))
    f.SetCellValue("Booking Museum", fmt.Sprintf("G%d", i+2), res.TanggalBerkunjung)
    f.SetCellValue("Booking Museum", fmt.Sprintf("H%d", i+2), res.Dokumen)
    f.SetCellValue("Booking Museum", fmt.Sprintf("I%d", i+2), res.BuktiBayarBookings)
    f.SetCellValue("Booking Museum", fmt.Sprintf("J%d", i+2), res.Status)
}
if err := f.SaveAs("temp_booking_museum.xlsx"); err != nil {
	return err
}
buf := new(bytes.Buffer)
if err := f.Write(buf); err != nil {
	return c.JSON(500, "Failed to write Excel data to memory")
}

// Debugging: Periksa ukuran buffer
fmt.Println("Buffer size:", buf.Len())  // Pastikan ukuran file lebih besar dari 0
fmt.Printf("File size before sending: %d bytes\n", len(buf.Bytes()))

// Pastikan kita mengirimkan data dalam bentuk binary (Blob)
c.Response().Header().Set("Content-Disposition", "attachment; filename=booking_data.xlsx")
c.Response().Header().Set("Content-Type", "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet")
c.Response().Header().Set("Cache-Control", "no-store, no-cache, must-revalidate, proxy-revalidate")
c.Response().Header().Set("Pragma", "no-cache")
c.Response().Header().Set("Transfer-Encoding", "chunked")

// Kirimkan data dalam bentuk byte array (Blob)
return c.Blob(200, "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet", buf.Bytes())
}

     echo/v4 v4.11.3
excelize/v2 v2.9.0 
hasil dari pemanggilan api