Python 3, Django 1.9+: Excel file creation and send on-the-fly with XlsxWriter & BytesIO

views.py

import xlsxwriter
from io import BytesIO
from django.http import StreamingHttpResponse
from django.views.generic import View


def get_foo_table_data():
    """
    Some table data 
    """
    return [
        [1, 2, 3],
        [4, 5, 6],
        [7, 8, 9],
    ]


class MyView(View):
    def get(self, request):
        data = get_foo_table_data()
        
        # create workbook with worksheet
        output = BytesIO()
        book = xlsxwriter.Workbook(output)
        sheet = book.add_worksheet()
        
        # fill worksheet with foo data
        for row, columns in enumerate(data):
            for column, cell_data in enumerate(columns):
                sheet.write(row, column, cell_data)
        
        book.close()  # close book and save it in "output"
        output.seek(0)  # seek stream on begin to retrieve all data from it

        # send "output" object to stream with mimetype and filename
        response = StreamingHttpResponse(
            output, content_type='application/vnd.openxmlformats-officedocument.spreadsheetml.sheet'
        )
        response['Content-Disposition'] = 'attachment; filename=foo.xlsx'
        return response