Saving openpyxl file via text and filestream

Question

I\'m building OpenPyXL into an application that expects a string containing the content of the excel file, for it to write via file stream.

From my investigation into th

Answer 1

from openpyxl import Workbook
from io import BytesIO

rows = [[1,2], [3,4]]

book = Workbook()
sheet = book.active

for row in rows:
    sheet.append(row)

io = BytesIO
book.save(io)

content = io.getValue()

return Response(
    content,
    mimetype=magic.from_buffer(content, mime=True),
    headers={
    'Content-Disposition': 'attachment;filename=' + 'test.xlsx'}
)

Answer 2

What about using a StringIO object to save the contents of the file:

from openpyxl.workbook import Workbook
from StringIO import StringIO

output = StringIO()
wb = Workbook()
wb.save(output)
print output.getvalue()

The string you're looking for is what is being printed in the last line of this example.

Answer 3

In openpyxl 2.6 calling the save_virtual_workbook method issues the following warning:

DeprecationWarning: Call to deprecated function save_virtual_workbook (Use a NamedTemporaryFile).

At some point save_virtual_workbook will be removed from openpyxl.

In Python 3 typical usage to save an openpyxl workbook to a filestream becomes:

from io import BytesIO
from tempfile import NamedTemporaryFile
from openpyxl import Workbook

wb = Workbook()
with NamedTemporaryFile() as tmp:
    wb.save(tmp.name)
    output = BytesIO(tmp.read())

After looking at the implementation of the WorkBook save method, the 'filename' is sent straight to ZipFile which accepts a path or file-like object so there is no need for a NamedTemporaryFile and simply use in-memory BytesIO:

from io import BytesIO
from openpyxl import Workbook

wb = Workbook()
virtual_workbook = BytesIO()
wb.save(virtual_workbook)

# now use virtual_workbook to send to a stream; email attachment, etc

Answer 4

A compatible implementation with save_virtual_workbook deprecated since version 2.6:

from io import BytesIO
from tempfile import NamedTemporaryFile


def save_virtual_workbook(workbook):
    with NamedTemporaryFile() as tf:
        workbook.save(tf.name)
        in_memory = BytesIO(tf.read())
        return in_memory.getvalue()

Answer 5

jcollado's answer is actually valid, but there is also a function (sadly not documented yet) called "save_virtual_workbook" in openpyxl.writer.excel that will take your workbook and return the workbook as a string:

from openpyxl.workbook import Workbook
from openpyxl.writer.excel import save_virtual_workbook

wb = Workbook()
print save_virtual_workbook(wb)

What you're looking for is the string returned by save_virtual_workbook()