Python3: Write csv directly to zipfile gives TypeError

Question

I want to create a csv-file within a zipfile - without using temp files or so. But the zipfile-handler seems to need a byte-object. The csv-handler seems to output str-only.

What is the best / common way to handle this?

test.py:

import zipfile
import csv

with zipfile.ZipFile("test.zip",mode='w',compression=zipfile.ZIP_DEFLATED) as zip:
    with zip.open('itemgroups.csv', mode='w') as csvfile:
        csvoutput = csv.writer(csvfile, delimiter=',', quotechar='"', quoting=csv.QUOTE_MINIMAL)
        csvoutput.writerow(['id', 'value'])

~$ python3 test.py
Traceback (most recent call last):
  File "test.py", line 7, in <module>
    csvoutput.writerow(['id', 'value'])
  File "/usr/lib/python3.7/zipfile.py", line 1094, in write
    self._crc = crc32(data, self._crc)
TypeError: a bytes-like object is required, not 'str'

Answer 1

I thought about it and created an adapter class:

class zipadapter:
    def __init__(self, zipfile):
        self.zipfile = zipfile
    def write(self, string):
        self.zipfile.write(string.encode())

I use it this way:

with zipfile.ZipFile("test.zip",mode='w',compression=zipfile.ZIP_DEFLATED) as zip:
    with zip.open('itemgroups.csv', mode='w') as csvfile:
        csvstrfile = zipadapter(csvfile)
        csvoutput = csv.writer(csvstrfile, delimiter=',', quotechar='"', quoting=csv.QUOTE_MINIMAL)
        csvoutput.writerow(['id', 'value'])

And... it works. Elegant? I don't know. Best way? I doubt that - if you have better ideas, don't hesitate to answer ;-)