behaviour of date of files when writing a zip file python

Question

I want to write txt files and save them to a zipfile

The problem I'm facing - whenever I extract the file, the dates of the files are all 1 Jan 1980

here's the code

from zipfile import ZipFile

files = ['A.txt', 'B.txt', 'C.txt']

with ZipFile('example.zip','w') as myzip:
    for file_name in files:
        with myzip.open(file_name, 'w') as file:
            file.write('example text'.encode())

I would like to understand if this is expected behaviour and if there is anything I can do in the code so that the dates are correct.

Answer 1

To use ZipFile.open(, mode='w') adding a virtual file (which means it does not really exist on the disk), and importantly have a reasonable datetime tied to it (rather than some broken weird date back to 1980-01-01 or so)... — You may have a try to construct a ZipInfo model specified with date_time and use the model as the name argument to call ZipFile.open().

files = ['A.txt', 'B.txt', 'C.txt']

with zipfile.ZipFile(file='example.zip', mode='w', compression=zipfile.ZIP_DEFLATED) as fzip:
    for file_name in files:
        # create a ZipInfo model with date_time.
        file_info = zipfile.ZipInfo(
            filename=file_name,
            date_time=datetime.datetime.now().timetuple()[:6],
            # for demo purpose. may need carefully examine timezone in case of practice.
        )

        # important: explicitly set compress_type here to sync with ZipFile,
        # otherwise a bad default ZIP_STORED will be used.
        file_info.compress_type = fzip.compression

        # open() with ZipInfo instead of raw str as name to add the virtual file.
        with fzip.open(name=file_info, mode='w') as fbin:
            ...

BE CAREFUL: You have to explicitly set the ZipInfo model's compress_type attribute (to sync with ZipFile). Otherwise a default value compress_type=ZIP_STORED (which generally is a bad value) would be used! This attribute does take effect behind the scene but is not exposed by the constructor (__init__) of ZipInfo thus it could be easily got ignored.