How To Deploy Zip Files (or Other Binaries) Trough Cgi In Python?

I'm coding a small website with Python and CGI where users can upload zip files and download files uploaded by other users. Currently I'm able to upload correctly the zip's, but I

Solution 1:

You need to print an empty line after the headers, and you Content-disposition header is missing the type (attachment):

print("Content-type: application/octet-stream")
print("Content-Disposition: attachment; filename=%s.zip" %(filename))
print()

You may also want to use a more efficient method of uploading the resulting file; use shutil.copyfileobj() to copy the data to sys.stdout.buffer:

from shutil import copyfileobj
import sys

print("Content-type: application/octet-stream")
print("Content-Disposition: attachment; filename=%s.zip" %(filename))
print()

withopen('../../data/code/' + filename + '.zip','rb') as zipfile:
    copyfileobj(zipfile, sys.stdout.buffer)

You should not use print() for binary data in any case; all you get is b'...' byte literal syntax. The sys.stdout.buffer object is the underlying binary I/O buffer, copy binary data directly to that.

Solution 2:

The header is malformed because, for some reason, Python sends it after sending the file.

What you need to do is flush stdout right after the header:

sys.stdout.flush()

Then put the file copy