How to deploy zip files (or other binaries) trough cgi in Python?

情到浓时终转凉″ 提交于 2019-12-07 06:58:14

问题


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'm having some trouble to correctly send files to the user. My first approach was:

file = open('../../data/code/' + filename + '.zip','rb')

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

file.close()

But soon I realized that I had to send the file as binary, so I tried:

print("Content-type: application/octet-stream")
print("Content-Disposition: filename=%s.zip" %(filename))
print('Content-transfer-encoding: base64\r')
print( base64.b64encode(file.read()).decode(encoding='UTF-8') )

And different variants of it. It just doesn't works; Apache raises "malformed header from script" error, so I guess I should encode the file in some other way.


回答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()

with open('../../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.




回答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




回答3:


This is what worked for me, I am running Apache2 and loading this script via cgi. Python 3 is my language.

You may have to replace first line with your python 3 bin path.

#!/usr/bin/python3
import cgitb
import cgi
from zipfile import ZipFile
import sys

# Files to include in archive
source_file = ["/tmp/file1.txt", "/tmp/file2.txt"]

# Name and Path to our zip file.
zip_name = "zipfiles.zip"
zip_path = "/tmp/{}".format(zip_name)

with ZipFile( zip_path,'w' ) as zipFile:
    for f in source_file:
        zipFile.write(f);

# Closing File.
zipFile.close()

# Setting Proper Header.
print ( 'Content-Type:application/octet-stream; name="{}"'.format(zip_name) );
print ( 'Content-Disposition:attachment; filename="{}"\r\n'.format(zip_name) );

# Flushing Out stdout.
sys.stdout.flush()

bstdout = open(sys.stdout.fileno(), 'wb', closefd=False)
file = open(zip_path,'rb')
bstdout.write(file.read())
bstdout.flush()


来源:https://stackoverflow.com/questions/18339745/how-to-deploy-zip-files-or-other-binaries-trough-cgi-in-python

易学教程内所有资源均来自网络或用户发布的内容,如有违反法律规定的内容欢迎反馈
该文章没有解决你所遇到的问题?点击提问,说说你的问题,让更多的人一起探讨吧!