Python CGI脚本IOError破管

Question

我有一个旧的基于Python的网页表单，我正在更新它，让它使用GPG来加密，而不是使用一个已经不再支持的Python包。当我通过命令行调用这个脚本时，一切都很好，但通过网页浏览器和CGI调用时却出现了一个错误：IOError: [Errno 32] Broken pipe。这个错误在我使用gnupg包或者直接通过子进程与gpg通信时都会出现。

版本信息：

Python 2.4.1 
gnupg 0.2.2 (python GPG wrapper)
Apache/2.2.9 
gpg 1.4.9

这里有一个简化的脚本：

#!/usr/bin/python 

import sys
# send python tracebacks out to the web browser
sys.stderr = sys.stdout
import gnupg
gpg = gnupg.GPG()
gpgkey = 'np'
message = 'Our secret message!'
print "Content-type: text/html\r\n"
print '''<html><head><title>Test GPG access via cgi</title>
          </head><body><pre>'''
print 'message in the clear:'
print message
encrypted = str(gpg.encrypt(message, 'np'))
print 'message encrypted:' 
print encrypted
print '''</pre></body></html>'''sf

当通过命令行调用上面的脚本时，它运行得很好，但通过CGI调用时却产生了以下错误：

message in the clear:
Our secret message!
Traceback (most recent call last):
  File "/home/dkmaster/www/nickads/secure-cgi/gpgtest.py", line 23, in 
    encrypted = str(gpg.encrypt(message, 'np'))
  File "/home/dkmaster/www/nickads/secure-cgi/gnupg.py", line 517, in encrypt
    return self.encrypt_file(StringIO(data), recipients, **kwargs)
  File "/home/dkmaster/www/nickads/secure-cgi/gnupg.py", line 467, in encrypt_file
    self._handle_io(args, file, result, passphrase=passphrase)
  File "/home/dkmaster/www/nickads/secure-cgi/gnupg.py", line 201, in _handle_io
    _copy_data(file, stdin)
  File "/home/dkmaster/www/nickads/secure-cgi/gnupg.py", line 75, in _copy_data
    outstream.write(data)
IOError: [Errno 32] Broken pipe

我还尝试直接通过子进程与GPG通信，而不是使用gnupg模块。

#!/usr/bin/python

import sys
import subprocess
sys.stderr = sys.stdout
print "Content-type: text/html\r\n"
print '''<html><head><title>Test subprocess via cgi</title>
           </head><body><pre>'''

plain_text = 'the quick fox ' * 10
print plain_text
gpgCommand = "/usr/bin/gpg --quiet -a -e -r 'np' "
gpgProcess = subprocess.Popen(
                      gpgCommand,
                      stdin=subprocess.PIPE, 
                      stdout=subprocess.PIPE, 
                      stderr=subprocess.PIPE, 
                      shell=True
                      )
encrypted_text = gpgProcess.communicate(plain_text)[0]
print encrypted_text

同样，这在命令行中运行良好，但通过CGI调用时会产生类似的错误：

Traceback (most recent call last):
  File "/home/dkmaster/www/nickads/secure-cgi/subprocesstest.py", line 20, in 
    encrypted_text = gpgProcess.communicate(plain_text)[0]
  File "/usr/lib/python2.5/subprocess.py", line 670, in communicate
    return self._communicate(input)
  File "/usr/lib/python2.5/subprocess.py", line 1220, in _communicate
    bytes_written = self._write_no_intr(self.stdin.fileno(), buffer(input, input_offset, 512))
  File "/usr/lib/python2.5/subprocess.py", line 999, in _write_no_intr
    return os.write(fd, s)
OSError: [Errno 32] Broken pipe

那么，我该如何修复CGI中的管道问题呢？

gpg subprocess cgi encryption gnupg IOError broken pipe web form

Python CGI脚本IOError破管

2 个回答

撰写回答