django1/django/core/files/temp.py

85 lines
2.9 KiB
Python

"""
The temp module provides a NamedTemporaryFile that can be reopened in the same
process on any platform. Most platforms use the standard Python
tempfile.NamedTemporaryFile class, but Windows users are given a custom class.
This is needed because the Python implementation of NamedTemporaryFile uses the
O_TEMPORARY flag under Windows, which prevents the file from being reopened
if the same flag is not provided [1][2]. Note that this does not address the
more general issue of opening a file for writing and reading in multiple
processes in a manner that works across platforms.
Also note that the custom version of NamedTemporaryFile does not support the
full range of keyword arguments available in Python 2.6+ and 3.0+.
1: https://mail.python.org/pipermail/python-list/2005-December/336958.html
2: http://bugs.python.org/issue14243
"""
import os
import tempfile
from django.core.files.utils import FileProxyMixin
__all__ = ('NamedTemporaryFile', 'gettempdir',)
if os.name == 'nt':
class TemporaryFile(FileProxyMixin):
"""
Temporary file object constructor that supports reopening of the
temporary file in Windows.
Note that unlike tempfile.NamedTemporaryFile from the standard library,
__init__() does not support the 'delete' keyword argument in
Python 2.6+, or the 'delete', 'buffering', 'encoding', or 'newline'
keyword arguments in Python 3.0+.
"""
def __init__(self, mode='w+b', bufsize=-1, suffix='', prefix='',
dir=None):
fd, name = tempfile.mkstemp(suffix=suffix, prefix=prefix, dir=dir)
self.name = name
self.file = os.fdopen(fd, mode, bufsize)
self.close_called = False
# Because close can be called during shutdown
# we need to cache os.unlink and access it
# as self.unlink only
unlink = os.unlink
def close(self):
if not self.close_called:
self.close_called = True
try:
self.file.close()
except (OSError, IOError):
pass
try:
self.unlink(self.name)
except (OSError):
pass
@property
def closed(self):
"""
This attribute needs to be accessible in certain situations,
because this class is supposed to mock the API of the class
tempfile.NamedTemporaryFile in the Python standard library.
"""
return self.file.closed
def __del__(self):
self.close()
def __enter__(self):
self.file.__enter__()
return self
def __exit__(self, exc, value, tb):
self.file.__exit__(exc, value, tb)
NamedTemporaryFile = TemporaryFile
else:
NamedTemporaryFile = tempfile.NamedTemporaryFile
gettempdir = tempfile.gettempdir