django1/django/core/files/uploadedfile.py

273 lines
8.6 KiB
Python

"""
Classes representing uploaded files.
"""
import os
import warnings
try:
from cStringIO import StringIO
except ImportError:
from StringIO import StringIO
from django.conf import settings
from django.core.files import temp as tempfile
__all__ = ('UploadedFile', 'TemporaryUploadedFile', 'InMemoryUploadedFile', 'SimpleUploadedFile')
# Because we fooled around with it a bunch, UploadedFile has a bunch
# of deprecated properties. This little shortcut helps define 'em
# without too much code duplication.
def deprecated_property(old, new, readonly=False):
def issue_warning():
warnings.warn(
message = "UploadedFile.%s is deprecated; use UploadedFile.%s instead." % (old, new),
category = DeprecationWarning,
stacklevel = 3
)
def getter(self):
issue_warning()
return getattr(self, new)
def setter(self, value):
issue_warning()
setattr(self, new, value)
if readonly:
return property(getter)
else:
return property(getter, setter)
class UploadedFile(object):
"""
A abstract uploaded file (``TemporaryUploadedFile`` and
``InMemoryUploadedFile`` are the built-in concrete subclasses).
An ``UploadedFile`` object behaves somewhat like a file object and
represents some file data that the user submitted with a form.
"""
DEFAULT_CHUNK_SIZE = 64 * 2**10
def __init__(self, name=None, content_type=None, size=None, charset=None):
self.name = name
self.size = size
self.content_type = content_type
self.charset = charset
def __repr__(self):
return "<%s: %s (%s)>" % (self.__class__.__name__, self.name, self.content_type)
def _get_name(self):
return self._name
def _set_name(self, name):
# Sanitize the file name so that it can't be dangerous.
if name is not None:
# Just use the basename of the file -- anything else is dangerous.
name = os.path.basename(name)
# File names longer than 255 characters can cause problems on older OSes.
if len(name) > 255:
name, ext = os.path.splitext(name)
name = name[:255 - len(ext)] + ext
self._name = name
name = property(_get_name, _set_name)
def chunks(self, chunk_size=None):
"""
Read the file and yield chucks of ``chunk_size`` bytes (defaults to
``UploadedFile.DEFAULT_CHUNK_SIZE``).
"""
if not chunk_size:
chunk_size = UploadedFile.DEFAULT_CHUNK_SIZE
if hasattr(self, 'seek'):
self.seek(0)
# Assume the pointer is at zero...
counter = self.size
while counter > 0:
yield self.read(chunk_size)
counter -= chunk_size
# Deprecated properties
filename = deprecated_property(old="filename", new="name")
file_name = deprecated_property(old="file_name", new="name")
file_size = deprecated_property(old="file_size", new="size")
chunk = deprecated_property(old="chunk", new="chunks", readonly=True)
def _get_data(self):
warnings.warn(
message = "UploadedFile.data is deprecated; use UploadedFile.read() instead.",
category = DeprecationWarning,
stacklevel = 2
)
return self.read()
data = property(_get_data)
def multiple_chunks(self, chunk_size=None):
"""
Returns ``True`` if you can expect multiple chunks.
NB: If a particular file representation is in memory, subclasses should
always return ``False`` -- there's no good reason to read from memory in
chunks.
"""
if not chunk_size:
chunk_size = UploadedFile.DEFAULT_CHUNK_SIZE
return self.size > chunk_size
# Abstract methods; subclasses *must* define read() and probably should
# define open/close.
def read(self, num_bytes=None):
raise NotImplementedError()
def open(self):
pass
def close(self):
pass
def xreadlines(self):
return self
def readlines(self):
return list(self.xreadlines())
def __iter__(self):
# Iterate over this file-like object by newlines
buffer_ = None
for chunk in self.chunks():
chunk_buffer = StringIO(chunk)
for line in chunk_buffer:
if buffer_:
line = buffer_ + line
buffer_ = None
# If this is the end of a line, yield
# otherwise, wait for the next round
if line[-1] in ('\n', '\r'):
yield line
else:
buffer_ = line
if buffer_ is not None:
yield buffer_
# Backwards-compatible support for uploaded-files-as-dictionaries.
def __getitem__(self, key):
warnings.warn(
message = "The dictionary access of uploaded file objects is deprecated. Use the new object interface instead.",
category = DeprecationWarning,
stacklevel = 2
)
backwards_translate = {
'filename': 'name',
'content-type': 'content_type',
}
if key == 'content':
return self.read()
elif key == 'filename':
return self.name
elif key == 'content-type':
return self.content_type
else:
return getattr(self, key)
class TemporaryUploadedFile(UploadedFile):
"""
A file uploaded to a temporary location (i.e. stream-to-disk).
"""
def __init__(self, name, content_type, size, charset):
super(TemporaryUploadedFile, self).__init__(name, content_type, size, charset)
if settings.FILE_UPLOAD_TEMP_DIR:
self._file = tempfile.NamedTemporaryFile(suffix='.upload', dir=settings.FILE_UPLOAD_TEMP_DIR)
else:
self._file = tempfile.NamedTemporaryFile(suffix='.upload')
def temporary_file_path(self):
"""
Returns the full path of this file.
"""
return self._file.name
# Most methods on this object get proxied to NamedTemporaryFile.
# We can't directly subclass because NamedTemporaryFile is actually a
# factory function
def read(self, *args): return self._file.read(*args)
def seek(self, offset): return self._file.seek(offset)
def write(self, s): return self._file.write(s)
def __iter__(self): return iter(self._file)
def readlines(self, size=None): return self._file.readlines(size)
def xreadlines(self): return self._file.xreadlines()
def close(self):
try:
return self._file.close()
except OSError, e:
if e.errno == 2:
# Means the file was moved or deleted before the tempfile could unlink it.
# Still sets self._file.close_called and calls self._file.file.close()
# before the exception
return
else:
raise e
class InMemoryUploadedFile(UploadedFile):
"""
A file uploaded into memory (i.e. stream-to-memory).
"""
def __init__(self, file, field_name, name, content_type, size, charset):
super(InMemoryUploadedFile, self).__init__(name, content_type, size, charset)
self.file = file
self.field_name = field_name
self.file.seek(0)
def seek(self, *args, **kwargs):
self.file.seek(*args, **kwargs)
def open(self):
self.seek(0)
def read(self, *args, **kwargs):
return self.file.read(*args, **kwargs)
def chunks(self, chunk_size=None):
self.file.seek(0)
yield self.read()
def multiple_chunks(self, chunk_size=None):
# Since it's in memory, we'll never have multiple chunks.
return False
class SimpleUploadedFile(InMemoryUploadedFile):
"""
A simple representation of a file, which just has content, size, and a name.
"""
def __init__(self, name, content, content_type='text/plain'):
self.file = StringIO(content or '')
self.name = name
self.field_name = None
self.size = len(content or '')
self.content_type = content_type
self.charset = None
self.file.seek(0)
def from_dict(cls, file_dict):
"""
Creates a SimpleUploadedFile object from
a dictionary object with the following keys:
- filename
- content-type
- content
"""
return cls(file_dict['filename'],
file_dict['content'],
file_dict.get('content-type', 'text/plain'))
from_dict = classmethod(from_dict)