File object¶The django.core.files module and its submodules contain built-in classes
for basic file handling in Django.
File class¶File(file_object)[source]¶The File class is a thin wrapper around a Python
file object with some Django-specific additions.
Internally, Django uses this class when it needs to represent a file.
File objects have the following attributes and methods:
name¶The name of the file including the relative path from
MEDIA_ROOT.
size¶The size of the file in bytes.
file¶The underlying file object that this class wraps.
mode¶The read/write mode for the file.
open(mode=None)[source]¶Open or reopen the file (which also does File.seek(0)).
The mode argument allows the same values
as Python’s built-in open().
When reopening a file, mode will override whatever mode the file
was originally opened with; None means to reopen with the original
mode.
read(num_bytes=None)¶Read content from the file. The optional size is the number of
bytes to read; if not specified, the file will be read to the end.
__iter__()[source]¶Iterate over the file yielding one line at a time.
File now uses universal newlines. The following are
recognized as ending a line: the Unix end-of-line convention
'\n', the Windows convention '\r\n', and the old Macintosh
convention '\r'.
chunks(chunk_size=None)[source]¶Iterate over the file yielding “chunks” of a given size. chunk_size
defaults to 64 KB.
This is especially useful with very large files since it allows them to be streamed off disk and avoids storing the whole file in memory.
multiple_chunks(chunk_size=None)[source]¶Returns True if the file is large enough to require multiple chunks
to access all of its content give some chunk_size.
write(content)¶Writes the specified content string to the file. Depending on the
storage system behind the scenes, this content might not be fully
committed until close() is called on the file.
In addition to the listed methods, File exposes
the following attributes and methods of its file object:
encoding, fileno, flush, isatty, newlines,
read, readinto, readlines, seek, softspace, tell,
truncate, writelines, xreadlines. If you are using
Python 3, the seekable method is also available.
The seekable method was added.
ContentFile class¶ContentFile(File)[source]¶The ContentFile class inherits from File,
but unlike File it operates on string content
(bytes also supported), rather than an actual file. For example:
from __future__ import unicode_literals
from django.core.files.base import ContentFile
f1 = ContentFile("esta sentencia está en español")
f2 = ContentFile(b"these are bytes")
ImageFile class¶Any File that is associated with an object (as with Car.photo,
below) will also have a couple of extra methods:
File.save(name, content, save=True)¶Saves a new file with the file name and contents provided. This will not
replace the existing file, but will create a new file and update the object
to point to it. If save is True, the model’s save() method will
be called once the file is saved. That is, these two lines:
>>> car.photo.save('myphoto.jpg', content, save=False)
>>> car.save()
are equivalent to:
>>> car.photo.save('myphoto.jpg', content, save=True)
Note that the content argument must be an instance of either
File or of a subclass of File, such as
ContentFile.
File.delete(save=True)¶Removes the file from the model instance and deletes the underlying file.
If save is True, the model’s save() method will be called once
the file is deleted.
May 02, 2016