The File object
django.core.files module and its submodules contain built-in classes for basic file handling in Django.
Fileclass 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.
Fileobjects have the following attributes and methods:
The name of the file including the relative path from
The size of the file in bytes.
The underlying file object that this class wraps.
Be careful with this attribute in subclasses.
Some subclasses of
FieldFile, may replace this attribute with an object other than a Python file object. In these cases, this attribute may itself be a
Filesubclass (and not necessarily the same subclass). Whenever possible, use the attributes and methods of the subclass itself rather than the those of the subclass’s
The read/write mode for the file.
Open or reopen the file (which also does
modeargument allows the same values as Python’s built-in
When reopening a file,
modewill override whatever mode the file was originally opened with;
Nonemeans to reopen with the original mode.
Read content from the file. The optional
sizeis the number of bytes to read; if not specified, the file will be read to the end.
Iterate over the file yielding one line at a time.
Filenow 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
Iterate over the file yielding “chunks” of a given size.
chunk_sizedefaults 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.
Trueif the file is large enough to require multiple chunks to access all of its content give some
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.
Close the file.
In addition to the listed methods,
Fileexposes the following attributes and methods of its
xreadlines. If you are using Python 3, the
seekablemethod is also available.
seekablemethod was added.
ContentFileclass inherits from
File, but unlike
Fileit 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")
Django provides a built-in class specifically for images.
django.core.files.images.ImageFileinherits all the attributes and methods of
File, and additionally provides the following:
Width of the image in pixels.
Height of the image in pixels.
Additional methods on files attached to objects
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
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
contentargument must be an instance of either
Fileor of a subclass of
File, such as
Removes the file from the model instance and deletes the underlying file. If
True, the model’s
save()method will be called once the file is deleted.
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Licensed under the BSD License.