问题
My goal is to limit a FileField on a Django ModelForm to PDFs and Word Documents. The answers I have googled all deal with creating a separate file handler, but I am not sure how to do so in the context of a ModelForm. Is there a setting in settings.py I may use to limit upload file types?
回答1:
I handle this by using a clean_[your_field] method on a ModelForm. You could set a list of acceptable file extensions in settings.py to check against in your clean method, but there's nothing built-into settings.py to limit upload types.
Django-Filebrowser, for example, takes the approach of creating a list of acceptable file extensions in settings.py.
Hope that helps you out.
回答2:
Create a validation method like:
def validate_file_extension(value):
if not value.name.endswith('.pdf'):
raise ValidationError(u'Error message')
and include it on the FileField validators like this:
actual_file = models.FileField(upload_to='uploaded_files', validators=[validate_file_extension])
Also, instead of manually setting which extensions your model allows, you should create a list on your setting.py and iterate over it.
Edit
To filter for multiple files:
def validate_file_extension(value):
import os
ext = os.path.splitext(value.name)[1]
valid_extensions = ['.pdf','.doc','.docx']
if not ext in valid_extensions:
raise ValidationError(u'File not supported!')
回答3:
Validating with the extension of a file name is not a consistent way. For example I can rename a picture.jpg into a picture.pdf and the validation won't raise an error.
A better approach is to check the content_type of a file.
Validation Method
def validate_file_extension(value):
if value.file.content_type != 'application/pdf':
raise ValidationError(u'Error message')
Usage
actual_file = models.FileField(upload_to='uploaded_files', validators=[validate_file_extension])
回答4:
An easier way of doing it is as below in your Form
file = forms.FileField(widget=forms.FileInput(attrs={'accept':'application/pdf'}))
回答5:
For a more generic use, I wrote a small class ExtensionValidator
that extends Django's built-in RegexValidator
. It accepts single or multiple extensions, as well as an optional custom error message.
class ExtensionValidator(RegexValidator):
def __init__(self, extensions, message=None):
if not hasattr(extensions, '__iter__'):
extensions = [extensions]
regex = '\.(%s)$' % '|'.join(extensions)
if message is None:
message = 'File type not supported. Accepted types are: %s.' % ', '.join(extensions)
super(ExtensionValidator, self).__init__(regex, message)
def __call__(self, value):
super(ExtensionValidator, self).__call__(value.name)
Now you can define a validator inline with the field, e.g.:
my_file = models.FileField('My file', validators=[ExtensionValidator(['pdf', 'doc', 'docx'])])
回答6:
I use something along these lines (note, "pip install filemagic" is required for this...):
import magic
def validate_mime_type(value):
supported_types=['application/pdf',]
with magic.Magic(flags=magic.MAGIC_MIME_TYPE) as m:
mime_type=m.id_buffer(value.file.read(1024))
value.file.seek(0)
if mime_type not in supported_types:
raise ValidationError(u'Unsupported file type.')
You could probably also incorporate the previous examples into this - for example also check the extension/uploaded type (which might be faster as a primary check than magic.) This still isn't foolproof - but it's better, since it relies more on data in the file, rather than browser provided headers.
Note: This is a validator function that you'd want to add to the list of validators for the FileField model.
来源:https://stackoverflow.com/questions/6460848/how-to-limit-file-types-on-file-uploads-for-modelforms-with-filefields