只接受服务器端FileField中的某个文件类型

How can I restrict FileField to only accept a certain type of file (video, audio, pdf, etc.) in an elegant way, server-side?

如何限制FileField只以优雅的方式接受特定类型的文件(视频、音频、pdf等)，服务器端?

9 个解决方案

#1

One very easy way is to use a custom validator.

一个非常简单的方法是使用自定义验证器。

In your app's validators.py:

在你的应用的validators.py:

def validate_file_extension(value):
    import os
    from django.core.exceptions import ValidationError
    ext = os.path.splitext(value.name)[1]  # [0] returns path+filename
    valid_extensions = ['.pdf', '.doc', '.docx', '.jpg', '.png', '.xlsx', '.xls']
    if not ext.lower() in valid_extensions:
        raise ValidationError(u'Unsupported file extension.')

Then in your models.py:

然后在你的models.py:

from .validators import validate_file_extension

... and use the validator for your form field:

…并在表单字段中使用验证器:

class Document(models.Model):
    file = models.FileField(upload_to="documents/%Y/%m/%d", validators=[validate_file_extension])

See also: How to limit file types on file uploads for ModelForms with FileFields?.

参见:如何限制带有文件字段的ModelForms在文件上传时的文件类型?

#2

Django in version 1.11 has a newly added FileExtensionValidator for model fields, the docs is here: https://docs.djangoproject.com/en/dev/ref/validators/#fileextensionvalidator.

Django在1.11版本中新增了一个用于模型字段的FileExtensionValidator，文档在这里:https://docs.djangoproject.com/en/dev/ref/validators/# FileExtensionValidator。

An example of how to validate a file extension:

如何验证文件扩展名的示例:

from django.core.validators import FileExtensionValidator
from django.db import models

class MyModel(models.Model):
    pdf_file = models.FileField(upload_to='foo/',
                                validators=[FileExtensionValidator(allowed_extensions=['pdf'])])

Note that this method is not safe. Citation from Django docs:

注意，此方法不安全。Django文档的引用:

Don’t rely on validation of the file extension to determine a file’s type. Files can be renamed to have any extension no matter what data they contain.

不要依赖对文件扩展名的验证来确定文件的类型。无论文件包含什么数据，都可以将其重命名为具有任何扩展名。

There is also new validate_image_file_extension (https://docs.djangoproject.com/en/dev/ref/validators/#validate-image-file-extension) for validating image extensions (using Pillow).

还有新的validate_image_file_extension (https://docs.djangoproject.com/en/dev/ref/validators/# validate-imag-file -extension)，用于验证图像扩展(使用Pillow)。

#3

There's a Django snippet that does this:

有一个Django代码片段可以做到这一点:

import os

from django import forms

class ExtFileField(forms.FileField):
    """
    Same as forms.FileField, but you can specify a file extension whitelist.

    >>> from django.core.files.uploadedfile import SimpleUploadedFile
    >>>
    >>> t = ExtFileField(ext_whitelist=(".pdf", ".txt"))
    >>>
    >>> t.clean(SimpleUploadedFile('filename.pdf', 'Some File Content'))
    >>> t.clean(SimpleUploadedFile('filename.txt', 'Some File Content'))
    >>>
    >>> t.clean(SimpleUploadedFile('filename.exe', 'Some File Content'))
    Traceback (most recent call last):
    ...
    ValidationError: [u'Not allowed filetype!']
    """
    def __init__(self, *args, **kwargs):
        ext_whitelist = kwargs.pop("ext_whitelist")
        self.ext_whitelist = [i.lower() for i in ext_whitelist]

        super(ExtFileField, self).__init__(*args, **kwargs)

    def clean(self, *args, **kwargs):
        data = super(ExtFileField, self).clean(*args, **kwargs)
        filename = data.name
        ext = os.path.splitext(filename)[1]
        ext = ext.lower()
        if ext not in self.ext_whitelist:
            raise forms.ValidationError("Not allowed filetype!")

#-------------------------------------------------------------------------

if __name__ == "__main__":
    import doctest, datetime
    doctest.testmod()

#4

First. Create a file named formatChecker.py inside the app where the you have the model that has the FileField that you want to accept a certain file type.

第一。创建一个名为formatChecker的文件。py在应用中，你有一个模型它有你想要接受的文件类型的FileField。

This is your formatChecker.py:

这是你formatChecker.py:

from django.db.models import FileField
from django.forms import forms
from django.template.defaultfilters import filesizeformat
from django.utils.translation import ugettext_lazy as _

class ContentTypeRestrictedFileField(FileField):
    """
    Same as FileField, but you can specify:
        * content_types - list containing allowed content_types. Example: ['application/pdf', 'image/jpeg']
        * max_upload_size - a number indicating the maximum file size allowed for upload.
            2.5MB - 2621440
            5MB - 5242880
            10MB - 10485760
            20MB - 20971520
            50MB - 5242880
            100MB 104857600
            250MB - 214958080
            500MB - 429916160
"""
def __init__(self, *args, **kwargs):
    self.content_types = kwargs.pop("content_types")
    self.max_upload_size = kwargs.pop("max_upload_size")

    super(ContentTypeRestrictedFileField, self).__init__(*args, **kwargs)

def clean(self, *args, **kwargs):        
    data = super(ContentTypeRestrictedFileField, self).clean(*args, **kwargs)

    file = data.file
    try:
        content_type = file.content_type
        if content_type in self.content_types:
            if file._size > self.max_upload_size:
                raise forms.ValidationError(_('Please keep filesize under %s. Current filesize %s') % (filesizeformat(self.max_upload_size), filesizeformat(file._size)))
        else:
            raise forms.ValidationError(_('Filetype not supported.'))
    except AttributeError:
        pass        

    return data

Second. In your models.py, add this:

第二。在你的模型。py,添加:

from formatChecker import ContentTypeRestrictedFileField

Then instead of using 'FileField', use this 'ContentTypeRestrictedFileField'.

然后使用“ContentTypeRestrictedFileField”而不是“FileField”。

Example:

例子:

class Stuff(models.Model):
    title = models.CharField(max_length=245)
    handout = ContentTypeRestrictedFileField(upload_to='uploads/', content_types=['video/x-msvideo', 'application/pdf', 'video/mp4', 'audio/mpeg', ],max_upload_size=5242880,blank=True, null=True)

Those are the things you have to when you want to only accept a certain file type in FileField.

当您只想在FileField中接受特定的文件类型时，您必须这样做。

#5

I think you would be best suited using the ExtFileField that Dominic Rodger specified in his answer and python-magic that Daniel Quinn mentioned is the best way to go. If someone is smart enough to change the extension at least you will catch them with the headers.

我认为你最适合使用多米尼克·罗杰在他的回答中提到的ExtFileField和丹尼尔·奎因提到的python-magic是最好的方法。如果有人足够聪明地更改了扩展名，至少您可以用header捕获他们。

#6

You can use the below to restrict filetypes in your Form

您可以使用下面的方法来限制表单中的文件类型。

file = forms.FileField(widget=forms.FileInput(attrs={'accept':'application/pdf'}))

#7

Additionally i Will extend this class with some extra behaviour.

另外，我将通过一些额外的行为来扩展这个类。

class ContentTypeRestrictedFileField(forms.FileField):
    ...
    widget = None
    ...
    def __init__(self, *args, **kwargs):
        ...
        self.widget = forms.ClearableFileInput(attrs={'accept':kwargs.pop('accept', None)})
        super(ContentTypeRestrictedFileField, self).__init__(*args, **kwargs)

When we create instance with param accept=".pdf,.txt", in popup with file structure as a default we will see files with passed extension.

当我们使用param accept=".pdf创建实例时。txt"，在弹出的默认文件结构中，我们将看到文件通过了扩展名。

#8

You can define a list of accepted mime types in settings and then define a validator which uses python-magic to detect the mime-type and raises ValidationError if the mime-type is not accepted. Set that validator on the file form field.

您可以在设置中定义一个已接受的mime类型列表，然后定义一个验证器，该验证器使用python-magic来检测mime类型，并在不接受mime类型时引发ValidationError。在文件表单字段上设置验证器。

The only problem is that sometimes the mime type is application/octet-stream, which could correspond to different file formats. Did someone of you overcome this issue?

唯一的问题是，有时mime类型是应用程序/octet-stream，它可以对应不同的文件格式。你们有人解决过这个问题吗?

#9

A few people have suggested using python-magic to validate that the file actually is of the type you are expecting to receive. This can be incorporated into the validator suggested in the accepted answer:

一些人建议使用python-magic来验证文件实际上是您期望收到的类型。这可以并入已接受的答案中所建议的验证器:

import os
import magic
from django.core.exceptions import ValidationError

def validate_is_pdf(file):
    valid_mime_types = ['application/pdf']
    file_mime_type = magic.from_buffer(file.read(1024), mime=True)
    if file_mime_type not in valid_mime_types:
        raise ValidationError('Unsupported file type.')
    valid_file_extensions = ['.pdf']
    ext = os.path.splitext(file.name)[1]
    if ext.lower() not in valid_file_extensions:
        raise ValidationError('Unacceptable file extension.')

This example only validates a pdf, but any number of mime-types and file extensions can be added to the arrays.

此示例仅验证pdf，但是可以向数组中添加任意数量的mime类型和文件扩展名。

Assuming you saved the above in validators.py you can incorporate this into your model like so:

假设您将上面的内容保存在验证器中。py，你可以把它合并到你的模型中，比如:

from myapp.validators import validate_is_pdf

class PdfFile(models.Model):
    file = models.FileField(upload_to='pdfs/', validators=(validate_is_pdf,))