django - Django(音频)文件验证

Question

我正在尝试一个允许用户上传音频文件的网站。我已经阅读了所有可以动手使用的文档，但是找不到太多有关验证文件的信息。

这里共有newb(以前从未做过任何形式的文件验证)，并试图弄清楚这一点。有人可以牵着我的手告诉我我需要知道什么吗？

与往常一样，先谢谢您。

Answer 1

您需要先验证文件，然后再将其写入磁盘。当您上载文件时，表单将得到验证，然后上载的文件将被传递到处理程序/方法，该处理程序/方法用于实际写入服务器上的磁盘。因此，在这两个操作之间，您需要执行一些自定义验证，以确保它是有效的音频文件

你可以:

检查文件是否小于一定大小(好的做法)

，然后检查提交的文件是否具有特定的内容类型(即音频文件)

这几乎没有用，因为有人可以轻易地欺骗它

然后检查文件是否以某个扩展名(或多个扩展名)结尾

这也很没用

尝试读取文件，看看它是否实际上是音频

(我尚未测试此代码)

models.py

class UserSong(models.Model):
    title = models.CharField(max_length=100)
    audio_file = models.FileField()

forms.py

class UserSongForm(forms.ModelForm):
     # Add some custom validation to our file field
     def clean_audio_file(self):
         file = self.cleaned_data.get('audio_file',False):
         if file:
             if file._size > 4*1024*1024:
                   raise ValidationError("Audio file too large ( > 4mb )")
             if not file.content-type in ["audio/mpeg","audio/..."]:
                   raise ValidationError("Content-Type is not mpeg")
             if not os.path.splitext(file.name)[1] in [".mp3",".wav" ...]:
                   raise ValidationError("Doesn't have proper extension")
             # Here we need to now to read the file and see if it's actually 
             # a valid audio file. I don't know what the best library is to 
             # to do this
             if not some_lib.is_audio(file.content):
                   raise ValidationError("Not a valid audio file")
             return file
         else:
             raise ValidationError("Couldn't read uploaded file")

views.py
从utils导入handle_uploaded_file

def upload_file(request):
    if request.method == 'POST':
        form = UserSongForm(request.POST, request.FILES)
        if form.is_valid():
            # If we are here, the above file validation has completed
            # so we can now write the file to disk
            handle_uploaded_file(request.FILES['file'])
            return HttpResponseRedirect('/success/url/')
    else:
        form = UploadFileForm()
    return render_to_response('upload.html', {'form': form})

utils.py

# from django's docs
def handle_uploaded_file(f):
    ext = os.path.splitext(f.name)[1]
    destination = open('some/file/name%s'%(ext), 'wb+')
    for chunk in f.chunks():
        destination.write(chunk)
    destination.close()

https://docs.djangoproject.com/en/dev/topics/http/file-uploads/#file-uploads
https://docs.djangoproject.com/en/dev/ref/forms/fields/#filefield
https://docs.djangoproject.com/en/dev/ref/files/file/#django.core.files.File