Django中的文件上传类型验证

Question

我正在尝试验证Django中的上传文件类型功能。允许的扩展将仅为xml。管理员将上传一个xml文件，然后用xml文件中的数据填充表。模型没有filefield，但是表单有。

accounts/models.py --

class Coupling(models.Model):
    coupling_name = models.CharField(max_length=150, blank=False, null=True, default="")
    module_name = models.TextField(blank=False, null=True)
    def __str__(self):
        return self.coupling_name

    class Meta:
        verbose_name_plural = "Couplings"

accounts/forms.py --

class CouplingUploadForm(forms.ModelForm):

    coupling_file = forms.FileField(label='XML File Upload:', required=True)

    class Meta:
        model = models.Coupling
        exclude = ['coupling_name', 'module_name']

settings.py

UPLOAD_PATH = os.path.join(BASE_DIR, "static", "uploads")

CONTENT_TYPES = ['xml']
MAX_UPLOAD_SIZE = "2621440"

accounts/admin.py

class couplingAdmin(admin.ModelAdmin):
    list_display = ('coupling_name','module_name')
    form = CouplingUploadForm
admin.site.register(Coupling, couplingAdmin)

我已经看过了一些SOF引用，其中大多数都有model.FileField，但在我的例子中，我不想将文件保存在模型中。

我试过使用魔术-- https://djangosnippets.org/snippets/3039/，但是我得到了一条python --魔术安装错误--无法找到lib魔术。所以我想不带魔法的去做。

任何帮助/建议/链接都将受到高度赞赏。提前谢谢。

Answer 1

您可以创建一个自定义validator。

def validate_file_extension(value):
    import os
    from django.core.exceptions import ValidationError
    ext = os.path.splitext(value.name)[1]
    valid_extensions = ['.xml']
    if not ext.lower() in valid_extensions:
        raise ValidationError(u'Unsupported file extension.')

然后在表单字段中

coupling_file = forms.FileField(label='XML File Upload:',
                               required=True, validators=[validate_file_extension])

Answer 2

只需将clean方法写入forms.py

import os 

def clean_coupling_file(self):
    file = self.cleaned_data['coupling_file']
    extension = os.path.splitext(file.name)[1]  # [0] returns path+filename
    VALID_EXTENSION = '.xml'

    if extension != VALID_EXTENSION:
        self.add_error(
            'coupling_file',
            _('Only files with ".xml" extension are supported, '
              'received: "%s" file.' % extension)
        )
    return file