python - 向字段添加自定义验证，用于通用 View CreateView

Question

问题

在Django 1.3 中为表单字段添加自定义验证，表单由通用 View CreateView 创建。

模型

class Picture(models.Model):
    file = models.ImageField(upload_to=get_image_path)
    filename = models.CharField(max_length=50, blank=True)
    user = models.ForeignKey(User, editable=False)
    upload_date = models.DateTimeField(auto_now_add=True,editable=False)

通用 View CreateView，稍作修改

class PictureCreateView(CreateView):
    model = Picture

    def clean_file(self,form):
        if image:
            if image._size > settings.MAX_IMAGE_SIZE:
                raise ValidationError("Image file too large ( > 20mb )")
        else:
             raise ValidationError("Couldn't read uploaded image")

    def get_form(self, form_class):
        form = super(PictureCreateView, self).get_form(form_class)
        form.instance.user = self.request.user
        return form

    def form_invalid(self, form):
        ...omitted none important code...
        response = JSONResponse(data, {}, response_mimetype(self.request))
        response['Content-Disposition'] = 'inline; filename=files.json'
        return response

    # Called when we're sure all fields in the form are valid
    def form_valid(self, form):
        ...omitted none important code...
        response = JSONResponse(data, {}, response_mimetype(self.request))
        response['Content-Disposition'] = 'inline; filename=files.json'
        return response

我的问题是:如何在到达 form_valid() 之前对文件字段进行自定义验证？

简而言之，到目前为止我做了什么

根据此处的文档 - https://docs.djangoproject.com/en/dev/ref/forms/validation/我应该能够覆盖文件字段表单验证器，我正在尝试使用 clean_file()“表单子(monad)类中的 clean_() 方法 - 其中替换为表单字段属性的名称。”如果我手动创建表单，这会很容易，但它是由 Django 通过通用 View 从模型创建的。

我目前的解决方案是一个丑陋的 hack:你可以看到我已经覆盖了 form_valid() 和 form_invalid()，在 form_valid() 我现在调用 clean_file()如果这是一个错误，我调用 form_invalid()。这会产生一些问题，例如我需要手动创建错误消息响应。

Answer 1

为什么不 create your modelform ？

from django import forms

class PictureForm(forms.ModelForm):
    def clean_file(self,form):
        if image:
            if image._size > settings.MAX_IMAGE_SIZE:
                raise ValidationError("Image file too large ( > 20mb )")
        else:
            raise ValidationError("Couldn't read uploaded image")

    class Meta:
        model = Picture

然后您可以在您的 View 中使用 the form_class attribute :

class PictureCreateView(CreateView):
    form_class = PictureForm

    # .... snip