python - 从管理界面删除 ImageField 时出现 Django unicode 错误

Question

当使用“清除”复选框删除上传的图像并在 Django 管理界面中单击“保存”时，我得到以下结果:

TypeError at /admin/foo/bar/1/

coercing to Unicode: need string or buffer, ImageFieldFile found

Exception Value: coercing to Unicode: need string or buffer, ImageFieldFile found Exception Location: /home/ec2-user/ve/Project/lib/python2.6/site-packages/django/core/files/images.py in get_image_dimensions, line 47

我知道这可能与返回的 unicode 类型有关，因此在相关 中已从 return image 更改为 return image.name ImageField代码但这并没有解决问题。这是调试日志:

/home/user/ve/Project/lib/python2.6/site-packages/django/db/transaction.py
in inner
              return func(*args, **kwargs) ...

/home/user/ve/Project/lib/python2.6/site-packages/django/contrib/admin/options.py
in change_view
          if form.is_valid(): ...

/home/user/ve/Project/lib/python2.6/site-packages/django/forms/forms.py
in is_valid
      return self.is_bound and not bool(self.errors) ...

/home/user/ve/Project/lib/python2.6/site-packages/django/forms/forms.py
in _get_errors
          self.full_clean() ...

/home/user/ve/Project/lib/python2.6/site-packages/django/forms/forms.py
in full_clean
      self._clean_fields() ...

/home/user/ve/Project/lib/python2.6/site-packages/django/forms/forms.py
in _clean_fields
                  value = field.clean(value, initial) ...

/home/user/Devel/Project/project-cms/project/forms.py in clean
      w, h = get_image_dimensions(image) ...

/home/user/ve/Project/lib/python2.6/site-packages/django/core/files/images.py
in get_image_dimensions
      file = open(file_or_path, 'rb') ...

get_image_dimensions 方法的导入如下: 从 django.core.files.images 导入 get_image_dimensions

这是 clean 函数的主体:

def clean(self, value, initial=None):
    image = super(TheImageField, self).clean(value, initial)
    if image is None: return
    w, h = get_image_dimensions(image)
    if w != TheImageField.required_width or h != TheImageField.required_height:
        error_message = self.error_messages['incorrect_size'] % (w,h,)
        raise util.ValidationError(error_message)
    return image

Answer 1

The signature for function get_image_dimensions是这个吗:

def get_image_dimensions(file_or_path, close=False)

file_or_path 应该是磁盘中文件的字符串，而不是 ImageField，因此会出现错误。

你可以这样做:

def clean(self, value, initial=None):
    image = super(TheImageField, self).clean(value, initial)
    if image is None: return
    # this is where I changed the code to add image.path
    w, h = get_image_dimensions(image.path)
    if w != TheImageField.required_width or h != TheImageField.required_height:
        error_message = self.error_messages['incorrect_size'] % (w,h,)
        raise util.ValidationError(error_message)
    return image

希望这有帮助!