Subclassing the Django ImageFileField

Question

I\'m interested in subclassing django\'s ImageFileField to allow access to the image IPTC metadata, something like:

>>> from myapp.models import SomeMod         


        

Answer 1

It's not clear from your question: have you tried something like this?

class ImageMetadataMixin(object):
    """Mixin can be added to any image file"""
    @property
    def iptc(self):
        """Or something like this"""

class ImageWithMetadataFieldFile(ImageMetadataMixin, ImageFieldFile):
    pass

class ImageWithMetadataField(ImageField):
    attr_class = ImageWithMetadataFieldFile

I think it's all what necessary. Why do you think you need to redefine descriptor_class?

Answer 2

UPDATE: I have figured this one out -- thanks in part to the answer @valya provided. An example of a successful implementation can be found in my fork of django-imagekit:

https://github.com/fish2000/django-imagekit/blob/icc-develop/imagekit/modelfields.py