Storing images and thumbnails on s3 in django

Question

I\'m trying to get my images thumbnailed and stored on s3 using django-storages, boto, and sorl-thumbnail. I have it working, but it\'s very slow, even with small images. I don\

Answer 1

I'm not sure if you problem is the same as mine, but I found that accessing the width or height property of a normal Django ImageField would read the file from the storage backend, load it into PIL, and return the dimensions from there. This is especially costly with a remote backend like we're using, and we have very media-heavy pages.

https://code.djangoproject.com/ticket/8307 was opened to address this but the Django devs closed as wontfix because they want the width and height properties to always return the true values. So I just monkeypatch _get_image_dimensions() to use those fields, which does prevent a large number of the boto messages and improves my page-load times.

Below is my code modified from the patch attached to that ticket. I stuck this in a place which gets executed early, such as a models.py.

from django.core.files.images import ImageFile, get_image_dimensions
def _get_image_dimensions(self):
    from numbers import Number
    if not hasattr(self, '_dimensions_cache'):
        close = self.closed
        if self.field.width_field and self.field.height_field:
            width = getattr(self.instance, self.field.width_field)
            height = getattr(self.instance, self.field.height_field)
            #check if the fields have proper values
            if isinstance(width, Number) and isinstance(height, Number):
                self._dimensions_cache = (width, height)
            else:
                self.open()
                self._dimensions_cache = get_image_dimensions(self, close=close)
        else:
            self.open()
            self._dimensions_cache = get_image_dimensions(self, close=close)

    return self._dimensions_cache
ImageFile._get_image_dimensions = _get_image_dimensions