def get_image_digests(self, image):
        """Get platform digests of specified image

        :param ImageName image: image
        :raises KeyError: when image is not found
        :rtype: dict
        :return: mapping platform:digest of the specified image
        """
        image_name_tag = self._key(image)
        image_digests = self._images_digests.get(image_name_tag)
        if image_digests is None:
            raise KeyError('Image {} has no digest records'.format(image_name_tag))
        return image_digests