Custom image models

The Image model can be customised, allowing additional fields to be added to images.

To do this, you need to add two models to your project:

• The image model itself that inherits from wagtail.images.models.AbstractImage. This is where you would add your additional fields
• The renditions model that inherits from wagtail.images.models.AbstractRendition. This is used to store renditions for the new model.

Here’s an example:

# models.py
from django.db import models

from wagtail.images.models import Image, AbstractImage, AbstractRendition


class CustomImage(AbstractImage):
    # Add any extra fields to image here

    # To add a caption field:
    # caption = models.CharField(max_length=255, blank=True)

    admin_form_fields = Image.admin_form_fields + (
        # Then add the field names here to make them appear in the form:
        # 'caption',
    )


class CustomRendition(AbstractRendition):
    image = models.ForeignKey(CustomImage, on_delete=models.CASCADE, related_name='renditions')

    class Meta:
        unique_together = (
            ('image', 'filter_spec', 'focal_point_key'),
        )

Then set the WAGTAILIMAGES_IMAGE_MODEL setting to point to it:

WAGTAILIMAGES_IMAGE_MODEL = 'images.CustomImage'

Migrating from the builtin image model

When changing an existing site to use a custom image model, no images will be copied to the new model automatically. Copying old images to the new model would need to be done manually with a data migration.

Any templates that reference the builtin image model will still continue to work as before but would need to be updated in order to see any new images.

Referring to the image model