Django rest framrwork Nested Serializer's fields not appearing in parent serializer

Question

In my Django app (using drf), I've modified my model's serializer to get the front-end's desired input, but I'm having zero luck trying to nest this serializer inside another one.

I've tried creating a field of the model with the to_representation method and putting a get_photos method, none of which amounted to anything.

# models.py

class Photo(models.Model):
    photo = models.OneToOneField(RawPhoto, related_name='contest_photo', on_delete=models.CASCADE)
    thumbnail_size = models.OneToOneField(PhotoSize, related_name='contest_photo', on_delete=models.CASCADE)
    thumbnail_url = models.TextField(verbose_name='thumbnail_url')

    class Meta:
        verbose_name = 'Contest Photo'

    @property
    def get_photo_src(self):
        return settings.MEDIA_URL + self.photo.image.name

    @property
    def get_thumbnail_url(self):
        # dont forget to add cache
        if len(self.thumbnail_url) == 0:
            file_name = self.get_photo_src
            last_dot = file_name.rfind('.')
            photo_name, photo_extension = file_name[:last_dot], file_name[last_dot:]
            self.thumbnail_url = photo_name + '_' + self.thumbnail_size.name + photo_extension

        return self.thumbnail_url

# serializers.py

class PhotoSerializer(serializers.ModelSerializer):
    thumbnail_height = serializers.ReadOnlyField(source='thumbnail_size.height')
    thumbnail_width = serializers.ReadOnlyField(source='thumbnail_size.width')
    src = serializers.ReadOnlyField(source='get_photo_src')
    thumbnail_url = serializers.ReadOnlyField(source='get_thumbnail_url')
    caption = serializers.ReadOnlyField(source='photo.caption')
    class Meta:
        model = Photo
        fields = ['src', 'thumbnail_url', 'thumbnail_height', 'thumbnail_width', 'caption']

class GallerySerializer(serializers.ModelSerializer):
    photos = PhotoSerializer(many=True)
    class Meta:
        model = Gallery
        fields = ['title', 'photos']

PhotoSerializer actually returns the full description of the object that I expect from it, but when I nest it inside GallerySerializer, it only shows thumbnail_url, which is the only field that is included in the model itself. Is there anyway I can include PhotoSerializer's fields inside GallerySerializer? (which is supposed to be a list of Photos)

Thanks.

Answer 1

use the depth argument as described here

class GallerySerializer(serializers.ModelSerializer):
    photos = PhotoSerializer(many=True)
    class Meta:
        depth=1
        model = Gallery
        fields = ['title', 'photos']