DRF get only the first serialized instance for list view?

Question

I'm working on a real estate app and want the listings to show only the first image of the Listing. Currently it is showing all images.

class Image(models.Model):
    photo = models.ImageField(blank=True, upload_to=get_image_filename)
    listing = models.ForeignKey(Listing, on_delete=models.CASCADE)


class ImageSerializerForListingList(serializers.ModelSerializer):
    photo = serializers.ImageField()

    class Meta:
        model = Image
        fields = ('photo', )


class ListingListSerializer(serializers.HyperlinkedModelSerializer):
    image = ImageSerializerForListingList(many=True, required=False, source='image_set')

    class Meta:
        model = Listing
        fields = ('url', 'address', 'image', )

    def get_first_image(self, obj):
        image = obj.image_set.all().first()
        return ImageSerializerForListingList(image, many=True).data

This is still showing all images,

Any advice on this?

Just use filter in your view and serialize only one object. Show me your model and view and I'll try to write solution. — Lothric, Mar 12 '20 at 01:08

score 0 · Answer 1 · answered Mar 12 '20 at 14:41

solution

"Although you define the get_first_image method on the ListingListSerializer, you are not using it anywhere.

The methods defined on the serializers only get used implicitly when there is a corresponding SerializerMethodField defined on the serializer."

class ListingListSerializer(serializers.HyperlinkedModelSerializer):
    first_image = serializers.SerializerMethodField()

    class Meta:
        model = Listing
        fields = ('url', 'address', 'first_image', )

    """Much like our web app our listing view should only show one Image"""

    def get_first_image(self, obj):
        image = obj.image_set.first()
        return FirstImageSerializer(image).data

Where did you define the FirstImageSerializer() ? – Fahd Nov 06 '22 at 08:37 — Fahd, Nov 06 '22 at 08:37

DRF get only the first serialized instance for list view?

1 Answers1

solution