[FIXED] Django rest not getting the image and attribute fields for any of my parent and child product

Issue

I crate an product model where I am showing all children product under it's parent but I am not seeing image and arribute fileds for any of my product. here my code

**models.py
class Product(models.Model):
    parent_product = models.ForeignKey('self',on_delete=models.CASCADE,null=True, blank=True)
    ...others fileds   
     
    
class Attribute(models.Model):
    name = models.CharField(max_length=100)
    product = models.ForeignKey(Product, on_delete=models.CASCADE)
   
 
class ProductImage(models.Model):
    product = models.ForeignKey(Product, on_delete=models.CASCADE)
    image = models.ImageField(upload_to='product_images/')
     

serilizer.py

class AttributeSerializer(serializers.ModelSerializer):
    class Meta:
        model = Attribute
        fields = ('name',)

class ProductImageSerializer(serializers.ModelSerializer):
    
    class Meta:
        model = ProductImage
        fields = ('image',)

class ChildProductSerializer(serializers.ModelSerializer):
    attributes = AttributeSerializer(many=True, read_only=True)
    images = ProductImageSerializer(many=True, read_only=True)

    class Meta:
        model = Product
        fields = '__all__'

class ProductSerializer(serializers.ModelSerializer):
    children = serializers.SerializerMethodField()
    attributes = AttributeSerializer(many=True, read_only=True)
    images = ProductImageSerializer(many=True, read_only=True)

    class Meta:
        model = Product
        fields = '__all__'

    def get_children(self, obj):
        children = Product.objects.filter(parent_product=obj)
        serializer = ChildProductSerializer(children, many=True)
        return serializer.data

here my response look like this

[
    {
        "id": 1,
        "children": [
        {...my children product}]
        "title": "hello test sashjhas ahsbahs ahs ba sh as",
        "slug": "hello-test-sashjhas-ahsbahs-ahs-ba-sh-as",
        "description": "",
        "orginal_price": "200.00",
        "discount_price": "180.00",
        "discount": "10.00",
        "available": true,
        "quantity": 1,
        "unit": null,
        "is_published": false,
        "sku": "c2a4a7fa-afbd-484a-9cdf-ec03284ab2cc",
        "createdAT": "2023-12-29 19:50:13.637279+00:00",
        "updatedAt": "2023-12-29 19:52:53.172203+00:00",
        "parent_product": null
    }
]

I added AttributeSerializer and ProductImageSerializer in my ProductSerializer and ChildProductSerializer but not getting the attribute and images

Solution

The related_name of a ForeignKey field should match the name of the field in the serializer class. By default the related_name is <the name of the field>_set. So to fix this you should follow one of the solutions below:

Solution 1: Change the related_name of the ForeignKey field

Here's the fix for the models.py file according to this solution:

from django.db import models
class Product(models.Model):
    parent_product = models.ForeignKey('self',on_delete=models.CASCADE,null=True, blank=True)
    available = models.BooleanField()  
    
    
class Attribute(models.Model):
    name = models.CharField(max_length=100)
    product = models.ForeignKey(Product, on_delete=models.CASCADE, related_name='attributes')


class ProductImage(models.Model):
    product = models.ForeignKey(Product, on_delete=models.CASCADE,  related_name='images')
    image = models.ImageField(upload_to='product_images/')

Solution 2: Change the fields in the serializer class

Here's the fix for the serializer.py in case you pick the solution no. 2:

from .models import Product,ProductImage,Attribute
from rest_framework import serializers
class AttributeSerializer(serializers.ModelSerializer):
    class Meta:
        model = Attribute
        fields = ('name',)

class ProductImageSerializer(serializers.ModelSerializer):
    
    class Meta:
        model = ProductImage
        fields = ('image',)

class ChildProductSerializer(serializers.ModelSerializer):
    attribute_set = AttributeSerializer(many=True, read_only=True)
    image_set = ProductImageSerializer(many=True, read_only=True)

    class Meta:
        model = Product
        fields = '__all__'

class ProductSerializer(serializers.ModelSerializer):
    children = serializers.SerializerMethodField()
    attribute_set = AttributeSerializer(many=True, read_only=True)
    image_set = ProductImageSerializer(many=True, read_only=True)

    class Meta:
        model = Product
        fields = '__all__'

    def get_children(self, obj):
        children = Product.objects.filter(parent_product=obj)
        serializer = ChildProductSerializer(children, many=True)
        return serializer.data

Answered By - Ehsan88