Serializers in Foreign Key Django - django

Question

i need to get information from Reservation, ReservationDetails and Product, but just get Reservation and ReservationDetails
i have 3 models
class Reservation(models.Model):
id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
userReservation = models.ForeignKey(User, on_delete=models.CASCADE, default=1)
dateStart = models.DateTimeField(null=False, blank=False, default=datetime.now)
dateFinish = models.DateTimeField(null=False, blank=False, default=datetime.now)
date_Created = models.DateTimeField(auto_now_add=True)
date_Modified = models.DateTimeField(auto_now=True, db_index=True)
def __str__(self):
return str(self.id)
class DetailsReservation(models.Model):
Reservation = models.ForeignKey(Reservation, blank=False, on_delete=models.CASCADE, null=True, related_name='reservation_details')
product = models.ForeignKey(Product, blank=False, on_delete=models.CASCADE, null=True, related_name='products_reservation')
Quantity = models.IntegerField(null=False, blank=False, default=0)
userbyReserva = models.ForeignKey(User, editable=False, on_delete=models.CASCADE, default=1)
class Product(models.Model):
product_Description = models.CharField(max_length=255)
Quantity = models.IntegerField(null=False, blank=False, default=0)
Quantity_Max_Reservation = models.IntegerField(null=False, blank=False, default=0)
product_Comments = models.CharField(max_length=255)
size = models.CharField(max_length=10, null=True)
product_Status = models.BooleanField(default=True)
category = models.ForeignKey(Category, on_delete=models.CASCADE, null=True, related_name='products')
date_Created = models.DateTimeField(default=datetime.now, blank=True)
date_Modified = models.DateTimeField(default=datetime.now, blank=True)
And i tried to create serializers
class ReservationDetailsSerializers(serializers.ModelSerializer):
products = serializers.PrimaryKeyRelatedField(queryset=Product.objects.all(), required=False)
class Meta:
model= DetailsReservation
fields = ['Reservation', 'Quantity', 'userbyReserva', 'products']
class ReservationDetailsListSerializer(serializers.ModelSerializer):
reservation_details = ReservationDetailsSerializers(many=True)
class Meta:
model = Reservation
fields = ['id', 'userReservation', 'dateStart', 'dateFinish', 'reservation_details']
but the response does not show this field
[
{
"id": "6d87ba1c-61bc-41bd-80c8-31a51df8d32f",
"userReservation": 1,
"dateStart": "2018-09-16T17:19:34-05:00",
"dateFinish": "2018-09-16T17:19:35-05:00",
"reservation_details": [
{
"Reservation": "6d87ba1c-61bc-41bd-80c8-31a51df8d32f",
"Quantity": 1,
"userbyReserva": 1
>>"here should show this information product"
}
]
},
{
"id": "0ed26395-2579-4c40-9a63-460f5095ac51",
"userReservation": 2,
"dateStart": "2018-09-16T19:21:24-05:00",
"dateFinish": "2018-09-16T19:21:24-05:00",
"reservation_details": [
{
"Reservation": "0ed26395-2579-4c40-9a63-460f5095ac51",
"Quantity": 1,
"userbyReserva": 2
}
]
}
]
and it is my views.py
class getAllReservationDetails(generics.ListCreateAPIView):
queryset = Reservation.objects.prefetch_related('reservation_details')
print(queryset.query)
serializer_class = ReservationDetailsListSerializer
def get_object(self):
queryset = self.queryset()
obj = get_object_or_404(queryset)
return obj
I review this Link, but i don't know, why doesn't show the information product.
But, that is not working as I wanted.
What should I do?

Answer 1

Did you try creating a serializer for the Product model and use it on the ReservationDetailsSerializers?
class ProductSerializer(serializers.ModelSerializer):
class Meta:
model = Product
fields = '__all__'
class ReservationDetailsSerializers(serializers.ModelSerializer):
products = ProductSerializer(source='product', required=False)
class Meta:
model= DetailsReservation
fields = ['Reservation', 'Quantity', 'userbyReserva', 'products']
You can find more about this topic on Specifying nested serialization

Answer 2

The DetailsReservation model has not attribute products, but it has product. So remove the "s" from products or use source = 'product' in ReservationDetailsSerializers serializer
Method - 1 : removal of "s"
class ReservationDetailsSerializers(serializers.ModelSerializer):
product = serializers.PrimaryKeyRelatedField(queryset=Product.objects.all(), required=False)
class Meta:
model= DetailsReservation
fields = ['Reservation', 'Quantity', 'userbyReserva', 'product']
Method - 2 : speciying source argument
class ReservationDetailsSerializers(serializers.ModelSerializer):
products = serializers.PrimaryKeyRelatedField(queryset=Product.objects.all(),
required=False, source='product')
class Meta:
model = DetailsReservation
fields = ['Reservation', 'Quantity', 'userbyReserva', 'products']
UPDATE
I think you need nested serializer representation. If so, you've to define a seperate serializer (say ProductSerializer) and add it to ReservationDetailsSerializers instead of serializers.PrimaryKeyRelatedField()
#new serializer class
class ProductSerializer(serializers.ModelSerializer):
class Meta:
model = Product
fields = '__all__' # you can specify the fields here
Hence Method-1 become
class ReservationDetailsSerializers(serializers.ModelSerializer):
product = ProductSerializer(required=False)
class Meta:
model= DetailsReservation
fields = ['Reservation', 'Quantity', 'userbyReserva', 'product']
and the Method-2 become
class ReservationDetailsSerializers(serializers.ModelSerializer):
products = ProductSerializer(required=False, source='product')
class Meta:
model = DetailsReservation
fields = ['Reservation', 'Quantity', 'userbyReserva', 'products']