django select related not giving expected result - django

Question

I am querying select related between two models Requirements and Badge Requirement has a related badge indicated by badge_id Models are,
class Badge(models.Model):
level = models.PositiveIntegerField(blank=False, unique=True)
name = models.CharField(max_length=255, blank=False , unique=True)
description = models.TextField(blank=True)
class Meta:
verbose_name = _("Badge")
verbose_name_plural = _("Badges")
def __str__(self):
return self.name
def get_absolute_url(self):
return reverse("Badge_detail", kwargs={"pk": self.pk})
""" Requirement Model for requirements """
class Requirement(models.Model):
number = models.PositiveIntegerField(blank=False)
badge = models.ForeignKey(Badge, on_delete=models.CASCADE)
name = models.CharField(max_length=255)
description = models.TextField(blank=True)
class Meta:
verbose_name = _("Requirement")
verbose_name_plural = _("Requirements")
def __str__(self):
return self.name
def get_absolute_url(self):
return reverse("Requirement_detail", kwargs={"pk": self.pk})
In My view I try to join both tables and retrieve. It is,
""" ajax requirements in requirements table """
def get_requirements(request):
requirements = Requirement.objects.all().select_related('badge').values()
print(requirements)
return JsonResponse(list(requirements), safe=False)
The result is,
to the frontend,
to the backend,
Why does it not give me both tables' values?

Answer 1

Best way to achieve that is using Serializers which are the key component to deal with transforming data from models to JSON and the inverse:
To use this approach you can create the following serializers:
yourapp.serializers.py
from rest_framework.serializers import ModelSerializer
from yourapp.models import Requirement, Badge
class BadgeSerializer(ModelSerializer):
class Meta:
model = Badge
fields = '__all__'
class RequirementSerializer(ModelSerializer):
badge = BadgeSerializer()
class Meta:
model = Requirement
fields = '__all__'
After that you should go to your views.py file and do the following changes:
from yourapp.serializers import RequirementSerializer
def get_requirements(request):
reqs = Requirement.objects.select_related('badge')
return JsonResponse(RequirementSerializer(reqs, many=True), safe=False)
In this way you will have a more flexible way to add or remove fields from the serializer, and your application is also going to be more decoupled and easy to maintain.