How to get the nested objects in DRF - django-rest-framework

Question

I have two models Role and User. User model has a foreign-key field associated with model Role.
Model Role
class Role(models.Model):
role_name = models.CharField(max_length=255, blank=False, unique=True)
def __str__(self):
return 'Role Object ({})'.format(self.id, self.role_name)
Model User
class User(AbstractBaseUser, PermissionsMixin):
first_name = models.CharField(max_length=255, blank=False)
last_name = models.CharField(max_length=255, blank=False)
email = models.EmailField(max_length=255, blank=False, unique= True)
phone_number = models.BigIntegerField(blank=False, unique= True)
password = models.TextField(blank=False)
company_name = models.CharField(max_length=255, null=True, unique=True)
is_active = models.BooleanField(default= False)
role = models.ForeignKey(Role, related_name='group_name', on_delete=models.CASCADE, blank=False)
business = models.ForeignKey(Businesses, on_delete=models.CASCADE, null=True)
objects = UserManager()
USERNAME_FIELD = 'email'
def __str__(self):
return 'User Object ({})'.format(self.id)
Using ModelSerializer and ListAPIView I want to get the list of all the users as shown below -
{
"first_name": "",
"last_name":"",
"email":"",
"phone_number":,
"is_active":"",
"role":{
"id":1,
"role_name": "Admin"
}
}
Also, I have created serializers -
class AdminSerializer(serializers.ModelSerializer):
role = RoleSerializer(read_only=True)
class Meta:
model = User
fields = ['id', 'first_name', 'last_name', 'email', 'phone_number', 'password', 'role', 'is_active' ]
read_only_field = ['role_name']
extra_kwargs = {
'password':{
'write_only':True
},
'is_active':{
'required':False
}
}
def create(self, validated_data):
return User.objects.create_user(**validated_data)
class RoleSerializer(serializers.ModelSerializer):
class Meta:
model = Role
field = ['id', 'role_name']
What exactly should I do to my serializer to achieve desire output. What exactly should I write in my ListAPIView() what a ListAPIVIew returns.
class UsersListAPIView(ListAPIView):
queryset = User.objects.all()
serializer_class = AdminSerializer
def list(self, request):
queryset = self.get_queryset().filter(role=request.query_params.get['id']).prefetch_related("group_name")
serializer = AdminSerializer(queryset, many=True)
return Response(serializer.data)
This returns an error -
TypeError: 'method' object is not subscriptable