How to output the value of the foreign key without using Django Rest Framework

Question

I have a problem with the Json values that are released by the Django. After I serialize my object from the views.py the user outputs a the id of the primary key not the value of the primary key. I tried the Natural keys technique in models.py. How can I get the value output instead of id?

views.py

def load_post(request):
    serials = serialize('json', Post.objects.all().order_by(
        "-id"))
    return JsonResponse(serials, safe=False)

models.py

from django.contrib.auth.models import AbstractUser
from django.db import models

#Natural Key technique 
class UserManager(models.Manager):
    def get_by_natural_key(self, username):
        return self.get(username=username)


class User(AbstractUser):
    objects = UserManager()


class Post(models.Model):
    id = models.AutoField(primary_key=True)
    user = models.ForeignKey(
        'User', on_delete=models.CASCADE, related_name='user')
    post = models.TextField(max_length=280, blank=True)
    timestamp = models.DateTimeField(auto_now_add=True)
    likes = models.IntegerField(default=0)

    def __str__(self):
        return f"id: {self.id}, username: {self.user}, post: {self.post}, datetime: {self.timestamp}, likes: {self.likes}"

Json output

[
   {
      "model":"network.post",
      "pk":3,
      "fields":{
         "user":1, #This should be a username
         "post":"afefawfawefawf",
         "timestamp":"2020-08-07T14:38:54.444Z",
         "likes":0
      }
   },
   {
      "model":"network.post",
      "pk":2,
      "fields":{
         "user":1, #This should be a username
         "post":"afefawfawefawf",
         "timestamp":"2020-08-07T14:38:18.687Z",
         "likes":0
      }
   },
   {
      "model":"network.post",
      "pk":1,
      "fields":{
         "user":2, #This should be a username
         "post":"sfoawefoawemfowf",
         "timestamp":"2020-08-07T14:28:09.784Z",
         "likes":0
      }
   }
]

Answer 1

If you want the natural key to be output by the built-in Django serializer, you need two additional things:

• Implement the natural_key() method on the User model
• Add use_natural_foreign_keys=True to the call to serialize()

The process is described in the Django documentation here: https://docs.djangoproject.com/en/3.1/topics/serialization/#serialization-of-natural-keys

In your case:

models.py

...

class User(AbstractUser):
    objects = UserManager()
    
    def natural_key(self):
        return self.username

...

views.py

def load_post(request):
    serials = serialize('json', Post.objects.all().order_by("-id"), use_natural_foreign_keys=True)
    return JsonResponse(serials, safe=False)

The get_by_natural_key() method is not used in serialization, but is needed to deserialize data with natural keys in it.