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Here's my code:

# models.py
class MyModel(models.Model):
    user = models.ForeignKey(User, on_delete=models.CASCADE)
    name = models.CharField(max_length=10)
    ...

# views.py
def get_all_models(request):
    return JsonResponse({"models": list(MyModel.objects.all())})

# urls.py
path('/mypath', views.get_all_models, name='get_all_models'),

This code works just fine if I visit /mypath. However, when I run an automated test using Django's test client, I get this error:

*** TypeError: Object of type MyModel is not JSON serializable

this is my test: from django.test import TestCase, Client from blog.tests.factories.user import UserFactory from blog.tests.factories.post import PostFactory

class MyModelTest(TestCase):
    def setUp(self):
        self.user = UserFactory.create()
        self.post = MyModelFactory.create(user=self.user)
        self.client = Client()

    def test_get_all_models(self):
        response = self.client.get("/mypath")
        pass

I suspect it has something to do with my factories:

import factory
from .models import User, MyModel

class UserFactory(factory.django.DjangoModelFactory):
    class Meta:
        model = User

    username = factory.Faker('word')
    email = factory.Faker('email')

class MyModelFactory(factory.django.DjangoModelFactory):
    class Meta:
        model = MyModel

    user = factory.SubFactory(UserFactory)
    name = factory.Faker('name')

How can I make my factories serializable?

NOTE: This question is not a duplicate. The other questions linked have view handlers that return HttpResponse objects, instead of JsonResponse objects. This distinction is key to my problem, because the error I'm seeing is related to JSON serialization that is supposed to be addressed by the JsonResponse class.

Also, the other questions do not involve factories. Factories are another key component of what I'm trying to do, which is run integration tests against data generated by factories.

dopatraman
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  • Possible duplicate of [ is not JSON serializable](https://stackoverflow.com/questions/16790375/django-object-is-not-json-serializable) – Brown Bear Apr 24 '19 at 06:00
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    Not a duplicate. The person who asked that question was returning an HttpResponse, whereas I'm using a JsonResponse. Also that question does not involve factory boy. – dopatraman Apr 24 '19 at 07:55
  • Are you sure that when you go to `/mypath` in the browser works? Has data the development database? – grouchoboy Apr 24 '19 at 08:34
  • It does, and the factories are also working as expected – dopatraman Apr 24 '19 at 16:12
  • Does the MyModel class have additional attributes or methods? If so, please update question to include full content of the class. – pygeek Jul 06 '20 at 23:22

2 Answers2

1

The code you shared assumes JSONResponse will serialize an ORM object, but according to Django documentation, it won't:

https://docs.djangoproject.com/en/3.0/ref/request-response/#jsonresponse-objects

https://docs.djangoproject.com/en/3.0/topics/serialization/#djangojsonencoder

It will work if you serialize the Django ORM object before passing it to JSONResponse

Consider doing the following:

from django.core import serializers
data = serializers.serialize("json", MyModel.objects.all())

https://docs.djangoproject.com/en/3.0/topics/serialization/

django-rest-framework is a very popular lib used in scenarios like the one you shared https://docs.djangoproject.com/en/3.0/topics/serialization/#djangojsonencoder

Márcio Carôso
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0

what about this:

def get_all_models(request):
    return JsonResponse({"models": list(MyModel.objects.all().values())},safe=False)

the point is here:

MyModel.objects.all().values()
safe=False
alireza yazdandoost
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