Sometimes, I need to debug specific high-level tests by inspecting what gets created in the database as a side effect. I could use a debugger and poke around the Django ORM at a breakpoint - but quite often it’s simply faster to dump the entire table to JSON, see what’s there, and then apply fixes accordingly.

Normally, to do that, manage.py dumpdata could be used. But since tests are ephemeral and don’t necessarily preserve the database after they finish, a more scripted approach is often more convenient. This is where serializers.serialize comes in handy.

Here’s how to use it:

from django.core import serializers
from .models import Service

with open("dump.json", "w") as out:
    data = serializers.serialize("json", Service.objects.all())
    out.write(data)

and the result for my model is as shown below (auto-formatted for readability).

[
    {
        "model": "blog.service",
        "pk": 1,
        "fields": {
            "name": "SERVICE_1",
            "service_type": "L3Connection",
            "created_at": "2026-01-25T11:17:48.880Z"
        }
    },
    {
        "model": "blog.service",
        "pk": 2,
        "fields": {
            "name": "SERVICE_2",
            "service_type": "L3Connection",
            "created_at": "2026-01-25T11:17:48.880Z"
        }
    }
]

This approach is neat because it doesn’t prevent me from narrowing down the data. If I’m only interested in a subset of records, I can simply replace all() with filter() and dump exactly what I need.

To try it yourself inside a TestCase, feel free to copy-paste the snippet below:

class DebugWithDumpTests(TestCase):
    def test_dump_to_json(self) -> None:
        _ = Service.objects.create(service_type="L3Connection", name="SERVICE_1")
        _ = Service.objects.create(service_type="L3Connection", name="SERVICE_2")

        with open("dump.json", "w") as out:
            data = serializers.serialize("json", Service.objects.all())
            out.write(data)

but remember not to commit the database dump to your repository!

That’s it for today. Happy hacking! 🐍