It’s sometimes useful to pr-populate your database with hard-coded data when you’re first setting up an app. You can provide initial data with fixtures.
1. Create your empty migration:
python manage.py makemigrations --empty <yourapp> --name load_intial_data
2. Edit your migration file <yourapp>/migrations/0002_load_intial_data.py
2.1. Custom implementation, inspired by Django loaddata
import os
from pathlib import Path
from django.db import migrations
from django.core import serializers
current_path = Path().absolute()
fixture_filename = 'initial_data.json'
def load_fixture_user_agent(apps, scheme_editor):
fixture_file = os.path.join(current_path, '<yourapp>', 'fixtures', fixture_filename )
with open(fixture_file, 'rb') as fin:
objects = serializers.deserialize('json', fin, ignorenonexistent=True)
for obj in objects:
obj.save()
def unload_fixture_user_agent(apps, scheme_editor):
'Brutally deleting all entries for this model...'
MyModel= apps.get_model('youtapp', 'MyModel')
MyModel.objects.all().delete()
class Migration(migrations.Migration):
dependencies = [
('yourapp', '0001_initial'),
]
operations = [
migrations.RunPython(load_fixture, reverse_code=unload_fixture),
]
2.2. A simpler solution for load_fixture
Useful if you want to use a custom directory.
from django.core.management import call_command
fixture_dir = os.path.abspath(os.path.join(os.path.dirname(__file__), '../fixtures'))
fixture_filename = 'initial_data.json'
def load_fixture(apps, schema_editor):
fixture_file = os.path.join(fixture_dir, fixture_filename)
call_command('loaddata', fixture_file)
2.3. Simplest: calling loaddata with app_label will load fixtures from the <yourapp>‘s fixtures dir automatically
from django.core.management import call_command
fixture = 'initial_data'
def load_fixture(apps, schema_editor):
call_command('loaddata', fixture, app_label='yourapp')
3. Run it
python manage.py migrate <yourapp>