django-database-routing

Provides Primary/Replica database router for Django. See https://docs.djangoproject.com/en/dev/topics/db/multi-db/#an-example for example implementation.

Configuration

1. Add router to settings.py

DATABASE_ROUTERS = ['database_routing.PrimaryReplicaRouter']

2. Configure 'default' and 'replica' connections in settings.DATABASES
3. If needed you can force specific connections for some apps or models:

PRIMARY_REPLICA_ROUTING = {
  'my_app.MyModel': {
    'read': 'custom_connection',
    'write': 'custom_connection
  }
}

Forcing reading from primary

When transaction isolation level or replication lag causing bugs in your project, you can force your code to read all the data from default (or primary) database.

from database_routing import force_primary_read
@force_primary_read
def do_some_reads_and_updates():
    # All Django ORM queries are going to 'default' database here.
    # ...