👀 Views: 92 💬 Answers: 1 📅 Created: 2025-06-09

django sqlalchemy signals Python

I'm working with an scenario where a Django signal doesn't seem to fire when I'm using SQLAlchemy's `bulk_save_objects` method to insert multiple records into the database. My setup involves Django 3.2 and SQLAlchemy 1.4, and I'm trying to create several instances of a model called `Item`. I've connected a post-save signal to the `Item` model that sends a notification whenever a new item is created. However, when I use `bulk_save_objects`, this signal is not triggered, and the notification is not sent. I've tried using the `session.commit()` after the bulk operation, but that doesn't seem to help. Here’s a simplified version of my code: ```python from sqlalchemy.orm import sessionmaker from myapp.models import Item from myapp.signals import item_created_signal # Create a new session database_session = sessionmaker(bind=engine)() items_to_create = [Item(name=f'Item {i}') for i in range(10)] # This is where I do the bulk save try: database_session.bulk_save_objects(items_to_create) database_session.commit() except Exception as e: database_session.rollback() print(f'An behavior occurred: {e}') ``` I expected the `item_created_signal` to be fired for each new `Item`, but I haven’t seen any output from the signal handler. I also checked the signal registration and it seems to be done correctly: ```python @receiver(post_save, sender=Item) def notify_item_created(sender, instance, created, **kwargs): if created: print(f'New item created: {instance.name}') ``` Is there something specific about using `bulk_save_objects` that prevents Django signals from firing? Should I consider an alternative approach for batch inserts in this scenario? Any insights would be greatly appreciated!