What are some examples of using signals in Django ORM?

What are some examples of using signals in Django ORM?

Django ORM signals allow you to execute certain actions automatically when specific events occur in your models. For example, you can use the post_save signal to perform an action right after a model instance is saved.

Can you give me a specific code example?

Sure! Here's a simple example:

from django.db.models.signals import post_save
from django.dispatch import receiver
from .models import MyModel

@receiver(post_save, sender=MyModel)
def my_handler(sender, instance, created, **kwargs):
    if created:
        print('A new instance was created:', instance)

This code will print a message every time a new MyModel instance is created.

What other signals are available in Django?

Django provides several built-in signals, including pre_save, post_delete, m2m_changed, and pre_delete. Each serves different purposes for handling model events.

How can I connect signals to multiple models?

You can connect a single signal to multiple models by specifying multiple sender arguments in the @receiver decorator or by creating separate handlers for each model.