Django: how can I tell if the post_save signal triggers on a new object?

django django-signals
Jon Tirsen picture Jon Tirsen · May 20, 2012 · Viewed 27.1k times · Source

I need to do some background post-processing on newly created objects in Django. This post-processing should only run on new objects, not objects that are just updated.

I know that in pre_save I can check if the object has an id, if it has not then it's a new object. But the problem is that in the post-processing I need access to the id (so that I can save the results back to the database).

How can I do this in a clean way?

Answer

seler picture seler · May 20, 2012

Have a look at docs: https://docs.djangoproject.com/en/stable/ref/signals/#post-save

There is a created named argument which will be set to True if it's a new object.

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