Django signals for new entry only

Question

I'm using Django's post_save signal to send emails to users whenever a new article is added to the site. However, users still receive new emails whenever I use save() method for already created articles. How is it possible to receive emails only when NEW entry was added?

Thanks in advance

score 34 · Accepted Answer · answered Jun 18 '12 at 09:24

34

The post_save signal receives a boolean created argument which indicates if the saved instance was created.

def my_callback(sender, **kwargs):
    if kwargs['created']:
        print('Instance is new')

answered Jun 18 '12 at 09:24

Rob Cowie

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score 3 · Answer 2 · answered Jun 18 '12 at 09:24

3

Take a look at https://docs.djangoproject.com/en/dev/ref/signals/#django.db.models.signals.post_save

There actually is an argument passed with the signal "created: A boolean; True if a new record was created".

I think, that should do the trick.

answered Jun 18 '12 at 09:24

Christoph Eberhardt

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score 0 · Answer 3 · answered Jun 18 '12 at 09:04

0

Checking for instance.id is a nice way of determining if the instance is "new". This only works if you use ids that are auto-generated by your database.

answered Jun 18 '12 at 09:04

Iain Shelvington

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Won't work on a post_save signal IIRC - by that time the instance already have an id. – bruno desthuilliers Jun 18 '12 at 11:16

Django signals for new entry only

3 Answers3