pre_save & post_save model signals should also specify database to save

[Mandx]

The pre_save & post_save model signals should also specify on which database the object will be saved. Also, should be possible to connect to model signals on a specific database.

Something like:

from django.db.models.signals import pre_save
from myapp.models import MyModel

def my_default_handler(sender, **kwargs):
    # Do something on default db
    ...

def my_alternate_handler(sender, **kwargs):
    # Do something on alternate db
    ...

pre_save.connect(my_default_handler, sender=MyModel, database='default_db')
pre_save.connect(my_alternate_handler, sender=MyModel, database='alternate_db')

[Alex Gaynor]

Weeell, we can't add a param to the connect method, since Signal's don't know about models, or databases, or anything like that. However, the DB should be a param to the actual signal invocation so one can filter out the calls they want.

[Andrew Godwin]

Patch that adds "using" keyword for *_save, *_delete, m2m_changed

[Andrew Godwin]

I've attached a patch that implements a "using" keyword for pre_save, post_save, pre_delete, post_delete, and m2m_changed, along with modified docs and tests.

[Andrew Godwin]

Second patch, with removal of slash and

[Andrew Godwin]

Also include an AUTHORS commit.

[Russell Keith-Magee]

(In [13538]) Fixed #13552 -- Added a 'using' parameter to database signals. Thanks to gmandx for the suggestion, and Andrew Godwin for the patch.