Django built-in signals problem: error when using post_save
I'm building an app that notifies user when new ThreadedComments appear. For this I'm using post_save
signal. Here's my models.py
:
from django.db import models
from dja开发者_如何学Pythonngo.contrib.auth.models import User
from django.contrib.contenttypes.models import ContentType
from django.contrib.contenttypes import generic
from datetime import datetime
from threadedcomments.models import ThreadedComment
from django.db.models.signals import post_save
from blog.models import Post
from topics.models import Topic
class BuzzEvent(models.Model):
user = models.ForeignKey(User)
time = models.DateTimeField(default=datetime.now)
content_type = models.ForeignKey(ContentType)
object_id = models.PositiveIntegerField()
content_object = generic.GenericForeignKey()
def __unicode__(self):
return self.content_object
def buzz_on_comment(sender, **kwargs):
# This is called when there is a new ThreadedComment
comment = kwargs['instance']
user_attr_names = {
'post' : 'author',
'topic' : 'creator',
'tribe' : 'creator',
}
user = getattr(comment.content_object,
user_attr_names[comment.content_type.model])
BuzzEvent.objects.create(content_object=sender,
user=user,
time=datetime.now())
post_save.connect(buzz_on_comment, sender=ThreadedComment)
The problem is when a new ThreadedComment is created, I get an error: unbound method _get_pk_val() must be called with ThreadedComment instance as first argument (got nothing instead)
. Traceback and debugger says it happens when creating BuzzEvent object calls signals.pre_init.send
. I'm unable to hack django code right now, is there any obvious solution or idea?
Looks like it should be model instance (which comment
is) instead of model class (which sender
is) as the content_object argument:
BuzzEvent.objects.create(content_object=comment,
user=user)
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