Django: Postgres connection does not close

Question

I have a problem with my django application accumulating postgres connections over time. It seems that every 30 minutes a new connection is established and the old connections are not closed (see. Screen). Since the maximum connections are set to 100 after a while, all connections are blocked.

Does anyone know what causes this problem?

I discovered this after I included some celery tasks. Therefore, I am absolutely sure that this is due to celery.

So, I tried to close the connection manually after each task using the method after_return:

from django.db import connection

class DBTask(Task):
    abstract = True

    def after_return(self, *args, **kwargs):
        connection.close()

@task(name='example', base=DBTask)
def example_task(value):
    # do some stuff

But that doesn't help either. Perhaps I am completely wrong, and he is not at all connected with celery.

My database configuration:

DATABASES = {
    'default': {
        'ENGINE': 'django.contrib.gis.db.backends.postgis',
        'NAME': 'production', 
        'USER': 'production', 
        'HOST': 'some.host', 
        'CONN_MAX_AGE': 0,
    },
}

Installed packages:

• django 1.8.9
• pyscopg2 2.6.1
• 3.1.20
• django-celery 3.1.17

webfaction (, )

question, CONN_MAX_AGE: 0 .

:

connection.close() celery, .

2:

connection.close() , .

3:

, :

celery_tasks.py

@task(name='push_notifications', base=DBTask)
def push_notifications_task(user_id):
    user = CustomUser.objects.get(id=user_id)
    PusherAPI().push_notifications(user)
    connection.close()

models.py

class PusherAPI(object):

    def push_notifications(self, user):
        from .serializers import NotificationSerializer
        self.pusher.trigger(
            'user_%s' % user.slug,
            'notifications',
            NotificationSerializer(user).data
        )

serializers.py

class NotificationSerializer(object):

    def __init__(self, user=None):
        if user is None:
            self.user = get_current_user()
        else:
            self.user = user

    @property
    def data(self):
        # get notifications from db
        notifications = self.user.notifications.unread()
        # create the notification dict
        ...
        return note_dict

db- CustomUser.objects.get(id=user_id) notifications = self.user.notifications.unread()

Answer 1

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