I don't understand this Django documentation. How do I use it this module?

I'm using the django_notification module. https://github.com/pinax/django-notification/blob/master/docs/usage.txt

This is what I do in my code to send an email to a user when something happens:

notification.send([to_user], "comment_received", noti_dict)

But, this seems to block the request. And it takes a long time to send it out. I read the docs and it says that it's possible to add it to a queue (asynchronous). How do I add it to an asynchronous queue?

I don't understand what the docs are trying to say. What is "emit_notices"? When do I call that? Do I have a script that calls that every 5 seconds? That's silly. What's the right way to do it asynchronously? What do I do?

Lets first break down what each does.

``send_now``
~~~~~~~~~~~~

This is a blocking call that will check each user for elgibility of the
notice and actually peform the send.

``queue``
~~~~~~~~~

This is a non-blocking call that will queue the call to ``send_now`` to
be executed at a later time. To later execute the call you need to use
the ``emit_notices`` man开发者_C百科agement command.

``send``
~~~~~~~~

A proxy around ``send_now`` and ``queue``. It gets its behavior from a global
setting named ``NOTIFICATION_QUEUE_ALL``. By default it is ``False``. This
setting is meant to help control whether you want to queue any call to
``send``.

``send`` also accepts ``now`` and ``queue`` keyword arguments. By default
each option is set to ``False`` to honor the global setting which is ``False``.
This enables you to override on a per call basis whether it should call
``send_now`` or ``queue``.

It looks like in your settings file you need to set

NOTIFICATION_QUEUE_ALL=True

And then you need to setup a cronjob (maybe every 10-30 seconds or something) to run something like,

django_admin.py emit_notices

This will periodically run and do the blocking call which sends out all the emails and whatever legwork the notification app needs. I'm sure if there is nothing to do it's not that intense of a workload.

And before you expand on your comment about this being silly you should think about it. It's not really silly at all. You don't want a blocking call to be tied to a web request otherwise the user will never get a response back from the server. Sending email is blocking in this sense.

Now, if you were just going to have the person receive this notification when they login, then you probably don't need to go this way because you do have to make an external call to sendmail or whatever you're using to send emails. But in your case, sending emails, you should do it this way.

According to those docs, send is just wrapping send_now and queue. So if you want to send the notifications asynchronous instead of synchronous you have 2 options:

1. Change your settings:

   # This flag will make all messages default to async
   NOTIFICATION_QUEUE_ALL = True
   

2. Use teh queue keyword argument:

   notification.send([to_user], "comment_received", noti_dict, queue=True)
   

If you queue the notifications you will have to run the emit_notices management command periodically. So you could put that in a cron job to run every couple of minutes.