Usage¶
django-nomad-notifier
is not functional by itself. You must do your
homework to get it running. This app is meant to provide only the essential
parts for the sole purpose of exposing a model and a mixin. Those minimal code
helps you build notification models that will inherit the functionality
and will hold the information needed in order to send email notifications
(and show them on web as well).
What we do at Nomadblue, for instance, is adding a new app notifications
that will store the models, templates, and any other related files.
Creating notification models¶
You must do three things to successfully create a new type of notification:
- Subclass
models.Notification
to get the model fields and basic methods. - Use the
NotificationMixin
to get the basic methods. - Override some methods to provide the minimal functionality.
For this documentation we are going to create a simple welcome message
notification that will be attached to a Django User
model whenever a
new user is created (i.e. a user signs up). It will be a notification that
will be sent via email and also displayed on a web notifications list.
Subclassing models.Notification
¶
First of all, the code for the impatient:
class WelcomeNotification(Notification, OurNotificationMixin, NotificationMixin):
"""Welcomes the user after signup"""
# This is the model instance that the notification will reference to. In this
# particular case, it has to be the user model who just signed up.
obj = models.OneToOneField(settings.AUTH_USER_MODEL)
# Template for web notification list
web_noti_tmpl = 'notifications/includes/welcome_notification_list_item.html'
# Templates for email notification
email_subject_tmpl = 'notifications/email/welcome_noti_subject.txt'
email_plaintext_body_tmpl = 'notifications/email/welcome_noti_plaintext_body.txt'
email_html_body_tmpl = 'notifications/email/welcome_noti_html_body.html'
def get_obj_url(self):
"""
This method is used to specify URL to redirect user after
notification is been cleared (a.k.a 'mark as read')
"""
return self.obj.get_absolute_url()
As you can see, we must provide the template paths for the two notification
types (web and email), the get_obj_url
method (used in the
views.ClearNotificationView
) and, the most important, adding the
NotificationMixin
so our model inherits the methods defined there and
which will help us sending the email notification.
But wait! You surely have taken into account on another mixin we are using,
OurNotificationMixin
. This mixin, whose code we provide below, holds
some other mandatory methods we must implement if we want to send
notifications via email:
class OurNotificationMixin(object):
from_email = settings.DEFAULT_FROM_EMAIL
def get_email_headers(self):
# Replace 'Your name' with your real name or project name
return {
'From': 'Your name <%s>' % self.from_email,
}
def get_recipients_list(self):
# Here we include only the notification user email but
# in fact the recipient/s could be whichever.
return [self.user.email]
These two methods are conveniently stored in a mixin because tipically we end up creating many notification models with different templates but the same common functionality.
Finally, we need to create our web and email templates. The property names are rather self-descriptive, but here it is defined what must each template contain:
web_noti_tmpl
: template that renders the web notification snippet (each item on a notification list).email_subject_tmpl
: template that contains the email subject (e.g. “Thanks for signing up”)email_plaintext_body_tmpl
: template containing the plaintext version of your email.email_html_body_tmpl
: template containing the HTML version of your email.
Sending email notifications¶
OK, now what? As the example we are describing is a notification message a
brand new user receives after the registration process in our site, we want
firstly to send the email. So, we could for instance create a new instance of
our WelcomeNotification
from our signup view:
try:
user.welcomenotification # In case user is re-visiting the view by mistake
except WelcomeNotification.DoesNotExist:
WelcomeNotification.objects.create(user=user, obj=user)
Last step is to make the call to the
NotificationMixin.send_notification_email
method. We fancy using
the post_save
signal here:
def send_email_notification(sender, instance, created, **kwargs):
if created:
instance.send_notification_email()
post_save.connect(send_email_notification, sender=WelcomeNotification)
Displaying web notifications¶
What about showing a list of notifications in the user interface, where they
can review them and clear them (mark as read)? We can go straight using the urls
and views powered in the app. Include the calls in your root urls.py
:
url(r'^notifications/', include('notifier.urls')),
Assuming that you have already created your template (its path stored in
web_noti_tmpl
), if you visit http://localhost:8000/notifications/
you should see a list of notifications. Of course you can go ahead and
override the notifier/notifications_list.html
template.
Types of notifications¶
In our previous example we created a web and email notification, i.e.
a notification that is sent via email and displayed on you website. But perhaps
you want to send an email but not show the notification via web. No problem!
The Notification
object supports specification of types of notifications
with its noti_type
field. Adjusting the creation of the notification above,
we would end up with:
try:
user.welcomenotification # In case user is re-visiting the view by mistake
except WelcomeNotification.DoesNotExist:
WelcomeNotification.objects.create(user=user, obj=user, noti_type=WelcomeNotification.EMAIL_NOTI)