message.py

#### users/models.py

class Message(models.Model):
  user = ForeignKeyField()
  # we could add a priorty or level field if we want, but lets not do that until we know we need it
  app_name = CharField(default='users') # i.e. 'impact'
  template = CharField(default='message.html') # i.e. 'badge_message.html'
  heading = CharField()
  content = TextField()
  action = HStoreField()
  image = HStoreField()
  link = HStoreField()

# Alternative Message Model
# Probably gives us better flexibility
class Message(models.Model):
  user = ForeignKeyField()
  app_name = CharField(default='users') # i.e. 'impact'
  template = CharField(default='message.html') # i.e. 'badge_message.html'
  heading = CharField()
  content = TextField()
  # replace the HStoreFields with a single context JSONField
  # https://docs.djangoproject.com/en/1.11/ref/contrib/postgres/fields/#jsonfield
  context = JSONField()
  """
  context = {
    'action': {
      'button-call': 'btn-paddle', 'button-data-id': 123
      }, 
    'image': {...}
  }
  
  Message.objects.create(..., context=context)
  """
  
  
#### users/messages.py
def notify(user, type, heading, content="", action=None, image=None, link=None):
  # create a record in the database and return the new model instance
  return Message.objects.create(...)

def get_unread_messages_by_user(user):
  return user.messages.filter(read=False)

#### impact/game.py
# import the messages module
from ..users import messages

# ...

def complete_action():
  ...
  # PLEASE WAIT for me to start to work on this function.
  # We'll pair code this piece since it will be great exercise in automated testing.
  # You can see tests here impact/tests/test_game.py
  """
  If the user is being awarded points
  - Check if there is already an unread message with type = "points"
  - If there is a record then update with a new message alerting the user of all unread points.
  - MAYBE we won't try to solve this problem right now.
  """
  messages.notify(...)


#### impact/views.py
from ..users import messages
class ImpactDetail(DetailView):
  def get_context_data():
    # ...
    context['users'] = messages.get_unread_messages_for_user(self.request.user)
    # ...
  

"""
The following two message templates are meant to illustrate the point 
that we can defer to individual apps to implement custom message templates.
For insance, the impact app can have its own message templates unique to 
game notifications.

The messages system expects a subfolder named "messages" to exist in the
app's template folder so there would be something like: 
"templates/impact/messages/*"
"""
  
#### templates/impact/messages/badge_message.html
<h2>{{ message.heading }}<h2>

<img src="{% static 'images/badges/' + message.image.filename %}" alt="{{ message.image.alt }}" />

<p>{{ message.content }}</p>


#### templates/users/messages/tour_message.html
<h2>{{ message.heading }}<h2>
<p>{{ message.content }}</p>

{% if message.action %}
<button id="begin-tour" data_id="{{ message.action.id }}" class="btn {{ message.action.button_class">{{ message.action.label }}</button>
{% endif %}


#### templates/users/messages/messages.html
{% for message in messages %}

  {% include message.app + '/messages/' + message.template with message=message %}
  
{% endfor %}