SOS Django Template comes with its own app called core, which adds further functionality to your application. In this section, we will review those.

In Laravel, the default behavior for migration is to add creation datetime and last update datetime to each model. Of course, you can opt out if you'd like. Django lacks this feature. You wouldn't like to have an unwanted column in your database. However, we can agree that creation datetime and last update datetime fields are widely used and we can add one or two lines of code each time we want them, or we can also define snippets in our editor, that's one of the options, too.

This is what TimestampModel and ExtendedTimestampModel does. Instead of manually adding these line or using snippets, you have a standard way to define them. These models are abstract models, which means you can create a model by extending these.

TimestampModel only adds one field named created_at, which is a DatetimeField with auto_now_add=True, meaning it automatically adds the datetime when a model instance is created.

from core.models import TimestampModel
class YourModel(TimestampModel):
    # other fields
# later in code
your_model_instance.created_at

ExtendedTimestampModel both adds created_at and a field named last_update, which is a DatetimeField with auto_now=True, meaning it automatically passes the datetime each time a model instance gets updated.

from core.models import ExtendedTimestampModel
class YourModel(ExtendedTimestampModel):
    # other fields
# later in code
your_model_instance.created_at
your_model_instance.last_update

There comes a time where you define your URLs in an app of yours with TODOs. Then you want to write views and attach them later on. In those times, you can use not_implemented_view with TODOs so that whenever that URL is hit, you get a NotImplementedError. In order to use that:

# urls.py
from core.views import not_implemented_view
url_patterns = [
    path("home", not_implemented_view, name="home"),  # TODO attach home view
    path("about", not_implemented_view, name="about"),  # TODO attach about view
]

So when you request /home, you will have a page with error message saying "This view has not been implemented yet.".