truck - 0.1.3

Truck is an event bus layer on top of django signals.

Truck signals and listeners are nothing but regular django signals and listeners, the difference is that truck imports listeners automatically from each app, but gives you a global switch to enable and disable them.

It's intended to use in a django project that has a lot of test coverage, so that you can avoid slow listeners to run within automated tests.

Installation + setup

user@machine:~$ [sudo] pip install truck

inside settings.py

When django imports the truck app it will trigger its import engine that will find listeners.py inside each one of your installed apps.

There is more information about how it works below, for now just install the truck app before your local apps.

INSTALLED_APPS = (
    # Things Django Does
    'django.contrib.sessions',
    'django.contrib.sites',
   # ... django builtin apps

   # Then truck:

   "truck",

   # Then your apps
)

Using truck

Truck conveys "convention over configuration", it will try to import a file named listeners.py inside each Django app declared in settings.INSTALLED_APPS

In action

Considering a programmer wants to have the post_save signal connected to the User model.

{your_django_app}/listeners.py

from truck import receiver

from django.contrib.auth.models import User
from django.db.models.signals import post_save

from your_django_app.models import Profile


@receiver(post_save)
def create_profile(sender, instance=None, **kwargs):
    if isinstance(instance, User):
        profile, created = Profile.objects.get_or_create(user=instance)

Configuring

In order to disable truck, the programmer must set settings.TESTING to True:

INSTALLED_APPS = (
   # ...
   "truck",
   "your_django_app",
)

TESTING = True

The ideal django project layout will have different settings in your project: at least one for regular environment and another for running your tests.

settings/production.py

TESTING = False

settings/testing.py

TESTING = True

License: LGPL3

This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.