django.dispatch Signal Example Code

The Signal class allows certain senders to notify a set of receivers that some action has taken place across Django apps within the same project.

Example 1 from django-simple-history

django-simple-history is a code library that stores Django model state to track history, view and revert changes via the Django admin site. It is open source under the BSD 3-Clause "New" or "Revise" License.

django-simple-history / simple_history /

import django.dispatch

pre_create_historical_record = django.dispatch.Signal(
post_create_historical_record = django.dispatch.Signal(

Example 2 from aldryn-accounts

aldryn-accounts is a code library for user registration and authentication in Django projects. The code for this project is open source under the MIT license.

aldryn-accounts / aldryn_accounts /

# -*- coding: utf-8 -*-
import django.dispatch
from django.contrib.auth import user_logged_in
from django.db.models import signals, ObjectDoesNotExist
from django.utils.encoding import force_text
from django.utils import timezone
from django.contrib.auth.models import User

from .utils import generate_username

user_signed_up = django.dispatch.Signal(providing_args=["user", "form"])
user_sign_up_attempt = django.dispatch.Signal(providing_args=["username",  "email", "result"])
signup_code_sent = django.dispatch.Signal(providing_args=["signup_code"])
signup_code_used = django.dispatch.Signal(providing_args=["signup_code_result"])
email_confirmed = django.dispatch.Signal(providing_args=["email_address"])
email_confirmation_sent = django.dispatch.Signal(providing_args=["confirmation"])
password_changed = django.dispatch.Signal(providing_args=["user"])

# code continues from here without any further django.dispatch.Signal references

Example 3 from django-easy-timezones

django-easy-timezones (project website) is a Django middleware code library to simplify handling time data in your applications using users' geolocation data.

django-easy-timezones / easy_timezones /

# Django
import django.dispatch

detected_timezone = django.dispatch.Signal(providing_args=["instance", "timezone"])

Example 4 from viewflow

viewflow (project website) is a reusable workflow code library for organizing business logic in a complex web application. The code for the project is available under the GNU Alfredo license.

viewflow / viewflow /

from django.dispatch import Signal

flow_started = Signal(providing_args=["process", "task"])
flow_finished = Signal(providing_args=["process", "task"])

task_started = Signal(providing_args=["process", "task"])
task_failed = Signal(providing_args=["process", "task", "exception", 
task_finished = Signal(providing_args=["process", "task"])

Example 5 from django-registration (redux)

django-registration (redux) (project documentation) is a Django code library for one-phase, two-phase and three-phase registration flows. The code is available open source.

django-registration / registrations /

from django.conf import settings
from django.contrib.auth import get_backends
from django.contrib.auth import login
from django.dispatch import Signal

# An admin has approved a user's account
user_approved = Signal(providing_args=["user", "request"])

# A new user has registered.
user_registered = Signal(providing_args=["user", "request"])

# A user has activated his or her account.
user_activated = Signal(providing_args=["user", "request"])

def login_user(sender, user, request, **kwargs):
    """ Automatically authenticate the user when activated  """
    backend = get_backends()[0]  # Hack to bypass `authenticate()`.
    user.backend = "%s.%s" % (backend.__module__, backend.__class__.__name__)
    login(request, user)
    request.session['REGISTRATION_AUTO_LOGIN'] = True
    request.session.modified = True

if getattr(settings, 'REGISTRATION_AUTO_LOGIN', False):

Example 6 from django-cors-headers

django-cors-headers is an open source library for enabling Cross-Origin Resource Sharing (CORS) handling in your Django web applications and appropriately dealing with HTTP headers for CORS requests.

django-cors-headers / corsheaders /

from django.dispatch import Signal

# If any attached handler returns Truthy, CORS will be allowed for the request.
# This can be used to build custom logic into the request handling when the
# configuration doesn't work.
check_request_enabled = Signal(providing_args=["request"])
TwilioQuest logo.

Learn more Python in the awesome free TwilioQuest 16-bit adventure game.

1. Introduction 2. Development Environments 3. Data 4. Web Development 5. Deployment 6. DevOps Changelog What Full Stack Means About the Author Future Directions Page Statuses Django Code Examples django.urls.path django.conf.urls.url django.contrib.admin django.db.models Model django.dispatch Signal django.db.models.signal django.core.mail.send_mail django.core.mail.messages EmailMessage django.conf settings django.forms django.contrib.admin.sites register BaseCommand django.utils.timezone django.contrib.auth get_user_model django.contrib.auth.decorators login_required django.core.exceptions ImproperlyConfigured django.utils.html format_html django.contrib.auth.hashers make_password django.http Http404 django.http HttpResponse django.http HttpResponseForbidden django.http HttpResponseBadRequest django.contrib.admin.filters SimpleListFilter django.urls.exceptions NoReverseMatch django.http HttpResponsePermanentRedirect django.http HttpResponseNotModified django.http HttpResponseRedirect django.apps.config AppConfig django.db OperationalError django.forms CharField flask_sqlalchemy.SQLAlchemy Model django.db.models CharField django.db.models TextField django.db.models BooleanField flask request flask redirect django.db.models DateTimeField django.db.models IntegerField django.db.models AutoField django.db.models DateField django.db.models FileField django.db.models SlugField django.template.response TemplateResponse django.template.response SimpleTemplateResponse SQLAlchemy Model Examples django.urls reverse_lazy Flask Core and Extensions Code Examples ...or view the full table of contents.

Full Stack Python

Full Stack Python is an open book that explains concepts in plain language and provides helpful resources for those topics.
Updates via Twitter & Facebook.

Matt Makai 2012-2019