python 39 lines · 8 steps

Sending a welcome email with Django signals

A post_save signal fires a multipart activation email whenever a new user is created.

Explained by highlit
Django Intermediate signals email user-activation templates event-driven
1from django.conf import settings
2from django.contrib.auth import get_user_model
3from django.core.mail import EmailMultiAlternatives
4from django.db.models.signals import post_save
5from django.dispatch import receiver
6from django.template.loader import render_to_string
7from django.urls import reverse
8from django.utils.encoding import force_bytes
9from django.utils.http import urlsafe_base64_encode
10 
11User = get_user_model()
12 
13 
14@receiver(post_save, sender=User, dispatch_uid="send_welcome_email")
15def send_welcome_email(sender, instance, created, **kwargs):
16 if not created or not instance.email:
17 return
18 
19 uid = urlsafe_base64_encode(force_bytes(instance.pk))
20 activation_path = reverse("accounts:activate", kwargs={"uidb64": uid, "token": instance.activation_token})
21 context = {
22 "user": instance,
23 "activation_url": settings.SITE_URL + activation_path,
24 "support_email": settings.SUPPORT_EMAIL,
25 }
26 
27 subject = "Welcome to Acme \u2014 confirm your email"
28 text_body = render_to_string("emails/welcome.txt", context)
29 html_body = render_to_string("emails/welcome.html", context)
30 
31 message = EmailMultiAlternatives(
32 subject=subject,
33 body=text_body,
34 from_email=settings.DEFAULT_FROM_EMAIL,
35 to=[instance.email],
36 reply_to=[settings.SUPPORT_EMAIL],
37 )
38 message.attach_alternative(html_body, "text/html")
39 message.send(fail_silently=False)
01 / 01
STEP 01

Walkthrough

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Three takeaways
  1. 1Django signals let you hook side effects onto model lifecycle events without touching the save logic.
  2. 2Guarding on the created flag ensures the handler runs once on creation, not on every update.
  3. 3EmailMultiAlternatives sends both plain-text and HTML bodies so clients render whichever they support.

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