Merge pull request compserv#223 from alexander-zw/waitlist-email

Email notification for getting off the waitlist
ochan1 · Apr 28, 2020 · 2c5f039 · 2c5f039
2 parents aff1b43 + 0356cef
commit 2c5f039
Show file tree

Hide file tree

Showing 3 changed files with 65 additions and 4 deletions.
diff --git a/hknweb/events/models.py b/hknweb/events/models.py
@@ -50,6 +50,11 @@ def waitlist_set(self):
  return self.rsvp_set.none()
  return self.rsvp_set.order_by("created_at")[self.rsvp_limit:]
 
+ def newly_off_waitlist_rsvps(self, old_admitted):
+ """ old_admitted must be a set, not a QuerySet. QuerySets are mutable views into the database. """
+ new_admitted = set(self.admitted_set())
+ return new_admitted - old_admitted
+
 
 class Rsvp(models.Model):
  user = models.ForeignKey(User, models.CASCADE, verbose_name="rsvp'd by")
@@ -62,7 +67,7 @@ class Rsvp(models.Model):
  # updated_at = models.DateTimeField(auto_now=True)
 
  def __repr__(self):
- return "Rsvp(event={})".format(self.event)
+ return "Rsvp(event={}, user={})".format(self.event, self.user.username)
 
  def __str__(self):
  return self.event.name

diff --git a/hknweb/events/templates/events/off_waitlist_email.html b/hknweb/events/templates/events/off_waitlist_email.html
@@ -0,0 +1,24 @@
+<!DOCTYPE html>
+<html lang="en">
+<head>
+ <meta charset="UTF-8">
+ <title>{{ subject }}</title>
+</head>
+<body>
+
+ <p>
+ You have gotten off the waitlist for the event {{ event_name }}!
+ Click
+ <a href="{{ event_link }}">here</a>
+ to view the event.
+ </p>
+
+ <p>
+ Have a nice day!
+ </p>
+
+ <img src="{{ img_link }}" alt="cute animal"><br>
+ <span style="font-size: 0.8em;"> Image source: pexels.com </span>
+
+</body>
+</html>
diff --git a/hknweb/events/views.py b/hknweb/events/views.py
@@ -1,10 +1,13 @@
 from django.shortcuts import render, redirect
 from django.http import Http404
 from django.contrib import messages
-from django.shortcuts import get_object_or_404
+from django.shortcuts import get_object_or_404, reverse
+from django.core.mail import EmailMultiAlternatives
+from django.conf import settings
+from django.template.loader import render_to_string
 from django.views import generic
 
-from hknweb.utils import login_and_permission, method_login_and_permission
+from hknweb.utils import login_and_permission, method_login_and_permission, get_rand_photo
 from .models import Event, EventType, Rsvp
 from .forms import EventForm
 
@@ -75,11 +78,14 @@ def unrsvp(request, id):
  raise Http404()
 
  event = get_object_or_404(Event, pk=id)
- rsvp = get_object_or_404(Rsvp, user=request.user, event = event)
+ rsvp = get_object_or_404(Rsvp, user=request.user, event=event)
  if rsvp.confirmed:
  messages.error(request, 'Cannot un-rsvp from event you have gone to.')
  else:
+ old_admitted = set(event.admitted_set())
  rsvp.delete()
+ for off_waitlist_rsvp in event.newly_off_waitlist_rsvps(old_admitted):
+ send_off_waitlist_email(request, off_waitlist_rsvp.user, event)
  return redirect(event)
 
 @login_and_permission('events.add_event')
@@ -105,3 +111,29 @@ class EventUpdateView(generic.edit.UpdateView):
  'description', 'rsvp_limit']
  template_name_suffix = '_edit'
 
+ def form_valid(self, form):
+ if 'rsvp_limit' in form.changed_data:
+ messages.success(self.request, "People who rsvp'd or are on the waitlist are not notified"
+ " when you change the rsvp limit. Be sure to make an announcement!")
+ return super().form_valid(form)
+
+# Helpers
+
+def send_off_waitlist_email(request, user, event):
+ subject = '[HKN] You have gotten off the waitlist for your event'
+
+ event_link = request.build_absolute_uri(
+ reverse("events:detail", kwargs={ 'id': event.id }))
+ html_content = render_to_string(
+ 'events/off_waitlist_email.html',
+ {
+ 'subject': subject,
+ 'event_name': event.name,
+ 'event_link': event_link,
+ 'img_link': get_rand_photo(),
+ }
+ )
+ msg = EmailMultiAlternatives(subject, subject,
+ settings.NO_REPLY_EMAIL, [user.email])
+ msg.attach_alternative(html_content, "text/html")
+ msg.send()