Expose personal calendar in iCal format instead of provisioning Googl…

…e Calendars (#558)

hknweb/events/admin/__init__.py

@@ -1,16 +1,14 @@
-from hknweb.events.admin.attendance import (
- AttendanceFormAdmin,
- AttendanceResponseAdmin,
-)
+from django.contrib import admin
+
+from hknweb.events.admin.attendance import AttendanceFormAdmin, AttendanceResponseAdmin
+from hknweb.events.admin.event import EventAdmin
+from hknweb.events.admin.event_type import EventTypeAdmin
 from hknweb.events.admin.google_calendar import (
  GCalAccessLevelMappingAdmin,
  GoogleCalendarCredentialsAdmin,
 )
-from hknweb.events.admin.event import EventAdmin
-from hknweb.events.admin.event_type import EventTypeAdmin
+from hknweb.events.admin.ical_view import ICalViewAdmin
 from hknweb.events.admin.rsvp import RsvpAdmin
-
-from django.contrib import admin
 from hknweb.events.models import EventPhoto
 
 admin.site.register(EventPhoto)

hknweb/events/admin/ical_view.py

@@ -0,0 +1,14 @@
+from django.contrib import admin
+
+from hknweb.events.models import ICalView
+
+
+@admin.register(ICalView)
+class ICalViewAdmin(admin.ModelAdmin):
+ fields = ["user", "show_rsvpd", "show_not_rsvpd"]
+ list_display = ["id", "user"]
+ search_fields = [
+ "user__username",
+ "user__first_name",
+ "user__last_name",
+ ]

hknweb/events/migrations/0012_icalview.py

@@ -0,0 +1,39 @@
+# Generated by Django 4.2.5 on 2023-10-05 05:03
+
+from django.conf import settings
+from django.db import migrations, models
+import django.db.models.deletion
+import uuid
+
+
+class Migration(migrations.Migration):
+ dependencies = [
+ migrations.swappable_dependency(settings.AUTH_USER_MODEL),
+ ("events", "0011_eventphoto"),
+ ]
+
+ operations = [
+ migrations.CreateModel(
+ name="ICalView",
+ fields=[
+ (
+ "id",
+ models.UUIDField(
+ default=uuid.uuid4,
+ editable=False,
+ primary_key=True,
+ serialize=False,
+ ),
+ ),
+ ("show_rsvpd", models.BooleanField(default=True)),
+ ("show_not_rsvpd", models.BooleanField(default=False)),
+ (
+ "user",
+ models.ForeignKey(
+ on_delete=django.db.models.deletion.CASCADE,
+ to=settings.AUTH_USER_MODEL,
+ ),
+ ),
+ ],
+ ),
+ ]

hknweb/events/models/__init__.py

@@ -7,3 +7,4 @@
 )
 from hknweb.events.models.attendance import AttendanceForm, AttendanceResponse
 from hknweb.events.models.event_photo import EventPhoto
+from hknweb.events.models.ical_view import ICalView

hknweb/events/models/event.py

@@ -1,14 +1,14 @@
-from django.db import models
+import icalendar
 from django.contrib.auth.models import User
-
+from django.db import models
+from icalendar import vCalAddress, vText
 from markdownx.models import MarkdownxField
 
-from hknweb.utils import get_semester
 import hknweb.events.google_calendar_utils as gcal
-
+from hknweb.events.models.constants import ACCESS_LEVELS
 from hknweb.events.models.event_type import EventType
 from hknweb.events.models.google_calendar import GCalAccessLevelMapping
-from hknweb.events.models.constants import ACCESS_LEVELS
+from hknweb.utils import get_semester
 
 
 class Event(models.Model):
@@ -41,6 +41,29 @@ def semester(self):
  Example: "Spring 2020" """
  return get_semester(self.start_time)
 
+ def to_ical_obj(self):
+ event = icalendar.Event()
+ event.add("uid", self.id)
+ event.add("summary", self.name)
+ event.add("location", self.location)
+ event.add("description", self.description)
+ event.add("dtstart", self.start_time)
+ event.add("dtend", self.end_time)
+ event.add("dtstamp", self.created_at)
+
+ def make_attendee(user, status):
+ attendee = vCalAddress(f"MAILTO:{user.email}")
+ attendee.params["PARTSTAT"] = vText(status)
+ attendee.params["CN"] = vText(f"{user.first_name} {user.last_name}")
+ return attendee
+
+ for rsvp in self.admitted_set():
+ event.add("attendee", make_attendee(rsvp.user, "ACCEPTED"), encode=0)
+ for rsvp in self.waitlist_set():
+ event.add("attendee", make_attendee(rsvp.user, "TENTATIVE"), encode=0)
+
+ return event
+
  def get_absolute_url(self):
  return "/events/{}".format(self.id)
 

hknweb/events/models/ical_view.py

@@ -0,0 +1,63 @@
+import random
+import uuid
+from datetime import datetime, timedelta
+
+import icalendar
+from django.conf import settings
+from django.db import models
+from django.urls import reverse
+
+from hknweb.events.models import Event
+from hknweb.events.utils import get_events
+
+
+class ICalView(models.Model):
+ class Meta:
+ verbose_name = "iCal view"
+
+ id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
+ user = models.ForeignKey(settings.AUTH_USER_MODEL, on_delete=models.CASCADE)
+ show_rsvpd = models.BooleanField(default=True)
+ show_not_rsvpd = models.BooleanField(default=False)
+
+ @property
+ def url(self):
+ return reverse("events:ical", args=[self.id])
+
+ def to_ical_obj(self):
+ cal = icalendar.Calendar()
+ cal.add("prodid", "-//Eta Kappa Nu, Mu Chapter//Calendar//EN")
+ cal.add("version", "2.0")
+ cal.add("summary", f"HKN Personal Calendar for {self.user}")
+
+ events = get_events(self.user, self.show_rsvpd, self.show_not_rsvpd)
+ for event in events:
+ cal.add_component(event.to_ical_obj())
+
+ cal.add_component(self.dummy_event())
+ return cal
+
+ def dummy_event(self):
+ # Google Calendar doesn't let you configure how often to sync iCal feeds
+ # like Apple's Calendar app does. They say this can take up to 24 hours.
+
+ # According to https://webapps.stackexchange.com/a/66686, they probably
+ # look at how often the iCal feed itself changes and syncs more or less
+ # frequently based on that.
+
+ # So we add a dummy event in the far future that's randomized every time
+ # the feed is requested in hopes of making Google Calendar sync faster.
+
+ dt = datetime(3000, 1, 1) + timedelta(days=random.randrange(365))
+
+ event = icalendar.Event()
+ event.add("uid", "dummy")
+ event.add("summary", "Dummy Event")
+ event.add(
+ "description",
+ "Randomized dummy event to make Google Calendar sync faster",
+ )
+ event.add("dtstart", dt)
+ event.add("dtend", dt)
+ event.add("dtstamp", dt)
+ return event

hknweb/events/models/rsvp.py

@@ -1,9 +1,9 @@
-from django.db import models
 from django.contrib.auth.models import User
+from django.db import models
 
-from hknweb.models import Profile
-from hknweb.events.models.event import Event
 import hknweb.events.google_calendar_utils as gcal
+from hknweb.events.models.event import Event
+from hknweb.models import Profile
 
 
 class Rsvp(models.Model):
@@ -30,8 +30,10 @@ def has_not_rsvpd(cls, user, event):
  def save(self, *args, **kwargs):
  profile = Profile.objects.filter(user=self.user).first()
  if not profile.google_calendar_id:
- profile.google_calendar_id = gcal.create_personal_calendar()
- profile.save()
+ # we no longer provision new personal google calendars
+ # instead, we generate a ICalView and a route to view it
+ # so they can add it to any calendar app
+ return super().save(*args, **kwargs)
 
  if self.google_calendar_event_id is None:
  self.google_calendar_event_id = gcal.create_event(

hknweb/events/urls.py

@@ -1,11 +1,12 @@
 from django.urls import path
-import hknweb.events.views as views
 
+import hknweb.events.views as views
 
 app_name = "events"
 
 aggregate_display_urls = [
  path("", views.index, name="index"),
+ path("ical/<uuid:id>.ics", views.ical, name="ical"),
  path("leaderboard", views.get_leaderboard, name="leaderboard"),
  path("photos", views.photos, name="photos"),
 ]

hknweb/events/utils.py

@@ -7,6 +7,37 @@
 
 from hknweb.events.constants import ATTR
 from hknweb.events.models import Event
+from hknweb.utils import get_access_level
+
+
+def get_events(user, show_rsvpd, show_not_rsvpd):
+ """Retrieves the events a user can see.
+
+ Parameters
+ ----------
+ user: django.contrib.auth.models.User
+ The user authenticating the request (can be anonymous)
+ show_rsvpd: bool
+ Whether to include events the user has RSVP'd for
+ show_not_rsvpd: bool
+ Whether to include events the user has not RSVP'd for
+
+ Returns
+ -------
+ QuerySet of Event objects
+ """
+
+ events = Event.objects.order_by("-start_time").filter(
+ access_level__gte=get_access_level(user)
+ )
+
+ if user.is_authenticated:
+ if not show_rsvpd:
+ events = events.exclude(rsvp__user=user)
+ if not show_not_rsvpd:
+ events = events.filter(rsvp__user=user)
+
+ return events
 
 
 def create_event(data, start_time, end_time, user):

hknweb/events/views/__init__.py

@@ -1,5 +1,6 @@
 from hknweb.events.views.aggregate_displays import (
  index,
+ ical,
  get_leaderboard,
  photos,
 )

hknweb/events/views/aggregate_displays/__init__.py

@@ -1,3 +1,3 @@
-from hknweb.events.views.aggregate_displays.calendar import index
+from hknweb.events.views.aggregate_displays.calendar import ical, index
 from hknweb.events.views.aggregate_displays.leaderboard import get_leaderboard
 from hknweb.events.views.aggregate_displays.photos import photos

hknweb/events/views/aggregate_displays/calendar.py

@@ -1,12 +1,15 @@
+import uuid
 from typing import List
 
-from django.shortcuts import render
+from django.http import HttpResponse
+from django.shortcuts import get_object_or_404, render
 
-from hknweb.models import Profile
-from hknweb.events.models import Event, EventType, GCalAccessLevelMapping
+from hknweb.events.google_calendar_utils import SHARE_LINK_TEMPLATE, get_calendar_link
+from hknweb.events.models import Event, EventType, GCalAccessLevelMapping, ICalView
 from hknweb.events.models.constants import ACCESS_LEVELS
+from hknweb.events.utils import get_events
+from hknweb.models import Profile
 from hknweb.utils import allow_public_access, get_access_level
-from hknweb.events.google_calendar_utils import get_calendar_link
 
 
 @allow_public_access
@@ -28,6 +31,12 @@ def index(request):
  )
 
 
+@allow_public_access
+def ical(request, *, id: uuid.UUID):
+ ical_view = get_object_or_404(ICalView, pk=id)
+ return HttpResponse(ical_view.to_ical_obj().to_ical(), content_type="text/calendar")
+
+
 def calendar_helper(
  request,
  title,
@@ -37,15 +46,7 @@ def calendar_helper(
  show_sidebar=False,
 ):
  user_access_level = get_access_level(request.user)
-
- events = Event.objects.order_by("-start_time").filter(
- access_level__gte=user_access_level
- )
- if request.user.is_authenticated:
- if not rsvpd_display:
- events = events.exclude(rsvp__user=request.user)
- if not not_rsvpd_display:
- events = events.filter(rsvp__user=request.user)
+ events = get_events(request.user, rsvpd_display, not_rsvpd_display)
 
  all_event_types = event_types = EventType.objects.order_by("type")
  if event_type_types:
@@ -85,11 +86,21 @@ def get_calendars(request, user_access_level: int):
  if profile.google_calendar_id:
  calendars.append(
  {
- "name": "personal",
+ "name": "personal (gcal)",
  "link": get_calendar_link(calendar_id=profile.google_calendar_id),
  }
  )
 
+ ical_view, _ = ICalView.objects.get_or_create(user=request.user)
+ ical_url = request.build_absolute_uri(ical_view.url)
+ ical_url = ical_url.replace("https://", "webcal://")
+ calendars.append(
+ {
+ "name": "personal (ics)",
+ "link": SHARE_LINK_TEMPLATE.format(cid=ical_url),
+ }
+ )
+
  for calendar in calendars[:-1]:
  calendar["separator"] = "/"
  if len(calendars) > 0:

hknweb/settings/prod.py

@@ -25,3 +25,6 @@
 # https://docs.djangoproject.com/en/2.1/howto/static-files/
 STATIC_URL = "https://www.ocf.berkeley.edu/~hkn/hknweb/static/"
 STATIC_ROOT = "/home/h/hk/hkn/public_html/hknweb/static/"
+
+USE_X_FORWARDED_HOST = True
+SECURE_PROXY_SSL_HEADER = ("HTTP_X_FORWARDED_PROTO", "https")