Replace datetime.now() with timezone.now() in Django ORM queries.

When you pass a naive datetime to the Django ORM, it uses settings.TIME_ZONE
for the time zone. In the development environment, both settings.TIME_ZONE
and datetime.now() use 'America/New_York', so there is no change in behavior
there. (fromtimestamp with no tz argument uses the same timezone as
datetime.now)

We are soon going to change settings.TIME_ZONE to UTC, so need to remove
naive datetimes from queries to the ORM.

analytics/management/commands/active_user_stats.py

@@ -19,7 +19,7 @@ class Command(BaseCommand):
     def handle(self, *args, **options):
         # type: (*Any, **Any) -> None
         # Get list of all active users in the last 1 week
-        cutoff = datetime.now() - timedelta(minutes=30, hours=168)
+        cutoff = timezone.now() - timedelta(minutes=30, hours=168)
 
         users = UserPresence.objects.select_related().filter(timestamp__gt=cutoff)
 

analytics/management/commands/client_activity.py

@@ -6,6 +6,7 @@ from typing import Any
 from argparse import ArgumentParser
 from django.core.management.base import BaseCommand
 from django.db.models import Count, QuerySet
+from django.utils import timezone
 
 from zerver.models import UserActivity, UserProfile, Realm, \
     get_realm, get_user_profile_by_email
@@ -38,7 +39,7 @@ Usage examples:
         #
         # Importantly, this does NOT tell you anything about the relative
         # volumes of requests from clients.
-        threshold = datetime.datetime.now() - datetime.timedelta(days=7)
+        threshold = timezone.now() - datetime.timedelta(days=7)
         client_counts = user_activity_objects.filter(
             last_visit__gt=threshold).values("client__name").annotate(
             count=Count('client__name'))

zerver/lib/actions.py

@@ -445,7 +445,7 @@ def delete_realm_user_sessions(realm):
     # type: (Realm) -> None
     realm_user_ids = [user_profile.id for user_profile in
                       UserProfile.objects.filter(realm=realm)]
-    for session in Session.objects.filter(expire_date__gte=datetime.datetime.now()):
+    for session in Session.objects.filter(expire_date__gte=timezone.now()):
         if get_session_user(session) in realm_user_ids:
             delete_session(session)
 

zerver/management/commands/dump_messages.py

@@ -5,6 +5,7 @@ from typing import Any
 
 from optparse import make_option
 from django.core.management.base import BaseCommand, CommandParser
+from django.utils import timezone
 from zerver.models import get_realm, Message, Realm, Stream, Recipient
 
 import datetime
@@ -31,7 +32,7 @@ class Command(BaseCommand):
         streams = Stream.objects.filter(realm=realm, invite_only=False)
         recipients = Recipient.objects.filter(
             type=Recipient.STREAM, type_id__in=[stream.id for stream in streams])
-        cutoff = datetime.datetime.fromtimestamp(options["since"])
+        cutoff = datetime.datetime.fromtimestamp(options["since"], tz=timezone.utc)
         messages = Message.objects.filter(pub_date__gt=cutoff, recipient__in=recipients)
 
         for message in messages: