Initial commit

yksa_kit/middleware.py

@@ -0,0 +1,32 @@
+from __future__ import annotations
+
+from zoneinfo import ZoneInfo, ZoneInfoNotFoundError
+
+from django.utils import timezone
+
+
+class UserTimezoneMiddleware:
+    """Activate the visitor's selected timezone (defaults to UTC).
+
+    Everything is stored in UTC; this is the only place display time is chosen,
+    so a page that renders a naive local time is a bug in the template, not here.
+    """
+
+    SESSION_KEY = "user_timezone"
+    DEFAULT_TIMEZONE = "UTC"
+
+    def __init__(self, get_response):
+        self.get_response = get_response
+
+    def __call__(self, request):
+        tz_name = request.session.get(self.SESSION_KEY, self.DEFAULT_TIMEZONE)
+        try:
+            timezone.activate(ZoneInfo(tz_name))
+            request.current_timezone_name = tz_name
+        except (ZoneInfoNotFoundError, ValueError):
+            timezone.activate(ZoneInfo(self.DEFAULT_TIMEZONE))
+            request.current_timezone_name = self.DEFAULT_TIMEZONE
+
+        response = self.get_response(request)
+        timezone.deactivate()
+        return response