Enable datetime localization for client

- Detect and store client timezone in cookies
- Add TimezoneMiddleware to activate localization based on cookies

Signed-off-by: Keshav Priyadarshi <git@keshav.space>

Author: keshav-space

fedcode/middleware.py

@@ -0,0 +1,30 @@
+#
+# Copyright (c) nexB Inc. and others. All rights reserved.
+# FederatedCode is a trademark of nexB Inc.
+# SPDX-License-Identifier: Apache-2.0
+# See http://www.apache.org/licenses/LICENSE-2.0 for the license text.
+# See https://github.com/nexB/federatedcode for support or download.
+# See https://aboutcode.org for more information about AboutCode.org OSS projects.
+#
+
+import zoneinfo
+
+from django.utils import timezone
+
+
+class TimezoneMiddleware:
+    def __init__(self, get_response):
+        self.get_response = get_response
+
+    def __call__(self, request):
+        try:
+            # Activate local timezone for user using cookies
+            tzname = request.COOKIES.get("user_timezone")
+            if tzname:
+                timezone.activate(zoneinfo.ZoneInfo(tzname))
+            else:
+                timezone.deactivate()
+        except Exception as e:
+            timezone.deactivate()
+
+        return self.get_response(request)

fedcode/templates/base.html

@@ -28,6 +28,13 @@
     </div>
 
     <script src="{% static 'js/notification.js' %}" defer></script>
+    <script>
+    // Since django can not determine the client’s time zone automatically.
+    // Store client's timezone in cookies to enable localization.
+    // https://docs.djangoproject.com/en/5.1/topics/i18n/timezones/#selecting-the-current-time-zone
+        const currentTimeZone = Intl.DateTimeFormat().resolvedOptions().timeZone;
+        document.cookie = "user_timezone=" + currentTimeZone;
+    </script>
     {% block scripts %}
     {% endblock %}
 </body>

federatedcode/settings.py

@@ -90,6 +90,7 @@
     "django.middleware.clickjacking.XFrameOptionsMiddleware",
     # OAUTH
     "oauth2_provider.middleware.OAuth2TokenMiddleware",
+    "fedcode.middleware.TimezoneMiddleware",
 ]
 
 ROOT_URLCONF = "federatedcode.urls"