fixup

python/nav/django/settings.py

@@ -135,7 +135,7 @@
     'django.contrib.messages.middleware.MessageMiddleware',
 )
 
-SESSION_SERIALIZER = 'django.contrib.sessions.serializers.JSONSerializer'
+SESSION_SERIALIZER = 'nav.web.utils.NAVSessionJSONSerializer'
 SESSION_ENGINE = 'django.contrib.sessions.backends.db'
 SESSION_COOKIE_AGE = int(_webfront_config.get('sessions', {}).get('timeout', 3600))
 SESSION_COOKIE_NAME = 'nav_sessionid'

python/nav/web/utils.py

@@ -15,9 +15,11 @@
 #
 """Utils for views"""
 
-from django.http import HttpResponse
-
+from datetime import datetime
+import json
 
+from django.contrib.sessions.serializers import JSONSerializer
+from django.http import HttpResponse
 from django.views.generic.list import ListView
 
 
@@ -64,3 +66,40 @@ def wrapper(request, *args, **kwargs):
         return wrapper
 
     return wrap
+
+
+class DateTimeJSONEncoder(json.JSONEncoder):
+    def default(self, obj):
+        # See "Date Time String Format" in the ECMA-262 specification.
+        if isinstance(obj, datetime.datetime):
+            result = obj.isoformat()
+            if obj.microsecond:
+                result = result[:23] + result[26:]
+            if result.endswith("+00:00"):
+                result = result[:-6] + "Z"
+            return result
+        else:
+            return super().default(obj)
+
+
+def decode_datetime_from_json(self, s):
+    if set(('T', '-', ':')) < set(s):
+        # Potentially a datetime
+        new_s = s[:]
+        if s.endswith('Z'):
+            new_s = s[-1] + '+00:00'
+        try:
+            return datetime.fromisoformat(new_s)
+        except ValueError:
+            pass
+    return self.decode(s)
+
+
+class NAVSessionJSONSerializer(JSONSerializer):
+    def dumps(self, obj):
+        return json.dumps(obj, separators=(",", ":"), cls=DateTimeJSONEncoder).encode(
+            "latin-1"
+        )
+
+    def loads(self, data):
+        return json.loads(data.decode("latin-1"), object_hook=decode_datetime_from_json)