X-Git-Url: https://git.madduck.net/etc/taskwarrior.git/blobdiff_plain/73cb96ecbbcaf43f05dc825a1017c2680b79f5a9..e9ac4a95bfab8a3e323e15f5f26a6302a87384a3:/tasklib/backends.py

diff --git a/tasklib/backends.py b/tasklib/backends.py
index 2a00dee..0d01470 100644
--- a/tasklib/backends.py
+++ b/tasklib/backends.py
@@ -5,6 +5,9 @@ import re
 import subprocess
 
 from tasklib.filters import TaskWarriorFilter
+from tasklib.serializing import local_zone
+
+DATE_FORMAT_CALC = '%Y-%m-%dT%H:%M:%S'
 
 VERSION_2_1_0 = six.u('2.1.0')
 VERSION_2_2_0 = six.u('2.2.0')
@@ -19,7 +22,10 @@ VERSION_2_4_5 = six.u('2.4.5')
 
 class Backend(object):
 
-    filter_class = TaskWarriorFilter
+    @abc.abstractproperty
+    def filter_class(self):
+        """Returns the TaskFilter class used by this backend"""
+        pass
 
     @abc.abstractmethod
     def filter_tasks(self, filter_obj):
@@ -205,6 +211,10 @@ class TaskWarrior(object):
                              "datetime, its type is not supported: {}"
                              .format(type(value)))
 
+    @property
+    def filter_class(self):
+        return TaskWarriorFilter
+
     # Public interface
 
     def get_config(self):