TaskQuerySet: Always require backend set properly

[etc/taskwarrior.git] / tasklib / backends.py

diff --git a/tasklib/backends.py b/tasklib/backends.py
index 51285b544b8e31fd148b3f1ce3ff133f085fa6cd..dfef0a873328653ac15051b5039065432254a4fb 100644 (file)
--- a/tasklib/backends.py
+++ b/tasklib/backends.py
@@ -1,25 +1,26 @@
 import abc
+import datetime
 import json
+import logging
 import os
 import re
+import six
 import subprocess
 
-from tasklib.filters import TaskWarriorFilter
+from .task import Task, TaskQuerySet
+from .filters import TaskWarriorFilter
+from .serializing import local_zone
 
-VERSION_2_1_0 = six.u('2.1.0')
-VERSION_2_2_0 = six.u('2.2.0')
-VERSION_2_3_0 = six.u('2.3.0')
-VERSION_2_4_0 = six.u('2.4.0')
-VERSION_2_4_1 = six.u('2.4.1')
-VERSION_2_4_2 = six.u('2.4.2')
-VERSION_2_4_3 = six.u('2.4.3')
-VERSION_2_4_4 = six.u('2.4.4')
-VERSION_2_4_5 = six.u('2.4.5')
+DATE_FORMAT_CALC = '%Y-%m-%dT%H:%M:%S'
 
+logger = logging.getLogger(__name__)
 
 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):
@@ -67,12 +68,30 @@ class Backend(object):
         """Syncs the backend database with the taskd server"""
         pass
 
+    def convert_datetime_string(self, value):
+        """
+        Converts TW syntax datetime string to a localized datetime
+        object. This method is not mandatory.
+        """
+        raise NotImplemented
+
 
 class TaskWarriorException(Exception):
     pass
 
 
 class TaskWarrior(object):
+
+    VERSION_2_1_0 = six.u('2.1.0')
+    VERSION_2_2_0 = six.u('2.2.0')
+    VERSION_2_3_0 = six.u('2.3.0')
+    VERSION_2_4_0 = six.u('2.4.0')
+    VERSION_2_4_1 = six.u('2.4.1')
+    VERSION_2_4_2 = six.u('2.4.2')
+    VERSION_2_4_3 = six.u('2.4.3')
+    VERSION_2_4_4 = six.u('2.4.4')
+    VERSION_2_4_5 = six.u('2.4.5')
+
     def __init__(self, data_location=None, create=True, taskrc_location='~/.taskrc'):
         self.taskrc_location = os.path.expanduser(taskrc_location)
 
@@ -92,7 +111,7 @@ class TaskWarrior(object):
 
             # 2.4.3 onwards supports 0 as infite bulk, otherwise set just
             # arbitrary big number which is likely to be large enough
-            'bulk': 0 if self.version >= VERSION_2_4_3 else 100000,
+            'bulk': 0 if self.version >= self.VERSION_2_4_3 else 100000,
         }
 
         # Set data.location override if passed via kwarg
@@ -136,7 +155,7 @@ class TaskWarrior(object):
             else:
                 escaped_serialized_value = six.u("'{0}'").format(serialized_value)
 
-            format_default = lambda: six.u("{0}:{1}").format(field,
+            format_default = lambda task: six.u("{0}:{1}").format(field,
                                                       escaped_serialized_value)
 
             format_func = getattr(self, 'format_{0}'.format(field),
@@ -167,8 +186,8 @@ class TaskWarrior(object):
 
         old_dependencies = task._original_data.get('depends', set())
 
-        added = self['depends'] - old_dependencies
-        removed = old_dependencies - self['depends']
+        added = task['depends'] - old_dependencies
+        removed = old_dependencies - task['depends']
 
         # Removed dependencies need to be prefixed with '-'
         return 'depends:' + ','.join(
@@ -179,11 +198,28 @@ class TaskWarrior(object):
     def format_description(self, task):
         # Task version older than 2.4.0 ignores first word of the
         # task description if description: prefix is used
-        if self.version < VERSION_2_4_0:
+        if self.version < self.VERSION_2_4_0:
             return task._data['description']
         else:
             return six.u("description:'{0}'").format(task._data['description'] or '')
 
+    def convert_datetime_string(self, value):
+
+        if self.version >= self.VERSION_2_4_0:
+            # For strings, use 'task calc' to evaluate the string to datetime
+            # available since TW 2.4.0
+            args = value.split()
+            result = self.execute_command(['calc'] + args)
+            naive = datetime.datetime.strptime(result[0], DATE_FORMAT_CALC)
+            localized = local_zone.localize(naive)
+        else:
+            raise ValueError("Provided value could not be converted to "
+                             "datetime, its type is not supported: {}"
+                             .format(type(value)))
+
+    @property
+    def filter_class(self):
+        return TaskWarriorFilter
 
     # Public interface
 
@@ -231,7 +267,7 @@ class TaskWarrior(object):
         # of recurrent tasks.
 
         # Only necessary for TW up to 2.4.1, fixed in 2.4.2.
-        if self.version < VERSION_2_4_2:
+        if self.version < self.VERSION_2_4_2:
             self.execute_command(['next'], allow_failure=False)
 
     def merge_with(self, path, push=False):
@@ -302,7 +338,7 @@ class TaskWarrior(object):
 
     def complete_task(self, task):
         # Older versions of TW do not stop active task at completion
-        if self.version < VERSION_2_4_0 and task.active:
+        if self.version < self.VERSION_2_4_0 and task.active:
             task.stop()
 
         self.execute_command([task['uuid'], 'done'])
@@ -328,7 +364,7 @@ class TaskWarrior(object):
         # For older TW versions attempt to uniquely locate the task
         # using the data we have if it has been just saved.
         # This can happen when adding a completed task on older TW versions.
-        if (not valid(output) and self.version < VERSION_2_4_5
+        if (not valid(output) and self.version < self.VERSION_2_4_5
                 and after_save):
 
             # Make a copy, removing ID and UUID. It's most likely invalid