Task: Move TW-specific refresh behaviour to TW backend

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

diff --git a/tasklib/backends.py b/tasklib/backends.py
index e5562c6834c6f96f101c81a28e3b244023f202d3..92102cbb70f17efe471f818c99acb8e459d4336c 100644 (file)
--- a/tasklib/backends.py
+++ b/tasklib/backends.py
@@ -1,4 +1,5 @@
 import abc
+import json
 import os
 import re
 import subprocess
@@ -38,12 +39,28 @@ class Backend(object):
     def stop_task(self, task):
         pass
 
+    @abc.abstractmethod
+    def complete_task(self, task):
+        pass
+
+    @abc.abstractmethod
+    def refresh_task(self, task, after_save=False):
+        """
+        Refreshes the given task. Returns new data dict with serialized
+        attributes.
+        """
+        pass
+
     @abc.abstractmethod
     def sync(self):
         """Syncs the backend database with the taskd server"""
         pass
 
 
+class TaskWarriorException(Exception):
+    pass
+
+
 class TaskWarrior(object):
     def __init__(self, data_location=None, create=True, taskrc_location='~/.taskrc'):
         self.taskrc_location = os.path.expanduser(taskrc_location)
@@ -140,6 +157,17 @@ class TaskWarrior(object):
         if self.version < VERSION_2_4_2:
             self.execute_command(['next'], allow_failure=False)
 
+    def merge_with(self, path, push=False):
+        path = path.rstrip('/') + '/'
+        self.execute_command(['merge', path], config_override={
+            'merge.autopush': 'yes' if push else 'no',
+        })
+
+    def undo(self):
+        self.execute_command(['undo'])
+
+    # Backend interface implementation
+
     def filter_tasks(self, filter_obj):
         self.enforce_recurrence()
         args = ['export', '--'] + filter_obj.get_filter_params()
@@ -155,11 +183,89 @@ class TaskWarrior(object):
                     raise TaskWarriorException('Invalid JSON: %s' % data)
         return tasks
 
-    def merge_with(self, path, push=False):
-        path = path.rstrip('/') + '/'
-        self.execute_command(['merge', path], config_override={
-            'merge.autopush': 'yes' if push else 'no',
-        })
+    def save_task(self, task):
+        """Save a task into TaskWarrior database using add/modify call"""
+
+        args = [task['uuid'], 'modify'] if task.saved else ['add']
+        args.extend(task._get_modified_fields_as_args())
+        output = self.execute_command(args)
+
+        # Parse out the new ID, if the task is being added for the first time
+        if not task.saved:
+            id_lines = [l for l in output if l.startswith('Created task ')]
+
+            # Complain loudly if it seems that more tasks were created
+            # Should not happen
+            if len(id_lines) != 1 or len(id_lines[0].split(' ')) != 3:
+                raise TaskWarriorException("Unexpected output when creating "
+                                           "task: %s" % '\n'.join(id_lines))
+
+            # Circumvent the ID storage, since ID is considered read-only
+            identifier = id_lines[0].split(' ')[2].rstrip('.')
+
+            # Identifier can be either ID or UUID for completed tasks
+            try:
+                task._data['id'] = int(identifier)
+            except ValueError:
+                task._data['uuid'] = identifier
+
+        # Refreshing is very important here, as not only modification time
+        # is updated, but arbitrary attribute may have changed due hooks
+        # altering the data before saving
+        task.refresh(after_save=True)
+
+    def delete_task(self, task):
+        self.execute_command([task['uuid'], 'delete'])
+
+    def start_task(self, task):
+        self.execute_command([task['uuid'], 'start'])
+
+    def stop_task(self, task):
+        self.execute_command([task['uuid'], 'stop'])
+
+    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:
+            task.stop()
+
+        self.execute_command([task['uuid'], 'done'])
+
+    def refresh_task(self, task, after_save=False):
+        # We need to use ID as backup for uuid here for the refreshes
+        # of newly saved tasks. Any other place in the code is fine
+        # with using UUID only.
+        args = [task['uuid'] or task['id'], 'export']
+        output = self.execute_command(args)
+
+        def valid(output):
+            return len(output) == 1 and output[0].startswith('{')
+
+        # 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
+                and after_save):
+
+            # Make a copy, removing ID and UUID. It's most likely invalid
+            # (ID 0) if it failed to match a unique task.
+            data = copy.deepcopy(task._data)
+            data.pop('id', None)
+            data.pop('uuid', None)
+
+            taskfilter = TaskFilter(self)
+            for key, value in data.items():
+                taskfilter.add_filter_param(key, value)
+
+            output = self.execute_command(['export', '--'] +
+                taskfilter.get_filter_params())
+
+        # If more than 1 task has been matched still, raise an exception
+        if not valid(output):
+            raise TaskWarriorException(
+                "Unique identifiers {0} with description: {1} matches "
+                "multiple tasks: {2}".format(
+                task['uuid'] or task['id'], task['description'], output)
+            )
+
+        return json.loads(output[0])
 
-    def undo(self):
-        self.execute_command(['undo'])