tasklib/task.py

   1 import copy
   2 import datetime
   3 import json
   4 import os
   5 import subprocess
   6 import tempfile
   7 import uuid
   8
   9
  10 DATE_FORMAT = '%Y%m%dT%H%M%SZ'
  11
  12 REPR_OUTPUT_SIZE = 10
  13
  14 PENDING = 'pending'
  15
  16
  17 class TaskWarriorException(Exception):
  18     pass
  19
  20
  21 class Task(object):
  22
  23     class DoesNotExist(Exception):
  24         pass
  25
  26     def __init__(self, warrior, data={}):
  27         self.warrior = warrior
  28         self._data = data
  29
  30     def __getitem__(self, key):
  31         return self._get_field(key)
  32
  33     def __setitem__(self, key, val):
  34         self._data[key] = val
  35
  36     def __unicode__(self):
  37         return self._data.get('description')
  38
  39     def _get_field(self, key):
  40         hydrate_func = getattr(self, 'deserialize_{0}'.format(key), lambda x:x)
  41         return hydrate_func(self._data.get(key))
  42
  43     def _set_field(self, key, value):
  44         dehydrate_func = getattr(self, 'serialize_{0}'.format(key), lambda x:x)
  45         self._data[key] = dehydrate_func(value)
  46
  47     def serialize_due(self, date):
  48         return date.strftime(DATE_FORMAT)
  49
  50     def deserialize_due(self, date_str):
  51         if not date_str:
  52             return None
  53         return datetime.datetime.strptime(date_str, DATE_FORMAT)
  54
  55     def regenerate_uuid(self):
  56         self['uuid'] = str(uuid.uuid4())
  57
  58     def delete(self):
  59         self.warrior.delete_task(self['uuid'])
  60
  61     def done(self):
  62         self.warrior.complete_task(self['uuid'])
  63
  64     def save(self, delete_first=True):
  65         if self['uuid'] and delete_first:
  66             self.delete()
  67         if not self['uuid'] or delete_first:
  68             self.regenerate_uuid()
  69         self.warrior.import_tasks([self._data])
  70
  71     __repr__ = __unicode__
  72
  73
  74 class TaskFilter(object):
  75     """
  76     A set of parameters to filter the task list with.
  77     """
  78
  79     def __init__(self, filter_params=()):
  80         self.filter_params = filter_params
  81
  82     def add_filter(self, param, value):
  83         self.filter_params += ((param, value),)
  84
  85     def get_filter_params(self):
  86         return self.filter_params
  87
  88     def clone(self):
  89         c = self.__class__()
  90         c.filter_params = tuple(self.filter_params)
  91         return c
  92
  93
  94 class TaskQuerySet(object):
  95     """
  96     Represents a lazy lookup for a task objects.
  97     """
  98
  99     def __init__(self, warrior=None, filter_obj=None):
 100         self.warrior = warrior
 101         self._result_cache = None
 102         self.filter_obj = filter_obj or TaskFilter()
 103
 104     def __deepcopy__(self, memo):
 105         """
 106         Deep copy of a QuerySet doesn't populate the cache
 107         """
 108         obj = self.__class__()
 109         for k,v in self.__dict__.items():
 110             if k in ('_iter','_result_cache'):
 111                 obj.__dict__[k] = None
 112             else:
 113                 obj.__dict__[k] = copy.deepcopy(v, memo)
 114         return obj
 115
 116     def __repr__(self):
 117         data = list(self[:REPR_OUTPUT_SIZE + 1])
 118         if len(data) > REPR_OUTPUT_SIZE:
 119             data[-1] = "...(remaining elements truncated)..."
 120         return repr(data)
 121
 122     def __len__(self):
 123         if self._result_cache is None:
 124             self._result_cache = list(self)
 125         return len(self._result_cache)
 126
 127     def __iter__(self):
 128         if self._result_cache is None:
 129             self._result_cache = self._execute()
 130         return iter(self._result_cache)
 131
 132     def __getitem__(self, k):
 133         if self._result_cache is None:
 134             self._result_cache = list(self)
 135         return self._result_cache.__getitem__(k)
 136
 137     def __bool__(self):
 138         if self._result_cache is not None:
 139             return bool(self._result_cache)
 140         try:
 141             next(iter(self))
 142         except StopIteration:
 143             return False
 144         return True
 145
 146     def __nonzero__(self):
 147         return type(self).__bool__(self)
 148
 149     def _clone(self, klass=None, **kwargs):
 150         if klass is None:
 151             klass = self.__class__
 152         filter_obj = self.filter_obj.clone()
 153         c = klass(warrior=self.warrior, filter_obj=filter_obj)
 154         c.__dict__.update(kwargs)
 155         return c
 156
 157     def _execute(self):
 158         """
 159         Fetch the tasks which match the current filters.
 160         """
 161         return self.warrior._execute_filter(self.filter_obj)
 162
 163     def all(self):
 164         """
 165         Returns a new TaskQuerySet that is a copy of the current one.
 166         """
 167         return self._clone()
 168
 169     def pending(self):
 170         return self.filter(status=PENDING)
 171
 172     def filter(self, **kwargs):
 173         """
 174         Returns a new TaskQuerySet with the given filters added.
 175         """
 176         clone = self._clone()
 177         for param, value in kwargs.items():
 178             clone.filter_obj.add_filter(param, value)
 179         return clone
 180
 181     def get(self, **kwargs):
 182         """
 183         Performs the query and returns a single object matching the given
 184         keyword arguments.
 185         """
 186         clone = self.filter(**kwargs)
 187         num = len(clone)
 188         if num == 1:
 189             return clone._result_cache[0]
 190         if not num:
 191             raise Task.DoesNotExist(
 192                 'Task matching query does not exist. '
 193                 'Lookup parameters were {0}'.format(kwargs))
 194         raise ValueError(
 195             'get() returned more than one Task -- it returned {0}! '
 196             'Lookup parameters were {1}'.format(num, kwargs))
 197
 198
 199 class TaskWarrior(object):
 200     DEFAULT_FILTERS = {
 201         'status': 'pending',
 202     }
 203
 204     def __init__(self, data_location='~/.task', create=True):
 205         if not os.path.exists(data_location):
 206             os.makedirs(data_location)
 207         self.config = {
 208             'data.location': os.path.expanduser(data_location),
 209         }
 210         self.tasks = TaskQuerySet(self)
 211
 212     def _generate_command(self, command):
 213         args = ['task', 'rc:/']
 214         for item in self.config.items():
 215             args.append('rc.{0}={1}'.format(*item))
 216         args.append(command)
 217         return ' '.join(args)
 218
 219     def _execute_command(self, command):
 220         p = subprocess.Popen(self._generate_command(command), shell=True,
 221                              stdout=subprocess.PIPE, stderr=subprocess.PIPE)
 222         stdout, stderr = p.communicate()
 223         if p.returncode:
 224             raise TaskWarriorException(stderr.strip())
 225         return stdout.strip().split('\n')
 226
 227     def _format_filter_kwarg(self, kwarg):
 228         key, val = kwarg[0], kwarg[1]
 229         key = key.replace('__', '.')
 230         return '{0}:{1}'.format(key, val)
 231
 232     def _execute_filter(self, filter_obj):
 233         filter_commands = ' '.join(map(self._format_filter_kwarg,
 234                                        filter_obj.get_filter_params()))
 235         command = '{0} export'.format(filter_commands)
 236         tasks = []
 237         for line in self._execute_command(command):
 238             if line:
 239                 tasks.append(Task(self, json.loads(line.strip(','))))
 240         return tasks
 241
 242     def add_task(self, description, project=None):
 243         args = ['add', description]
 244         if project is not None:
 245             args.append('project:{0}'.format(project))
 246         self._execute_command(' '.join(args))
 247
 248     def delete_task(self, task_id):
 249         self._execute_command('{0} rc.confirmation:no delete'.format(task_id))
 250
 251     def complete_task(self, task_id):
 252         self._execute_command('{0} done'.format(task_id))
 253
 254     def import_tasks(self, tasks):
 255         fd, path = tempfile.mkstemp()
 256         with open(path, 'w') as f:
 257             f.write(json.dumps(tasks))
 258         self._execute_command('import {0}'.format(path))