tasklib/task.py

   1 from __future__ import print_function
   2 import copy
   3 import datetime
   4 import json
   5 import logging
   6 import os
   7 import six
   8 import subprocess
   9
  10 DATE_FORMAT = '%Y%m%dT%H%M%SZ'
  11 REPR_OUTPUT_SIZE = 10
  12 PENDING = 'pending'
  13 COMPLETED = 'completed'
  14
  15 VERSION_2_1_0 = six.u('2.1.0')
  16 VERSION_2_2_0 = six.u('2.2.0')
  17 VERSION_2_3_0 = six.u('2.3.0')
  18 VERSION_2_4_0 = six.u('2.4.0')
  19
  20 logger = logging.getLogger(__name__)
  21
  22
  23 class TaskWarriorException(Exception):
  24     pass
  25
  26
  27 class TaskResource(object):
  28     read_only_fields = []
  29
  30     def _load_data(self, data):
  31         self._data = data
  32         # We need to use a copy for original data, so that changes
  33         # are not propagated
  34         self._original_data = data.copy()
  35
  36     def __getitem__(self, key):
  37         # This is a workaround to make TaskResource non-iterable
  38         # over simple index-based iteration
  39         try:
  40             int(key)
  41             raise StopIteration
  42         except ValueError:
  43             pass
  44
  45         hydrate_func = getattr(self, 'deserialize_{0}'.format(key),
  46                                lambda x: x)
  47         return hydrate_func(self._data.get(key))
  48
  49     def __setitem__(self, key, value):
  50         if key in self.read_only_fields:
  51             raise RuntimeError('Field \'%s\' is read-only' % key)
  52         dehydrate_func = getattr(self, 'serialize_{0}'.format(key),
  53                                  lambda x: x)
  54         self._data[key] = dehydrate_func(value)
  55
  56     def __str__(self):
  57         s = six.text_type(self.__unicode__())
  58         if not six.PY3:
  59             s = s.encode('utf-8')
  60         return s
  61
  62     def __repr__(self):
  63         return str(self)
  64
  65
  66 class TaskAnnotation(TaskResource):
  67     read_only_fields = ['entry', 'description']
  68
  69     def __init__(self, task, data={}):
  70         self.task = task
  71         self._load_data(data)
  72
  73     def deserialize_entry(self, data):
  74         return datetime.datetime.strptime(data, DATE_FORMAT) if data else None
  75
  76     def serialize_entry(self, date):
  77         return date.strftime(DATE_FORMAT) if date else ''
  78
  79     def remove(self):
  80         self.task.remove_annotation(self)
  81
  82     def __unicode__(self):
  83         return self['description']
  84
  85     __repr__ = __unicode__
  86
  87
  88 class Task(TaskResource):
  89     read_only_fields = ['id', 'entry', 'urgency', 'uuid']
  90
  91     class DoesNotExist(Exception):
  92         pass
  93
  94     class CompletedTask(Exception):
  95         """
  96         Raised when the operation cannot be performed on the completed task.
  97         """
  98         pass
  99
 100     class DeletedTask(Exception):
 101         """
 102         Raised when the operation cannot be performed on the deleted task.
 103         """
 104         pass
 105
 106     class NotSaved(Exception):
 107         """
 108         Raised when the operation cannot be performed on the task, because
 109         it has not been saved to TaskWarrior yet.
 110         """
 111         pass
 112
 113     def __init__(self, warrior, data={}, **kwargs):
 114         self.warrior = warrior
 115
 116         # We keep data for backwards compatibility
 117         kwargs.update(data)
 118
 119         self._load_data(kwargs)
 120
 121     def __unicode__(self):
 122         return self['description']
 123
 124     def __eq__(self, other):
 125         return self['uuid'] == other['uuid']
 126
 127     def __hash__(self):
 128         return self['uuid'].__hash__()
 129
 130     @property
 131     def _modified_fields(self):
 132         for key in self._data.keys():
 133             if self._data.get(key) != self._original_data.get(key):
 134                 yield key
 135
 136     @property
 137     def completed(self):
 138         return self['status'] == six.text_type('completed')
 139
 140     @property
 141     def deleted(self):
 142         return self['status'] == six.text_type('deleted')
 143
 144     @property
 145     def waiting(self):
 146         return self['status'] == six.text_type('waiting')
 147
 148     @property
 149     def pending(self):
 150         return self['status'] == six.text_type('pending')
 151
 152     @property
 153     def saved(self):
 154         return self['uuid'] is not None or self['id'] is not None
 155
 156     def serialize_due(self, date):
 157         return date.strftime(DATE_FORMAT)
 158
 159     def deserialize_due(self, date_str):
 160         if not date_str:
 161             return None
 162         return datetime.datetime.strptime(date_str, DATE_FORMAT)
 163
 164     def deserialize_annotations(self, data):
 165         return [TaskAnnotation(self, d) for d in data] if data else []
 166
 167     def deserialize_tags(self, tags):
 168         if isinstance(tags, basestring):
 169             return tags.split(',') if tags else []
 170         return tags
 171
 172     def serialize_tags(self, tags):
 173         return ','.join(tags) if tags else ''
 174
 175     def delete(self):
 176         if not self.saved:
 177             raise Task.NotSaved("Task needs to be saved before it can be deleted")
 178
 179         # Refresh the status, and raise exception if the task is deleted
 180         self.refresh(only_fields=['status'])
 181
 182         if self.deleted:
 183             raise Task.DeletedTask("Task was already deleted")
 184
 185         self.warrior.execute_command([self['uuid'], 'delete'], config_override={
 186             'confirmation': 'no',
 187         })
 188
 189         # Refresh the status again, so that we have updated info stored
 190         self.refresh(only_fields=['status'])
 191
 192
 193     def done(self):
 194         if not self.saved:
 195             raise Task.NotSaved("Task needs to be saved before it can be completed")
 196
 197         # Refresh, and raise exception if task is already completed/deleted
 198         self.refresh(only_fields=['status'])
 199
 200         if self.completed:
 201             raise Task.CompletedTask("Cannot complete a completed task")
 202         elif self.deleted:
 203             raise Task.DeletedTask("Deleted task cannot be completed")
 204
 205         self.warrior.execute_command([self['uuid'], 'done'])
 206
 207         # Refresh the status again, so that we have updated info stored
 208         self.refresh(only_fields=['status'])
 209
 210     def save(self):
 211         args = [self['uuid'], 'modify'] if self.saved else ['add']
 212         args.extend(self._get_modified_fields_as_args())
 213         output = self.warrior.execute_command(args)
 214
 215         # Parse out the new ID, if the task is being added for the first time
 216         if not self.saved:
 217             id_lines = [l for l in output if l.startswith('Created task ')]
 218
 219             # Complain loudly if it seems that more tasks were created
 220             # Should not happen
 221             if len(id_lines) != 1 or len(id_lines[0].split(' ')) != 3:
 222                 raise TaskWarriorException("Unexpected output when creating "
 223                                            "task: %s" % '\n'.join(id_lines))
 224
 225             # Circumvent the ID storage, since ID is considered read-only
 226             self._data['id'] = int(id_lines[0].split(' ')[2].rstrip('.'))
 227
 228         self.refresh()
 229
 230     def add_annotation(self, annotation):
 231         if not self.saved:
 232             raise Task.NotSaved("Task needs to be saved to add annotation")
 233
 234         args = [self['uuid'], 'annotate', annotation]
 235         self.warrior.execute_command(args)
 236         self.refresh(only_fields=['annotations'])
 237
 238     def remove_annotation(self, annotation):
 239         if not self.saved:
 240             raise Task.NotSaved("Task needs to be saved to add annotation")
 241
 242         if isinstance(annotation, TaskAnnotation):
 243             annotation = annotation['description']
 244         args = [self['uuid'], 'denotate', annotation]
 245         self.warrior.execute_command(args)
 246         self.refresh(only_fields=['annotations'])
 247
 248     def _get_modified_fields_as_args(self):
 249         args = []
 250
 251         def add_field(field):
 252             # Task version older than 2.4.0 ignores first word of the
 253             # task description if description: prefix is used
 254             if self.warrior.version < VERSION_2_4_0 and field == 'description':
 255                 args.append(self._data[field])
 256             else:
 257                 args.append('{0}:{1}'.format(field, self._data[field]))
 258
 259         # If we're modifying saved task, simply pass on all modified fields
 260         if self.saved:
 261             for field in self._modified_fields:
 262                 add_field(field)
 263         # For new tasks, pass all fields that make sense
 264         else:
 265             for field in self._data.keys():
 266                 if field in self.read_only_fields:
 267                     continue
 268                 add_field(field)
 269
 270         return args
 271
 272     def refresh(self, only_fields=[]):
 273         # Raise error when trying to refresh a task that has not been saved
 274         if not self.saved:
 275             raise Task.NotSaved("Task needs to be saved to be refreshed")
 276
 277         # We need to use ID as backup for uuid here for the refreshes
 278         # of newly saved tasks. Any other place in the code is fine
 279         # with using UUID only.
 280         args = [self['uuid'] or self['id'], 'export']
 281         new_data = json.loads(self.warrior.execute_command(args)[0])
 282         if only_fields:
 283             to_update = dict(
 284                 [(k, new_data.get(k)) for k in only_fields])
 285             self._data.update(to_update)
 286             self._original_data.update(to_update)
 287         else:
 288             self._data = new_data
 289             # We need to create a clone for original_data though
 290             # Shallow copy is alright, since data dict uses only
 291             # primitive data types
 292             self._original_data = new_data.copy()
 293
 294
 295 class TaskFilter(object):
 296     """
 297     A set of parameters to filter the task list with.
 298     """
 299
 300     def __init__(self, filter_params=[]):
 301         self.filter_params = filter_params
 302
 303     def add_filter(self, filter_str):
 304         self.filter_params.append(filter_str)
 305
 306     def add_filter_param(self, key, value):
 307         key = key.replace('__', '.')
 308
 309         # Replace the value with empty string, since that is the
 310         # convention in TW for empty values
 311         value = value if value is not None else ''
 312
 313         # If we are filtering by uuid:, do not use uuid keyword
 314         # due to TW-1452 bug
 315         if key == 'uuid':
 316             self.filter_params.insert(0, value)
 317         else:
 318             self.filter_params.append('{0}:{1}'.format(key, value))
 319
 320     def get_filter_params(self):
 321         return [f for f in self.filter_params if f]
 322
 323     def clone(self):
 324         c = self.__class__()
 325         c.filter_params = list(self.filter_params)
 326         return c
 327
 328
 329 class TaskQuerySet(object):
 330     """
 331     Represents a lazy lookup for a task objects.
 332     """
 333
 334     def __init__(self, warrior=None, filter_obj=None):
 335         self.warrior = warrior
 336         self._result_cache = None
 337         self.filter_obj = filter_obj or TaskFilter()
 338
 339     def __deepcopy__(self, memo):
 340         """
 341         Deep copy of a QuerySet doesn't populate the cache
 342         """
 343         obj = self.__class__()
 344         for k, v in self.__dict__.items():
 345             if k in ('_iter', '_result_cache'):
 346                 obj.__dict__[k] = None
 347             else:
 348                 obj.__dict__[k] = copy.deepcopy(v, memo)
 349         return obj
 350
 351     def __repr__(self):
 352         data = list(self[:REPR_OUTPUT_SIZE + 1])
 353         if len(data) > REPR_OUTPUT_SIZE:
 354             data[-1] = "...(remaining elements truncated)..."
 355         return repr(data)
 356
 357     def __len__(self):
 358         if self._result_cache is None:
 359             self._result_cache = list(self)
 360         return len(self._result_cache)
 361
 362     def __iter__(self):
 363         if self._result_cache is None:
 364             self._result_cache = self._execute()
 365         return iter(self._result_cache)
 366
 367     def __getitem__(self, k):
 368         if self._result_cache is None:
 369             self._result_cache = list(self)
 370         return self._result_cache.__getitem__(k)
 371
 372     def __bool__(self):
 373         if self._result_cache is not None:
 374             return bool(self._result_cache)
 375         try:
 376             next(iter(self))
 377         except StopIteration:
 378             return False
 379         return True
 380
 381     def __nonzero__(self):
 382         return type(self).__bool__(self)
 383
 384     def _clone(self, klass=None, **kwargs):
 385         if klass is None:
 386             klass = self.__class__
 387         filter_obj = self.filter_obj.clone()
 388         c = klass(warrior=self.warrior, filter_obj=filter_obj)
 389         c.__dict__.update(kwargs)
 390         return c
 391
 392     def _execute(self):
 393         """
 394         Fetch the tasks which match the current filters.
 395         """
 396         return self.warrior.filter_tasks(self.filter_obj)
 397
 398     def all(self):
 399         """
 400         Returns a new TaskQuerySet that is a copy of the current one.
 401         """
 402         return self._clone()
 403
 404     def pending(self):
 405         return self.filter(status=PENDING)
 406
 407     def completed(self):
 408         return self.filter(status=COMPLETED)
 409
 410     def filter(self, *args, **kwargs):
 411         """
 412         Returns a new TaskQuerySet with the given filters added.
 413         """
 414         clone = self._clone()
 415         for f in args:
 416             clone.filter_obj.add_filter(f)
 417         for key, value in kwargs.items():
 418             clone.filter_obj.add_filter_param(key, value)
 419         return clone
 420
 421     def get(self, **kwargs):
 422         """
 423         Performs the query and returns a single object matching the given
 424         keyword arguments.
 425         """
 426         clone = self.filter(**kwargs)
 427         num = len(clone)
 428         if num == 1:
 429             return clone._result_cache[0]
 430         if not num:
 431             raise Task.DoesNotExist(
 432                 'Task matching query does not exist. '
 433                 'Lookup parameters were {0}'.format(kwargs))
 434         raise ValueError(
 435             'get() returned more than one Task -- it returned {0}! '
 436             'Lookup parameters were {1}'.format(num, kwargs))
 437
 438
 439 class TaskWarrior(object):
 440     def __init__(self, data_location='~/.task', create=True):
 441         data_location = os.path.expanduser(data_location)
 442         if create and not os.path.exists(data_location):
 443             os.makedirs(data_location)
 444         self.config = {
 445             'data.location': os.path.expanduser(data_location),
 446         }
 447         self.tasks = TaskQuerySet(self)
 448         self.version = self._get_version()
 449
 450     def _get_command_args(self, args, config_override={}):
 451         command_args = ['task', 'rc:/']
 452         config = self.config.copy()
 453         config.update(config_override)
 454         for item in config.items():
 455             command_args.append('rc.{0}={1}'.format(*item))
 456         command_args.extend(map(str, args))
 457         return command_args
 458
 459     def _get_version(self):
 460         p = subprocess.Popen(
 461                 ['task', '--version'],
 462                 stdout=subprocess.PIPE,
 463                 stderr=subprocess.PIPE)
 464         stdout, stderr = [x.decode('utf-8') for x in p.communicate()]
 465         return stdout.strip('\n')
 466
 467     def execute_command(self, args, config_override={}):
 468         command_args = self._get_command_args(
 469             args, config_override=config_override)
 470         logger.debug(' '.join(command_args))
 471         p = subprocess.Popen(command_args, stdout=subprocess.PIPE,
 472                              stderr=subprocess.PIPE)
 473         stdout, stderr = [x.decode('utf-8') for x in p.communicate()]
 474         if p.returncode:
 475             if stderr.strip():
 476                 error_msg = stderr.strip().splitlines()[-1]
 477             else:
 478                 error_msg = stdout.strip()
 479             raise TaskWarriorException(error_msg)
 480         return stdout.strip().split('\n')
 481
 482     def filter_tasks(self, filter_obj):
 483         args = ['export', '--'] + filter_obj.get_filter_params()
 484         tasks = []
 485         for line in self.execute_command(args):
 486             if line:
 487                 data = line.strip(',')
 488                 try:
 489                     tasks.append(Task(self, json.loads(data)))
 490                 except ValueError:
 491                     raise TaskWarriorException('Invalid JSON: %s' % data)
 492         return tasks
 493
 494     def merge_with(self, path, push=False):
 495         path = path.rstrip('/') + '/'
 496         self.execute_command(['merge', path], config_override={
 497             'merge.autopush': 'yes' if push else 'no',
 498         })
 499
 500     def undo(self):
 501         self.execute_command(['undo'], config_override={
 502             'confirmation': 'no',
 503         })