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