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