hooke/playlist.py

   1 # Copyright (C) 2010 W. Trevor King <wking@drexel.edu>
   2 #
   3 # This file is part of Hooke.
   4 #
   5 # Hooke is free software: you can redistribute it and/or modify it
   6 # under the terms of the GNU Lesser General Public License as
   7 # published by the Free Software Foundation, either version 3 of the
   8 # License, or (at your option) any later version.
   9 #
  10 # Hooke is distributed in the hope that it will be useful, but WITHOUT
  11 # ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  12 # or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General
  13 # Public License for more details.
  14 #
  15 # You should have received a copy of the GNU Lesser General Public
  16 # License along with Hooke.  If not, see
  17 # <http://www.gnu.org/licenses/>.
  18
  19 """The `playlist` module provides a :class:`Playlist` and its subclass
  20 :class:`FilePlaylist` for manipulating lists of
  21 :class:`hooke.curve.Curve`\s.
  22 """
  23
  24 import copy
  25 import hashlib
  26 import os
  27 import os.path
  28 import types
  29
  30 import yaml
  31 from yaml.representer import RepresenterError
  32
  33 from .command_stack import CommandStack
  34 from .curve import Curve
  35 from .util.itertools import reverse_enumerate
  36
  37
  38 class NoteIndexList (list):
  39     """A list that keeps track of a "current" item and additional notes.
  40
  41     :attr:`index` (i.e. "bookmark") is the index of the currently
  42     current curve.  Also keep a :class:`dict` of additional information
  43     (:attr:`info`).
  44     """
  45     def __init__(self, name=None):
  46         super(NoteIndexList, self).__init__()
  47         self._set_default_attrs()
  48         self.__setstate__({'name': name})
  49
  50     def __str__(self):
  51         return str(self.__unicode__())
  52
  53     def __unicode__(self):
  54         return u'<%s %s>' % (self.__class__.__name__, self.name)
  55
  56     def __repr__(self):
  57         return self.__str__()
  58
  59     def _set_default_attrs(self):
  60         self._default_attrs = {
  61             'info': {},
  62             'name': None,
  63             '_index': 0,
  64             }
  65
  66     def __getstate__(self):
  67         return self.__dict__.copy()
  68
  69     def __setstate__(self, state):
  70         self._set_default_attrs()
  71         if state == True:
  72             return
  73         self.__dict__.update(self._default_attrs)
  74         try:
  75             self.__dict__.update(state)
  76         except TypeError, e:
  77             print state, type(state), e
  78         if self.info in [None, {}]:
  79             self.info = {}
  80
  81     def _setup_item(self, item):
  82         """Perform any required initialization before returning an item.
  83         """
  84         pass
  85
  86     def index(self, value=None, *args, **kwargs):
  87         """Extend `list.index`, returning the current index if `value`
  88         is `None`.
  89         """
  90         if value == None:
  91             return self._index
  92         return super(NoteIndexList, self).index(value, *args, **kwargs)
  93
  94     def current(self):
  95         if len(self) == 0:
  96             return None
  97         item = self[self._index]
  98         self._setup_item(item)
  99         return item
 100
 101     def jump(self, index):
 102         if len(self) == 0:
 103             self._index = 0
 104         else:
 105             self._index = index % len(self)
 106
 107     def next(self):
 108         self.jump(self._index + 1)
 109
 110     def previous(self):
 111         self.jump(self._index - 1)
 112
 113     def items(self, reverse=False):
 114         """Iterate through `self` calling `_setup_item` on each item
 115         before yielding.
 116
 117         Notes
 118         -----
 119         Updates :attr:`_index` during the iteration so
 120         :func:`~hooke.plugin.curve.current_curve_callback` works as
 121         expected in :class:`~hooke.command.Command`\s called from
 122         :class:`~hooke.plugin.playlist.ApplyCommand`.  After the
 123         iteration completes, :attr:`_index` is restored to its
 124         original value.
 125         """
 126         index = self._index
 127         items = self
 128         if reverse == True:
 129             items = reverse_enumerate(self)
 130         else:
 131             items = enumerate(self)
 132         for i,item in items:
 133             self._index = i
 134             self._setup_item(item)
 135             yield item
 136         self._index = index
 137
 138     def filter(self, keeper_fn=lambda item:True, load_curves=True,
 139                *args, **kwargs):
 140         c = copy.deepcopy(self)
 141         if load_curves == True:
 142             items = c.items(reverse=True)
 143         else:
 144             items = reversed(c)
 145         for item in items:
 146             if keeper_fn(item, *args, **kwargs) != True:
 147                 c.remove(item)
 148         try: # attempt to maintain the same current item
 149             c._index = c.index(self.current())
 150         except ValueError:
 151             c._index = 0
 152         return c
 153
 154
 155 class Playlist (NoteIndexList):
 156     """A :class:`NoteIndexList` of :class:`hooke.Curve`\s.
 157
 158     Keeps a list of :attr:`drivers` for loading curves.
 159     """
 160     def __init__(self, drivers, name=None):
 161         super(Playlist, self).__init__(name=name)
 162         self.drivers = drivers
 163         self._max_loaded = 100 # curves to hold in memory simultaneously.
 164
 165     def _set_default_attrs(self):
 166         super(Playlist, self)._set_default_attrs()
 167         self._default_attrs['drivers'] = []
 168         # List of loaded curves, see :meth:`._setup_item`.
 169         self._default_attrs['_loaded'] = []
 170         self._default_attrs['_max_loaded'] = 100
 171
 172     def __setstate__(self, state):
 173         super(Playlist, self).__setstate__(state)
 174         if self.drivers in [None, {}]:
 175             self.drivers = []
 176         if self._loaded in [None, {}]:
 177             self._loaded = []
 178
 179     def append_curve(self, curve):
 180         self.append(curve)
 181
 182     def append_curve_by_path(self, path, info=None, identify=True, hooke=None):
 183         path = os.path.normpath(path)
 184         c = Curve(path, info=info)
 185         c.set_hooke(hooke)
 186         if identify == True:
 187             c.identify(self.drivers)
 188         self.append(c)
 189         return c
 190
 191     def _setup_item(self, curve):
 192         if curve != None and curve not in self._loaded:
 193             if curve not in self:
 194                 self.append(curve)
 195             if curve.driver == None:
 196                 c.identify(self.drivers)
 197             if curve.data == None:
 198                 curve.load()
 199             self._loaded.append(curve)
 200             if len(self._loaded) > self._max_loaded:
 201                 oldest = self._loaded.pop(0)
 202                 oldest.unload()
 203
 204
 205 class FilePlaylist (Playlist):
 206     """A file-backed :class:`Playlist`.
 207
 208     Examples
 209     --------
 210
 211     >>> p = FilePlaylist(drivers=['Driver A', 'Driver B'])
 212     >>> p.append(Curve('dummy/path/A'))
 213     >>> p.append(Curve('dummy/path/B'))
 214
 215     The data-type is pickleable, to ensure we can move it between
 216     processes with :class:`multiprocessing.Queue`\s.
 217
 218     >>> import pickle
 219     >>> s = pickle.dumps(p)
 220     >>> z = pickle.loads(s)
 221     >>> for curve in z:
 222     ...     print curve
 223     <Curve A>
 224     <Curve B>
 225     >>> print z.drivers
 226     ['Driver A', 'Driver B']
 227
 228     The data-type is also YAMLable (see :mod:`hooke.util.yaml`).
 229
 230     >>> s = yaml.dump(p)
 231     >>> z = yaml.load(s)
 232     >>> for curve in z:
 233     ...     print curve
 234     <Curve A>
 235     <Curve B>
 236     >>> print z.drivers
 237     ['Driver A', 'Driver B']
 238     """
 239     version = '0.2'
 240
 241     def __init__(self, drivers, name=None, path=None):
 242         super(FilePlaylist, self).__init__(drivers, name)
 243         self.path = self._base_path = None
 244         self.set_path(path)
 245         self.relative_curve_paths = True
 246         self._relative_curve_paths = False
 247
 248     def _set_default_attrs(self):
 249         super(FilePlaylist, self)._set_default_attrs()
 250         self._default_attrs['relative_curve_paths'] = True
 251         self._default_attrs['_relative_curve_paths'] = False
 252         self._default_attrs['_digest'] = None
 253
 254     def __getstate__(self):
 255         state = super(FilePlaylist, self).__getstate__()
 256         assert 'version' not in state, state
 257         state['version'] = self.version
 258         return state
 259
 260     def __setstate__(self, state):
 261         if 'version' in state:
 262             version = state.pop('version')
 263             assert version == FilePlaylist.version, (
 264                 'invalid version %s (%s) != %s (%s)'
 265                 % (version, type(version),
 266                    FilePlaylist.version, type(FilePlaylist.version)))
 267         super(FilePlaylist, self).__setstate__(state)
 268
 269     def set_path(self, path):
 270         orig_base_path = getattr(self, '_base_path', None)
 271         if path == None:
 272             if self._base_path == None:
 273                 self._base_path = os.getcwd()
 274         else:
 275             if not path.endswith('.hkp'):
 276                 path += '.hkp'
 277             self.path = path
 278             self._base_path = os.path.dirname(os.path.abspath(
 279                 os.path.expanduser(self.path)))
 280             if self.name == None:
 281                 self.name = os.path.basename(path)
 282         if self._base_path != orig_base_path:
 283             self.update_curve_paths()
 284
 285     def update_curve_paths(self):
 286         for curve in self:
 287             curve.set_path(self._curve_path(curve.path))
 288
 289     def _curve_path(self, path):
 290         if self._base_path == None:
 291             self._base_path = os.getcwd()
 292         path = os.path.join(self._base_path, path)
 293         if self._relative_curve_paths == True:
 294             path = os.path.relpath(path, self._base_path)
 295         return path
 296
 297     def append_curve(self, curve):
 298         curve.set_path(self._curve_path(curve.path))
 299         super(FilePlaylist, self).append_curve(curve)
 300
 301     def append_curve_by_path(self, path, *args, **kwargs):
 302         path = self._curve_path(path)
 303         super(FilePlaylist, self).append_curve_by_path(path, *args, **kwargs)
 304
 305     def is_saved(self):
 306         return self.digest() == self._digest
 307
 308     def digest(self):
 309         r"""Compute the sha1 digest of the flattened playlist
 310         representation.
 311
 312         Examples
 313         --------
 314
 315         >>> root_path = os.path.sep + 'path'
 316         >>> p = FilePlaylist(drivers=[],
 317         ...                  path=os.path.join(root_path, 'to','playlist'))
 318         >>> p.info['note'] = 'An example playlist'
 319         >>> c = Curve(os.path.join(root_path, 'to', 'curve', 'one'))
 320         >>> c.info['note'] = 'The first curve'
 321         >>> p.append_curve(c)
 322         >>> c = Curve(os.path.join(root_path, 'to', 'curve', 'two'))
 323         >>> c.info['note'] = 'The second curve'
 324         >>> p.append_curve(c)
 325         >>> p.digest()
 326         'f\xe26i\xb98i\x1f\xb61J7:\xf2\x8e\x1d\xde\xc3}g'
 327         """
 328         string = self.flatten()
 329         return hashlib.sha1(string).digest()
 330
 331     def flatten(self):
 332         """Create a string representation of the playlist.
 333
 334         A playlist is a YAML document with the following minimal syntax::
 335
 336             !!python/object/new:hooke.playlist.FilePlaylist
 337             state:
 338               version: '0.2'
 339             listitems:
 340             - !!python/object:hooke.curve.Curve
 341               path: /path/to/curve/one
 342             - !!python/object:hooke.curve.Curve
 343               path: /path/to/curve/two
 344
 345         Relative paths are interpreted relative to the location of the
 346         playlist file.
 347
 348         Examples
 349         --------
 350
 351         >>> from .engine import CommandMessage
 352
 353         >>> root_path = os.path.sep + 'path'
 354         >>> p = FilePlaylist(drivers=[],
 355         ...                  path=os.path.join(root_path, 'to','playlist'))
 356         >>> p.info['note'] = 'An example playlist'
 357         >>> c = Curve(os.path.join(root_path, 'to', 'curve', 'one'))
 358         >>> c.info['note'] = 'The first curve'
 359         >>> p.append_curve(c)
 360         >>> c = Curve(os.path.join(root_path, 'to', 'curve', 'two'))
 361         >>> c.info['attr with spaces'] = 'The second curve\\nwith endlines'
 362         >>> c.command_stack.extend([
 363         ...         CommandMessage('command A', {'arg 0':0, 'arg 1':'X'}),
 364         ...         CommandMessage('command B', {'arg 0':1, 'curve':c}),
 365         ...         ])
 366         >>> p.append_curve(c)
 367         >>> print p.flatten()  # doctest: +REPORT_UDIFF
 368         # Hooke playlist version 0.2
 369         !!python/object/new:hooke.playlist.FilePlaylist
 370         listitems:
 371         - !!python/object:hooke.curve.Curve
 372           info: {note: The first curve}
 373           name: one
 374           path: curve/one
 375         - &id001 !!python/object:hooke.curve.Curve
 376           command_stack: !!python/object/new:hooke.command_stack.CommandStack
 377             listitems:
 378             - !!python/object:hooke.engine.CommandMessage
 379               arguments: {arg 0: 0, arg 1: X}
 380               command: command A
 381             - !!python/object:hooke.engine.CommandMessage
 382               arguments:
 383                 arg 0: 1
 384                 curve: *id001
 385               command: command B
 386           info: {attr with spaces: 'The second curve
 387         <BLANKLINE>
 388               with endlines'}
 389           name: two
 390           path: curve/two
 391         state:
 392           _base_path: /path/to
 393           info: {note: An example playlist}
 394           name: playlist.hkp
 395           path: /path/to/playlist.hkp
 396           version: '0.2'
 397         <BLANKLINE>
 398         >>> p.relative_curve_paths = False
 399         >>> print p.flatten()  # doctest: +REPORT_UDIFF
 400         # Hooke playlist version 0.2
 401         !!python/object/new:hooke.playlist.FilePlaylist
 402         listitems:
 403         - !!python/object:hooke.curve.Curve
 404           info: {note: The first curve}
 405           name: one
 406           path: /path/to/curve/one
 407         - &id001 !!python/object:hooke.curve.Curve
 408           command_stack: !!python/object/new:hooke.command_stack.CommandStack
 409             listitems:
 410             - !!python/object:hooke.engine.CommandMessage
 411               arguments: {arg 0: 0, arg 1: X}
 412               command: command A
 413             - !!python/object:hooke.engine.CommandMessage
 414               arguments:
 415                 arg 0: 1
 416                 curve: *id001
 417               command: command B
 418           info: {attr with spaces: 'The second curve
 419         <BLANKLINE>
 420               with endlines'}
 421           name: two
 422           path: /path/to/curve/two
 423         state:
 424           _base_path: /path/to
 425           info: {note: An example playlist}
 426           name: playlist.hkp
 427           path: /path/to/playlist.hkp
 428           relative_curve_paths: false
 429           version: '0.2'
 430         <BLANKLINE>
 431         """
 432         rcp = self._relative_curve_paths
 433         self._relative_curve_paths = self.relative_curve_paths
 434         self.update_curve_paths()
 435         self._relative_curve_paths = rcp
 436
 437         yaml_string = yaml.dump(self, allow_unicode=True)
 438         self.update_curve_paths()
 439         return ('# Hooke playlist version %s\n' % self.version) + yaml_string
 440
 441     def save(self, path=None, makedirs=True):
 442         """Saves the playlist to a YAML file.
 443         """
 444         self.set_path(path)
 445         dirname = os.path.dirname(self.path) or '.'
 446         if makedirs == True and not os.path.isdir(dirname):
 447             os.makedirs(dirname)
 448         with open(self.path, 'w') as f:
 449             f.write(self.flatten())
 450             self._digest = self.digest()
 451
 452
 453 def from_string(string):
 454     u"""Load a playlist from a string.
 455
 456     Examples
 457     --------
 458
 459     Minimal example.
 460
 461     >>> string = '''# Hooke playlist version 0.2
 462     ... !!python/object/new:hooke.playlist.FilePlaylist
 463     ... state:
 464     ...   version: '0.2'
 465     ... listitems:
 466     ... - !!python/object:hooke.curve.Curve
 467     ...   path: curve/one
 468     ... - !!python/object:hooke.curve.Curve
 469     ...   path: curve/two
 470     ... '''
 471     >>> p = from_string(string)
 472     >>> p.set_path('/path/to/playlist')
 473     >>> for curve in p:
 474     ...     print curve.name, curve.path
 475     one /path/to/curve/one
 476     two /path/to/curve/two
 477
 478     More complicated example.
 479
 480     >>> string = '''# Hooke playlist version 0.2
 481     ... !!python/object/new:hooke.playlist.FilePlaylist
 482     ... listitems:
 483     ... - !!python/object:hooke.curve.Curve
 484     ...   info: {note: The first curve}
 485     ...   name: one
 486     ...   path: /path/to/curve/one
 487     ... - &id001 !!python/object:hooke.curve.Curve
 488     ...   command_stack: !!python/object/new:hooke.command_stack.CommandStack
 489     ...     listitems:
 490     ...     - !!python/object:hooke.engine.CommandMessage
 491     ...       arguments: {arg 0: 0, arg 1: X}
 492     ...       command: command A
 493     ...     - !!python/object:hooke.engine.CommandMessage
 494     ...       arguments:
 495     ...         arg 0: 1
 496     ...         curve: *id001
 497     ...       command: command B
 498     ...   info: {attr with spaces: 'The second curve
 499     ...
 500     ...       with endlines'}
 501     ...   name: two
 502     ...   path: /path/to/curve/two
 503     ... state:
 504     ...   _base_path: /path/to
 505     ...   _index: 1
 506     ...   info: {note: An example playlist}
 507     ...   name: playlist.hkp
 508     ...   path: /path/to/playlist.hkp
 509     ...   version: '0.2'
 510     ... '''
 511     >>> p = from_string(string)
 512     >>> p.set_path('/path/to/playlist')
 513     >>> p._index
 514     1
 515     >>> p.info
 516     {'note': 'An example playlist'}
 517     >>> for curve in p:
 518     ...     print curve.name, curve.path
 519     one /path/to/curve/one
 520     two /path/to/curve/two
 521     >>> p[-1].info['attr with spaces']
 522     'The second curve\\nwith endlines'
 523     >>> type(p[-1].command_stack)
 524     <class 'hooke.command_stack.CommandStack'>
 525     >>> p[0].command_stack
 526     []
 527     >>> type(p[0].command_stack)
 528     <class 'hooke.command_stack.CommandStack'>
 529     >>> p[-1].command_stack  # doctest: +NORMALIZE_WHITESPACE
 530     [<CommandMessage command A {arg 0: 0, arg 1: X}>,
 531      <CommandMessage command B {arg 0: 1, curve: <Curve two>}>]
 532     >>> type(p[1].command_stack)
 533     <class 'hooke.command_stack.CommandStack'>
 534     >>> c2 = p[-1]
 535     >>> c2.command_stack[-1].arguments['curve'] == c2
 536     True
 537     """
 538     return yaml.load(string)
 539
 540 def load(path=None, identify=True, hooke=None):
 541     """Load a playlist from a file.
 542     """
 543     with open(self.path, 'r') as f:
 544         text = f.read()
 545     playlist = from_string(text)
 546     playlist._digest = playlist.digest()
 547     for curve in playlist:
 548         curve.set_hooke(hooke)
 549         if identify == True:
 550             curve.identify(playlist.drivers)
 551     return playlist
 552
 553
 554 class Playlists (NoteIndexList):
 555     """A :class:`NoteIndexList` of :class:`FilePlaylist`\s.
 556     """
 557     pass