hooke/playlist.py

   1 # Copyright (C) 2010-2011 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, load=True):
  95         if len(self) == 0:
  96             return None
  97         item = self[self._index]
  98         if load == True:
  99             self._setup_item(item)
 100         return item
 101
 102     def jump(self, index):
 103         if len(self) == 0:
 104             self._index = 0
 105         else:
 106             self._index = index % len(self)
 107
 108     def next(self):
 109         self.jump(self._index + 1)
 110
 111     def previous(self):
 112         self.jump(self._index - 1)
 113
 114     def items(self, reverse=False):
 115         """Iterate through `self` calling `_setup_item` on each item
 116         before yielding.
 117
 118         Notes
 119         -----
 120         Updates :attr:`_index` during the iteration so
 121         :func:`~hooke.plugin.curve.current_curve_callback` works as
 122         expected in :class:`~hooke.command.Command`\s called from
 123         :class:`~hooke.plugin.playlist.ApplyCommand`.  After the
 124         iteration completes, :attr:`_index` is restored to its
 125         original value.
 126         """
 127         index = self._index
 128         items = self
 129         if reverse == True:
 130             # could iterate through `c` if current_curve_callback()
 131             # would work, but `c` is not bound to the local `hooke`,
 132             # so curent_playlist_callback cannot point to it.
 133             items = reverse_enumerate(self)
 134         else:
 135             items = enumerate(self)
 136         for i,item in items:
 137             self._index = i
 138             self._setup_item(item)
 139             yield item
 140         self._index = index
 141
 142     def filter(self, keeper_fn=lambda item:True, load_curves=True,
 143                *args, **kwargs):
 144         c = copy.copy(self)
 145         if load_curves == True:
 146             items = self.items(reverse=True)
 147         else:
 148             items = reversed(self)
 149         for item in items:
 150             if keeper_fn(item, *args, **kwargs) != True:
 151                 c.remove(item)
 152         try: # attempt to maintain the same current item
 153             c._index = c.index(self.current())
 154         except ValueError:
 155             c._index = 0
 156         return c
 157
 158
 159 class Playlist (NoteIndexList):
 160     """A :class:`NoteIndexList` of :class:`hooke.Curve`\s.
 161
 162     Keeps a list of :attr:`drivers` for loading curves.
 163     """
 164     def __init__(self, drivers, name=None):
 165         super(Playlist, self).__init__(name=name)
 166         self.drivers = drivers
 167
 168     def _set_default_attrs(self):
 169         super(Playlist, self)._set_default_attrs()
 170         self._default_attrs['drivers'] = []
 171         # List of loaded curves, see :meth:`._setup_item`.
 172         self._default_attrs['_loaded'] = []
 173         self._default_attrs['_max_loaded'] = 100  # curves to hold in memory simultaneously.
 174
 175     def __setstate__(self, state):
 176         super(Playlist, self).__setstate__(state)
 177         if self.drivers in [None, {}]:
 178             self.drivers = []
 179         if self._loaded in [None, {}]:
 180             self._loaded = []
 181
 182     def append_curve(self, curve):
 183         self.append(curve)
 184
 185     def append_curve_by_path(self, path, info=None, identify=True, hooke=None):
 186         path = os.path.normpath(path)
 187         c = Curve(path, info=info)
 188         c.set_hooke(hooke)
 189         if identify == True:
 190             c.identify(self.drivers)
 191         self.append(c)
 192         return c
 193
 194     def _setup_item(self, curve):
 195         if curve != None and curve not in self._loaded:
 196             if curve not in self:
 197                 self.append(curve)
 198             if curve.driver == None:
 199                 c.identify(self.drivers)
 200             if curve.data == None or max([d.size for d in curve.data]) == 0:
 201                 curve.load()
 202             self._loaded.append(curve)
 203             if len(self._loaded) > self._max_loaded:
 204                 oldest = self._loaded.pop(0)
 205                 oldest.unload()
 206
 207     def unload(self, curve):
 208         "Inverse of `._setup_item`."
 209         curve.unload()
 210         try:
 211             self._loaded.remove(curve)
 212         except ValueError:
 213             pass
 214
 215
 216 def playlist_path(path):
 217     """Normalize playlist path extensions.
 218
 219     Examples
 220     --------
 221     >>> print playlist_path('playlist')
 222     playlist.hkp
 223     >>> print playlist_path('playlist.hkp')
 224     playlist.hkp
 225     >>> print playlist_path(None)
 226     None
 227     """
 228     if path == None:
 229         return None
 230     if not path.endswith('.hkp'):
 231         path += '.hkp'
 232     return path
 233
 234
 235 class FilePlaylist (Playlist):
 236     """A file-backed :class:`Playlist`.
 237
 238     Examples
 239     --------
 240
 241     >>> p = FilePlaylist(drivers=['Driver A', 'Driver B'])
 242     >>> p.append(Curve('dummy/path/A'))
 243     >>> p.append(Curve('dummy/path/B'))
 244
 245     The data-type is pickleable, to ensure we can move it between
 246     processes with :class:`multiprocessing.Queue`\s.
 247
 248     >>> import pickle
 249     >>> s = pickle.dumps(p)
 250     >>> z = pickle.loads(s)
 251     >>> for curve in z:
 252     ...     print curve
 253     <Curve A>
 254     <Curve B>
 255     >>> print z.drivers
 256     ['Driver A', 'Driver B']
 257
 258     The data-type is also YAMLable (see :mod:`hooke.util.yaml`).
 259
 260     >>> s = yaml.dump(p)
 261     >>> z = yaml.load(s)
 262     >>> for curve in z:
 263     ...     print curve
 264     <Curve A>
 265     <Curve B>
 266     >>> print z.drivers
 267     ['Driver A', 'Driver B']
 268     """
 269     version = '0.2'
 270
 271     def __init__(self, drivers, name=None, path=None):
 272         super(FilePlaylist, self).__init__(drivers, name)
 273         self.path = self._base_path = None
 274         self.set_path(path)
 275         self.relative_curve_paths = True
 276         self._relative_curve_paths = False
 277
 278     def _set_default_attrs(self):
 279         super(FilePlaylist, self)._set_default_attrs()
 280         self._default_attrs['relative_curve_paths'] = True
 281         self._default_attrs['_relative_curve_paths'] = False
 282         self._default_attrs['_digest'] = None
 283
 284     def __getstate__(self):
 285         state = super(FilePlaylist, self).__getstate__()
 286         assert 'version' not in state, state
 287         state['version'] = self.version
 288         return state
 289
 290     def __setstate__(self, state):
 291         if 'version' in state:
 292             version = state.pop('version')
 293             assert version == FilePlaylist.version, (
 294                 'invalid version %s (%s) != %s (%s)'
 295                 % (version, type(version),
 296                    FilePlaylist.version, type(FilePlaylist.version)))
 297         super(FilePlaylist, self).__setstate__(state)
 298
 299     def set_path(self, path):
 300         orig_base_path = getattr(self, '_base_path', None)
 301         if path == None:
 302             if self._base_path == None:
 303                 self._base_path = os.getcwd()
 304         else:
 305             path = playlist_path(path)
 306             self.path = path
 307             self._base_path = os.path.dirname(os.path.abspath(
 308                 os.path.expanduser(self.path)))
 309             if self.name == None:
 310                 self.name = os.path.basename(path)
 311         if self._base_path != orig_base_path:
 312             self.update_curve_paths()
 313
 314     def update_curve_paths(self):
 315         for curve in self:
 316             curve.set_path(self._curve_path(curve.path))
 317
 318     def _curve_path(self, path):
 319         if self._base_path == None:
 320             self._base_path = os.getcwd()
 321         path = os.path.join(self._base_path, path)
 322         if self._relative_curve_paths == True:
 323             path = os.path.relpath(path, self._base_path)
 324         return path
 325
 326     def append_curve(self, curve):
 327         curve.set_path(self._curve_path(curve.path))
 328         super(FilePlaylist, self).append_curve(curve)
 329
 330     def append_curve_by_path(self, path, *args, **kwargs):
 331         path = self._curve_path(path)
 332         super(FilePlaylist, self).append_curve_by_path(path, *args, **kwargs)
 333
 334     def is_saved(self):
 335         return self.digest() == self._digest
 336
 337     def digest(self):
 338         r"""Compute the sha1 digest of the flattened playlist
 339         representation.
 340
 341         Examples
 342         --------
 343
 344         >>> root_path = os.path.sep + 'path'
 345         >>> p = FilePlaylist(drivers=[],
 346         ...                  path=os.path.join(root_path, 'to','playlist'))
 347         >>> p.info['note'] = 'An example playlist'
 348         >>> c = Curve(os.path.join(root_path, 'to', 'curve', 'one'))
 349         >>> c.info['note'] = 'The first curve'
 350         >>> p.append_curve(c)
 351         >>> c = Curve(os.path.join(root_path, 'to', 'curve', 'two'))
 352         >>> c.info['note'] = 'The second curve'
 353         >>> p.append_curve(c)
 354         >>> p.digest()
 355         'f\xe26i\xb98i\x1f\xb61J7:\xf2\x8e\x1d\xde\xc3}g'
 356         """
 357         string = self.flatten()
 358         return hashlib.sha1(string).digest()
 359
 360     def flatten(self):
 361         """Create a string representation of the playlist.
 362
 363         A playlist is a YAML document with the following minimal syntax::
 364
 365             !!python/object/new:hooke.playlist.FilePlaylist
 366             state:
 367               version: '0.2'
 368             listitems:
 369             - !!python/object:hooke.curve.Curve
 370               path: /path/to/curve/one
 371             - !!python/object:hooke.curve.Curve
 372               path: /path/to/curve/two
 373
 374         Relative paths are interpreted relative to the location of the
 375         playlist file.
 376
 377         Examples
 378         --------
 379
 380         >>> from .engine import CommandMessage
 381
 382         >>> root_path = os.path.sep + 'path'
 383         >>> p = FilePlaylist(drivers=[],
 384         ...                  path=os.path.join(root_path, 'to','playlist'))
 385         >>> p.info['note'] = 'An example playlist'
 386         >>> c = Curve(os.path.join(root_path, 'to', 'curve', 'one'))
 387         >>> c.info['note'] = 'The first curve'
 388         >>> p.append_curve(c)
 389         >>> c = Curve(os.path.join(root_path, 'to', 'curve', 'two'))
 390         >>> c.info['attr with spaces'] = 'The second curve\\nwith endlines'
 391         >>> c.command_stack.extend([
 392         ...         CommandMessage('command A', {'arg 0':0, 'arg 1':'X'}),
 393         ...         CommandMessage('command B', {'arg 0':1, 'curve':c}),
 394         ...         ])
 395         >>> p.append_curve(c)
 396         >>> print p.flatten()  # doctest: +REPORT_UDIFF
 397         # Hooke playlist version 0.2
 398         !!python/object/new:hooke.playlist.FilePlaylist
 399         listitems:
 400         - !!python/object:hooke.curve.Curve
 401           info: {note: The first curve}
 402           name: one
 403           path: curve/one
 404         - &id001 !!python/object:hooke.curve.Curve
 405           command_stack: !!python/object/new:hooke.command_stack.CommandStack
 406             listitems:
 407             - !!python/object:hooke.engine.CommandMessage
 408               arguments: {arg 0: 0, arg 1: X}
 409               command: command A
 410               explicit_user_call: true
 411             - !!python/object:hooke.engine.CommandMessage
 412               arguments:
 413                 arg 0: 1
 414                 curve: *id001
 415               command: command B
 416               explicit_user_call: true
 417           info: {attr with spaces: 'The second curve
 418         <BLANKLINE>
 419               with endlines'}
 420           name: two
 421           path: curve/two
 422         state:
 423           _base_path: /path/to
 424           info: {note: An example playlist}
 425           name: playlist.hkp
 426           path: /path/to/playlist.hkp
 427           version: '0.2'
 428         <BLANKLINE>
 429         >>> p.relative_curve_paths = False
 430         >>> print p.flatten()  # doctest: +REPORT_UDIFF
 431         # Hooke playlist version 0.2
 432         !!python/object/new:hooke.playlist.FilePlaylist
 433         listitems:
 434         - !!python/object:hooke.curve.Curve
 435           info: {note: The first curve}
 436           name: one
 437           path: /path/to/curve/one
 438         - &id001 !!python/object:hooke.curve.Curve
 439           command_stack: !!python/object/new:hooke.command_stack.CommandStack
 440             listitems:
 441             - !!python/object:hooke.engine.CommandMessage
 442               arguments: {arg 0: 0, arg 1: X}
 443               command: command A
 444               explicit_user_call: true
 445             - !!python/object:hooke.engine.CommandMessage
 446               arguments:
 447                 arg 0: 1
 448                 curve: *id001
 449               command: command B
 450               explicit_user_call: true
 451           info: {attr with spaces: 'The second curve
 452         <BLANKLINE>
 453               with endlines'}
 454           name: two
 455           path: /path/to/curve/two
 456         state:
 457           _base_path: /path/to
 458           info: {note: An example playlist}
 459           name: playlist.hkp
 460           path: /path/to/playlist.hkp
 461           relative_curve_paths: false
 462           version: '0.2'
 463         <BLANKLINE>
 464         """
 465         rcp = self._relative_curve_paths
 466         self._relative_curve_paths = self.relative_curve_paths
 467         self.update_curve_paths()
 468         self._relative_curve_paths = rcp
 469         digest = self._digest
 470         self._digest = None  # don't save the digest (recursive file).
 471         yaml_string = yaml.dump(self, allow_unicode=True)
 472         self._digest = digest
 473         self.update_curve_paths()
 474         return ('# Hooke playlist version %s\n' % self.version) + yaml_string
 475
 476     def save(self, path=None, makedirs=True):
 477         """Saves the playlist to a YAML file.
 478         """
 479         self.set_path(path)
 480         dirname = os.path.dirname(self.path) or '.'
 481         if makedirs == True and not os.path.isdir(dirname):
 482             os.makedirs(dirname)
 483         with open(self.path, 'w') as f:
 484             f.write(self.flatten())
 485             self._digest = self.digest()
 486
 487
 488 def from_string(string):
 489     u"""Load a playlist from a string.
 490
 491     Examples
 492     --------
 493
 494     Minimal example.
 495
 496     >>> string = '''# Hooke playlist version 0.2
 497     ... !!python/object/new:hooke.playlist.FilePlaylist
 498     ... state:
 499     ...   version: '0.2'
 500     ... listitems:
 501     ... - !!python/object:hooke.curve.Curve
 502     ...   path: curve/one
 503     ... - !!python/object:hooke.curve.Curve
 504     ...   path: curve/two
 505     ... '''
 506     >>> p = from_string(string)
 507     >>> p.set_path('/path/to/playlist')
 508     >>> for curve in p:
 509     ...     print curve.name, curve.path
 510     one /path/to/curve/one
 511     two /path/to/curve/two
 512
 513     More complicated example.
 514
 515     >>> string = '''# Hooke playlist version 0.2
 516     ... !!python/object/new:hooke.playlist.FilePlaylist
 517     ... listitems:
 518     ... - !!python/object:hooke.curve.Curve
 519     ...   info: {note: The first curve}
 520     ...   name: one
 521     ...   path: /path/to/curve/one
 522     ... - &id001 !!python/object:hooke.curve.Curve
 523     ...   command_stack: !!python/object/new:hooke.command_stack.CommandStack
 524     ...     listitems:
 525     ...     - !!python/object:hooke.engine.CommandMessage
 526     ...       arguments: {arg 0: 0, arg 1: X}
 527     ...       command: command A
 528     ...     - !!python/object:hooke.engine.CommandMessage
 529     ...       arguments:
 530     ...         arg 0: 1
 531     ...         curve: *id001
 532     ...       command: command B
 533     ...   info: {attr with spaces: 'The second curve
 534     ...
 535     ...       with endlines'}
 536     ...   name: two
 537     ...   path: /path/to/curve/two
 538     ... state:
 539     ...   _base_path: /path/to
 540     ...   _index: 1
 541     ...   info: {note: An example playlist}
 542     ...   name: playlist.hkp
 543     ...   path: /path/to/playlist.hkp
 544     ...   version: '0.2'
 545     ... '''
 546     >>> p = from_string(string)
 547     >>> p.set_path('/path/to/playlist')
 548     >>> p._index
 549     1
 550     >>> p.info
 551     {'note': 'An example playlist'}
 552     >>> for curve in p:
 553     ...     print curve.name, curve.path
 554     one /path/to/curve/one
 555     two /path/to/curve/two
 556     >>> p[-1].info['attr with spaces']
 557     'The second curve\\nwith endlines'
 558     >>> type(p[-1].command_stack)
 559     <class 'hooke.command_stack.CommandStack'>
 560     >>> p[0].command_stack
 561     []
 562     >>> type(p[0].command_stack)
 563     <class 'hooke.command_stack.CommandStack'>
 564     >>> p[-1].command_stack  # doctest: +NORMALIZE_WHITESPACE
 565     [<CommandMessage command A {arg 0: 0, arg 1: X}>,
 566      <CommandMessage command B {arg 0: 1, curve: <Curve two>}>]
 567     >>> type(p[1].command_stack)
 568     <class 'hooke.command_stack.CommandStack'>
 569     >>> c2 = p[-1]
 570     >>> c2.command_stack[-1].arguments['curve'] == c2
 571     True
 572     """
 573     return yaml.load(string)
 574
 575 def load(path=None, drivers=None, identify=True, hooke=None):
 576     """Load a playlist from a file.
 577     """
 578     path = os.path.expanduser(playlist_path(path))
 579     with open(path, 'r') as f:
 580         text = f.read()
 581     playlist = from_string(text)
 582     playlist.set_path(path)
 583     playlist._digest = playlist.digest()
 584     if drivers != None:
 585         playlist.drivers = drivers
 586     playlist.set_path(path)
 587     for curve in playlist:
 588         curve.set_hooke(hooke)
 589         if identify == True:
 590             curve.identify(playlist.drivers)
 591     return playlist
 592
 593
 594 class Playlists (NoteIndexList):
 595     """A :class:`NoteIndexList` of :class:`FilePlaylist`\s.
 596     """
 597     pass