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