+# Copyright (C) 2010 W. Trevor King <wking@drexel.edu>
+#
+# This file is part of Hooke.
+#
+# Hooke is free software: you can redistribute it and/or modify it
+# under the terms of the GNU Lesser General Public License as
+# published by the Free Software Foundation, either version 3 of the
+# License, or (at your option) any later version.
+#
+# Hooke is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+# or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General
+# Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with Hooke. If not, see
+# <http://www.gnu.org/licenses/>.
+
"""The `playlist` module provides a :class:`Playlist` and its subclass
:class:`FilePlaylist` for manipulating lists of
:class:`hooke.curve.Curve`\s.
import copy
import hashlib
import os.path
+import types
import xml.dom.minidom
from . import curve as curve
+from .compat import minidom as minidom # dynamically patch xml.sax.minidom
class NoteIndexList (list):
self.info = {}
self._index = 0
+ def __str__(self):
+ return '<%s %s>' % (self.__class__.__name__, self.name)
+
+ def _setup_item(self, item):
+ """Perform any required initialization before returning an item.
+ """
+ pass
+
+ def index(self, value=None, *args, **kwargs):
+ """Extend `list.index`, returning the current index if `value`
+ is `None`.
+ """
+ if value == None:
+ return self._index
+ return super(NoteIndexList, self).index(value, *args, **kwargs)
+
def current(self):
if len(self) == 0:
return None
- return self[self._index]
+ item = self[self._index]
+ self._setup_item(item)
+ return item
def jump(self, index):
if len(self) == 0:
def previous(self):
self.jump(self._index - 1)
- def filter(self, keeper_fn=lambda item:True):
+ def items(self, reverse=False):
+ """Iterate through `self` calling `_setup_item` on each item
+ before yielding.
+ """
+ items = self
+ if reverse == True:
+ items = reversed(self)
+ for item in items:
+ self._setup_item(item)
+ yield item
+
+ def filter(self, keeper_fn=lambda item:True, *args, **kwargs):
c = copy.deepcopy(self)
- for item in reversed(c):
- if keeper_fn(item) != True:
+ for item in c.items(reverse=True):
+ if keeper_fn(item, *args, **kwargs) != True:
c.remove(item)
try: # attempt to maintain the same current item
c._index = c.index(self.current())
def __init__(self, drivers, name=None):
super(Playlist, self).__init__(name=name)
self.drivers = drivers
+ self._loaded = [] # List of loaded curves, see :meth:`._setup_item`.
+ self._max_loaded = 100 # curves to hold in memory simultaneously.
def append_curve_by_path(self, path, info=None, identify=True):
if self.path != None:
- path = os.path.join(self.path, path)
+ path = os.path.join(os.path.dirname(self.path), path)
path = os.path.normpath(path)
c = curve.Curve(path, info=info)
if identify == True:
self.append(c)
return c
+ def _setup_item(self, curve):
+ if curve != None and curve not in self._loaded:
+ if curve not in self:
+ self.append(curve)
+ if curve.driver == None:
+ c.identify(self.drivers)
+ if curve.data == None:
+ curve.load()
+ self._loaded.append(curve)
+ if len(self._loaded) > self._max_loaded:
+ oldest = self._loaded.pop(0)
+ oldest.unload()
+
class FilePlaylist (Playlist):
version = '0.1'
super(FilePlaylist, self).__init__(drivers, name)
self.set_path(path)
self._digest = None
+ self._ignored_keys = [
+ 'experiment', # class instance, not very exciting.
+ ]
def set_path(self, path):
if path != None:
path += '.hkp'
self.path = path
if self.name == None:
- name = os.path.basename(path)
+ self.name = os.path.basename(path)
def is_saved(self):
return self.digest() == self._digest
>>> c.info['note'] = 'The second curve'
>>> p.append(c)
>>> p.digest()
- "\xa1\x99\x8a\x99\xed\xad\x13'\xa7w\x12\x00\x07Z\xb3\xd0zN\xa2\xe1"
+ '\\\x14\x87\x88*q\xf8\xaa\xa7\x84f\x82\xa1S>\xfd3+\xd0o'
"""
string = self.flatten()
return hashlib.sha1(string).digest()
+ def _clean_key(self, key):
+ """Replace spaces in keys with \\u00B7 (middle dot).
+
+ This character is deemed unlikely to occur in keys to our
+ playlist and curve info dictionaries, while many keys have
+ spaces in them.
+
+ \\u00B7 is allowed in XML 1.0 as of the 5th edition. See
+ the `4th edition errata`_ for details.
+
+ .. _4th edition errata:
+ http://www.w3.org/XML/xml-V10-4e-errata#E09
+ """
+ return key.replace(' ', u'\u00B7')
+
+ def _restore_key(self, key):
+ """Restore keys encoded with :meth:`_clean_key`.
+ """
+ return key.replace(u'\u00B7', ' ')
+
def flatten(self, absolute_paths=False):
"""Create a string representation of the playlist.
>>> c.info['note'] = 'The first curve'
>>> p.append(c)
>>> c = curve.Curve(os.path.join(root_path, 'to', 'curve', 'two'))
- >>> c.info['note'] = 'The second curve'
+ >>> c.info['attr with spaces'] = 'The second curve\\nwith endlines'
>>> p.append(c)
- >>> print p.flatten() # doctest: +NORMALIZE_WHITESPACE +REPORT_UDIFF
+ >>> def _print(string):
+ ... escaped_string = unicode(string, 'utf-8').encode('unicode escape')
+ ... print escaped_string.replace('\\\\n', '\\n').replace('\\\\t', '\\t'),
+ >>> _print(p.flatten()) # doctest: +NORMALIZE_WHITESPACE +REPORT_UDIFF
<?xml version="1.0" encoding="utf-8"?>
<playlist index="0" note="An example playlist" version="0.1">
- <curve note="The first curve" path="../curve/one"/>
- <curve note="The second curve" path="../curve/two"/>
+ <curve note="The first curve" path="curve/one"/>
+ <curve attr\\xb7with\\xb7spaces="The second curve
with endlines" path="curve/two"/>
</playlist>
- <BLANKLINE>
- >>> print p.flatten(absolute_paths=True) # doctest: +NORMALIZE_WHITESPACE +REPORT_UDIFF
+ >>> _print(p.flatten(absolute_paths=True)) # doctest: +NORMALIZE_WHITESPACE +REPORT_UDIFF
<?xml version="1.0" encoding="utf-8"?>
<playlist index="0" note="An example playlist" version="0.1">
- <curve note="The first curve" path="/path/to/curve/one"/>
- <curve note="The second curve" path="/path/to/curve/two"/>
+ <curve note="The first curve" path="/path/to/curve/one"/>
+ <curve attr\\xb7with\\xb7spaces="The second curve
with endlines" path="/path/to/curve/two"/>
</playlist>
- <BLANKLINE>
"""
implementation = xml.dom.minidom.getDOMImplementation()
# create the document DOM object and the root element
root.setAttribute('version', self.version) # store playlist version
root.setAttribute('index', str(self._index))
for key,value in self.info.items(): # save info variables
- root.setAttribute(key, str(value))
+ if (key in self._ignored_keys
+ or not isinstance(value, types.StringTypes)):
+ continue
+ root.setAttribute(self._clean_key(key), str(value))
for curve in self: # save curves and their attributes
curve_element = doc.createElement('curve')
root.appendChild(curve_element)
if absolute_paths == False:
path = os.path.relpath(
path,
- os.path.abspath(os.path.expanduser(self.path)))
+ os.path.dirname(
+ os.path.abspath(
+ os.path.expanduser(self.path))))
curve_element.setAttribute('path', path)
for key,value in curve.info.items():
- curve_element.setAttribute(key, str(value))
+ if (key in self._ignored_keys
+ or not isinstance(value, types.StringTypes)):
+ continue
+ curve_element.setAttribute(self._clean_key(key), str(value))
string = doc.toprettyxml(encoding='utf-8')
root.unlink() # break circular references for garbage collection
return string
- def _from_xml_doc(self, doc):
+ def _from_xml_doc(self, doc, identify=True):
"""Load a playlist from an :class:`xml.dom.minidom.Document`
instance.
"""
root = doc.documentElement
for attribute,value in root.attributes.items():
+ attribute = self._restore_key(attribute)
if attribute == 'version':
assert value == self.version, \
'Cannot read v%s playlist with a v%s reader' \
self.info[attribute] = value
for curve_element in doc.getElementsByTagName('curve'):
path = curve_element.getAttribute('path')
- info = dict(curve_element.attributes.items())
+ info = dict([(self._restore_key(key), value)
+ for key,value in curve_element.attributes.items()])
info.pop('path')
- self.append_curve_by_path(path, info, identify=False)
+ self.append_curve_by_path(path, info, identify=identify)
self.jump(self._index) # ensure valid index
- def from_string(self, string):
- """Load a playlist from a string.
+ def from_string(self, string, identify=True):
+ u"""Load a playlist from a string.
Examples
--------
>>> string = '''<?xml version="1.0" encoding="utf-8"?>
... <playlist index="1" note="An example playlist" version="0.1">
... <curve note="The first curve" path="../curve/one"/>
- ... <curve note="The second curve" path="../curve/two"/>
+ ... <curve attr\xb7with\xb7spaces="The second curve
with endlines" path="../curve/two"/>
... </playlist>
... '''
>>> p = FilePlaylist(drivers=[],
- ... path=os.path.join('path', 'to','playlist'))
- >>> p.from_string(string)
+ ... path=os.path.join('path', 'to', 'my', 'playlist'))
+ >>> p.from_string(string, identify=False)
>>> p._index
1
>>> p.info
... print curve.path
path/to/curve/one
path/to/curve/two
+ >>> p[-1].info['attr with spaces']
+ u'The second curve\\nwith endlines'
"""
doc = xml.dom.minidom.parseString(string)
- return self._from_xml_doc(doc)
+ self._from_xml_doc(doc, identify=identify)
- def load(self, path=None):
+ def load(self, path=None, identify=True):
"""Load a playlist from a file.
"""
self.set_path(path)
doc = xml.dom.minidom.parse(self.path)
- return self._from_xml_doc(doc)
+ self._from_xml_doc(doc, identify=identify)
+ self._digest = self.digest()
def save(self, path=None):
"""Saves the playlist in a XML file.