/usr/share/pyshared/zope/componentvocabulary/vocabulary.py is in python-zope.componentvocabulary 1.0.1-0ubuntu3.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 | ##############################################################################
#
# Copyright (c) 2004 Zope Foundation and Contributors.
# All Rights Reserved.
#
# This software is subject to the provisions of the Zope Public License,
# Version 2.1 (ZPL). A copy of the ZPL should accompany this distribution.
# THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED
# WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS
# FOR A PARTICULAR PURPOSE.
#
##############################################################################
"""Utility Vocabulary.
This vocabulary provides terms for all utilities providing a given interface.
"""
__docformat__ = "reStructuredText"
import zope.component
from zope.component.interface import interfaceToName
from zope.component.interfaces import IUtilityRegistration
from zope.interface import implements, classProvides, Interface, providedBy
from zope.interface.interfaces import IInterface
from zope.security.proxy import removeSecurityProxy
from zope.schema.interfaces import IVocabularyTokenized
from zope.schema.interfaces import ITokenizedTerm, ITitledTokenizedTerm
from zope.schema.interfaces import IVocabularyFactory
from zope.schema.vocabulary import SimpleVocabulary, SimpleTerm
from zope.componentvocabulary.i18n import ZopeMessageFactory as _
class UtilityTerm(object):
"""A term representing a utility.
The token of the term is the name of the utility. Here is a brief example
on how the IVocabulary interface is handled in this term as a
utility:
>>> from zope.interface.verify import verifyObject
>>> from zope.schema.interfaces import IVocabulary
>>> term = UtilityTerm(IVocabulary, 'zope.schema.interfaces.IVocabulary')
>>> verifyObject(ITokenizedTerm, term)
True
>>> term.value
<InterfaceClass zope.schema.interfaces.IVocabulary>
>>> term.token
'zope.schema.interfaces.IVocabulary'
>>> term
<UtilityTerm zope.schema.interfaces.IVocabulary, instance of InterfaceClass>
"""
implements(ITokenizedTerm)
def __init__(self, value, token):
"""Create a term for value and token."""
self.value = value
self.token = token
def __repr__(self):
return '<UtilityTerm %s, instance of %s>' %(
self.token, self.value.__class__.__name__)
class UtilityVocabulary(object):
"""Vocabulary that provides utilities of a specified interface.
Here is a short example of how the vocabulary should work.
First we need to create a utility interface and some utilities:
>>> class IObject(Interface):
... 'Simple interface to mark object utilities.'
>>>
>>> class Object(object):
... implements(IObject)
... def __init__(self, name):
... self.name = name
... def __repr__(self):
... return '<Object %s>' %self.name
Now we register some utilities for IObject
>>> from zope import component
>>> object1 = Object('object1')
>>> component.provideUtility(object1, IObject, 'object1')
>>> object2 = Object('object2')
>>> component.provideUtility(object2, IObject, 'object2')
>>> object3 = Object('object3')
>>> component.provideUtility(object3, IObject, 'object3')
>>> object4 = Object('object4')
We are now ready to create a vocabulary that we can use; in our case
everything is global, so the context is None.
>>> vocab = UtilityVocabulary(None, interface=IObject)
>>> import pprint
>>> pprint.pprint(vocab._terms.items())
[(u'object1', <UtilityTerm object1, instance of Object>),
(u'object2', <UtilityTerm object2, instance of Object>),
(u'object3', <UtilityTerm object3, instance of Object>)]
Now let's see how the other methods behave in this context. First we can
just use the 'in' opreator to test whether a value is available.
>>> object1 in vocab
True
>>> object4 in vocab
False
We can also create a lazy iterator. Note that the utility terms might
appear in a different order than the utilities were registered.
>>> iterator = iter(vocab)
>>> terms = list(iterator)
>>> names = [term.token for term in terms]
>>> names.sort()
>>> names
[u'object1', u'object2', u'object3']
Determining the amount of utilities available via the vocabulary is also
possible.
>>> len(vocab)
3
Next we are looking at some of the more vocabulary-characteristic API
methods.
One can get a term for a given value using ``getTerm()``:
>>> vocab.getTerm(object1)
<UtilityTerm object1, instance of Object>
>>> vocab.getTerm(object4)
Traceback (most recent call last):
...
LookupError: <Object object4>
On the other hand, if you want to get a term by the token, then you do
that with:
>>> vocab.getTermByToken('object1')
<UtilityTerm object1, instance of Object>
>>> vocab.getTermByToken('object4')
Traceback (most recent call last):
...
LookupError: object4
That's it. It is all pretty straight forward, but it allows us to easily
create a vocabulary for any utility. In fact, to make it easy to register
such a vocabulary via ZCML, the `interface` argument to the constructor
can be a string that is resolved via the utility registry. The ZCML looks
like this:
<zope:vocabulary
name='IObjects'
factory='zope.app.utility.vocabulary.UtilityVocabulary'
interface='zope.app.utility.vocabulary.IObject' />
>>> component.provideUtility(IObject, IInterface,
... 'zope.app.utility.vocabulary.IObject')
>>> vocab = UtilityVocabulary(
... None, interface='zope.app.utility.vocabulary.IObject')
>>> pprint.pprint(vocab._terms.items())
[(u'object1', <UtilityTerm object1, instance of Object>),
(u'object2', <UtilityTerm object2, instance of Object>),
(u'object3', <UtilityTerm object3, instance of Object>)]
Sometimes it is desirable to only select the name of a utility. For
this purpose a `nameOnly` argument was added to the constructor, in which
case the UtilityTerm's value is not the utility itself but the name of the
utility.
>>> vocab = UtilityVocabulary(None, interface=IObject, nameOnly=True)
>>> pprint.pprint([term.value for term in vocab])
[u'object1', u'object2', u'object3']
"""
implements(IVocabularyTokenized)
classProvides(IVocabularyFactory)
# override these in subclasses
interface = Interface
nameOnly = False
def __init__(self, context, **kw):
if kw:
# BBB 2006/02/24, to be removed after 12 months
# the 'interface' and 'nameOnly' parameters are supposed to be
# set as class-level attributes in custom subclasses now.
self.nameOnly = bool(kw.get('nameOnly', False))
interface = kw.get('interface', Interface)
if isinstance(interface, (str, unicode)):
interface = zope.component.getUtility(IInterface, interface)
self.interface = interface
utils = zope.component.getUtilitiesFor(self.interface, context)
self._terms = dict(
(name, UtilityTerm(self.nameOnly and name or util, name))
for name, util in utils)
def __contains__(self, value):
"""See zope.schema.interfaces.IBaseVocabulary"""
return value in (term.value for term in self._terms.values())
def getTerm(self, value):
"""See zope.schema.interfaces.IBaseVocabulary"""
try:
return [term for name, term in self._terms.items()
if term.value == value][0]
except IndexError:
raise LookupError(value)
def getTermByToken(self, token):
"""See zope.schema.interfaces.IVocabularyTokenized"""
try:
return self._terms[token]
except KeyError:
raise LookupError(token)
def __iter__(self):
"""See zope.schema.interfaces.IIterableVocabulary"""
# Sort the terms by the token (utility name)
values = self._terms.values()
values.sort(lambda x, y: cmp(x.token, y.token))
return iter(values)
def __len__(self):
"""See zope.schema.interfaces.IIterableVocabulary"""
return len(self._terms)
class InterfacesVocabulary(UtilityVocabulary):
classProvides(IVocabularyFactory)
interface = IInterface
class ObjectInterfacesVocabulary(SimpleVocabulary):
"""A vocabulary that provides a list of all interfaces that its context
provides.
Here a quick demonstration:
>>> from zope.interface import Interface, implements
>>> class I1(Interface):
... pass
>>> class I2(Interface):
... pass
>>> class I3(I2):
... pass
>>> class Object(object):
... implements(I3, I1)
>>> vocab = ObjectInterfacesVocabulary(Object())
>>> import pprint
>>> names = [term.token for term in vocab]
>>> names.sort()
>>> pprint.pprint(names)
['zope.componentvocabulary.vocabulary.I1',
'zope.componentvocabulary.vocabulary.I2',
'zope.componentvocabulary.vocabulary.I3',
'zope.interface.Interface']
"""
classProvides(IVocabularyFactory)
def __init__(self, context):
# Remove the security proxy so the values from the vocabulary
# are the actual interfaces and not proxies.
component = removeSecurityProxy(context)
interfaces = providedBy(component).flattened()
terms = [SimpleTerm(interface, interfaceToName(context, interface))
for interface in interfaces]
super(ObjectInterfacesVocabulary, self).__init__(terms)
class UtilityComponentInterfacesVocabulary(ObjectInterfacesVocabulary):
classProvides(IVocabularyFactory)
def __init__(self, context):
if IUtilityRegistration.providedBy(context):
context = context.component
super(UtilityComponentInterfacesVocabulary, self).__init__(
context)
class UtilityNameTerm:
r"""Simple term that provides a utility name as a value.
>>> t1 = UtilityNameTerm('abc')
>>> t2 = UtilityNameTerm(u'\xC0\xDF\xC7')
>>> t1.value
u'abc'
>>> t2.value
u'\xc0\xdf\xc7'
>>> t1.title
u'abc'
>>> repr(t2.title)
"u'\\xc0\\xdf\\xc7'"
>>> ITitledTokenizedTerm.providedBy(t1)
True
The tokens used for form values are Base-64 encodings of the
names, with the letter 't' prepended to ensure the unnamed utility
is supported:
>>> t1.token
'tYWJj'
>>> t2.token
'tw4DDn8OH'
The unnamed utility is given an artificial title for use in user
interfaces:
>>> t3 = UtilityNameTerm(u'')
>>> t3.title
u'(unnamed utility)'
"""
implements(ITitledTokenizedTerm)
def __init__(self, value):
self.value = unicode(value)
@property
def token(self):
# Return our value as a token. This is required to be 7-bit
# printable ascii. We'll use base64 generated from the UTF-8
# representation. (The default encoding rules should not be
# allowed to apply.)
return "t" + self.value.encode('utf-8').encode('base64')[:-1]
@property
def title(self):
return self.value or _("(unnamed utility)")
class UtilityNames:
"""Vocabulary with utility names for a single interface as values.
>>> class IMyUtility(Interface):
... pass
>>> class MyUtility(object):
... implements(IMyUtility)
>>> vocab = UtilityNames(IMyUtility)
>>> from zope.schema.interfaces import IVocabulary
>>> IVocabulary.providedBy(vocab)
True
>>> IVocabularyTokenized.providedBy(vocab)
True
>>> from zope.component.testing import PlacelessSetup
>>> from zope import component
>>> ps = PlacelessSetup()
>>> ps.setUp()
>>> component.provideUtility(MyUtility(), IMyUtility, 'one')
>>> component.provideUtility(MyUtility(), IMyUtility, 'two')
>>> unames = UtilityNames(IMyUtility)
>>> len(list(unames))
2
>>> L = [t.value for t in unames]
>>> L.sort()
>>> L
[u'one', u'two']
>>> u'one' in vocab
True
>>> u'three' in vocab
False
>>> component.provideUtility(MyUtility(), IMyUtility, 'three')
>>> u'three' in vocab
True
>>> component.provideUtility(MyUtility(), IMyUtility)
>>> u'' in vocab
True
>>> term1 = vocab.getTerm(u'')
>>> term2 = vocab.getTermByToken(term1.token)
>>> term2.value
u''
>>> term3 = vocab.getTerm(u'one')
>>> term3.token
'tb25l'
>>> term3a = vocab.getTermByToken('tb25l')
>>> term3.value
u'one'
>>> ps.tearDown()
"""
implements(IVocabularyTokenized)
def __init__(self, interface):
self.interface = interface
def __contains__(self, value):
return zope.component.queryUtility(self.interface, value) is not None
def getTerm(self, value):
if value in self:
return UtilityNameTerm(value)
raise ValueError(value)
def getTermByToken(self, token):
for name, ut in zope.component.getUtilitiesFor(self.interface):
name = unicode(name)
if token == "t":
if not name:
break
elif UtilityNameTerm(name).token == token:
break
else:
raise LookupError("no matching token: %r" % token)
return self.getTerm(name)
def __iter__(self):
for name, ut in zope.component.getUtilitiesFor(self.interface):
yield UtilityNameTerm(name)
def __len__(self):
"""Return the number of valid terms, or sys.maxint."""
return len(list(zope.component.getUtilitiesFor(self.interface)))
|