Coverage for python/lsst/daf/butler/core/storageClass.py: 47%
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1# This file is part of daf_butler.
2#
3# Developed for the LSST Data Management System.
4# This product includes software developed by the LSST Project
5# (http://www.lsst.org).
6# See the COPYRIGHT file at the top-level directory of this distribution
7# for details of code ownership.
8#
9# This program is free software: you can redistribute it and/or modify
10# it under the terms of the GNU General Public License as published by
11# the Free Software Foundation, either version 3 of the License, or
12# (at your option) any later version.
13#
14# This program is distributed in the hope that it will be useful,
15# but WITHOUT ANY WARRANTY; without even the implied warranty of
16# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17# GNU General Public License for more details.
18#
19# You should have received a copy of the GNU General Public License
20# along with this program. If not, see <http://www.gnu.org/licenses/>.
22from __future__ import annotations
24"""Support for Storage Classes."""
26__all__ = ("StorageClass", "StorageClassFactory", "StorageClassConfig")
28import builtins
29import copy
30import logging
31from typing import Any, Collection, Dict, List, Mapping, Optional, Sequence, Set, Tuple, Type, Union
33from lsst.utils import doImportType
34from lsst.utils.classes import Singleton
35from lsst.utils.introspection import get_full_type_name
37from .config import Config, ConfigSubset
38from .configSupport import LookupKey
39from .storageClassDelegate import StorageClassDelegate
41log = logging.getLogger(__name__)
44class StorageClassConfig(ConfigSubset):
45 """Configuration class for defining Storage Classes."""
47 component = "storageClasses"
48 defaultConfigFile = "storageClasses.yaml"
51class StorageClass:
52 """Class describing how a label maps to a particular Python type.
54 Parameters
55 ----------
56 name : `str`
57 Name to use for this class.
58 pytype : `type` or `str`
59 Python type (or name of type) to associate with the `StorageClass`
60 components : `dict`, optional
61 `dict` mapping name of a component to another `StorageClass`.
62 derivedComponents : `dict`, optional
63 `dict` mapping name of a derived component to another `StorageClass`.
64 parameters : `~collections.abc.Sequence` or `~collections.abc.Set`
65 Parameters understood by this `StorageClass` that can control
66 reading of data from datastores.
67 delegate : `str`, optional
68 Fully qualified name of class supporting assembly and disassembly
69 of a `pytype` instance.
70 converters : `dict` [`str`, `str`], optional
71 Mapping of python type to function that can be called to convert
72 that python type to the valid type of this storage class.
73 """
75 _cls_name: str = "BaseStorageClass"
76 _cls_components: Optional[Dict[str, StorageClass]] = None
77 _cls_derivedComponents: Optional[Dict[str, StorageClass]] = None
78 _cls_parameters: Optional[Union[Set[str], Sequence[str]]] = None
79 _cls_delegate: Optional[str] = None
80 _cls_pytype: Optional[Union[Type, str]] = None
81 _cls_converters: Optional[Dict[str, str]] = None
82 defaultDelegate: Type = StorageClassDelegate
83 defaultDelegateName: str = get_full_type_name(defaultDelegate)
85 def __init__(
86 self,
87 name: Optional[str] = None,
88 pytype: Optional[Union[Type, str]] = None,
89 components: Optional[Dict[str, StorageClass]] = None,
90 derivedComponents: Optional[Dict[str, StorageClass]] = None,
91 parameters: Optional[Union[Sequence, Set]] = None,
92 delegate: Optional[str] = None,
93 converters: Optional[Dict[str, str]] = None,
94 ):
95 if name is None:
96 name = self._cls_name
97 if pytype is None: 97 ↛ 99line 97 didn't jump to line 99, because the condition on line 97 was never false
98 pytype = self._cls_pytype
99 if components is None: 99 ↛ 101line 99 didn't jump to line 101, because the condition on line 99 was never false
100 components = self._cls_components
101 if derivedComponents is None: 101 ↛ 103line 101 didn't jump to line 103, because the condition on line 101 was never false
102 derivedComponents = self._cls_derivedComponents
103 if parameters is None: 103 ↛ 105line 103 didn't jump to line 105, because the condition on line 103 was never false
104 parameters = self._cls_parameters
105 if delegate is None: 105 ↛ 109line 105 didn't jump to line 109, because the condition on line 105 was never false
106 delegate = self._cls_delegate
108 # Merge converters with class defaults.
109 self._converters = {}
110 if self._cls_converters is not None:
111 self._converters.update(self._cls_converters)
112 if converters: 112 ↛ 113line 112 didn't jump to line 113, because the condition on line 112 was never true
113 self._converters.update(converters)
115 # Version of converters where the python types have been
116 # Do not try to import anything until needed.
117 self._converters_by_type: Optional[Dict[Type, Type]] = None
119 self.name = name
121 if pytype is None:
122 pytype = object
124 self._pytype: Optional[Type]
125 if not isinstance(pytype, str):
126 # Already have a type so store it and get the name
127 self._pytypeName = get_full_type_name(pytype)
128 self._pytype = pytype
129 else:
130 # Store the type name and defer loading of type
131 self._pytypeName = pytype
132 self._pytype = None
134 if components is not None:
135 if len(components) == 1: 135 ↛ 136line 135 didn't jump to line 136, because the condition on line 135 was never true
136 raise ValueError(
137 f"Composite storage class {name} is not allowed to have"
138 f" only one component '{next(iter(components))}'."
139 " Did you mean it to be a derived component?"
140 )
141 self._components = components
142 else:
143 self._components = {}
144 self._derivedComponents = derivedComponents if derivedComponents is not None else {}
145 self._parameters = frozenset(parameters) if parameters is not None else frozenset()
146 # if the delegate is not None also set it and clear the default
147 # delegate
148 self._delegate: Optional[Type]
149 self._delegateClassName: Optional[str]
150 if delegate is not None:
151 self._delegateClassName = delegate
152 self._delegate = None
153 elif components is not None: 153 ↛ 156line 153 didn't jump to line 156, because the condition on line 153 was never true
154 # We set a default delegate for composites so that a class is
155 # guaranteed to support something if it is a composite.
156 log.debug("Setting default delegate for %s", self.name)
157 self._delegate = self.defaultDelegate
158 self._delegateClassName = self.defaultDelegateName
159 else:
160 self._delegate = None
161 self._delegateClassName = None
163 @property
164 def components(self) -> Dict[str, StorageClass]:
165 """Return the components associated with this `StorageClass`."""
166 return self._components
168 @property
169 def derivedComponents(self) -> Dict[str, StorageClass]:
170 """Return derived components associated with `StorageClass`."""
171 return self._derivedComponents
173 @property
174 def converters(self) -> Dict[str, str]:
175 """Return the type converters supported by this `StorageClass`."""
176 return self._converters
178 @property
179 def converters_by_type(self) -> Dict[Type, Type]:
180 """Return the type converters as python types."""
181 if self._converters_by_type is None:
182 self._converters_by_type = {}
184 # Loop over list because the dict can be edited in loop.
185 for candidate_type_str, converter_str in list(self.converters.items()):
186 if hasattr(builtins, candidate_type_str):
187 candidate_type = getattr(builtins, candidate_type_str)
188 else:
189 try:
190 candidate_type = doImportType(candidate_type_str)
191 except ImportError as e:
192 log.warning(
193 "Unable to import type %s associated with storage class %s (%s)",
194 candidate_type_str,
195 self.name,
196 e,
197 )
198 del self.converters[candidate_type_str]
199 continue
201 try:
202 converter = doImportType(converter_str)
203 except ImportError as e:
204 log.warning(
205 "Unable to import conversion function %s associated with storage class %s "
206 "required to convert type %s (%s)",
207 converter_str,
208 self.name,
209 candidate_type_str,
210 e,
211 )
212 del self.converters[candidate_type_str]
213 continue
214 if not callable(converter):
215 # doImportType is annotated to return a Type but in actual
216 # fact it can return Any except ModuleType because package
217 # variables can be accessed. This make mypy believe it
218 # is impossible for the return value to not be a callable
219 # so we must ignore the warning.
220 log.warning( # type: ignore
221 "Conversion function %s associated with storage class "
222 "%s to convert type %s is not a callable.",
223 converter_str,
224 self.name,
225 candidate_type_str,
226 )
227 del self.converters[candidate_type_str]
228 continue
229 self._converters_by_type[candidate_type] = converter
230 return self._converters_by_type
232 @property
233 def parameters(self) -> Set[str]:
234 """Return `set` of names of supported parameters."""
235 return set(self._parameters)
237 @property
238 def pytype(self) -> Type:
239 """Return Python type associated with this `StorageClass`."""
240 if self._pytype is not None:
241 return self._pytype
243 if hasattr(builtins, self._pytypeName):
244 pytype = getattr(builtins, self._pytypeName)
245 else:
246 pytype = doImportType(self._pytypeName)
247 self._pytype = pytype
248 return self._pytype
250 @property
251 def delegateClass(self) -> Optional[Type]:
252 """Class to use to delegate type-specific actions."""
253 if self._delegate is not None:
254 return self._delegate
255 if self._delegateClassName is None:
256 return None
257 delegate_class = doImportType(self._delegateClassName)
258 self._delegate = delegate_class
259 return self._delegate
261 def allComponents(self) -> Mapping[str, StorageClass]:
262 """Return all defined components.
264 This mapping includes all the derived and read/write components
265 for the corresponding storage class.
267 Returns
268 -------
269 comp : `dict` of [`str`, `StorageClass`]
270 The component name to storage class mapping.
271 """
272 components = copy.copy(self.components)
273 components.update(self.derivedComponents)
274 return components
276 def delegate(self) -> StorageClassDelegate:
277 """Return an instance of a storage class delegate.
279 Returns
280 -------
281 delegate : `StorageClassDelegate`
282 Instance of the delegate associated with this `StorageClass`.
283 The delegate is constructed with this `StorageClass`.
285 Raises
286 ------
287 TypeError
288 This StorageClass has no associated delegate.
289 """
290 cls = self.delegateClass
291 if cls is None:
292 raise TypeError(f"No delegate class is associated with StorageClass {self.name}")
293 return cls(storageClass=self)
295 def isComposite(self) -> bool:
296 """Return Boolean indicating whether this is a composite or not.
298 Returns
299 -------
300 isComposite : `bool`
301 `True` if this `StorageClass` is a composite, `False`
302 otherwise.
303 """
304 if self.components:
305 return True
306 return False
308 def _lookupNames(self) -> Tuple[LookupKey, ...]:
309 """Keys to use when looking up this DatasetRef in a configuration.
311 The names are returned in order of priority.
313 Returns
314 -------
315 names : `tuple` of `LookupKey`
316 Tuple of a `LookupKey` using the `StorageClass` name.
317 """
318 return (LookupKey(name=self.name),)
320 def knownParameters(self) -> Set[str]:
321 """Return set of all parameters known to this `StorageClass`.
323 The set includes parameters understood by components of a composite.
325 Returns
326 -------
327 known : `set`
328 All parameter keys of this `StorageClass` and the component
329 storage classes.
330 """
331 known = set(self._parameters)
332 for sc in self.components.values():
333 known.update(sc.knownParameters())
334 return known
336 def validateParameters(self, parameters: Collection = None) -> None:
337 """Check that the parameters are known to this `StorageClass`.
339 Does not check the values.
341 Parameters
342 ----------
343 parameters : `~collections.abc.Collection`, optional
344 Collection containing the parameters. Can be `dict`-like or
345 `set`-like. The parameter values are not checked.
346 If no parameters are supplied, always returns without error.
348 Raises
349 ------
350 KeyError
351 Some parameters are not understood by this `StorageClass`.
352 """
353 # No parameters is always okay
354 if not parameters:
355 return
357 # Extract the important information into a set. Works for dict and
358 # list.
359 external = set(parameters)
361 diff = external - self.knownParameters()
362 if diff:
363 s = "s" if len(diff) > 1 else ""
364 unknown = "', '".join(diff)
365 raise KeyError(f"Parameter{s} '{unknown}' not understood by StorageClass {self.name}")
367 def filterParameters(self, parameters: Dict[str, Any], subset: Collection = None) -> Dict[str, Any]:
368 """Filter out parameters that are not known to this `StorageClass`.
370 Parameters
371 ----------
372 parameters : `dict`, optional
373 Candidate parameters. Can be `None` if no parameters have
374 been provided.
375 subset : `~collections.abc.Collection`, optional
376 Subset of supported parameters that the caller is interested
377 in using. The subset must be known to the `StorageClass`
378 if specified. If `None` the supplied parameters will all
379 be checked, else only the keys in this set will be checked.
381 Returns
382 -------
383 filtered : `dict`
384 Valid parameters. Empty `dict` if none are suitable.
386 Raises
387 ------
388 ValueError
389 Raised if the provided subset is not a subset of the supported
390 parameters or if it is an empty set.
391 """
392 if not parameters:
393 return {}
395 known = self.knownParameters()
397 if subset is not None:
398 if not subset:
399 raise ValueError("Specified a parameter subset but it was empty")
400 subset = set(subset)
401 if not subset.issubset(known):
402 raise ValueError(f"Requested subset ({subset}) is not a subset of known parameters ({known})")
403 wanted = subset
404 else:
405 wanted = known
407 return {k: parameters[k] for k in wanted if k in parameters}
409 def validateInstance(self, instance: Any) -> bool:
410 """Check that the supplied Python object has the expected Python type.
412 Parameters
413 ----------
414 instance : `object`
415 Object to check.
417 Returns
418 -------
419 isOk : `bool`
420 True if the supplied instance object can be handled by this
421 `StorageClass`, False otherwise.
422 """
423 return isinstance(instance, self.pytype)
425 def can_convert(self, other: StorageClass) -> bool:
426 """Return `True` if this storage class can convert python types
427 in the other storage class.
429 Parameters
430 ----------
431 other : `StorageClass`
432 The storage class to check.
434 Returns
435 -------
436 can : `bool`
437 `True` if this storage class has a registered converter for
438 the python type associated with the other storage class. That
439 converter will convert the other python type to the one associated
440 with this storage class.
441 """
442 if other.name == self.name:
443 # Identical storage classes are compatible.
444 return True
446 if issubclass(other.pytype, self.pytype):
447 # Storage classes have different names but the same python type.
448 return True
450 for candidate_type in self.converters_by_type:
451 if issubclass(other.pytype, candidate_type):
452 return True
453 return False
455 def coerce_type(self, incorrect: Any) -> Any:
456 """Coerce the supplied incorrect instance to the python type
457 associated with this `StorageClass`.
459 Parameters
460 ----------
461 incorrect : `object`
462 An object that might be the incorrect type.
464 Returns
465 -------
466 correct : `object`
467 An object that matches the python type of this `StorageClass`.
468 Can be the same object as given. If `None`, `None` will be
469 returned.
471 Raises
472 ------
473 TypeError
474 Raised if no conversion can be found.
475 """
476 if incorrect is None:
477 return None
479 # Possible this is the correct type already.
480 if self.validateInstance(incorrect):
481 return incorrect
483 # Check each registered converter.
484 for candidate_type, converter in self.converters_by_type.items():
485 if isinstance(incorrect, candidate_type):
486 try:
487 return converter(incorrect)
488 except Exception:
489 log.error(
490 "Converter %s failed to convert type %s",
491 get_full_type_name(converter),
492 get_full_type_name(incorrect),
493 )
494 raise
495 raise TypeError(
496 "Type does not match and no valid converter found to convert"
497 f" '{type(incorrect)}' to '{self.pytype}'"
498 )
500 def __eq__(self, other: Any) -> bool:
501 """Equality checks name, pytype name, delegate name, and components."""
502 if not isinstance(other, StorageClass):
503 return NotImplemented
505 if self.name != other.name:
506 return False
508 # We must compare pytype and delegate by name since we do not want
509 # to trigger an import of external module code here
510 if self._delegateClassName != other._delegateClassName:
511 return False
512 if self._pytypeName != other._pytypeName:
513 return False
515 # Ensure we have the same component keys in each
516 if set(self.components.keys()) != set(other.components.keys()):
517 return False
519 # Same parameters
520 if self.parameters != other.parameters:
521 return False
523 # Ensure that all the components have the same type
524 for k in self.components:
525 if self.components[k] != other.components[k]:
526 return False
528 # If we got to this point everything checks out
529 return True
531 def __hash__(self) -> int:
532 return hash(self.name)
534 def __repr__(self) -> str:
535 optionals: Dict[str, Any] = {}
536 if self._pytypeName != "object":
537 optionals["pytype"] = self._pytypeName
538 if self._delegateClassName is not None:
539 optionals["delegate"] = self._delegateClassName
540 if self._parameters:
541 optionals["parameters"] = self._parameters
542 if self.components:
543 optionals["components"] = self.components
544 if self.converters:
545 optionals["converters"] = self.converters
547 # order is preserved in the dict
548 options = ", ".join(f"{k}={v!r}" for k, v in optionals.items())
550 # Start with mandatory fields
551 r = f"{self.__class__.__name__}({self.name!r}"
552 if options:
553 r = r + ", " + options
554 r = r + ")"
555 return r
557 def __str__(self) -> str:
558 return self.name
561class StorageClassFactory(metaclass=Singleton):
562 """Factory for `StorageClass` instances.
564 This class is a singleton, with each instance sharing the pool of
565 StorageClasses. Since code can not know whether it is the first
566 time the instance has been created, the constructor takes no arguments.
567 To populate the factory with storage classes, a call to
568 `~StorageClassFactory.addFromConfig()` should be made.
570 Parameters
571 ----------
572 config : `StorageClassConfig` or `str`, optional
573 Load configuration. In a ButlerConfig` the relevant configuration
574 is located in the ``storageClasses`` section.
575 """
577 def __init__(self, config: Optional[Union[StorageClassConfig, str]] = None):
578 self._storageClasses: Dict[str, StorageClass] = {}
579 self._configs: List[StorageClassConfig] = []
581 # Always seed with the default config
582 self.addFromConfig(StorageClassConfig())
584 if config is not None: 584 ↛ 585line 584 didn't jump to line 585, because the condition on line 584 was never true
585 self.addFromConfig(config)
587 def __str__(self) -> str:
588 """Return summary of factory.
590 Returns
591 -------
592 summary : `str`
593 Summary of the factory status.
594 """
595 sep = "\n"
596 return f"""Number of registered StorageClasses: {len(self._storageClasses)}
598StorageClasses
599--------------
600{sep.join(f"{s}: {self._storageClasses[s]}" for s in self._storageClasses)}
601"""
603 def __contains__(self, storageClassOrName: Union[StorageClass, str]) -> bool:
604 """Indicate whether the storage class exists in the factory.
606 Parameters
607 ----------
608 storageClassOrName : `str` or `StorageClass`
609 If `str` is given existence of the named StorageClass
610 in the factory is checked. If `StorageClass` is given
611 existence and equality are checked.
613 Returns
614 -------
615 in : `bool`
616 True if the supplied string is present, or if the supplied
617 `StorageClass` is present and identical.
619 Notes
620 -----
621 The two different checks (one for "key" and one for "value") based on
622 the type of the given argument mean that it is possible for
623 StorageClass.name to be in the factory but StorageClass to not be
624 in the factory.
625 """
626 if isinstance(storageClassOrName, str): 626 ↛ 628line 626 didn't jump to line 628, because the condition on line 626 was never false
627 return storageClassOrName in self._storageClasses
628 elif isinstance(storageClassOrName, StorageClass):
629 if storageClassOrName.name in self._storageClasses:
630 return storageClassOrName == self._storageClasses[storageClassOrName.name]
631 return False
633 def addFromConfig(self, config: Union[StorageClassConfig, Config, str]) -> None:
634 """Add more `StorageClass` definitions from a config file.
636 Parameters
637 ----------
638 config : `StorageClassConfig`, `Config` or `str`
639 Storage class configuration. Can contain a ``storageClasses``
640 key if part of a global configuration.
641 """
642 sconfig = StorageClassConfig(config)
643 self._configs.append(sconfig)
645 # Since we can not assume that we will get definitions of
646 # components or parents before their classes are defined
647 # we have a helper function that we can call recursively
648 # to extract definitions from the configuration.
649 def processStorageClass(name: str, sconfig: StorageClassConfig) -> None:
650 # Maybe we've already processed this through recursion
651 if name not in sconfig:
652 return
653 info = sconfig.pop(name)
655 # Always create the storage class so we can ensure that
656 # we are not trying to overwrite with a different definition
657 components = None
659 # Extract scalar items from dict that are needed for
660 # StorageClass Constructor
661 storageClassKwargs = {k: info[k] for k in ("pytype", "delegate", "parameters") if k in info}
663 if "converters" in info:
664 storageClassKwargs["converters"] = info["converters"].toDict()
666 for compName in ("components", "derivedComponents"):
667 if compName not in info:
668 continue
669 components = {}
670 for cname, ctype in info[compName].items():
671 if ctype not in self:
672 processStorageClass(ctype, sconfig)
673 components[cname] = self.getStorageClass(ctype)
675 # Fill in other items
676 storageClassKwargs[compName] = components
678 # Create the new storage class and register it
679 baseClass = None
680 if "inheritsFrom" in info:
681 baseName = info["inheritsFrom"]
682 if baseName not in self: 682 ↛ 683line 682 didn't jump to line 683, because the condition on line 682 was never true
683 processStorageClass(baseName, sconfig)
684 baseClass = type(self.getStorageClass(baseName))
686 newStorageClassType = self.makeNewStorageClass(name, baseClass, **storageClassKwargs)
687 newStorageClass = newStorageClassType()
688 self.registerStorageClass(newStorageClass)
690 for name in list(sconfig.keys()):
691 processStorageClass(name, sconfig)
693 @staticmethod
694 def makeNewStorageClass(
695 name: str, baseClass: Optional[Type[StorageClass]] = StorageClass, **kwargs: Any
696 ) -> Type[StorageClass]:
697 """Create a new Python class as a subclass of `StorageClass`.
699 Parameters
700 ----------
701 name : `str`
702 Name to use for this class.
703 baseClass : `type`, optional
704 Base class for this `StorageClass`. Must be either `StorageClass`
705 or a subclass of `StorageClass`. If `None`, `StorageClass` will
706 be used.
708 Returns
709 -------
710 newtype : `type` subclass of `StorageClass`
711 Newly created Python type.
712 """
713 if baseClass is None:
714 baseClass = StorageClass
715 if not issubclass(baseClass, StorageClass): 715 ↛ 716line 715 didn't jump to line 716, because the condition on line 715 was never true
716 raise ValueError(f"Base class must be a StorageClass not {baseClass}")
718 # convert the arguments to use different internal names
719 clsargs = {f"_cls_{k}": v for k, v in kwargs.items() if v is not None}
720 clsargs["_cls_name"] = name
722 # Some container items need to merge with the base class values
723 # so that a child can inherit but override one bit.
724 # lists (which you get from configs) are treated as sets for this to
725 # work consistently.
726 for k in ("components", "parameters", "derivedComponents", "converters"):
727 classKey = f"_cls_{k}"
728 if classKey in clsargs:
729 baseValue = getattr(baseClass, classKey, None)
730 if baseValue is not None:
731 currentValue = clsargs[classKey]
732 if isinstance(currentValue, dict): 732 ↛ 735line 732 didn't jump to line 735, because the condition on line 732 was never false
733 newValue = baseValue.copy()
734 else:
735 newValue = set(baseValue)
736 newValue.update(currentValue)
737 clsargs[classKey] = newValue
739 # If we have parameters they should be a frozen set so that the
740 # parameters in the class can not be modified.
741 pk = "_cls_parameters"
742 if pk in clsargs:
743 clsargs[pk] = frozenset(clsargs[pk])
745 return type(f"StorageClass{name}", (baseClass,), clsargs)
747 def getStorageClass(self, storageClassName: str) -> StorageClass:
748 """Get a StorageClass instance associated with the supplied name.
750 Parameters
751 ----------
752 storageClassName : `str`
753 Name of the storage class to retrieve.
755 Returns
756 -------
757 instance : `StorageClass`
758 Instance of the correct `StorageClass`.
760 Raises
761 ------
762 KeyError
763 The requested storage class name is not registered.
764 """
765 return self._storageClasses[storageClassName]
767 def registerStorageClass(self, storageClass: StorageClass) -> None:
768 """Store the `StorageClass` in the factory.
770 Will be indexed by `StorageClass.name` and will return instances
771 of the supplied `StorageClass`.
773 Parameters
774 ----------
775 storageClass : `StorageClass`
776 Type of the Python `StorageClass` to register.
778 Raises
779 ------
780 ValueError
781 If a storage class has already been registered with
782 storageClassName and the previous definition differs.
783 """
784 if storageClass.name in self._storageClasses: 784 ↛ 785line 784 didn't jump to line 785, because the condition on line 784 was never true
785 existing = self.getStorageClass(storageClass.name)
786 if existing != storageClass:
787 raise ValueError(
788 f"New definition for StorageClass {storageClass.name} ({storageClass}) "
789 f"differs from current definition ({existing})"
790 )
791 else:
792 self._storageClasses[storageClass.name] = storageClass
794 def _unregisterStorageClass(self, storageClassName: str) -> None:
795 """Remove the named StorageClass from the factory.
797 Parameters
798 ----------
799 storageClassName : `str`
800 Name of storage class to remove.
802 Raises
803 ------
804 KeyError
805 The named storage class is not registered.
807 Notes
808 -----
809 This method is intended to simplify testing of StorageClassFactory
810 functionality and it is not expected to be required for normal usage.
811 """
812 del self._storageClasses[storageClassName]