diff options
Diffstat (limited to 'lib/sqlalchemy/orm/interfaces.py')
| -rw-r--r-- | lib/sqlalchemy/orm/interfaces.py | 62 |
1 files changed, 49 insertions, 13 deletions
diff --git a/lib/sqlalchemy/orm/interfaces.py b/lib/sqlalchemy/orm/interfaces.py index ad2452c1b..299ccaaaf 100644 --- a/lib/sqlalchemy/orm/interfaces.py +++ b/lib/sqlalchemy/orm/interfaces.py @@ -24,7 +24,8 @@ from .. import util from ..sql import operators from .base import (ONETOMANY, MANYTOONE, MANYTOMANY, EXT_CONTINUE, EXT_STOP, NOT_EXTENSION) -from .base import InspectionAttr, _MappedAttribute +from .base import (InspectionAttr, InspectionAttr, + InspectionAttrInfo, _MappedAttribute) import collections # imported later @@ -48,11 +49,8 @@ __all__ = ( ) -class MapperProperty(_MappedAttribute, InspectionAttr): - """Manage the relationship of a ``Mapper`` to a single class - attribute, as well as that attribute as it appears on individual - instances of the class, including attribute instrumentation, - attribute access, loading behavior, and dependency calculations. +class MapperProperty(_MappedAttribute, InspectionAttr, util.MemoizedSlots): + """Represent a particular class attribute mapped by :class:`.Mapper`. The most common occurrences of :class:`.MapperProperty` are the mapped :class:`.Column`, which is represented in a mapping as @@ -63,6 +61,11 @@ class MapperProperty(_MappedAttribute, InspectionAttr): """ + __slots__ = ( + '_configure_started', '_configure_finished', 'parent', 'key', + 'info' + ) + cascade = frozenset() """The set of 'cascade' attribute names. @@ -78,6 +81,32 @@ class MapperProperty(_MappedAttribute, InspectionAttr): """ + def _memoized_attr_info(self): + """Info dictionary associated with the object, allowing user-defined + data to be associated with this :class:`.InspectionAttr`. + + The dictionary is generated when first accessed. Alternatively, + it can be specified as a constructor argument to the + :func:`.column_property`, :func:`.relationship`, or :func:`.composite` + functions. + + .. versionadded:: 0.8 Added support for .info to all + :class:`.MapperProperty` subclasses. + + .. versionchanged:: 1.0.0 :attr:`.MapperProperty.info` is also + available on extension types via the + :attr:`.InspectionAttrInfo.info` attribute, so that it can apply + to a wider variety of ORM and extension constructs. + + .. seealso:: + + :attr:`.QueryableAttribute.info` + + :attr:`.SchemaItem.info` + + """ + return {} + def setup(self, context, entity, path, adapter, **kwargs): """Called by Query for the purposes of constructing a SQL statement. @@ -139,8 +168,9 @@ class MapperProperty(_MappedAttribute, InspectionAttr): """ - _configure_started = False - _configure_finished = False + def __init__(self): + self._configure_started = False + self._configure_finished = False def init(self): """Called after all mappers are created to assemble @@ -303,6 +333,8 @@ class PropComparator(operators.ColumnOperators): """ + __slots__ = 'prop', 'property', '_parentmapper', '_adapt_to_entity' + def __init__(self, prop, parentmapper, adapt_to_entity=None): self.prop = self.property = prop self._parentmapper = parentmapper @@ -331,7 +363,7 @@ class PropComparator(operators.ColumnOperators): else: return self._adapt_to_entity._adapt_element - @util.memoized_property + @property def info(self): return self.property.info @@ -420,6 +452,8 @@ class StrategizedProperty(MapperProperty): """ + __slots__ = '_strategies', 'strategy' + strategy_wildcard_key = None def _get_context_loader(self, context, path): @@ -483,14 +517,14 @@ class StrategizedProperty(MapperProperty): not mapper.class_manager._attr_has_impl(self.key): self.strategy.init_class_attribute(mapper) - _strategies = collections.defaultdict(dict) + _all_strategies = collections.defaultdict(dict) @classmethod def strategy_for(cls, **kw): def decorate(dec_cls): dec_cls._strategy_keys = [] key = tuple(sorted(kw.items())) - cls._strategies[cls][key] = dec_cls + cls._all_strategies[cls][key] = dec_cls dec_cls._strategy_keys.append(key) return dec_cls return decorate @@ -498,8 +532,8 @@ class StrategizedProperty(MapperProperty): @classmethod def _strategy_lookup(cls, *key): for prop_cls in cls.__mro__: - if prop_cls in cls._strategies: - strategies = cls._strategies[prop_cls] + if prop_cls in cls._all_strategies: + strategies = cls._all_strategies[prop_cls] try: return strategies[key] except KeyError: @@ -558,6 +592,8 @@ class LoaderStrategy(object): """ + __slots__ = 'parent_property', 'is_class_level', 'parent', 'key' + def __init__(self, parent): self.parent_property = parent self.is_class_level = False |