diff options
Diffstat (limited to 'lib/sqlalchemy/orm/loading.py')
| -rw-r--r-- | lib/sqlalchemy/orm/loading.py | 77 |
1 files changed, 42 insertions, 35 deletions
diff --git a/lib/sqlalchemy/orm/loading.py b/lib/sqlalchemy/orm/loading.py index 3d5aa4fb4..add2ae43b 100644 --- a/lib/sqlalchemy/orm/loading.py +++ b/lib/sqlalchemy/orm/loading.py @@ -43,7 +43,10 @@ def instances(query, cursor, context): def filter_fn(row): return tuple(fn(x) for x, fn in zip(row, filter_fns)) - if context.statement is not None: + if context._predefined_statement: + # if the Query didn't actually build the statement, + # we use the result set to determine where the columns + # we're looking for are located. context._setup_column_processors( [ (cursor._index_of(col), col) @@ -223,13 +226,14 @@ def load_on_ident(query, key, return None -def instance_processor(mapper, props_toload, context, column_collection, - query_entity, path, adapter, - only_load_props=None, refresh_state=None, - polymorphic_discriminator=None, - _polymorphic_from=None, - _polymorphic_pk_getters=None, - _polymorphic_from_populators=None): +def _instance_processor( + mapper, props_toload, context, column_collection, + query_entity, path, adapter, + only_load_props=None, refresh_state=None, + polymorphic_discriminator=None, + _polymorphic_from=None, + _polymorphic_pk_getters=None, + _polymorphic_from_populators=None): """Produce a mapper level row processor callable which processes rows into mapped instances.""" @@ -240,6 +244,13 @@ def instance_processor(mapper, props_toload, context, column_collection, # of populators that were already set up for us. populators = _polymorphic_from_populators + + for prop in props_toload: + prop.setup_for_missing_attribute( + context, query_entity, path, mapper, + _polymorphic_from_populators + ) + else: populators = collections.defaultdict(list) @@ -257,12 +268,13 @@ def instance_processor(mapper, props_toload, context, column_collection, context, query_entity, path, + mapper, adapter, - only_load_props=only_load_props, - column_collection=column_collection, + column_collection, populators=per_mapper_populators[prop.parent] - if load_is_polymorphic - else populators + if load_is_polymorphic and not mapper.isa(prop.parent) + else populators, + only_load_props=only_load_props, ) if _polymorphic_pk_getters: @@ -428,7 +440,8 @@ def instance_processor(mapper, props_toload, context, column_collection, # if we are doing polymorphic, dispatch to a different _instance() # method specific to the subclass mapper _instance = _decorate_polymorphic_switch( - _instance, context, mapper, per_mapper_populators, path, + _instance, context, mapper, props_toload, + per_mapper_populators, path, polymorphic_discriminator, adapter, pk_getters) return _instance @@ -516,7 +529,8 @@ def _validate_version_id(mapper, state, dict_, row, adapter): def _decorate_polymorphic_switch( - instance_fn, context, mapper, per_mapper_populators, path, + instance_fn, context, mapper, props_toload, + per_mapper_populators, path, polymorphic_discriminator, adapter, pk_getters): if polymorphic_discriminator is not None: @@ -535,6 +549,8 @@ def _decorate_polymorphic_switch( context.column_processors.append( (polymorphic_on, polymorphic_getter.setup)) + props_setup = set(props_toload) + def configure_subclass_mapper(discriminator): try: sub_mapper = mapper.polymorphic_map[discriminator] @@ -554,27 +570,18 @@ def _decorate_polymorphic_switch( if super_mapper is mapper: break - # TODO! - # big problems: - # 1. "quick" is being multiply populated with redundant - # populators - # 2. columns like "golf_swing", which are not rendered in - # setup(), therefore have no populator at all, we normally - # are expecting an "expire" populator to set up for a deferred - # load. We need to either make it so these populators aren't - # needed or - # that we in here do actually add more non-column populators, - # which may mean that we need some version of - # row_processor() again for this case. It would be - # along the lines of missing_attribute_populator() and would be - # specific to those cases where we have to produce a subclass - # against a query that did not specify this class in its - # entities. - # if discriminator == 'boss': - # import pdb - # pdb.set_trace() - return instance_processor( - sub_mapper, None, context, None, None, + keys_setup = set(p.key for p in props_setup) + + props_needed = set( + prop for prop in sub_mapper._props.values() + ).difference(props_setup) + + props_needed = props_needed.difference( + p for p in props_needed if p.key in keys_setup + ) + + return _instance_processor( + sub_mapper, props_needed, context, None, None, path, adapter, _polymorphic_from=mapper, _polymorphic_pk_getters=pk_getters, _polymorphic_from_populators=populators) |