openstack/deb-python-sqlalchemy-utils
Code Issues Proposed changes

Fix sort_query support for queries using mappers

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This commit is contained in:
Konsta Vesterinen
2014-08-28 23:03:27 +03:00
parent 0340ea1533
commit 01b58b5599
4 changed files with 107 additions and 81 deletions
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99
sqlalchemy_utils/functions/orm.py
View File

@@ -12,6 +12,7 @@ from sqlalchemy.ext.hybrid import hybrid_property
from sqlalchemy.orm import mapperlib
from sqlalchemy.orm.attributes import InstrumentedAttribute
from sqlalchemy.orm.exc import UnmappedInstanceError
from sqlalchemy.orm.properties import ColumnProperty
from sqlalchemy.orm.query import _ColumnEntity
from sqlalchemy.orm.session import object_session
from sqlalchemy.orm.util import AliasedInsp
@@ -197,13 +198,7 @@ def get_tables(mixed):
SQLAlchemy Mapper / Declarative class or a SA Alias object wrapping
any of these objects.
"""
if isinstance(mixed, sa.orm.util.AliasedClass):
mapper = sa.inspect(mixed).mapper
else:
if not isclass(mixed):
mixed = mixed.__class__
mapper = sa.inspect(mixed)
return mapper.tables
return get_mapper(mixed).tables
def get_columns(mixed):
@@ -414,17 +409,19 @@ def get_query_entities(query):
:param query: SQLAlchemy Query object
"""
return list(
map(get_selectable, chain(query._entities, query._join_entities))
)
return [
get_query_entity(entity) for entity in
chain(query._entities, query._join_entities)
]
def get_selectable(mixed):
if isinstance(mixed, (sa.orm.Mapper, AliasedInsp)):
return mixed
expr = mixed.expr
def get_query_entity(mixed):
if hasattr(mixed, 'expr'):
expr = mixed.expr
else:
expr = mixed
if isinstance(expr, sa.orm.attributes.InstrumentedAttribute):
return expr.parent
return expr.parent.class_
elif isinstance(expr, sa.Column):
return expr.table
elif isinstance(expr, sa.sql.expression.Label):
@@ -432,17 +429,22 @@ def get_selectable(mixed):
return mixed.entity_zero
else:
return expr
elif isinstance(expr, sa.orm.Mapper):
return expr.class_
elif isinstance(expr, AliasedInsp):
return expr.entity
return expr
def get_query_entity_by_alias(query, alias):
entities = get_query_entities(query)
if not alias:
return entities[0]
for entity in entities:
if isinstance(entity, AliasedInsp):
name = entity.name
if isinstance(entity, sa.orm.util.AliasedClass):
name = sa.inspect(entity).name
else:
name = get_mapper(entity).tables[0].name
@@ -457,17 +459,61 @@ def get_polymorphic_mappers(mixed):
return mixed.polymorphic_map.values()
def get_attrs(expr):
insp = sa.inspect(expr)
mapper = get_mapper(expr)
polymorphic_mappers = get_polymorphic_mappers(insp)
def get_query_descriptor(query, entity, attr):
if attr in query_labels(query):
return attr
else:
entity = get_query_entity_by_alias(query, entity)
if entity:
descriptor = get_descriptor(entity, attr)
if (
hasattr(descriptor, 'property') and
isinstance(descriptor.property, sa.orm.RelationshipProperty)
):
return
return descriptor
def get_descriptor(entity, attr):
mapper = sa.inspect(entity)
for key, descriptor in get_all_descriptors(mapper).items():
if attr == key:
prop = (
descriptor.property
if hasattr(descriptor, 'property')
else None
)
if isinstance(prop, ColumnProperty):
if isinstance(entity, sa.orm.util.AliasedClass):
for c in mapper.selectable.c:
if c.key == attr:
return c
else:
# If the property belongs to a class that uses
# polymorphic inheritance we have to take into account
# situations where the attribute exists in child class
# but not in parent class.
return getattr(prop.parent.class_, attr)
else:
# Handle synonyms, relationship proeprties and hybrid
# properties
try:
return getattr(entity, attr)
except AttributeError:
pass
def get_all_descriptors(expr):
insp = sa.inspect(expr)
polymorphic_mappers = get_polymorphic_mappers(insp)
if polymorphic_mappers:
attrs = {}
for submapper in polymorphic_mappers:
attrs.update(submapper.attrs)
attrs.update(submapper.all_orm_descriptors)
return attrs
return mapper.attrs
return get_mapper(expr).all_orm_descriptors
def get_hybrid_properties(model):
@@ -521,13 +567,6 @@ def get_hybrid_properties(model):
)
def get_expr_attr(expr, prop):
if isinstance(expr, AliasedInsp):
return getattr(expr.selectable.c, prop.key)
else:
return getattr(prop.parent.class_, prop.key)
def get_declarative_base(model):
"""
Returns the declarative base for given model class.

48
sqlalchemy_utils/functions/sort_query.py
View File

@@ -1,15 +1,5 @@
import sqlalchemy as sa
from sqlalchemy.orm.properties import ColumnProperty, SynonymProperty
from sqlalchemy.sql.expression import desc, asc, Label
from sqlalchemy.orm.util import AliasedInsp
from .orm import (
get_attrs,
get_expr_attr,
get_hybrid_properties,
get_query_entity_by_alias,
get_query_entities,
query_labels,
)
from sqlalchemy.sql.expression import desc, asc
from .orm import get_query_descriptor
class QuerySorterException(Exception):
@@ -18,18 +8,11 @@ class QuerySorterException(Exception):
class QuerySorter(object):
def __init__(self, silent=True, separator='-'):
self.labels = []
self.separator = separator
self.silent = silent
def assign_order_by(self, entity, attr, func):
expr = None
if attr in self.labels:
expr = attr
else:
entity = get_query_entity_by_alias(self.query, entity)
if entity:
expr = self.order_by_attr(entity, attr)
expr = get_query_descriptor(self.query, entity, attr)
if expr is not None:
return self.query.order_by(func(expr))
@@ -39,30 +22,6 @@ class QuerySorter(object):
)
return self.query
def order_by_attr(self, entity, attr):
properties = get_attrs(entity)
if attr in properties:
property_ = properties[attr]
if isinstance(property_, ColumnProperty):
if isinstance(property_.columns[0], Label):
return getattr(entity, property_.key)
else:
return get_expr_attr(entity, property_)
elif isinstance(property_, SynonymProperty):
return get_expr_attr(entity, property_)
return
mapper = sa.inspect(entity)
entity = mapper.entity
if isinstance(mapper, AliasedInsp):
mapper = mapper.mapper
for key in get_hybrid_properties(mapper).keys():
if attr == key:
return getattr(entity, attr)
def parse_sort_arg(self, arg):
if arg[0] == self.separator:
func = desc
@@ -79,7 +38,6 @@ class QuerySorter(object):
def __call__(self, query, *args):
self.query = query
self.labels = query_labels(query)
for sort in args:
if not sort:

10
tests/functions/test_get_query_entities.py
View File

@@ -41,7 +41,7 @@ class TestGetQueryEntities(TestCase):
def test_mapper(self):
query = self.session.query(sa.inspect(self.TextItem))
assert list(get_query_entities(query)) == [sa.inspect(self.TextItem)]
assert list(get_query_entities(query)) == [self.TextItem]
def test_entity(self):
query = self.session.query(self.TextItem)
@@ -49,7 +49,7 @@ class TestGetQueryEntities(TestCase):
def test_instrumented_attribute(self):
query = self.session.query(self.TextItem.id)
assert list(get_query_entities(query)) == [sa.inspect(self.TextItem)]
assert list(get_query_entities(query)) == [self.TextItem]
def test_column(self):
query = self.session.query(self.TextItem.__table__.c.id)
@@ -65,7 +65,7 @@ class TestGetQueryEntities(TestCase):
self.BlogPost, self.BlogPost.id == self.TextItem.id
)
assert list(get_query_entities(query)) == [
self.TextItem, sa.inspect(self.BlogPost)
self.TextItem, self.BlogPost
]
def test_joined_aliased_entity(self):
@@ -74,9 +74,7 @@ class TestGetQueryEntities(TestCase):
query = self.session.query(self.TextItem).join(
alias, alias.id == self.TextItem.id
)
assert list(get_query_entities(query)) == [
self.TextItem, sa.inspect(alias)
]
assert list(get_query_entities(query)) == [self.TextItem, alias]
def test_column_entity_with_label(self):
query = self.session.query(self.Article.id.label('id'))

31
tests/test_sort_query.py
View File

@@ -156,6 +156,37 @@ class TestSortQuery(TestCase):
query = sort_query(query, 'some_hybrid')
assert_contains('ORDER BY article.name ASC', query)
def test_with_mapper_and_column_property(self):
class Apple(self.Base):
__tablename__ = 'apple'
id = sa.Column(sa.Integer, primary_key=True)
article_id = sa.Column(sa.Integer, sa.ForeignKey(self.Article.id))
self.Article.apples = sa.orm.relationship(Apple)
self.Article.apple_count = sa.orm.column_property(
sa.select([sa.func.count(Apple.id)])
.where(Apple.article_id == self.Article.id)
.correlate(self.Article.__table__)
.label('apple_count'),
deferred=True
)
query = (
self.session.query(sa.inspect(self.Article))
.outerjoin(self.Article.apples)
.options(
sa.orm.undefer(self.Article.apple_count)
)
.options(sa.orm.contains_eager(self.Article.apples))
)
query = sort_query(query, 'apple_count')
assert 'ORDER BY apple_count' in str(query)
def test_table(self):
query = self.session.query(self.Article.__table__)
query = sort_query(query, 'name')
assert_contains('ORDER BY name', query)
class TestSortQueryRelationshipCounts(TestCase):
"""