modernize some more examples

10 files changed, 80 insertions, 71 deletions

diff --git a/examples/association/dict_of_sets_with_default.py b/examples/association/dict_of_sets_with_default.py
index 63c0f4531..9a43e300c 100644
--- a/examples/association/dict_of_sets_with_default.py
+++ b/examples/association/dict_of_sets_with_default.py
@@ -69,7 +69,7 @@ if __name__ == '__main__':
 
     session.add_all([
         A(collections={
-            "1":set([1, 2, 3]),
+            "1": set([1, 2, 3]),
         })
     ])
     session.commit()
diff --git a/examples/association/proxied_association.py b/examples/association/proxied_association.py
index 96e9e6b07..7f4d611a7 100644
--- a/examples/association/proxied_association.py
+++ b/examples/association/proxied_association.py
@@ -96,6 +96,6 @@ if __name__ == '__main__':
     # print customers who bought 'MySQL Crowbar' on sale
     orders = session.query(Order).\
                     join('order_items', 'item').\
-                    filter(Item.description=='MySQL Crowbar').\
+                    filter(Item.description == 'MySQL Crowbar').\
                     filter(Item.price > OrderItem.price)
-    print [order.customer_name for order in orders]
+    print [o.customer_name for o in orders]
diff --git a/examples/custom_attributes/custom_management.py b/examples/custom_attributes/custom_management.py
index 12b745db6..2199e0138 100644
--- a/examples/custom_attributes/custom_management.py
+++ b/examples/custom_attributes/custom_management.py
@@ -64,7 +64,8 @@ class MyClass(object):
 
 
 if __name__ == '__main__':
-    meta = MetaData(create_engine('sqlite://'))
+    engine = create_engine('sqlite://')
+    meta = MetaData()
 
     table1 = Table('table1', meta,
                     Column('id', Integer, primary_key=True),
@@ -73,7 +74,7 @@ if __name__ == '__main__':
                     Column('id', Integer, primary_key=True),
                     Column('name', Text),
                     Column('t1id', Integer, ForeignKey('table1.id')))
-    meta.create_all()
+    meta.create_all(engine)
 
     class A(MyClass):
         pass
@@ -82,7 +83,7 @@ if __name__ == '__main__':
         pass
 
     mapper(A, table1, properties={
-        'bs':relationship(B)
+        'bs': relationship(B)
     })
 
     mapper(B, table2)
@@ -92,7 +93,7 @@ if __name__ == '__main__':
     assert a1.name == 'a1'
     assert a1.bs[0].name == 'b1'
 
-    sess = Session()
+    sess = Session(engine)
     sess.add(a1)
 
     sess.commit()
diff --git a/examples/custom_attributes/listen_for_events.py b/examples/custom_attributes/listen_for_events.py
index 80a33c0d8..4cdf4b056 100644
--- a/examples/custom_attributes/listen_for_events.py
+++ b/examples/custom_attributes/listen_for_events.py
@@ -4,7 +4,7 @@ and listen for change events.
 
 """
 
-from sqlalchemy import event, orm
+from sqlalchemy import event
 
 def configure_listener(class_, key, inst):
     def append(instance, value, initiator):
diff --git a/examples/dynamic_dict/dynamic_dict.py b/examples/dynamic_dict/dynamic_dict.py
index 725d65619..ec7c8e918 100644
--- a/examples/dynamic_dict/dynamic_dict.py
+++ b/examples/dynamic_dict/dynamic_dict.py
@@ -32,14 +32,15 @@ from sqlalchemy.ext.declarative import declarative_base
 from sqlalchemy import create_engine, Column, Integer, String, ForeignKey

 from sqlalchemy.orm import sessionmaker, relationship

 

-engine=create_engine('sqlite://', echo=True)

+engine = create_engine('sqlite://', echo=True)

 Base = declarative_base(engine)

 

 class Parent(Base):

     __tablename__ = 'parent'

     id = Column(Integer, primary_key=True)

     name = Column(String(50))

-    _collection = relationship("Child", lazy="dynamic", cascade="all, delete-orphan")

+    _collection = relationship("Child", lazy="dynamic",

+                                    cascade="all, delete-orphan")

 

     @property

     def child_map(self):

diff --git a/examples/large_collection/large_collection.py b/examples/large_collection/large_collection.py
index b3aa5299d..3e386ae64 100644
--- a/examples/large_collection/large_collection.py
+++ b/examples/large_collection/large_collection.py
@@ -14,7 +14,8 @@ org_table = Table('organizations', meta,
 member_table = Table('members', meta,
     Column('member_id', Integer, primary_key=True),
     Column('member_name', String(50), nullable=False, key='name'),
-    Column('org_id', Integer, ForeignKey('organizations.org_id', ondelete="CASCADE")),
+    Column('org_id', Integer,
+                    ForeignKey('organizations.org_id', ondelete="CASCADE")),
     mysql_engine='InnoDB')
 
 
diff --git a/examples/nested_sets/nested_sets.py b/examples/nested_sets/nested_sets.py
index e35ea61c3..8225a09f2 100644
--- a/examples/nested_sets/nested_sets.py
+++ b/examples/nested_sets/nested_sets.py
@@ -6,47 +6,17 @@ http://www.intelligententerprise.com/001020/celko.jhtml
 
 from sqlalchemy import (create_engine, Column, Integer, String, select, case,
     func)
-from sqlalchemy.orm import sessionmaker, MapperExtension, aliased
+from sqlalchemy.orm import Session, aliased
 from sqlalchemy.ext.declarative import declarative_base
+from sqlalchemy import event
 
-engine = create_engine('sqlite://', echo=True)
 Base = declarative_base()
 
-class NestedSetExtension(MapperExtension):
-    def before_insert(self, mapper, connection, instance):
-        if not instance.parent:
-            instance.left = 1
-            instance.right = 2
-        else:
-            personnel = mapper.mapped_table
-            right_most_sibling = connection.scalar(
-                select([personnel.c.rgt]).where(personnel.c.emp==instance.parent.emp)
-            )
-
-            connection.execute(
-                personnel.update(personnel.c.rgt>=right_most_sibling).values(
-                    lft = case(
-                            [(personnel.c.lft>right_most_sibling, personnel.c.lft + 2)],
-                            else_ = personnel.c.lft
-                          ),
-                    rgt = case(
-                            [(personnel.c.rgt>=right_most_sibling, personnel.c.rgt + 2)],
-                            else_ = personnel.c.rgt
-                          )
-                )
-            )
-            instance.left = right_most_sibling
-            instance.right = right_most_sibling + 1
-
-    # before_update() would be needed to support moving of nodes
-    # after_delete() would be needed to support removal of nodes.
-    # [ticket:1172] needs to be implemented for deletion to work as well.
-
 class Employee(Base):
     __tablename__ = 'personnel'
     __mapper_args__ = {
-        'extension':NestedSetExtension(),
-        'batch':False  # allows extension to fire for each instance before going to the next.
+        'batch': False  # allows extension to fire for each
+                        # instance before going to the next.
     }
 
     parent = None
@@ -59,9 +29,44 @@ class Employee(Base):
     def __repr__(self):
         return "Employee(%s, %d, %d)" % (self.emp, self.left, self.right)
 
+@event.listens_for(Employee, "before_insert")
+def before_insert(mapper, connection, instance):
+    if not instance.parent:
+        instance.left = 1
+        instance.right = 2
+    else:
+        personnel = mapper.mapped_table
+        right_most_sibling = connection.scalar(
+            select([personnel.c.rgt]).
+                where(personnel.c.emp == instance.parent.emp)
+        )
+
+        connection.execute(
+            personnel.update(
+                personnel.c.rgt >= right_most_sibling).values(
+                    lft=case(
+                        [(personnel.c.lft > right_most_sibling,
+                            personnel.c.lft + 2)],
+                        else_=personnel.c.lft
+                    ),
+                    rgt=case(
+                        [(personnel.c.rgt >= right_most_sibling,
+                                personnel.c.rgt + 2)],
+                            else_=personnel.c.rgt
+                      )
+            )
+        )
+        instance.left = right_most_sibling
+        instance.right = right_most_sibling + 1
+
+    # before_update() would be needed to support moving of nodes
+    # after_delete() would be needed to support removal of nodes.
+
+engine = create_engine('sqlite://', echo=True)
+
 Base.metadata.create_all(engine)
 
-session = sessionmaker(bind=engine)()
+session = Session(bind=engine)
 
 albert = Employee(emp='Albert')
 bert = Employee(emp='Bert')
@@ -81,23 +86,26 @@ fred.parent = chuck
 session.add_all([albert, bert, chuck, donna, eddie, fred])
 session.commit()
 
-print session.query(Employee).all()
+print(session.query(Employee).all())
 
 # 1. Find an employee and all his/her supervisors, no matter how deep the tree.
 ealias = aliased(Employee)
-print session.query(Employee).\
+print(session.query(Employee).\
             filter(ealias.left.between(Employee.left, Employee.right)).\
-            filter(ealias.emp=='Eddie').all()
+            filter(ealias.emp == 'Eddie').all())
 
-#2. Find the employee and all his/her subordinates. (This query has a nice symmetry with the first query.)
-print session.query(Employee).\
+#2. Find the employee and all his/her subordinates.
+# (This query has a nice symmetry with the first query.)
+print(session.query(Employee).\
     filter(Employee.left.between(ealias.left, ealias.right)).\
-    filter(ealias.emp=='Chuck').all()
+    filter(ealias.emp == 'Chuck').all())
 
-#3. Find the level of each node, so you can print the tree as an indented listing.
-for indentation, employee in session.query(func.count(Employee.emp).label('indentation') - 1, ealias).\
+#3. Find the level of each node, so you can print the tree
+# as an indented listing.
+for indentation, employee in session.query(
+            func.count(Employee.emp).label('indentation') - 1, ealias).\
     filter(ealias.left.between(Employee.left, Employee.right)).\
     group_by(ealias.emp).\
-    order_by(ealias.left):
-    print "    " * indentation + str(employee)
+        order_by(ealias.left):
+    print("    " * indentation + str(employee))
 
diff --git a/examples/versioning/test_versioning.py b/examples/versioning/test_versioning.py
index 9781fdc5d..43e2b0ae1 100644
--- a/examples/versioning/test_versioning.py
+++ b/examples/versioning/test_versioning.py
@@ -5,6 +5,9 @@ from sqlalchemy import create_engine, Column, Integer, String, ForeignKey
 from sqlalchemy.orm import clear_mappers, sessionmaker, deferred, relationship
 from _lib import ComparableEntity, eq_
 
+engine = Session = None
+
+
 def setup():
     global engine
     engine = create_engine('sqlite://', echo=True)
@@ -12,16 +15,16 @@ def setup():
 class TestVersioning(TestCase):
     def setUp(self):
         global Base, Session, Versioned
-        Base = declarative_base(bind=engine)
-        Session = sessionmaker()
+        Base = declarative_base()
+        Session = sessionmaker(engine)
         versioned_session(Session)
 
     def tearDown(self):
         clear_mappers()
-        Base.metadata.drop_all()
+        Base.metadata.drop_all(engine)
 
     def create_tables(self):
-        Base.metadata.create_all()
+        Base.metadata.create_all(engine)
 
     def test_plain(self):
         class SomeClass(Versioned, Base, ComparableEntity):
diff --git a/examples/vertical/dictlike-polymorphic.py b/examples/vertical/dictlike-polymorphic.py
index c4eb6b5ce..f800eea73 100644
--- a/examples/vertical/dictlike-polymorphic.py
+++ b/examples/vertical/dictlike-polymorphic.py
@@ -254,6 +254,3 @@ if __name__ == '__main__':
     q = (session.query(AnimalFact).
          filter(with_characteristic(u'cuteness', u'very cute')))
     print q.all()
-
-    session.close()
-    metadata.drop_all(engine)
diff --git a/examples/vertical/dictlike.py b/examples/vertical/dictlike.py
index e288d70ba..71ab77342 100644
--- a/examples/vertical/dictlike.py
+++ b/examples/vertical/dictlike.py
@@ -124,7 +124,7 @@ class VerticalPropertyDictMixin(object):
 
 if __name__ == '__main__':
     from sqlalchemy import (MetaData, Table, Column, Integer, Unicode,
-        ForeignKey, UnicodeText, and_, not_)
+        ForeignKey, UnicodeText, and_, not_, create_engine)
     from sqlalchemy.orm import mapper, relationship, Session
     from sqlalchemy.orm.collections import attribute_mapped_collection
 
@@ -172,10 +172,9 @@ if __name__ == '__main__':
         })
     mapper(AnimalFact, facts)
 
-
-    metadata.bind = 'sqlite:///'
-    metadata.create_all()
-    session = Session()
+    engine = create_engine("sqlite://")
+    metadata.create_all(engine)
+    session = Session(bind=engine)
 
     stoat = Animal(u'stoat')
     stoat[u'color'] = u'reddish'
@@ -195,9 +194,9 @@ if __name__ == '__main__':
     critter[u'cuteness'] = u'very'
 
     print 'changing cuteness:'
-    metadata.bind.echo = True
+    engine.echo = True
     session.commit()
-    metadata.bind.echo = False
+    engine.echo = False
 
     marten = Animal(u'marten')
     marten[u'color'] = u'brown'
@@ -245,4 +244,3 @@ if __name__ == '__main__':
     print 'just the facts', q.all()
 
 
-    metadata.drop_all()