From: Mike Bayer <mike_mp@zzzcomputing.com>
Date: Mon, 16 Jul 2007 21:01:23 +0000 (+0000)
Subject: fix to SessionTransaction so it holds onto a Connection properly
X-Git-Tag: rel_0_4_6~103
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=56fe7f8cb79cd5b90c43153e8636138d8e1d8e10;p=thirdparty%2Fsqlalchemy%2Fsqlalchemy.git

fix to SessionTransaction so it holds onto a Connection properly
---

diff --git a/CHANGES b/CHANGES
index 83df609f10..d777d45dfc 100644
--- a/CHANGES
+++ b/CHANGES
@@ -71,14 +71,25 @@
 
     - added undefer_group() MapperOption, sets a set of "deferred"
       columns joined by a "group" to load as "undeferred".
-
+      
+    - session enhancements/fixes:
+        - session can be bound to Connections
+    
+    - rewrite of the "deterministic alias name" logic to be part of the 
+    SQL layer, produces much simpler alias and label names more in the
+    style of Hibernate
+    
 - sql
-  - added context manager (with statement) support for transactions
-  - added support for two phase commit, works with mysql and postgres so far.
-  - added a subtransaction implementation that uses savepoints.
-  - added support for savepoints.
-  - DynamicMetaData has been renamed to ThreadLocalMetaData
-  - BoundMetaData has been removed- regular MetaData is equivalent
+  - transactions:
+    - added context manager (with statement) support for transactions
+    - added support for two phase commit, works with mysql and postgres so far.
+    - added a subtransaction implementation that uses savepoints.
+    - added support for savepoints.
+  - MetaData:
+    - DynamicMetaData has been renamed to ThreadLocalMetaData
+    - BoundMetaData has been removed- regular MetaData is equivalent
+  - "anonymous" alias and label names are now generated at SQL compilation
+    time in a completely deterministic fashion...no more random hex IDs
   - significant architectural overhaul to SQL elements (ClauseElement).  
     all elements share  a common "mutability" framework which allows a 
     consistent approach to in-place modifications of elements as well as 
diff --git a/lib/sqlalchemy/orm/session.py b/lib/sqlalchemy/orm/session.py
index a4e2287ded..d482286045 100644
--- a/lib/sqlalchemy/orm/session.py
+++ b/lib/sqlalchemy/orm/session.py
@@ -4,7 +4,7 @@
 # This module is part of SQLAlchemy and is released under
 # the MIT License: http://www.opensource.org/licenses/mit-license.php
 
-from sqlalchemy import util, exceptions, sql
+from sqlalchemy import util, exceptions, sql, engine
 from sqlalchemy.orm import unitofwork, query
 from sqlalchemy.orm.mapper import object_mapper as _object_mapper
 from sqlalchemy.orm.mapper import class_mapper as _class_mapper
@@ -30,8 +30,6 @@ class SessionTransaction(object):
     def connection(self, mapper_or_class, entity_name=None):
         if isinstance(mapper_or_class, type):
             mapper_or_class = _class_mapper(mapper_or_class, entity_name=entity_name)
-        if self.parent is not None:
-            return self.parent.connection(mapper_or_class)
         engine = self.session.get_bind(mapper_or_class)
         return self.get_or_add(engine)
 
@@ -39,28 +37,36 @@ class SessionTransaction(object):
         return SessionTransaction(self.session, self)
 
     def add(self, bind):
+        if self.parent is not None:
+            return self.parent.add(bind)
+            
         if self.connections.has_key(bind.engine):
             raise exceptions.InvalidRequestError("Session already has a Connection associated for the given Connection's Engine")
         return self.get_or_add(bind)
 
     def get_or_add(self, bind):
-        # we reference the 'engine' attribute on the given object, which in the case of
-        # Connection, ProxyEngine, Engine, whatever, should return the original
-        # "Engine" object that is handling the connection.
-        if self.connections.has_key(bind.engine):
-            return self.connections[bind.engine][0]
-        e = bind.engine
-        c = bind.contextual_connect()
-        if not self.connections.has_key(e):
-            self.connections[e] = (c, c.begin(), c is not bind)
-        return self.connections[e][0]
+        if self.parent is not None:
+            return self.parent.get_or_add(bind)
+            
+        if self.connections.has_key(bind):
+            return self.connections[bind][0]
+
+        if not isinstance(bind, engine.Connection):
+            e = bind
+            c = bind.contextual_connect()
+        else:
+            e = bind.engine
+            c = bind
+
+        self.connections[bind] = self.connections[e] = (c, c.begin(), c is not bind)
+        return self.connections[bind][0]
 
     def commit(self):
         if self.parent is not None:
             return
         if self.autoflush:
             self.session.flush()
-        for t in self.connections.values():
+        for t in util.Set(self.connections.values()):
             t[1].commit()
         self.close()
 
diff --git a/test/orm/session.py b/test/orm/session.py
index e67037b0af..9fa7e7f821 100644
--- a/test/orm/session.py
+++ b/test/orm/session.py
@@ -84,6 +84,21 @@ class SessionTest(AssertMixin):
         transaction.rollback()
         assert len(sess.query(User).select()) == 0
 
+    def test_bound_connection(self):
+        class User(object):pass
+        mapper(User, users)
+        c = testbase.db.connect()
+        sess = create_session(bind=c)
+        transaction = sess.create_transaction()
+        trans2 = sess.create_transaction()
+        u = User()
+        sess.save(u)
+        sess.flush()
+        assert transaction.get_or_add(testbase.db) is trans2.get_or_add(testbase.db) #is transaction.get_or_add(c) is trans2.get_or_add(c) is c
+        trans2.commit()
+        transaction.rollback()
+        assert len(sess.query(User).select()) == 0
+        
     def test_close_two(self):
         c = testbase.db.connect()
         try: