From: Mike Bayer <mike_mp@zzzcomputing.com>
Date: Sat, 13 Dec 2014 00:59:11 +0000 (-0500)
Subject: - Added new method :meth:`.Session.invalidate`, functions similarly
X-Git-Tag: rel_0_9_9~62
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=c7de21b92cc072750607eef88f729f8cc20a6fb0;p=thirdparty%2Fsqlalchemy%2Fsqlalchemy.git

- Added new method :meth:`.Session.invalidate`, functions similarly
to :meth:`.Session.close`, except also calls
:meth:`.Connection.invalidate`
on all connections, guaranteeing that they will not be returned to
the connection pool.  This is useful in situations e.g. dealing
with gevent timeouts when it is not safe to use the connection further,
even for rollbacks.
references #3258

(cherry picked from commit cf7981f60d485f17465f44c6ff651ae283ade377)
---

diff --git a/doc/build/changelog/changelog_09.rst b/doc/build/changelog/changelog_09.rst
index f10d482730..4198279594 100644
--- a/doc/build/changelog/changelog_09.rst
+++ b/doc/build/changelog/changelog_09.rst
@@ -13,6 +13,18 @@
 .. changelog::
     :version: 0.9.9
 
+    .. change::
+        :tags: enhancement, orm
+        :versions: 1.0.0
+
+        Added new method :meth:`.Session.invalidate`, functions similarly
+        to :meth:`.Session.close`, except also calls
+        :meth:`.Connection.invalidate`
+        on all connections, guaranteeing that they will not be returned to
+        the connection pool.  This is useful in situations e.g. dealing
+        with gevent timeouts when it is not safe to use the connection further,
+        even for rollbacks.
+
     .. change::
         :tags: bug, examples
         :versions: 1.0.0
diff --git a/lib/sqlalchemy/orm/session.py b/lib/sqlalchemy/orm/session.py
index f5c52a6ada..37f4ad5abe 100644
--- a/lib/sqlalchemy/orm/session.py
+++ b/lib/sqlalchemy/orm/session.py
@@ -435,11 +435,13 @@ class SessionTransaction(object):
 
         self.session.dispatch.after_rollback(self.session)
 
-    def close(self):
+    def close(self, invalidate=False):
         self.session.transaction = self._parent
         if self._parent is None:
             for connection, transaction, autoclose in \
                     set(self._connections.values()):
+                if invalidate:
+                    connection.invalidate()
                 if autoclose:
                     connection.close()
                 else:
@@ -1006,10 +1008,46 @@ class Session(_SessionClassMethods):
         not use any connection resources until they are first needed.
 
         """
+        self._close_impl(invalidate=False)
+
+    def invalidate(self):
+        """Close this Session, using connection invalidation.
+
+        This is a variant of :meth:`.Session.close` that will additionally
+        ensure that the :meth:`.Connection.invalidate` method will be called
+        on all :class:`.Connection` objects.  This can be called when
+        the database is known to be in a state where the connections are
+        no longer safe to be used.
+
+        E.g.::
+
+            try:
+                sess = Session()
+                sess.add(User())
+                sess.commit()
+            except gevent.Timeout:
+                sess.invalidate()
+                raise
+            except:
+                sess.rollback()
+                raise
+
+        This clears all items and ends any transaction in progress.
+
+        If this session were created with ``autocommit=False``, a new
+        transaction is immediately begun.  Note that this new transaction does
+        not use any connection resources until they are first needed.
+
+        .. versionadded:: 0.9.9
+
+        """
+        self._close_impl(invalidate=True)
+
+    def _close_impl(self, invalidate):
         self.expunge_all()
         if self.transaction is not None:
             for transaction in self.transaction._iterate_parents():
-                transaction.close()
+                transaction.close(invalidate)
 
     def expunge_all(self):
         """Remove all object instances from this ``Session``.
diff --git a/test/orm/test_session.py b/test/orm/test_session.py
index 186b7a781a..4057051ae8 100644
--- a/test/orm/test_session.py
+++ b/test/orm/test_session.py
@@ -1503,6 +1503,9 @@ class DisposedStates(fixtures.MappedTest):
     def test_close(self):
         self._test_session().close()
 
+    def test_invalidate(self):
+        self._test_session().invalidate()
+
     def test_expunge_all(self):
         self._test_session().expunge_all()
 
diff --git a/test/orm/test_transaction.py b/test/orm/test_transaction.py
index ba31e4c7d2..1d7e8e6936 100644
--- a/test/orm/test_transaction.py
+++ b/test/orm/test_transaction.py
@@ -184,6 +184,23 @@ class SessionTransactionTest(FixtureTest):
         assert users.count().scalar() == 1
         assert addresses.count().scalar() == 1
 
+    @testing.requires.independent_connections
+    def test_invalidate(self):
+        User, users = self.classes.User, self.tables.users
+        mapper(User, users)
+        sess = Session()
+        u = User(name='u1')
+        sess.add(u)
+        sess.flush()
+        c1 = sess.connection(User)
+
+        sess.invalidate()
+        assert c1.invalidated
+
+        eq_(sess.query(User).all(), [])
+        c2 = sess.connection(User)
+        assert not c2.invalidated
+
     def test_subtransaction_on_noautocommit(self):
         User, users = self.classes.User, self.tables.users