Make it possible to use enginefacade decorators with class methods

The decorator form can now be used with bound methods after a fix
for the related bug was merged. Mention this in docs and release
notes, so that people are aware of it.

A new test is added to make sure this also works with class methods
(as well as to check that the proposed decorator applying order
is actually correct).

Related-Bug: #1520195

Change-Id: Ifea08114d6d89de9d67fcae397eb94c0afc4d339

1 files changed, 15 insertions, 0 deletions

diff --git a/oslo_db/tests/sqlalchemy/test_enginefacade.py b/oslo_db/tests/sqlalchemy/test_enginefacade.py
index 7f77c28..d27f7bf 100644
--- a/oslo_db/tests/sqlalchemy/test_enginefacade.py
+++ b/oslo_db/tests/sqlalchemy/test_enginefacade.py
@@ -1017,6 +1017,21 @@ class MockFacadeTest(oslo_test_base.BaseTestCase):
                 with self._assert_reader_session(makers) as session:
                     session.execute("test")
 
+    def test_context_found_for_class_method(self):
+        context = oslo_context.RequestContext()
+
+        class Spam(object):
+            @classmethod
+            @enginefacade.reader
+            def go(cls, context):
+                context.session.execute("test")
+        Spam.go(context)
+
+        with self._assert_engines() as engines:
+            with self._assert_makers(engines) as makers:
+                with self._assert_reader_session(makers) as session:
+                    session.execute("test")
+
 
 class SynchronousReaderWSlaveMockFacadeTest(MockFacadeTest):
     synchronous_reader = True