From fc2d39034b7ed3a5afbb6467302ae1cd431d57ad Mon Sep 17 00:00:00 2001
From: Doug Hellmann <doug@doughellmann.com>
Date: Wed, 19 Nov 2014 11:58:20 -0500
Subject: [PATCH] Add ClearRequestContext fixture

Add a fixture class for use in tests to provide a way to flush the
cached RequestContext without exposing how that is stored.

bp/graduate-oslo-context

Change-Id: I27dd50a61d364e1698823629e2676c10ced50af3
---
 doc/source/api/autoindex.rst            |  1 +
 doc/source/api/oslo_context.fixture.rst |  7 ++++++
 oslo_context/fixture.py                 | 30 +++++++++++++++++++++++++
 oslo_context/tests/test_context.py      | 11 ++-------
 oslo_context/tests/test_fixture.py      | 30 +++++++++++++++++++++++++
 5 files changed, 70 insertions(+), 9 deletions(-)
 create mode 100644 doc/source/api/oslo_context.fixture.rst
 create mode 100644 oslo_context/fixture.py
 create mode 100644 oslo_context/tests/test_fixture.py

diff --git a/doc/source/api/autoindex.rst b/doc/source/api/autoindex.rst
index eaaf790..1d5d077 100644
--- a/doc/source/api/autoindex.rst
+++ b/doc/source/api/autoindex.rst
@@ -2,4 +2,5 @@
    :maxdepth: 1
 
    oslo_context.context.rst
+   oslo_context.fixture.rst
    oslo_context.tests.test_context.rst
diff --git a/doc/source/api/oslo_context.fixture.rst b/doc/source/api/oslo_context.fixture.rst
new file mode 100644
index 0000000..58ef47f
--- /dev/null
+++ b/doc/source/api/oslo_context.fixture.rst
@@ -0,0 +1,7 @@
+The :mod:`oslo_context.fixture` Module
+======================================
+
+.. automodule:: oslo_context.fixture
+  :members:
+  :undoc-members:
+  :show-inheritance:
diff --git a/oslo_context/fixture.py b/oslo_context/fixture.py
new file mode 100644
index 0000000..51822e8
--- /dev/null
+++ b/oslo_context/fixture.py
@@ -0,0 +1,30 @@
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+import fixtures
+
+from oslo_context import context
+
+
+class ClearRequestContext(fixtures.Fixture):
+    """Clears any cached RequestContext at the end of a test case."""
+
+    def setUp(self):
+        super(ClearRequestContext, self).setUp()
+        self.addCleanup(self._remove_cached_context)
+
+    def _remove_cached_context(self):
+        """Remove the thread-local context stored in the module."""
+        try:
+            del context._request_store.context
+        except AttributeError:
+            pass
diff --git a/oslo_context/tests/test_context.py b/oslo_context/tests/test_context.py
index 655895d..97e3ca1 100644
--- a/oslo_context/tests/test_context.py
+++ b/oslo_context/tests/test_context.py
@@ -16,20 +16,14 @@
 from oslotest import base as test_base
 
 from oslo_context import context
+from oslo_context import fixture
 
 
 class ContextTest(test_base.BaseTestCase):
 
     def setUp(self):
         super(ContextTest, self).setUp()
-        self.addCleanup(self._remove_cached_context)
-
-    def _remove_cached_context(self):
-        """Remove the thread-local context stored in the module."""
-        try:
-            del context._request_store.context
-        except AttributeError:
-            pass
+        self.useFixture(fixture.ClearRequestContext())
 
     def test_context(self):
         ctx = context.RequestContext()
@@ -57,7 +51,6 @@ class ContextTest(test_base.BaseTestCase):
 
     def test_store_current(self):
         # By default a new context is stored.
-        self._remove_cached_context()
         ctx = context.RequestContext()
         self.assertIs(context.get_current(), ctx)
 
diff --git a/oslo_context/tests/test_fixture.py b/oslo_context/tests/test_fixture.py
new file mode 100644
index 0000000..7a5b3cc
--- /dev/null
+++ b/oslo_context/tests/test_fixture.py
@@ -0,0 +1,30 @@
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+from oslotest import base as test_base
+
+from oslo_context import context
+from oslo_context import fixture
+
+
+class ClearRequestContextTest(test_base.BaseTestCase):
+
+    # def setUp(self):
+    #     super(ContextTest, self).setUp()
+    #     self.useFixture(fixture.ClearRequestContext())
+
+    def test_store_current(self):
+        # By default a new context is stored.
+        ctx = context.RequestContext()
+        self.assertIs(context.get_current(), ctx)
+        fixture.ClearRequestContext()._remove_cached_context()
+        self.assertIsNone(context.get_current())