Add recreate functional test for regression bug 1689692

When paging through instances, if the marker is found in cell0
and there are more instances under the limit, we continue paging
through the cell(s) to fill the limit. However, since the marker
was found in cell0 it's not going to be in any other cell database
so we'll end up failing with a marker not found error.

This change adds a functional recreate test for the bug.

The fix will build on this to show when the bug is fixed and the
test will be changed to assert expected normal behavior.

Change-Id: I234e0425e7e800b32cea78f5c1d99997bc03343f
Partial-Bug: #1689692
(cherry picked from commit fe0cf0fe047f9e8890170a90c48594d90e73bda5)

diff --git a/nova/tests/functional/regressions/test_bug_1689692.py b/nova/tests/functional/regressions/test_bug_1689692.py
new file mode 100644 (file)
index 0000000..b349ddb
--- /dev/null
+++ b/nova/tests/functional/regressions/test_bug_1689692.py
@@ -0,0 +1,91 @@
+# Copyright 2017 Huawei Technologies Co.,LTD.
+#
+# 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 nova import test
+from nova.tests import fixtures as nova_fixtures
+from nova.tests.functional.api import client as api_client
+from nova.tests.functional import integrated_helpers
+from nova.tests.unit import cast_as_call
+from nova.tests.unit.image import fake as image_fake
+from nova.tests.unit import policy_fixture
+
+
+class ServerListLimitMarkerCell0Test(test.TestCase,
+                                     integrated_helpers.InstanceHelperMixin):
+    """Regression test for bug 1689692 introduced in Ocata.
+
+    The user specifies a limit which is greater than the number of instances
+    left in the page and the marker starts in the cell0 database. What happens
+    is we don't null out the marker but we still have more limit so we continue
+    to page in the cell database(s) but the marker isn't found in any of those,
+    since it's already found in cell0, so it eventually raises a MarkerNotFound
+    error.
+    """
+
+    def setUp(self):
+        super(ServerListLimitMarkerCell0Test, self).setUp()
+        self.useFixture(policy_fixture.RealPolicyFixture())
+        # The NeutronFixture is needed to stub out validate_networks in API.
+        self.useFixture(nova_fixtures.NeutronFixture(self))
+        api_fixture = self.useFixture(nova_fixtures.OSAPIFixture(
+            api_version='v2.1'))
+        self.api = api_fixture.api
+
+        # the image fake backend needed for image discovery
+        image_fake.stub_out_image_service(self)
+        self.addCleanup(image_fake.FakeImageService_reset)
+        # We have to get the image before we use 2.latest otherwise we'll get
+        # a 404 on the /images proxy API because of 2.36.
+        self.image_id = self.api.get_images()[0]['id']
+        # Use the latest microversion available to make sure something does
+        # not regress in new microversions; cap as necessary.
+        self.api.microversion = 'latest'
+
+        self.start_service('conductor')
+        self.flags(driver='chance_scheduler', group='scheduler')
+        self.start_service('scheduler')
+        # We don't start the compute service because we want NoValidHost so
+        # all of the instances go into ERROR state and get put into cell0.
+        self.useFixture(cast_as_call.CastAsCall(self.stubs))
+
+    def test_list_servers_marker_in_cell0_more_limit(self):
+        """Creates three servers, then lists them with a marker on the first
+        and a limit of 3 which is more than what's left to page on (2) but
+        it shouldn't fail, it should just give the other two back. But due
+        to the bug we'll get a 400 since the marker isn't in cell1.
+        """
+        # create three test servers
+        for x in range(3):
+            server = self.api.post_server(
+                dict(server=self._build_minimal_create_server_request(
+                    self.api, 'test-list-server-limit%i' % x, self.image_id,
+                    networks='none')))
+            self.addCleanup(self.api.delete_server, server['id'])
+            self._wait_for_state_change(self.api, server, 'ERROR')
+
+        servers = self.api.get_servers()
+        self.assertEqual(3, len(servers))
+
+        # Take the first server and user that as our marker.
+        marker = servers[0]['id']
+        # Since we're paging after the first server as our marker, there are
+        # only two left so specifying three should just return two. However,
+        # due to the bug, we're going to get a MarkerNotFound error when trying
+        # to page to the cell1 database and the marker isn't there. Assert
+        # we get two servers back once the bug is fixed.
+        ex = self.assertRaises(api_client.OpenStackApiException,
+                               self.api.get_servers,
+                               search_opts=dict(marker=marker, limit=3))
+        self.assertEqual(400, ex.response.status_code)
+        self.assertIn('marker [%s] not found' % marker, ex.message)