Fix test_secret_stores tests

There were five minor issues with the test_secret_stores tests:

1) There is a typo in some test cases. They are calling
   unset_peferred_secret_store instead of unset_p<r>eferred_secret_store

2) Set and unset preferred secret stores API calls in the
   SecretStoresClient expect 200 response status code when in fact they
   should expect 204 instead [1].

3) test_get_preferred_secret_store test expects to get preferred
   secret store when in fact none is set for the project.

4) skip_checks() function did not call super's skip_checks()

5) test_set_unset_preferred_secret_store test expects to get preferred
   secret store for a project when there is no preferred secret store
   set for it.

[1] https://docs.openstack.org/barbican/rocky/api/reference/store_backends.html#post-v1-secret-stores-secret-store-id-preferred

Change-Id: Ic211ea87006662c5a24aef3d1b78a5aa85b5e35b

barbican_tempest_plugin/services/key_manager/json/secret_stores_client.py

@@ -49,12 +49,10 @@ class SecretStoresClient(base.BarbicanTempestClient):
 
     def set_preferred_secret_store(self, secret_store_id):
         uri = '/v1/secret-stores/{}/preferred'.format(secret_store_id)
-        resp, body = self.post(uri)
+        resp, body = self.post(uri, None)
-        self.expected_success(200, resp.status)
+        self.expected_success(204, resp.status)
-        return json.loads(body.decode('UTF-8'))
 
     def unset_preferred_secret_store(self, secret_store_id):
         uri = '/v1/secret-stores/{}/preferred'.format(secret_store_id)
         resp, body = self.delete(uri)
-        self.expected_success(200, resp.status)
+        self.expected_success(204, resp.status)
-        return json.loads(body.decode('UTF-8'))

barbican_tempest_plugin/tests/rbac/v1/test_secret_stores.py

@@ -97,6 +97,7 @@ class ProjectMemberTests(base.BarbicanV1RbacBase, BarbicanV1RbacSecretStores):
         We need to set up the devstack plugin to use multiple backends
         so we can run these tests.
         """
+        super().skip_checks()
         if not CONF.barbican_tempest.enable_multiple_secret_stores:
             raise cls.skipException("enable_multiple_secret_stores is not "
                                     "configured.  Skipping RBAC tests.")
@@ -125,6 +126,18 @@ class ProjectMemberTests(base.BarbicanV1RbacBase, BarbicanV1RbacSecretStores):
         self.assertTrue(resp['global_default'])
 
     def test_get_preferred_secret_store(self):
+        # First use project admin to set preferred secret store
+        resp = self.do_request('list_secret_stores')
+        secret_store_id = self.ref_to_uuid(
+            resp['secret_stores'][0]['secret_store_ref']
+        )
+        admin_client = self.os_project_admin.secret_v1.SecretStoresClient()
+        self.do_request('set_preferred_secret_store',
+                        client=admin_client,
+                        secret_store_id=secret_store_id)
+
+        # Check that other users in project can view the newly set
+        # preferred secret store
         resp = self.do_request('get_preferred_secret_store')
         self.assertEqual('ACTIVE', resp['status'])
 
@@ -142,7 +155,7 @@ class ProjectMemberTests(base.BarbicanV1RbacBase, BarbicanV1RbacSecretStores):
         secret_store_id = self.ref_to_uuid(
             resp['secret_stores'][0]['secret_store_ref']
         )
-        self.do_request('unset_peferred_secret_store',
+        self.do_request('unset_preferred_secret_store',
                         expected_status=exceptions.Forbidden,
                         secret_store_id=secret_store_id)
 
@@ -172,11 +185,10 @@ class ProjectAdminTests(ProjectMemberTests):
         )
         self.do_request('set_preferred_secret_store',
                         secret_store_id=secret_store_id)
-        self.do_request('unset_peferred_secret_store',
+        self.do_request('unset_preferred_secret_store',
                         secret_store_id=secret_store_id)
-        resp = self.do_request('get_preferred_secret_store')
+        self.do_request('get_preferred_secret_store',
-        self.assertEqual(secret_store_id,
+                        expected_status=exceptions.NotFound)
-                         self.ref_to_uuid(resp['secret_store_ref']))
 
 
 class ProjectReaderTests(ProjectMemberTests):