Add function for checking sanity of nodes to upgrade

Move sanity checks logic for upgrading node into separate
function.

Change-Id: Ifa46753f0bed18a0e25887c2a07445145011dad4
Related-bug: 1583063

octane/commands/upgrade_node.py

@@ -26,15 +26,10 @@ from octane.util import patch
 LOG = logging.getLogger(__name__)
 
 
-def upgrade_node(env_id, node_ids, isolated=False, network_template=None,
-                 provision=True, roles=None, live_migration=True):
-    # From check_deployment_status
-    env = environment_obj.Environment(env_id)
-    nodes = [node_obj.Node(node_id) for node_id in node_ids]
-
-    # Sanity check
+def check_sanity(env_id, nodes):
     one_orig_id = None
     for node in nodes:
+        node_id = node.data['id']
         orig_id = node.data['cluster']
         if orig_id == env_id:
             raise Exception(
@@ -48,14 +43,16 @@ def upgrade_node(env_id, node_ids, isolated=False, network_template=None,
                     orig_id, one_orig_id,
                 )
             one_orig_id = orig_id
-    # NOTE(ogelbukh): Another sanity check: we can't upgrade single controller
-    # except the first one, otherwise deployment fails
-    # TODO(ogelbukh): Investigate and solve the root cause of the issue that
-    # prevents upgrade of a single controller
-    if not isolated and len(nodes) == 1 and \
-            'controller' in nodes[0].data['roles']:
-        raise Exception("Cannot upgrade single non-isolated controller {0}"
-                        .format(nodes[0].data['id']))
+
+
+def upgrade_node(env_id, node_ids, isolated=False, network_template=None,
+                 provision=True, roles=None, live_migration=True):
+    # From check_deployment_status
+    env = environment_obj.Environment(env_id)
+    nodes = [node_obj.Node(node_id) for node_id in node_ids]
+
+    check_sanity(env_id, nodes)
+
     # NOTE(ogelbukh): patches and scripts copied to nailgun container
     # for later use
     copy_patches_folder_to_nailgun()

octane/tests/test_upgrade_node.py

@@ -89,3 +89,39 @@ def test_upgrade_node(mocker, node_ids, isolated, network_template,
         mock_deploy_nodes.assert_called_once()
     else:
         mock_deploy_changes.assert_called_once()
+
+
+@pytest.mark.parametrize('node_data,expected_error', [
+    ([{
+        'id': 'test-node',
+        'cluster': None,
+    }], None),
+    ([{
+        'id': 'test-node',
+        'cluster': 'test-env',
+    }], Exception),
+    ([{
+        'id': 'test-node',
+        'cluster': 'test-env-1',
+    }, {
+        'id': 'another-test-node',
+        'cluster': 'test-env-2'
+    }], Exception),
+])
+def test_check_sanity(mocker, node, node_data, expected_error):
+    test_env_id = "test-env"
+    mock_nodes = []
+    for data in node_data:
+        mock_node = mocker.Mock(data=data)
+        mock_nodes.append(mock_node)
+    if expected_error:
+        with pytest.raises(expected_error) as exc_info:
+            upgrade_node.check_sanity(test_env_id, mock_nodes)
+        if len(mock_nodes) == 1:
+            assert "Cannot upgrade node with ID %s:" \
+                in exc_info.value.args[0]
+        else:
+            assert "Not upgrading nodes from different clusters" \
+                in exc_info.value.args[0]
+    else:
+        assert upgrade_node.check_sanity(test_env_id, mock_nodes) is None