NSX|V3 remove lbaas import to allow the plugin to work without lbaas

Replace LBaaS constants/classes with local ones or mocks to allow the
plugin to work without checking out the neutron-lbaas.

Change-Id: Iadf21ffcf7d4db8ab4e429b1daab2f8eccae1bc6

vmware_nsx/services/lbaas/lb_const.py

@@ -124,3 +124,8 @@ LOADBALANCERS = 'loadbalancers'
 LISTENERS = 'listeners'
 POOLS = 'pools'
 MEMBERS = 'members'
+
+ONLINE = 'ONLINE'
+OFFLINE = 'OFFLINE'
+DEGRADED = 'DEGRADED'
+DISABLED = 'DISABLED'

vmware_nsx/services/lbaas/lbaas_mocks.py

@@ -0,0 +1,21 @@
+# Copyright 2018 VMware, Inc.
+# All Rights Reserved
+#
+#    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.
+
+# This file contains LBaaS mocks, to allow the vmware nsx plugins to work when
+# LBaaS code does not exist, and LBaaS is not configured in neutron
+
+
+class LoadBalancer(object):
+    pass

vmware_nsx/services/lbaas/nsx_v3/implementation/loadbalancer_mgr.py

@@ -18,8 +18,6 @@ from neutron_lib import exceptions as n_exc
 from oslo_log import log as logging
 from oslo_utils import excutils
 
-from neutron_lbaas.services.loadbalancer import constants
-
 from vmware_nsx._i18n import _
 from vmware_nsx.db import db as nsx_db
 from vmware_nsx.services.lbaas import base_mgr
@@ -115,21 +113,21 @@ class EdgeLoadBalancerManagerFromDict(base_mgr.Nsxv3LoadbalancerBaseManager):
     def _nsx_status_to_lb_status(self, nsx_status):
         if not nsx_status:
             # default fallback
-            return constants.ONLINE
+            return lb_const.ONLINE
 
         # Statuses that are considered ONLINE:
         if nsx_status.upper() in ['UP', 'UNKNOWN', 'PARTIALLY_UP',
                                   'NO_STANDBY']:
-            return constants.ONLINE
+            return lb_const.ONLINE
         # Statuses that are considered OFFLINE:
         if nsx_status.upper() in ['PRIMARY_DOWN', 'DETACHED', 'DOWN', 'ERROR']:
-            return constants.OFFLINE
+            return lb_const.OFFLINE
         if nsx_status.upper() == 'DISABLED':
-            return constants.DISABLED
+            return lb_const.DISABLED
 
         # default fallback
         LOG.debug("NSX LB status %s - interpreted as ONLINE", nsx_status)
-        return constants.ONLINE
+        return lb_const.ONLINE
 
     def get_lb_pool_members_statuses(self, nsx_pool_id, members_statuses):
         # Combine the NSX pool members data and the NSX statuses to provide

vmware_nsx/services/lbaas/octavia/octavia_listener.py

@@ -25,10 +25,14 @@ from oslo_log import log as logging
 import oslo_messaging as messaging
 from oslo_messaging.rpc import dispatcher
 
-from neutron_lbaas.db.loadbalancer import models
-
 from vmware_nsx.services.lbaas.octavia import constants
 
+try:
+    from neutron_lbaas.db.loadbalancer import models
+except ImportError:
+    # LBaaS project not found.
+    from vmware_nsx.services.lbaas import lbaas_mocks as models
+
 LOG = logging.getLogger(__name__)
 
 
@@ -342,6 +346,10 @@ class NSXOctaviaStatisticsCollector(object):
         case that the plugin is currently unavailable, but entries already
         exist on the DB.
         """
+        if not hasattr(models.LoadBalancer, '__tablename__'):
+            # No neutron-lbaas on this deployment
+            return []
+
         nl_loadbalancers = context.session.query(models.LoadBalancer).all()
         return [lb.id for lb in nl_loadbalancers]