Missing configuration for Trove single tenant

The nova_proxy_* options are not needed when Trove single tenant
functionnality is not used.

The current way how Kolla configure trove-taskmanager.conf is to use the
user tenant so the nova_proxy_* options are not required by default.

I added the "enable_trove_singletenant" option to enable the single tenant
functionnality if required and complete the configuration to make it works.

When enable_trove_singletenant is true, the below configuration will be
applied to trove-task-manager.conf configuration file:

nova_proxy_admin_pass = {{ trove_keystone_password }}
nova_proxy_admin_tenant_name = services
nova_proxy_admin_user = trove
remote_nova_client = \
    trove.common.single_tenant_remote.nova_client_trove_admin
remote_cinder_client = \
    trove.common.single_tenant_remote.cinder_client_trove_admin
remote_neutron_client = \
    trove.common.single_tenant_remote.neutron_client_trove_admin

Change-Id: I9858acd9486a3f6a07c1edad14fde12f49df772b
Closes-Bug: #1743394

ansible/group_vars/all.yml

@@ -466,6 +466,7 @@ enable_tacker: "no"
 enable_telegraf: "no"
 enable_tempest: "no"
 enable_trove: "no"
+enable_trove_singletenant: "no"
 enable_vitrage: "no"
 enable_vmtp: "no"
 enable_watcher: "no"

ansible/roles/trove/templates/trove-taskmanager.conf.j2

@@ -3,9 +3,14 @@ debug = {{ trove_logging_debug }}
 
 log_dir = /var/log/kolla/trove
 
+{% if enable_trove_singletenant | bool %}
 nova_proxy_admin_pass = {{ trove_keystone_password }}
 nova_proxy_admin_tenant_name = services
 nova_proxy_admin_user = trove
+remote_nova_client = trove.common.single_tenant_remote.nova_client_trove_admin
+remote_cinder_client = trove.common.single_tenant_remote.cinder_client_trove_admin
+remote_neutron_client = trove.common.single_tenant_remote.neutron_client_trove_admin
+{% endif %}
 taskmanager_manager = trove.taskmanager.manager.Manager
 
 transport_url = {{ rpc_transport_url }}

etc/kolla/globals.yml

@@ -225,6 +225,7 @@ kolla_internal_vip_address: "10.10.10.254"
 #enable_tacker: "no"
 #enable_tempest: "no"
 #enable_trove: "no"
+#enable_trove_singletenant: "no"
 #enable_vitrage: "no"
 #enable_vmtp: "no"
 #enable_watcher: "no"

releasenotes/notes/add-trove-singletenant-dd02a7b7cc1a4f99.yaml

@@ -0,0 +1,6 @@
+---
+features:
+  - |
+    Add "enable_trove_singletenant" option to enable the Trove single
+    tenant functionnality. This feature will allow Trove to create
+    Nova instances in a different tenant than the user tenant.