Fixed haproxy backend config issue

The change updates the haproxy configs to use backends with a
default of an empty array. This is needed to ensure that the backends
are not being assumed to have some value. In the current system if an
inventory item did not exist the rendered backend would be a jinja
string which would cause the haproxy play to fail.

Closes-Bug: #1513455

Change-Id: I221dbd910c75c2e41c98a33e1c38c7f69718b544
Signed-off-by: Kevin Carter <kevin.carter@rackspace.com>
(cherry picked from commit 589650228b)

playbooks/vars/configs/haproxy_config.yml

@@ -27,8 +27,8 @@ keystone_ssl_public: "{% if keystone_ssl is defined and keystone_ssl | bool and
 haproxy_service_configs:
   - service:
       haproxy_service_name: galera
-      haproxy_backend_nodes: "{{ [groups['galera_all'][0]] }}"  # list expected
-      haproxy_backup_nodes: "{{ groups['galera_all'][1:] }}"
+      haproxy_backend_nodes: "{{ [groups['galera_all'][0]] | default([]) }}"  # list expected
+      haproxy_backup_nodes: "{{ groups['galera_all'][1:] | default([]) }}"
       haproxy_port: 3306
       haproxy_balance_type: tcp
       haproxy_timeout_client: 5000s
@@ -37,7 +37,7 @@ haproxy_service_configs:
         - "mysql-check user {{ galera_monitoring_user }}"
   - service:
       haproxy_service_name: glance_api
-      haproxy_backend_nodes: "{{ groups['glance_api'] }}"
+      haproxy_backend_nodes: "{{ groups['glance_api'] | default([]) }}"
       haproxy_port: 9292
       haproxy_balance_type: http
       haproxy_backend_options:
@@ -46,12 +46,12 @@ haproxy_service_configs:
         - "httplog"
   - service:
       haproxy_service_name: glance_registry
-      haproxy_backend_nodes: "{{ groups['glance_registry'] }}"
+      haproxy_backend_nodes: "{{ groups['glance_registry'] | default([]) }}"
       haproxy_port: 9191
       haproxy_balance_type: http
   - service:
       haproxy_service_name: heat_api_cfn
-      haproxy_backend_nodes: "{{ groups['heat_api_cfn'] }}"
+      haproxy_backend_nodes: "{{ groups['heat_api_cfn'] | default([]) }}"
       haproxy_port: 8000
       haproxy_balance_type: http
       haproxy_backend_options:
@@ -60,7 +60,7 @@ haproxy_service_configs:
        - "httplog"
   - service:
       haproxy_service_name: heat_api_cloudwatch
-      haproxy_backend_nodes: "{{ groups['heat_api_cloudwatch'] }}"
+      haproxy_backend_nodes: "{{ groups['heat_api_cloudwatch'] | default([]) }}"
       haproxy_port: 8003
       haproxy_balance_type: http
       haproxy_backend_options:
@@ -69,7 +69,7 @@ haproxy_service_configs:
        - "httplog"
   - service:
       haproxy_service_name: heat_api
-      haproxy_backend_nodes: "{{ groups['heat_api'] }}"
+      haproxy_backend_nodes: "{{ groups['heat_api'] | default([]) }}"
       haproxy_port: 8004
       haproxy_balance_type: http
       haproxy_backend_options:
@@ -78,7 +78,7 @@ haproxy_service_configs:
        - "httplog"
   - service:
       haproxy_service_name: keystone_admin
-      haproxy_backend_nodes: "{{ groups['keystone_all'] }}"
+      haproxy_backend_nodes: "{{ groups['keystone_all'] | default([]) }}"
       haproxy_port: 35357
       haproxy_ssl: "{% if haproxy_ssl | bool and keystone_service_adminuri_proto == 'https' %}true{% else %}false{% endif %}"
       haproxy_balance_type: "{{ (keystone_ssl_admin | bool) | ternary('tcp', 'http') }}"
@@ -86,7 +86,7 @@ haproxy_service_configs:
       haproxy_backend_options: "{{ (keystone_ssl_admin | bool) | ternary(haproxy_backend_options_https, haproxy_backend_options_http) }}"
   - service:
       haproxy_service_name: keystone_service
-      haproxy_backend_nodes: "{{ groups['keystone_all'] }}"
+      haproxy_backend_nodes: "{{ groups['keystone_all'] | default([])  }}"
       haproxy_bind: "{% if internal_lb_vip_address == external_lb_vip_address %}*{% else %}{{ external_lb_vip_address }}{% endif %}"
       haproxy_port: 5000
       haproxy_ssl: "{% if haproxy_ssl | bool and keystone_service_publicuri_proto == 'https' %}true{% else %}false{% endif %}"
@@ -95,7 +95,7 @@ haproxy_service_configs:
       haproxy_backend_options: "{{ (keystone_ssl_public | bool) | ternary(haproxy_backend_options_https, haproxy_backend_options_http) }}"
   - service:
       haproxy_service_name: neutron_server
-      haproxy_backend_nodes: "{{ groups['neutron_server'] }}"
+      haproxy_backend_nodes: "{{ groups['neutron_server'] | default([]) }}"
       haproxy_port: 9696
       haproxy_balance_type: http
       haproxy_backend_options:
@@ -104,7 +104,7 @@ haproxy_service_configs:
        - "httplog"
   - service:
       haproxy_service_name: nova_api_metadata
-      haproxy_backend_nodes: "{{ groups['nova_api_metadata'] }}"
+      haproxy_backend_nodes: "{{ groups['nova_api_metadata'] | default([]) }}"
       haproxy_port: 8775
       haproxy_balance_type: http
       haproxy_backend_options:
@@ -112,7 +112,7 @@ haproxy_service_configs:
        - "httplog"
   - service:
       haproxy_service_name: nova_api_os_compute
-      haproxy_backend_nodes: "{{ groups['nova_api_os_compute'] }}"
+      haproxy_backend_nodes: "{{ groups['nova_api_os_compute'] | default([]) }}"
       haproxy_port: 8774
       haproxy_balance_type: http
       haproxy_backend_options:
@@ -121,7 +121,7 @@ haproxy_service_configs:
        - "httplog"
   - service:
       haproxy_service_name: nova_console
-      haproxy_backend_nodes: "{{ groups['nova_console'] }}"
+      haproxy_backend_nodes: "{{ groups['nova_console'] | default([]) }}"
       haproxy_ssl: "{% if haproxy_ssl | bool and nova_spice_html5proxy_base_proto == 'https' %}true{% else %}false{% endif %}"
       haproxy_port: 6082
       haproxy_balance_type: tcp
@@ -130,7 +130,7 @@ haproxy_service_configs:
       haproxy_balance_alg: source
   - service:
       haproxy_service_name: nova_console_novnc
-      haproxy_backend_nodes: "{{ groups['nova_console'] }}"
+      haproxy_backend_nodes: "{{ groups['nova_console'] | default([]) }}"
       haproxy_ssl: "{% if haproxy_ssl | bool and nova_novncproxy_proto == 'https' %}true{% else %}false{% endif %}"
       haproxy_port: 6080
       haproxy_balance_type: tcp
@@ -139,7 +139,7 @@ haproxy_service_configs:
       haproxy_balance_alg: source
   - service:
       haproxy_service_name: cinder_api
-      haproxy_backend_nodes: "{{ groups['cinder_api'] }}"
+      haproxy_backend_nodes: "{{ groups['cinder_api'] | default([]) }}"
       haproxy_port: 8776
       haproxy_balance_type: http
       haproxy_backend_options:
@@ -148,7 +148,7 @@ haproxy_service_configs:
        - "httplog"
   - service:
       haproxy_service_name: horizon
-      haproxy_backend_nodes: "{{ groups['horizon_all'] }}"
+      haproxy_backend_nodes: "{{ groups['horizon_all'] | default([]) }}"
       haproxy_port: 80
       haproxy_balance_type: http
       haproxy_backend_options:
@@ -157,7 +157,7 @@ haproxy_service_configs:
        - "httplog"
   - service:
       haproxy_service_name: horizon_ssl
-      haproxy_backend_nodes: "{{ groups['horizon_all'] }}"
+      haproxy_backend_nodes: "{{ groups['horizon_all'] | default([]) }}"
       haproxy_port: 443
       haproxy_balance_type: tcp
       haproxy_balance_alg: source
@@ -165,18 +165,18 @@ haproxy_service_configs:
        - "ssl-hello-chk"
   - service:
       haproxy_service_name: swift_proxy
-      haproxy_backend_nodes: "{{ groups['swift_proxy'] }}"
+      haproxy_backend_nodes: "{{ groups['swift_proxy'] | default([]) }}"
       haproxy_balance_alg: source
       haproxy_port: 8080
       haproxy_balance_type: http
   - service:
       haproxy_service_name: repo_all
-      haproxy_backend_nodes: "{{ groups['pkg_repo'] }}"
+      haproxy_backend_nodes: "{{ groups['pkg_repo'] | default([]) }}"
       haproxy_port: 8181
       haproxy_backend_port: 8181
       haproxy_balance_type: http
   - service:
       haproxy_service_name: ceilometer_api
-      haproxy_backend_nodes: "{{ groups['ceilometer_api_container'] }}"
+      haproxy_backend_nodes: "{{ groups['ceilometer_api_container'] | default([]) }}"
       haproxy_port: 8777
       haproxy_balance_type: http