Set fluentd output to elasticsearch to use elasticsearch_address

Haproxy binds the elasticsearch service to kolla_internal_vip_address but
the output templates for fluentd (td-agent) point to a non-existent
kolla_external_vip_address.

Output should also be able to be sent to an external elasticsearch
instance (as per the documentation regarding overriding
elasticsearch_address)

Change these settings so that fluentd outputs to either
the default elasticsearch_address (i.e. kolla_internal_vip_address) or to
the external elasticsearch instance.

Closes-Bug: #1673990
Change-Id: I081533ae8ea9aad186e9c44e1dee069729931453

ansible/roles/common/tasks/config.yml

@@ -42,7 +42,8 @@
     - name: "00-local"
       enabled: true
     - name: "01-es"
-      enabled: "{{ enable_elasticsearch }}"
+      enabled: "{{ enable_elasticsearch | bool or
+                ( elasticsearch_address != kolla_internal_vip_address ) | bool }}"
 
 - name: Copying over fluentd format config files
   template:

ansible/roles/common/templates/conf/output/00-local.conf.j2

@@ -8,10 +8,11 @@
     append true
     compress gzip
   </store>
-{% if enable_elasticsearch | bool %}
+{% if enable_elasticsearch | bool or
+      elasticsearch_address != kolla_internal_vip_address %}
   <store>
        type elasticsearch
-       host {{ kolla_external_vip_address }}
+       host {{ elasticsearch_address }}
        port {{ elasticsearch_port }}
        logstash_format true
        logstash_prefix flog
@@ -32,10 +33,11 @@
     append true
     compress gzip
   </store>
-{% if enable_elasticsearch | bool %}
+{% if enable_elasticsearch | bool or
+      elasticsearch_address != kolla_internal_vip_address %}
   <store>
        type elasticsearch
-       host {{ kolla_external_vip_address }}
+       host {{ elasticsearch_address }}
        port {{ elasticsearch_port }}
        logstash_format true
        logstash_prefix flog

ansible/roles/common/templates/conf/output/01-es.conf.j2

@@ -2,7 +2,7 @@
     type copy
     <store>
        type elasticsearch
-       host {{ kolla_external_vip_address }} 
+       host {{ elasticsearch_address }}
        port {{ elasticsearch_port }}
        logstash_format true
        logstash_prefix flog

ansible/roles/common/templates/fluentd.json.j2

@@ -60,7 +60,8 @@
             "dest": "/etc/td-agent/format/wsgi_python.conf",
             "owner": "td-agent",
             "perm": "0600"
-        },{% if enable_elasticsearch | bool %}
+        },{% if enable_elasticsearch | bool or
+                ( elasticsearch_address != kolla_internal_vip_address ) | bool %}
         {
             "source": "{{ container_config_directory }}/output/01-es.conf",
             "dest": "/etc/td-agent/output/01-es.conf",