Support configuration of custom fluentd outputs

In some scenarios it may be useful to configure custom fluentd outputs
to forward logs to a logging service other than elasticsearch.

This change supports configuration of fluentd outputs by placing
output configuration files in /etc/kolla/config/fluentd/output/*.conf.

Change-Id: I3c0b271d88dbb307ba3a23546e29c72e8baeca55
Implements: blueprint fluentd-custom-outputs

ansible/roles/common/handlers/main.yml

@@ -17,6 +17,7 @@
     - config_json.changed | bool
       or fluentd_input.changed | bool
       or fluentd_output.changed | bool
+      or fluentd_output_custom.changed | bool
       or fluentd_format.changed | bool
       or fluentd_filter.changed | bool
       or fluentd_td_agent.changed | bool

ansible/roles/common/tasks/config.yml

@@ -53,6 +53,23 @@
   notify:
     - Restart fluentd container
 
+- name: Find custom fluentd output config files
+  local_action:
+    module: find
+    path: "{{ node_custom_config }}/fluentd/output"
+    pattern: "*.conf"
+  run_once: True
+  register: find_custom_fluentd_outputs
+
+- name: Copying over custom fluentd output config files
+  template:
+    src: "{{ item.path }}"
+    dest: "{{ node_config_directory }}/fluentd/output/{{ item.path | basename }}"
+  register: fluentd_output_custom
+  with_items: "{{ find_custom_fluentd_outputs.files }}"
+  notify:
+    - Restart fluentd container
+
 - name: Copying over fluentd format config files
   template:
     src: "conf/format/{{ item }}.conf.j2"

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

@@ -70,17 +70,12 @@
             "dest": "{{ fluentd_dir }}/format/wsgi_access.conf",
             "owner": "{{ fluentd_user }}",
             "perm": "0600"
-        },{% if enable_elasticsearch | bool or
-                ( elasticsearch_address != kolla_internal_vip_address ) | bool %}
-        {
-            "source": "{{ container_config_directory }}/output/01-es.conf",
-            "dest": "{{ fluentd_dir }}/output/01-es.conf",
-            "owner": "{{ fluentd_user }}",
-            "perm": "0600"
-        },{% endif %}
+        },
+        {# Copy all configuration files in output/ directory to include #}
+        {# custom output configs. #}
         {
-            "source": "{{ container_config_directory }}/output/00-local.conf",
-            "dest": "{{ fluentd_dir }}/output/00-local.conf",
+            "source": "{{ container_config_directory }}/output/*.conf",
+            "dest": "{{ fluentd_dir }}/output/",
             "owner": "{{ fluentd_user }}",
             "perm": "0600"
         }

doc/source/reference/central-logging-guide.rst

@@ -154,3 +154,13 @@ item can be exported separately by selecting it in the menu. All of the items
 can also be exported at once by choosing *export everything* option.
 In the same tab (Settings - Objects) one can also import saved items by
 choosing *import* option.
+
+Custom log forwarding
+=====================
+
+In some scenarios it may be useful to forward logs to a logging service other
+than elasticsearch.  This can be done by configuring custom fluentd outputs.
+
+Configuration of custom fluentd outputs is possible by placing output
+configuration files in ``/etc/kolla/config/fluentd/output/*.conf`` on the
+control host.

releasenotes/notes/fluentd-custom-output-config-21f990cacbf3adb1.yaml

+---
+features:
+  - |
+    Adds ability to configure custom fluentd outputs.
+
+    In some scenarios it may be useful to configure custom fluentd outputs
+    to forward logs to a logging service other than elasticsearch.
+
+    Configuration of custom fluentd outputs is possible by placing
+    output configuration files in /etc/kolla/config/fluentd/output/\*.conf.