Use systemd_service role for overrides

Replace placing templates for systemd overrides with
systemd_service role, that will handle overrides for us in more
convenient and unified way.

Change-Id: I2759b1949e9ecc98953f414c6f9838aed7dd8499

defaults/main.yml

@@ -284,6 +284,12 @@ rabbitmq_port_bindings:
   tcp_listeners:
     "0.0.0.0": 5672
 
+rabbitmq_init_overrides:
+  Service:
+    LimitNOFILE: "{{ rabbitmq_ulimit }}"
+    Restart: on-failure
+    RestartSec: 2
+
 # Mnesia configuration
 # The Mnesia dump_log_write_threshold option controls
 # how often the dumping occurs

releasenotes/notes/rabbitmq_init_overrides-74ce479a2dcf304c.yaml

@@ -0,0 +1,6 @@
+---
+features:
+  - |
+    Added variable ``rabbitmq_init_overrides`` that allows to control rabbitmq
+    overrides that will be applied to the systemd service.
+    Previously values were hardcoded without possibility for override.

tasks/rabbitmq_post_install.yml

@@ -13,16 +13,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-- name: Create rabbitmq systemd service config dir
-  file:
-    path: "/etc/systemd/system/rabbitmq-server.service.d"
-    state: "directory"
-    group: "root"
-    owner: "root"
-    mode: "0755"
-  tags:
-    - rabbitmq-config
-
 - name: Create rabbitmq config
   register: rabbit_config
   template:
@@ -45,32 +35,26 @@
     path: /etc/rabbitmq/rabbitmq.config
     state: absent
 
-- name: Apply resource limits (systemd)
-  template:
-    src: "limits.conf.j2"
-    dest: "/etc/systemd/system/rabbitmq-server.service.d/limits.conf"
-  register: rabbit_resource_limit
-  tags:
-    - rabbitmq-config
+# TODO(noonedeadpunk): Remove task after Z release
+- name: Remove old systemd overrides
+  file:
+    path: "/etc/systemd/system/rabbitmq-server.service.d/{{ item }}"
+    state: absent
+  with_items:
+    - limits.conf
+    - systemd-restart-on-failure.conf
+  when: rabbitmq_upgrade | bool
 
-- name: Add automatic restart on failure
-  template:
-    src: systemd-restart-on-failure.conf.j2
-    dest: "/etc/systemd/system/rabbitmq-server.service.d/systemd-restart-on-failure.conf"
-  register: rabbit_restart_on_failure
-  tags:
-    - rabbitmq-config
-
-- name: Reload the systemd daemon
-  systemd:
-    daemon_reload: yes
-  when:
-    - rabbit_resource_limit is changed
-    - rabbit_restart_on_failure is changed
-  tags:
-    - rabbitmq-config
-    # don't trigger ANSIBLE0016
-    - skip_ansible_lint
+- name: Apply systemctl overrides
+  import_role:
+    name: systemd_service
+  vars:
+    systemd_user_name: "{{ rabbit_system_user_name }}"
+    systemd_group_name: "{{ rabbit_system_group_name }}"
+    systemd_services:
+      - service_name: rabbitmq-server
+        systemd_overrides_only: true
+        systemd_overrides: "{{ rabbitmq_init_overrides }}"
 
 - name: Configure rabbitmq plugins
   community.rabbitmq.rabbitmq_plugin:

templates/limits.conf.j2

@@ -1,4 +0,0 @@
-# {{ ansible_managed }}
-
-[Service]
-LimitNOFILE={{ rabbitmq_ulimit }}

templates/rabbitmq-server.service.j2

@@ -1,18 +0,0 @@
-[Unit]
-Description=RabbitMQ broker
-After=syslog.target network.target
-Conflicts=epmd.socket
-Conflicts=epmd.service
-
-[Service]
-Type=notify
-User={{ rabbit_system_user_name }}
-Group={{ rabbit_system_group_name }}
-LimitNOFILE=65535
-NotifyAccess=all
-WorkingDirectory=/var/lib/rabbitmq
-ExecStart=/usr/sbin/rabbitmq-server
-ExecStop=/usr/sbin/rabbitmqctl stop
-
-[Install]
-WantedBy=multi-user.target

templates/systemd-restart-on-failure.conf.j2

@@ -1,4 +0,0 @@
-# {{ ansible_managed }}
-[Service]
-Restart=on-failure
-RestartSec=2