Enable single systemd service for Pulp

closes #7006

CHANGES/7006.feature

@@ -0,0 +1 @@
+Added a single systemd service to restart Pulp

roles/pulp_api/templates/pulpcore-api.service.j2

@@ -2,6 +2,10 @@
 Description=Pulp WSGI Server
 After=network-online.target
 Wants=network-online.target
+# When systemd stops or restarts the meta pulpcore.service, the action is propagated to this service
+PartOf=pulpcore.service
+# Start this service after the pulpcore.service starts
+After=pulpcore.service
 
 [Service]
 Type=notify

roles/pulp_common/handlers/restart_all_pulp.yml

@@ -1,29 +1,9 @@
 ---
-# We cannot pass wildcards to the systemd module, so we have
-# this hack for our dynamic include_roles users.
-#
-# The handlers will be flushed during pulp_database, before
-# pulp_workers is called. But said users' ansible does not know
-# the number of pulp-workers yet.
-#
-# TODO: The Pulp services *should* be refactored into a
-# systemd multi-service app. That would mean a single task would
-# restart all of Pulp.
-- name: Reload systemd
+- name: Restart pulpcore service
   systemd:
     daemon_reload: true
-  become: true
-
-- name: Get services
-  service_facts:
-
-- name: Restart all pulpcore* services
-  systemd:
-    daemon_reload: true
-    name: "{{ item.value.name }}"
+    name: "pulpcore.service"
     state: restarted
-  when: "item.value.name != 'pulpcore-worker@.service'"
-  with_dict: '{{ ansible_facts.services|dict2items|selectattr("key", "contains", "pulpcore")|list|items2dict }}'
   become: true
 
 - name: Delete symlink from old artifact directory location

roles/pulp_common/tasks/main.yml

@@ -101,3 +101,21 @@
 - import_tasks: repos.yml
 - import_tasks: install.yml
 - import_tasks: configure.yml
+
+- name: Install pulpcore service
+  template:
+    src: pulpcore.service.j2
+    dest: /lib/systemd/system/pulpcore.service
+    owner: root
+    group: root
+    mode: 0644
+  become: true
+  notify: Restart all Pulp services
+
+- name: Set state of pulpcore app
+  systemd:
+    daemon_reload: true
+    name: pulpcore.service
+    state: started
+    enabled: true
+  become: true

roles/pulp_common/templates/pulpcore.service.j2

@@ -0,0 +1,14 @@
+[Unit]
+Description=Pulpcore Application
+
+[Service]
+# The dummy program will exit
+Type=oneshot
+# Execute a dummy program
+ExecStart=/bin/true
+# This service shall be considered active after start
+RemainAfterExit=yes
+
+[Install]
+# Components of this application should be started at boot time
+WantedBy=multi-user.target

roles/pulp_content/templates/pulpcore-content.service.j2

@@ -2,6 +2,10 @@
 Description=Pulp Content App
 After=network-online.target
 Wants=network-online.target
+# When systemd stops or restarts the meta pulpcore.service, the action is propagated to this service
+PartOf=pulpcore.service
+# Start this service after the pulpcore.service starts
+After=pulpcore.service
 
 [Service]
 Type=notify

roles/pulp_health_check/tasks/main.yml

@@ -12,7 +12,7 @@
 - name: Checking Pulp services
   fail:
     msg: "{{ item.value.name }} state: {{ item.value.state }}"
-  when: "item.value.name != 'pulpcore-worker@.service' and item.value.state != 'running'"
+  when: "item.value.name not in ['pulpcore-worker@.service', 'pulpcore.service'] and item.value.state != 'running'"
   with_dict: '{{ ansible_facts.services|dict2items|selectattr("key", "contains", "pulpcore")|list|items2dict }}'
 
 - name: Ensure Pulp is up and healthy

roles/pulp_resource_manager/templates/pulpcore-resource-manager.service.j2

@@ -2,6 +2,10 @@
 Description=Pulp Resource Manager
 After=network-online.target
 Wants=network-online.target
+# When systemd stops or restarts the meta pulpcore.service, the action is propagated to this service
+PartOf=pulpcore.service
+# Start this service after the pulpcore.service starts
+After=pulpcore.service
 
 [Service]
 Environment="DJANGO_SETTINGS_MODULE=pulpcore.app.settings"

roles/pulp_workers/templates/pulpcore-worker@.service.j2

@@ -2,6 +2,10 @@
 Description=Pulp Worker
 After=network-online.target
 Wants=network-online.target
+# When systemd stops or restarts the meta pulpcore.service, the action is propagated to this service
+PartOf=pulpcore.service
+# Start this service after the pulpcore.service starts
+After=pulpcore.service
 
 [Service]
 EnvironmentFile=-/etc/default/pulp-workers