roles/memcached: Initial work on the memcached role.

roles/archweb: Make archweb install and use it's own memcached service, running as the archweb user and using a socket.

roles/archweb/files/archweb-memcached.service

+[Unit]
+Description=Archweb Memcached Daemon
+After=network.target
+
+[Service]
+User=archweb
+Group=memcached
+# Remove '-l 127.0.0.1' to listen on all addresses
+ExecStart=/usr/bin/memcached -s /run/memcached/archweb.sock -o modern
+Restart=always
+PrivateTmp=yes
+PrivateDevices=yes
+ProtectSystem=full
+MemoryDenyWriteExecute=yes
+
+[Install]
+WantedBy=multi-user.target

roles/archweb/tasks/main.yml

 ---
 
 - name: install git
-  pacman: name=git,memcached,python2,python2-virtualenv,uwsgi-plugin-python2 state=present
+  pacman: name=git,python2,python2-virtualenv,uwsgi-plugin-python2 state=present
 
 - name: make archweb user
   user: name=archweb shell=/bin/false home="{{ archweb_dir }}" createhome=no groups=uwsgi
@@ -48,11 +48,22 @@
     - daemon reload
   when: services
 
+- name: copy archweb memcached service
+  copy: src="archweb-memcached.service" dest="/etc/systemd/system/archweb-memcached.service" owner=root group=root mode=0644
+  notify:
+    - daemon reload
+  when: not services
+
 - name: configure archweb
   template: src=local_settings.py.j2 dest=/srv/http/archweb/local_settings.py owner=archweb group=archweb mode=0660
 
 - name: deploy archweb
   template: src=archweb.ini.j2 dest=/etc/uwsgi/vassals/archweb.ini owner=archweb group=http mode=0644
+  when: not services
+
+- name: start and enable archweb memcached service
+  service: name="archweb-memcached.service" enabled=yes state=started
+  when: not services
 
 - name: start and enable archweb services
   service: name="{{ item }}" enabled=yes state=started

roles/archweb/templates/local_settings.py.j2

@@ -26,7 +26,7 @@ DATABASES = {
 CACHES = {
     'default': {
         'BACKEND' : 'django.core.cache.backends.memcached.MemcachedCache',
-        'LOCATION': '127.0.0.1:11211',
+        'LOCATION': 'unix:/run/memcached/archweb.sock',
     }
 }
 

roles/memcached/tasks/main.yml

+---
+
+- name: install memcached
+  pacman: name=memcached state=present
+
+- name: put memcached.conf into tmpfiles
+  template: src=memcached-tmpfiles.d.j2 dest=/etc/tmpfiles.d/memcached.conf owner=root group=root mode=0644
+  register: memcachedtmpfiles
+
+- name: use tmpfiles.d/memcached.conf
+  command: systemd-tmpfiles --create
+  when: memcachedtmpfiles.changed

roles/memcached/templates/memcached-tmpfiles.d.j2

+d /run/memcached 0775 memcached memcached - -