Origin : Production documents

Medias_Union : Documents pool as it's seen

Medias_RW : Modifications (CUD)

⇒  ls -lt origin/prod/observer/srv01/var/uploads/ | more
juil. 24 10:12 55b1f36792b81.pdf
juil. 24 09:50 55b1ee2e5a0af.pdf
juil. 23 15:11 55b0e80adf713.pdf
...

⇒  ls -lt env_14/medias_rw/prod/observer/srv01/var/uploads/document/ | more
total 104
juil. 30 16:14 55ba31301dd84.pdf
profideo@server-dev4:/var/medias|⇒  

⇒ ls -lt env_14/medias_union/prod/observer/srv01/var/uploads
juil. 30 16:14 55ba31301dd84.pdf
juil. 24 10:12 55b1f36792b81.pdf
juil. 24 09:50 55b1ee2e5a0af.pdf
...

Problematic

When an environment is rebuilt, medias_rw is still the same, so the documents pool is not "Iso Prod"

Solution

- name: Get differences between dedicated copy of docs and the prod ones
  shell: ls -1 /var/medias/env_{{ index }}/medias_rw
  register: medias_rw_contents

- name: Clear differences between dedicated copy of docs and the prod ones
  file: path=/var/medias/env_{{ index }}/medias_rw/{{ item }} state=absent
  with_items: medias_rw_contents.stdout_lines

- name: Mount AUFS union filesystem for dedicated copy of docs over the prod ones
  mount: src="none" name="/var/medias/env_{{ index }}/medias_union" 
         fstype=aufs opts="br:/var/medias/env_{{ index }}/medias_rw=rw:/var/medias/origin/=ro" 
         state=mounted