role dependencies, with variables as arguments, called from multiple roles

[Robb Wagoner]

I'd like for roles which configure Node apps, to generate some snippets for an HAProxy config. I'd like to be able to call the same role dependency, app_snippet, in a generalized way, across many apps (app1, app2, etc.). However, the dependency executes once, even though I am using the allow_duplicates: yes in the meta/main.yml for each app. 

In short, I'd like role app_snippet to be completely data-driven and called as a dependency of each app, and executed once for each app, using vars from the calling app role.

Am I missing something fundamental with Variable scoping? Or is this an anti-pattern in Ansible? The allow_duplicates: yes boolean seems to only be in the scope of the calling app role, not global across roles.

PLAYBOOK: apps.yml

- name: install apps

  hosts: webservers

  roles:

    - { role: app1 }

    - { role: app2 }

ROLES:

roles/app1/

roles/app2/

roles/app_snippet/

ROLE appN: (i.e. app1 and app2 are mostly the same, for the purposes of role dependency)

roles/appN/vars/main.yml

---

app: appN

install_dir: /opt/{{app}}

roles/appN/meta/main.yml

---

allow_duplicates: yes

dependencies:

  - { role: app_snippet }

roles/app_snippet/tasks/main.yml

---

- name: HAProxy Backend Snippet {{app}}

  template: src=haproxy_backend.cfg.j2 dest=/etc/haproxy/conf/backend.d/{{app}}.cfg

I only see the task app_snippet | HAProxy Backend Snippet app1 execute. I don't see it execute for app2. 

The same is true (runs once) if I assign a static parameter to the app_snippet role dependency for each app:

roles/app1/meta/main.yml

---

allow_duplicates: yes

dependencies:

  - { role: app_snippet, app: app1 }

roles/app2/meta/main.yml

---

allow_duplicates: yes

dependencies:

  - { role: app_snippet, app: app2 }

This suggests that it is not a variable scoping issue. But it does suggest that late interpolation of variables causes the app_snippet tasks in both calls to be considered "the same", and subsequently executed once.

Any help/pointers are appreciated! Thanks!

Robb

[James Morgan]

Hi,

I'm seeing the same problem and have a very similar use case.

allow_duplicates = yes doesn't seem to be working as I would expect. Unsure if its a bug or I have misunderstood how it works

James