How do I include a lot of vars into Ansible roles

Question

Considering a play setup like so:

- name: Provision the stage platform
  hosts: my-stage-host
  vars_files:
    - ../../env_vars/base.yml
    - ../../env_vars/stage.yml
  roles:
    - {role: 'some.ThirdpartyRole'}
    - {role: 'My.Role', name: 'app1', somevar: 'var2', dict: {'var1': 'var2'}, list: [{'var1': 'var2'}]}
    - {role: 'My.Role', name: 'app2', somevar: 'var2', dict: {'var1': 'var2'}, list: [{'var1': 'var2'}]}

This setup is fine and all works as expected (though I don't really like the data structure).. the problem is My.Role has a lot of role instance specific variables, lists and dicts etc, which unfortunately cannot be set in defaults/main.yml (As they are specific to the current role instance), and because I want to be able to use this role multiple times on one server I need isolated variables.

in a perfect world, I would be able to..

  roles:
    - My.Role
      include: ../../varsA.yml

Just like with tasks.. but from what I have read so far in the docs and forums, that's not possible...

At the moment I do have my role working with the following not ideal setup:

File: group_vars/my-host.yml

apps:
  name: 'something'
  someList:
    - item
    ...
  someDict:
    item: item
    itemsList: 
      - item
      ...
  name: 'somethingElse'
  someList:
    - item
    ...
  someDict:
    item: item
    itemsList: 
      - item
      ...

File: playbooks/my-play.yml

  ...
  roles:
    - some.ThirdpartyRole
    - My.Role

As you can see it takes all its vars from a dict defined in my group_vars, and each task within the role uses with_items: myDict, this makes sublists (amongst other things) a bit of a nightmare, something like:

with_subelements:
  - myDict
  - subList

And I cant check for the existence of mydict.subList, I instead need empty vars defined everywhere.

I hope I've explained myself properly, I wondered if anybody had any experience with using a lot of vars in a role that they need to use multiple times in a play, or any other pointers on role/var layout.

Answer 1

I have come up with a solution, it's not necessarily the "Ansible" way, but until an include directive is allowed for roles (as it is for tasks), this appears to be the cleanest way.

Playbook.yml

- name: My Play
  hosts: my-host
  roles:
    - {"role": My.role, "vars_file": "../../vars/projectA.yml"}
    - {"role": My.role, "vars_file": "../../vars/projectB.yml"}

My.role/tasks/main.yml

- name: Load in project specific vars
  include_vars: "{{ vars_file }}"
  ...

Include vars on ansible

I saw a recent issue on Ansibles Github that may affect this solution, I'm going to see if it is still the case, ill try and add to my answer once I've given things a try.