Is it possible to use variables of "list" type from inventory within Jinja templates (typecast)?

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1

Hi,

in our inventory we use variables of type "list" like

   userlist = "['alice', 'bob', 'mallory']"

which - e.g. - we use in loops within tasks to roll out public SSH keys:

   - name: Roll out SSH keys for someotheruser
     authorized_key:
       user: someotheruser
       manage_dir: yes
       exclusive: no
       key: "{{ lookup('file', 'vars/ssh-keys/'+item+'.pub') }}"
     with_items: "{{ userlist }}"

This has some unwanted side-effects. Therefore we'd like to construct the full authorized_keys from a template and copy the resulting file:

   - name: Roll out SSH keys for someotheruser
     template:
       src: authorized_keys.j2
       dest: /home/someotheruser/.ssh/authorized_keys
       owner: someotheruser
       group: someothergroup
       mode: 0600
       force: yes

authorized_keys.j2:

   # Managed by ansible, do not modify

   {% for user in userlist %}
   {{ lookup('file', 'vars/ssh-keys/'+user+'.pub') }}
   {% endfor %}

This results in jinja seeing each single character of the variable "userlist" as a key and hence looks for the files "vars/ssh-keys/[.pub", "vars/ssh-keys/'.pub", "vars/ssh-keys/a.pub" ecc. ecc.

Is there a way to tell Jinja, that these variables are in fact lists? Like some kind of typecasting?

I am aware, that "Values [...] are [...] interpreted [...] as a string" (https://docs.ansible.com/ansible/latest/user_guide/intro_inventory.html). However we'd like to avoid separate host and group variable files, as they make the setup confusing.

Cheers
frank

2

This must be a bug because it work if you have the variable on the host like so

host1 userlist="['alice', 'bob', 'mallory']"

But if you add it to a group like so it fails

host1
[all:vars]
userlist="['alice', 'bob', 'mallory']"

A workaround you could do before you use the variable is

- set_fact:
     userlist: '{{ userlist }}'