ansible with_items list of lists is flattening

Question

I'm trying to use ansible to loop over a list of lists to install some packages. But {{item}} is returning every element in the sub lists rather than the sublist itself. I have a yaml file which come from a manifest list from outside ansible and it looks like this:

---
modules:
 - ['module','version','extra']
 - ['module2','version','extra']
 - ['module3','version','extra']

My task looks like this:

task:
 - include_vars: /path/to/external/file.yml
 - name: install modules
   yum: name={{item.0}} state=installed
   with_items: "{{ modules }}"

When I run that I get:

fatal: [localhost]: FAILED! => {"failed": true, "msg": "ERROR! int object has no element 0"}

When I try:

- debug: msg="{{item}}"
  with_items: "{{module}}"

it prints every element (module, version, extra, and so on), not just the sublist (which is what I would expect)

Answer 1

An alternative way to solve this issue is to use a complex item instead of a list of list. Structure your variables like this:

- modules:
  - {name: module1, version: version1, info: extra1}
  - {name: module2, version: version2, info: extra2}
  - {name: module3, version: version3, info: extra3}

Then you can still use with_items, like this:

- name: Printing Stuffs...
  shell: echo This is "{{ item.name }}", "{{ item.version }}" and "{{ item.info }}"
  with_items: "{{modules}}"