How do I apply an Ansible with_items loop to the included tasks?

Question

The documentation for import_tasks mentions

Any loops, conditionals and most other keywords will be applied to the included tasks, not to this statement itself.

This is exactly what I want. Unfortunately, when I attempt to make import_tasks work with a loop

- import_tasks: msg.yml
  with_items:
    - 1
    - 2
    - 3

I get the message

ERROR! You cannot use loops on 'import_tasks' statements. You should use 'include_tasks' instead.

I don't want the include_tasks behaviour, as this applies the loop to the included file, and duplicates the tasks. I specifically want to run the first task for each loop variable (as one task with the standard with_items output), then the second, and so on. How can I get this behaviour?

---

Specifically, consider the following:

Suppose I have the following files:

playbook.yml

---                       

- hosts: 192.168.33.100
  gather_facts: no
  tasks:
  - include_tasks: msg.yml
    with_items:
      - 1
      - 2

msg.yml

---

- name: Message 1
  debug:
    msg: "Message 1: {{ item }}"

- name: Message 2
  debug:
    msg: "Message 2: {{ item }}"

I would like the printed messages to be

Message 1: 1
Message 1: 2
Message 2: 1
Message 2: 2

However, with import_tasks I get an error, and with include_tasks I get

Message 1: 1
Message 2: 1
Message 1: 2
Message 2: 2

Answer 1

You can add a with_items loop taking a list to every task in the imported file, and call import_tasks with a variable which you pass to the inner with_items loop. This moves the handling of the loops to the imported file, and requires duplication of the loop on all tasks.

---

Given your example, this would change the files to:

playbook.yml

---

- hosts: 192.168.33.100
  gather_facts: no
  tasks:
  - import_tasks: msg.yml
    vars:
      messages:
        - 1
        - 2

msg.yml

---

- name: Message 1
  debug:
    msg: "Message 1: {{ item }}"
  with_items:
    - "{{ messages }}"

- name: Message 2
  debug:
    msg: "Message 2: {{ item }}"
  with_items:
    - "{{ messages }}"