Ansible. Updating the hostvars variable - ansible

Question

If, during the execution of the playbook, we change the host file in host_vars (i.e. add a new variable), how then can we get this variable in hostvars in the current execution of the playbook? When you run it again, it appears in hostvars.
UPDATE 01:
Here's an example, it doesn't work (
The task Debug 3 should display test_1 instead of VARIABLE IS NOT DEFINED!
- name: Test
hosts: mon
tasks:
- name: Debug 1
debug:
var: hostvars.mon.test_1
- name: Add vars for host_vars
delegate_to: 127.0.0.1
blockinfile:
path: "{{ inventory_dir }}/host_vars/{{ inventory_hostname }}.yml"
marker: "# {mark}: {{ item.key }}"
block: |
{{ item.key }}: {{ item.value }}
with_dict:
- {test_1: "test_1"}
- name: Debug 2
debug:
var: hostvars.mon.test_1
- name: Clear facts
meta: clear_facts
- name: Refresh inventory
meta: refresh_inventory
- name: Setup
setup:
- name: Debug 3
debug:
var: hostvars.mon.test_1
Result:
PLAY [Test] ********************************************************************
TASK [Gathering Facts] *********************************************************
ok: [mon]
TASK [Debug 1] *****************************************************************
ok: [mon] => {
"hostvars.mon.test_1": "VARIABLE IS NOT DEFINED!"
}
TASK [Add vars for host_vars] **************************************************
changed: [mon -> 127.0.0.1] => (item={'key': 'test_1', 'value': 'test_1'})
TASK [Debug 2] *****************************************************************
ok: [mon] => {
"hostvars.mon.test_1": "VARIABLE IS NOT DEFINED!"
}
TASK [Setup] *******************************************************************
ok: [mon]
TASK [Debug 3] *****************************************************************
ok: [mon] => {
"hostvars.mon.test_1": "VARIABLE IS NOT DEFINED!"
}
PLAY RECAP *********************************************************************
mon : ok=6 changed=1 unreachable=0 failed=0 skipped=0 rescued=0 ignored=0
On restart:
PLAY [Test] ********************************************************************
TASK [Gathering Facts] *********************************************************
ok: [mon]
TASK [Debug 1] *****************************************************************
ok: [mon] => {
"hostvars.mon.test_1": "test_1"
}
TASK [Add vars for host_vars] **************************************************
ok: [mon -> 127.0.0.1] => (item={'key': 'test_1', 'value': 'test_1'})
TASK [Debug 2] *****************************************************************
ok: [mon] => {
"hostvars.mon.test_1": "test_1"
}
TASK [Setup] *******************************************************************
ok: [mon]
TASK [Debug 3] *****************************************************************
ok: [mon] => {
"hostvars.mon.test_1": "test_1"
}
PLAY RECAP *********************************************************************
mon : ok=6 changed=0 unreachable=0 failed=0 skipped=0 rescued=0 ignored=0
Maybe there is a way to change hostvars manually in the process?

Answer 1

You can ask Ansible to reread inventory (including host_vars). Generally I'd say that changing inventory on-fly is a code smell, but there are few valid cases.
- name: Refreshing inventory, SO copypaste
meta: refresh_inventory