i have a strange behaviour that i don't understand
Playbook "vars_roles.yml":
---
- hosts: localhost
gather_facts: no
vars:
msg_role3: "first_run"
roles:
- role: role3
- hosts: localhost
gather_facts: no
vars:
msg_role3: "second_run"
roles:
- role: role3
Content of role3 :
cat roles/role3/defaults/main.yml
---
# defaults file for role3
add_value: false
msg_role3: "default"
tab_msg:
- "Init value: {{ msg_role3 }}"
cat roles/role3/tasks/main.yml
---
# tasks file for role3
- name: Value
debug:
msg: "Variable is {{ msg_role3 }}"
- name: Content of Array
debug:
var: tab_msg
- name: Add "value" into Array
set_fact:
tab_msg: "{{ (tab_msg) + [item] }}"
loop:
- "value: {{ msg_role3 }}"
when: add_value | bool
- name: Content of Array after add value
debug:
var: tab_msg
So, my problem came from the set_fact with the list 'tab_msg: "{{ (tab_msg) + [item] }}"' if this task is played, the list "tab_msg" keep values from the first run of the role "role3"
Example without the set_fact :
ansible-playbook vars_roles.yml -e add_value=false
[WARNING]: provided hosts list is empty, only localhost is available. Note that the implicit localhost does not match 'all'
PLAY [localhost] ******************************************************************************************************************************************************
TASK [role3 : Value] **************************************************************************************************************************************************
Tuesday 27 October 2020 16:28:59 +0100 (0:00:00.055) 0:00:00.055 *******
ok: [localhost] => {
"msg": "Variable is first_run"
}
TASK [role3 : Content of Array] ***************************************************************************************************************************************
Tuesday 27 October 2020 16:28:59 +0100 (0:00:00.053) 0:00:00.108 *******
ok: [localhost] => {
"tab_msg": [
"Init value: first_run"
]
}
TASK [role3 : Add "value" into Array] *********************************************************************************************************************************
Tuesday 27 October 2020 16:28:59 +0100 (0:00:00.052) 0:00:00.161 *******
skipping: [localhost] => (item=value: first_run)
TASK [role3 : Content of Array after add value] ***********************************************************************************************************************
Tuesday 27 October 2020 16:28:59 +0100 (0:00:00.052) 0:00:00.214 *******
ok: [localhost] => {
"tab_msg": [
"Init value: first_run"
]
}
PLAY [localhost] ******************************************************************************************************************************************************
TASK [role3 : Value] **************************************************************************************************************************************************
Tuesday 27 October 2020 16:28:59 +0100 (0:00:00.058) 0:00:00.272 *******
ok: [localhost] => {
"msg": "Variable is second_run"
}
TASK [role3 : Content of Array] ***************************************************************************************************************************************
Tuesday 27 October 2020 16:28:59 +0100 (0:00:00.047) 0:00:00.319 *******
ok: [localhost] => {
"tab_msg": [
"Init value: second_run"
]
}
TASK [role3 : Add "value" into Array] *********************************************************************************************************************************
Tuesday 27 October 2020 16:28:59 +0100 (0:00:00.048) 0:00:00.368 *******
skipping: [localhost] => (item=value: second_run)
TASK [role3 : Content of Array after add value] ***********************************************************************************************************************
Tuesday 27 October 2020 16:28:59 +0100 (0:00:00.052) 0:00:00.420 *******
ok: [localhost] => {
"tab_msg": [
"Init value: second_run"
]
}
PLAY RECAP ************************************************************************************************************************************************************
localhost : ok=6 changed=0 unreachable=0 failed=0 skipped=2 rescued=0 ignored=0
Example with set_fact played :
ansible-playbook vars_roles.yml -e add_value=true
[WARNING]: provided hosts list is empty, only localhost is available. Note that the implicit localhost does not match 'all'
PLAY [localhost] ******************************************************************************************************************************************************
TASK [role3 : Value] **************************************************************************************************************************************************
Tuesday 27 October 2020 16:31:44 +0100 (0:00:00.052) 0:00:00.052 *******
ok: [localhost] => {
"msg": "Variable is first_run"
}
TASK [role3 : Content of Array] ***************************************************************************************************************************************
Tuesday 27 October 2020 16:31:44 +0100 (0:00:00.052) 0:00:00.104 *******
ok: [localhost] => {
"tab_msg": [
"Init value: first_run"
]
}
TASK [role3 : Add "value" into Array] *********************************************************************************************************************************
Tuesday 27 October 2020 16:31:44 +0100 (0:00:00.049) 0:00:00.154 *******
ok: [localhost] => (item=value: first_run)
TASK [role3 : Content of Array after add value] ***********************************************************************************************************************
Tuesday 27 October 2020 16:31:44 +0100 (0:00:00.054) 0:00:00.208 *******
ok: [localhost] => {
"tab_msg": [
"Init value: first_run",
"value: first_run"
]
}
PLAY [localhost] ******************************************************************************************************************************************************
TASK [role3 : Value] **************************************************************************************************************************************************
Tuesday 27 October 2020 16:31:44 +0100 (0:00:00.053) 0:00:00.262 *******
ok: [localhost] => {
"msg": "Variable is second_run"
}
TASK [role3 : Content of Array] ***************************************************************************************************************************************
Tuesday 27 October 2020 16:31:44 +0100 (0:00:00.047) 0:00:00.309 *******
ok: [localhost] => {
"tab_msg": [
"Init value: first_run",
"value: first_run"
]
}
TASK [role3 : Add "value" into Array] *********************************************************************************************************************************
Tuesday 27 October 2020 16:31:44 +0100 (0:00:00.047) 0:00:00.357 *******
ok: [localhost] => (item=value: second_run)
TASK [role3 : Content of Array after add value] ***********************************************************************************************************************
Tuesday 27 October 2020 16:31:44 +0100 (0:00:00.055) 0:00:00.412 *******
ok: [localhost] => {
"tab_msg": [
"Init value: first_run",
"value: first_run",
"value: second_run"
]
}
PLAY RECAP ************************************************************************************************************************************************************
localhost : ok=8 changed=0 unreachable=0 failed=0 skipped=0 rescued=0 ignored=0
Any ideas ?
Thanks
The result, you see, is correct. See Understanding variable precedence. Value assigned in set_fact has higher precedence (19.) than role's defaults (2.). In addition to this, the value assigned in set_fact will be available to subsequent plays during an ansible-playbook run.
In the simplified example below, set_fact (19.) has higher precedence than play vars (12.)
shell> cat pb.yml
- hosts: localhost
vars:
msg_role3: "first_run"
tasks:
- debug:
var: msg_role3
- set_fact:
msg_role3: "Added value"
when: add_value|default(false)|bool
- hosts: localhost
vars:
msg_role3: "second_run"
tasks:
- debug:
var: msg_role3
gives (abridged)
shell> ansible-playbook pb.yml
PLAY [localhost] ****
msg_role3: first_run
PLAY [localhost] ****
msg_role3: second_run
shell> ansible-playbook pb.yml -e "add_value=true"
PLAY [localhost] ****
msg_role3: first_run
PLAY [localhost] ****
msg_role3: Added value
The solution to your problem is removing tab_msg from defaults/main.yml and putting it into the tasks/main.yml. For example
shell> cat roles/role3/defaults/main.yml
add_value: false
msg_role3: "default"
shell> cat roles/role3/tasks/main.yml
- name: Init tab_msg
set_fact:
tab_msg:
- "Init value: {{ msg_role3 }}"
- name: Value
...