How to deal with multiple when condition for registered variable in ansible - variables

Question

I have a playbook 3 raw task (or more) with sample commands like below:
Playbook mytest.yml
- hosts: remotehost
gather_facts: no
tasks:
- name: Execute command1
raw: "ls -ltr"
register: cmdoutput
when: remcmd == "list"
- name: Execute command2
raw: "hostname"
register: cmdoutput
when: remcmd == "host"
- name: Execute command3
raw: "uptime"
register: cmdoutput
when: remcmd == "up"
- hosts: localhost
gather_facts: no
tasks:
- debug:
msg: "Printing {{ hostvars['remotehost']['cmdoutput'] }}"
This is my nventory myhost.yml
[remotehost]
myserver1
Here is how I run the playbook:
ansible-playbook -i myhost.yml mytest.yml -e remcmd="host"
PLAY [remotehost] ***************************************************************************************************************
TASK [Execute command1] *********************************************************************************************************
Thursday 06 October 2022 07:06:06 -0500 (0:00:00.013) 0:00:00.013 ******
skipping: [myserver1]
TASK [Execute command2] *********************************************************************************************************
Thursday 06 October 2022 07:06:06 -0500 (0:00:00.023) 0:00:00.036 ******
changed: [myserver1]
TASK [Execute command3] *********************************************************************************************************
Thursday 06 October 2022 07:06:06 -0500 (0:00:00.521) 0:00:00.557 ******
skipping: [myserver1]
PLAY [localhost] ****************************************************************************************************************
TASK [debug] ********************************************************************************************************************
Thursday 06 October 2022 07:06:06 -0500 (0:00:00.032) 0:00:00.590 ******
fatal: [localhost]: FAILED! => {"msg": "The task includes an option with an undefined variable. The error was: \"hostvars['remotehost']\" is undefined\n\nThe error appears to be in '/home/wladmin/mytest.yml': line 22, column 7, but may\nbe elsewhere in the file depending on the exact syntax problem.\n\nThe offending line appears to be:\n\n tasks:\n - debug:\n ^ here\n"}
PLAY RECAP **********************************************************************************************************************
localhost : ok=0 changed=0 unreachable=0 failed=1 skipped=0 rescued=0 ignored=0
myserver1 : ok=1 changed=1 unreachable=0 failed=0 skipped=2 rescued=0 ignored=0
My requirement is no matter what value is passed for remcmd my localhost play should print stdoutlines of cmdoutput

Answer 1

Preliminary notes:
Using raw is evil.
Don't use raw unless to install prereqs (i.e. python) on the target host. Then switch to modules or at the very least command/shell
If you still intend to use raw, go back to point 1 above
In case your forgot to go back to point 1: using raw is evil
Don't register several tasks with the same var name (the last one always win, even if skipped). Don't create tasks you can avoid up-start.
As an illustration of the above principles
- hosts: remotehost
gather_facts: no
vars:
cmd_map:
list: ls -ltr
host: hostname
up: uptime
tasks:
- name: Make sure remcmd is known
assert:
that: remcmd in cmp_map.keys()
fail_msg: "remcmd must be one of: {{ cmd_map.keys() | join(', ') }}"
- name: Execute command
command: "{{ cmd_map[remcmd] }}"
register: cmdoutput
- name: Show entire result from above task
debug:
var: cmdoutput

Answer 2

my localhost play should print stdout_lines of cmdoutput
As far as I understand "How the debug module works", it can only print on the Control Node.
Therefore you could just remove three (3) lines in your example
- hosts: localhost
gather_facts: no
tasks:
and give it a try with
- hosts: remotehost
gather_facts: no
tasks:
- name: Execute command1
raw: "ls -ltr"
register: cmdoutput
when: remcmd == "list"
- name: Execute command2
raw: "hostname"
register: cmdoutput
when: remcmd == "host"
- name: Execute command3
raw: "uptime"
register: cmdoutput
when: remcmd == "up"
- debug:
msg: "Printing {{ cmdoutput }}"
and independently of which task became executed the result would be provided.
Apart from the answer about "How the debug module works" here, I like to recommended to proceed further with the answer of Zeitounator, since it will address your possible use case more complete.