Is there a standard/prefered method for debug logging in a custom Ansible module.

Question

I would like to add debug logging to my custom Ansible module such that when the -vvv option is supplied to the ansible-playbook command I see the log messages but otherwise do not. I don't want the results of the module to be affected by this logging. In other words, I don't want to write the log messages to stdout or stderr directly.

Answer 1

Modules normally are executed remotely, so there actually is no way to directly output anything.

You can return additional data in your module in the exit_json call.

if module._verbosity >= 3:
    module.exit_json(changed=True, debug="wooha!")
else:
    module.exit_json(changed=True)

module._verbosity corresponds to the verbosity level (-v = 1, -vvv = 3) and is available since Ansible 2.1.

Source: Ansible Devel-list and github