Marking commands as read-only

Archives Ansible Project
1

Hi,
When a shell command is executed, Ansible consider it as a modifying
action. It’s a sensible default, because it can’t predict the command
output, but I’m wondering if there’s a way to declare a command as
safe/read-only?

2

This already exists to declare that something doesn’t change something.

changed_when: False

If you mean to run it always in check mode, this is:

always_run: True

3

You can use change_when:

example: change_when: False

4

If you are able to predict the output using changed_when with register
can be useful:
For example:
...
register: cmd_result
changed_when: cmd_result.stdout != ""

5

John Jarvis <john@jarv.org> writes:

If you are able to predict the output using changed_when with register
can be useful:
For example:
...
register: cmd_result
changed_when: cmd_result.stdout != ""

I completely missed these options!

Thanks to Michael, Philippe, and John.