How to determine the Host OS with Ansible?

About

When downloading executable binary, you need to detect the type of OS. This script will show you how to do it in ansible with facts

Script

- name: Set OS variable for Linux
  set_fact:
    host_os: "linux"
  when: ansible_facts['os_family'] == "Debian" or ansible_facts['os_family'] == "RedHat" or ansible_facts['os_family'] == "Suse"

- name: Set OS variable for macOS
  set_fact:
    host_os: "macos"
  when: ansible_facts['os_family'] == "Darwin"

- name: Set OS variable for Windows
  set_fact:
    host_os: "windows"
  when: ansible_facts['os_family'] == "Windows"