Show disk space and warn about disk full in Ansible

gistfile1.txt

- name: show disk space                                                                                                                         
  debug: msg="{{ ((mount.size_total - mount.size_available) / 1000000000) |  round(1,'common') }}GB of {{ (mount.size_total / 1000000000)|round(
1, 'common') }}GB ({{ (100 * ( (mount.size_total - mount.size_available) / mount.size_available)) | round(1, 'common')}}%)"                     
  vars:                                                                                                                                         
    mount: "{{ ansible_mounts | first }}"                                                                                                       
  tags: disk                                                                                                                                    
                                                                                                                                                
- name: ensure at least 20% free                                                                                               
  assert:                                                                                                                                       
    that: mount.size_available > mount.size_total|float * 0.2                                                                         
    msg: Disk space is near full!                                                                         
  vars:                                                                                                                                         
    mount: "{{ ansible_mounts | first }}"