Ansible display realtime shell stdout

Question

I want see the realtime shell stdout, instead of registering in a variable and then display once it is completed.

Example Playbook - test.yml

- name: Testing RUN Shell Command
  hosts: localhost
  connection: local

  tasks:
  - name: Runnig Update
    shell: apt update

Default Output

$ ansible-playbook  test.yml 

PLAY [Testing RUN Shell Command] ******************************************************************************************************

TASK [Gathering Facts] ****************************************************************************************************************
ok: [localhost]

TASK [Runnig Update] ******************************************************************************************************************
changed: [localhost]

PLAY RECAP ****************************************************************************************************************************
localhost                  : ok=2    changed=1    unreachable=0    failed=0   

But I want to see what it is doing like when we run the apt update in terminal

$ sudo apt update
Ign:1 http://dl.google.com/linux/chrome/deb stable InRelease
Hit:2 http://dl.google.com/linux/chrome/deb stable Release                                                                            
Hit:3 http://ppa.launchpad.net/brightbox/ruby-ng/ubuntu bionic InRelease                                                              
Get:4 http://security.ubuntu.com/ubuntu bionic-security InRelease [88.7 kB]                                                           
Hit:6 http://in.archive.ubuntu.com/ubuntu bionic InRelease                                                                            
Hit:7 http://ppa.launchpad.net/canonical-chromium-builds/stage/ubuntu bionic InRelease                                                
------OUTPUT REMOVED----------

I see that there is already discussion going on at github issue and look like that is not possible.

Is there any trick get the realtime stdout with help ansible Callback?

Solution

"Real time" or "streaming" output has not been merged to Ansible yet. The original issue was closed in 2014 as not feasible. A more recent proposal has no major updates since February 2018.

This is not available for users of Ansible. It will require serious hacking, and more importantly testing, on command and callback plugins to work as proposed.

---

Bonus playbook review: Your example command can be done by the apt module. This has more features than calling apt command line yourself.

- name: Only run "apt-get update" if the last one is more than 3600 seconds ago
  apt:
    update_cache: yes
    cache_valid_time: 3600