How can I show progress for a long-running Ansible task?

I came across this problem today on OSX, where I was running a docker shell command which took a long time to build and there was no output whilst it built. It was very frustrating to not understand whether the command had hung or was just progressing slowly.

I decided to pipe the output (and error) of the shell command to a port, which could then be listened to via netcat in a separate terminal.

myplaybook.yml

- name: run some long-running task and pipe to a port
  shell: myLongRunningApp > /dev/tcp/localhost/4000 2>&1

And in a separate terminal window:

$ nc -lk 4000
Output from my
long
running
app will appear here

Note that I pipe the error output to the same port; I could as easily pipe to a different port.

Also, I ended up setting a variable called nc_port which will allow for changing the port in case that port is in use. The ansible task then looks like:

  shell: myLongRunningApp > /dev/tcp/localhost/{{nc_port}} 2>&1

Note that the command myLongRunningApp is being executed on localhost (i.e. that’s the host set in the inventory) which is why I listen to localhost with nc.