Ansible is a great automation solution. I mainly use it to provision servers and launch Docker instances on them. Sometimes I need container attributes, like PID or Port to configure Nginx or monitoring tools.
While the Ansible documentation gives you some hints, I didn’t find it 100% obvious on how to solve this. Basically all your newly-created containers will end up in a list called docker_containers. It has the same structure as docker inspect.
For the PID:
For the host port:
So you could add a PID-file for a container like this:
Also read the full docs here.