Use MQTT and Postgres instance of Thingsboard docker

Setup and configuration
1

Hi Gurus,

I got a thingsboards instance working docker-compose working fine. Then on the same server (private) I want to install chirpstack same way, I mean docker-compose. I can change some port to avoid conflict but I would like chirpstack to use MQTT of the thingsboard docker instance

For this I can imagine I just need to remove these lines from chirpstack docker-compose.yml

  mosquitto:
    image: eclipse-mosquitto
    ports:
      - 1883:1883

Now I would like to do the same with postgres, so chirpstack use thingsboard postgres instance, the deal is of course I would like to create postgres database and user for chirpstack into thingsboard docker instance of postgres. File looks to be there chirpstack-docker/configuration/postgresql/initdb/ but I don’t know the thingsboard postgres root password to do that.

But what would the docker-compose.yml file something like that ?

  postgresql:
    environment:
      - POSTGRES_PASSWORD=root

Anyway if someone has a docker-compose.yml file that contains all for thingsboard and chirpstack it would be awesome (I mean not 2 instances of MQTT and postgres of course)