Shows how to create a docker mongo status checker and run command after it connects successfully

mongo-status-checker.docker-compose.yml

version: '3.0'
services:
  mongo:
    image: mongo
    ports:
     - "27017:27017"
     - "28017:28017"
    environment:
     MONGO_INITDB_ROOT_USERNAME: mongoadmin
     MONGO_INITDB_ROOT_PASSWORD: secret
  mongo-config:
    image: mongo
    depends_on:
     - mongo
    command: >
      /bin/bash -c "
        until mongo --host mongo -u mongoadmin -p secret --authenticationDatabase admin --eval \"printjson(db.serverStatus())\"
        do
          echo sleeping;
          sleep 3;
        done;
        echo Successfully Connected, running Mongo config commands.;
        mongo --host mongo -u mongoadmin -p secret --authenticationDatabase admin mymongodb --eval 'db.createUser({ \"user\": \"mongouser\", \"pwd\": \"secret\", \"roles\": [ \"readWrite\", \"dbAdmin\" ] })';
      "

I am trying a similar thing, it says unknown host mongo