I am successfully able to connect the servicebot service to the postgresql running within the docker container but I want to connect the servicebot to the postgresql running in instance ie not inside docker container. 

I have installed the postgresql successfully. I have set the environment variables related to postgrsql in the docker-compose.yml as bellow. How can I make the docker-compose.yml connect to the 

**docker-compose.yml**

```
version: '2'
services:
  servicebot:
    image: servicebot/servicebot
    environment:
      POSTGRES_DB_PORT : "5432"
      POSTGRES_DB_HOST : "localhost"
      POSTGRES_DB_USER : "servicebot_user"
      POSTGRES_DB_PASSWORD : "servicebot_pass"
      POSTGRES_DB_NAME : "servicebot_user"
      PORT : "3000"
    volumes:
      - upload-data:/usr/src/app/uploads
      - environment-file:/usr/src/app/env
      - db-data:/var/lib/postgresql/data
#    links:
#      - db
    ports:
      - "80:3000"
      - "443:3001"
    command: ["sh", "-c", "node /usr/src/app/bin/wait-for-it.js db 5432  && npm run-script start"]

volumes:
  upload-data:
  environment-file:
  db-data:

```

Previously I had a service named db for postgresql and connected to it with links as you can see, I have commented that out now.

I am very new to postgresql and not able to figure out the right way. I have tried few ways but nothing came to my success. 

**Tried:**

* Adding `extra_hosts` to the ip if the instance
* Adding `host.docker.internal` instead of localhost

**Error Logs:**

> 
> On `docker logs servicename` It does not show anything. The service
>  stops after 29 30 seconds.
> 
> 
>