Connection refused to Postgresql on docker - python-3.x

Question

I'm trying to connect to postgres docker container via psycopg2, but i keep getting the same error.
I'm doing this on jupyter (docker container), i restart several times postgres container and i change postgresql.config listen_addresses = '*' to listen_addresses = 'localhost' and it's the same error.
This is the docker run command:
docker run --name postgres -e POSTGRES_PASSWORD=xxxxxxx -d -p 5432:5432 -v $HOME/docker/volumes/postgres:/var/lib/postgresql/data postgres
python
import psycopg2 as pg
connection = pg.connect("host=localhost dbname=easy_cleaning user=root")
I expect to connect, but i got this error:
----> 3 connection = pg.connect("host=localhost dbname=easy_cleaning user=root")
/opt/conda/lib/python3.7/site-packages/psycopg2/__init__.py in connect(dsn, connection_factory, cursor_factory, **kwargs)
124
125 dsn = _ext.make_dsn(dsn, **kwargs)
--> 126 conn = _connect(dsn, connection_factory=connection_factory, **kwasync)
127 if cursor_factory is not None:
128 conn.cursor_factory = cursor_factory
OperationalError: could not connect to server: Connection refused
Is the server running on host "localhost" (127.0.0.1) and accepting
TCP/IP connections on port 5432?
could not connect to server: Cannot assign requested address
Is the server running on host "localhost" (::1) and accepting
TCP/IP connections on port 5432?

Answer 1

On your configuration, your container is not on localhost, Docker created a private IP to it. So you need to run:
docker inspect postgres
And look for IPAddress field to use in your connection as:
connection = pg.connect("host=<DOCKER_IP_ADDRESS> dbname=easy_cleaning user=root")
OR
You can use docker-compose to run your images as services and each service has it's name, which can be used as a hostname in your connections, like:
connection = pg.connect("host=postgres dbname=easy_cleaning user=root")
Read more here