System variables and psql?

Question

PostgreSQL

Hello. But don’t tell me about psql and docker, for some reason psql doesn’t want to see system variables at all, they are thrown into the image, but psql itself doesn’t use them, for example, I wanted not to enter a password, set it to a variable, but it doesn’t work that way. I experimented a little, I realized that he does not take system variables at all, for example `POSTGRES_USER, POSTGRES_DB`

docker run --rm --name psql --env POSTGRES_PASSWORD=*** --network=host postgres:10.3 \
  psql --echo-all --username=postgres --host=localhost --port=5432 --dbname=medb

Please tell me how to fix this, thanks.