Accessing postgres data in docker-compose network - postgresql

Question

I'm having trouble accessing a database created from a docker-compose file.
Given the following compose file, I should be able to connect to it from java using something like:
jdbc:postgresql://eprase:eprase#database:7000/eprase
However, the connection is rejected. I can't even use PGAdmin to connect it using the same details to create a new server.
I've entered the database container and ran psql commands to verify that the eprase user and database have been created according to postgres Docker documentation, everything seems fine. I can't tell if the problem is within the database container or something I need to change in the compose network.
The client & server services can largely be ignored, the server is a java based web API and the client is an Angular app.
Compose file:
version: "3"
services:
client:
image: eprase/client:latest
build: ./client/eprase-app
networks:
api:
ports:
- "5000:80"
tty: true
depends_on:
- server
server:
image: eprase/server:latest
build: ./server
networks:
api:
ports:
- "6000:8080"
depends_on:
- database
database:
image: postgres:9
volumes:
- "./database/data:/var/lib/postgresql/data"
environment:
- "POSTGRES_USER=eprase"
- "POSTGRES_PASSWORD=eprase"
- "POSTGRES_DB=eprase"
networks:
api:
ports:
- "7000:5432"
restart: unless-stopped
pgadmin:
image: dpage/pgadmin4:latest
environment:
- "PGADMIN_DEFAULT_EMAIL=admin#eprase.com"
- "PGADMIN_DEFAULT_PASSWORD=eprase"
networks:
api:
ports:
- "8000:80"
depends_on:
- database
networks:
api:

Answer 1

The PostgreSQL database is listening on container port 5432. The 7000:5432 line is mapping host port 7000 to container port 5432. That allows you to connect to the database on port 7000. But, your services on a common network (api) should communicate with each other via the container ports.
So, from the perspective of the containers for the client and server services, the connection string should be:
jdbc:postgresql://eprase:eprase#database:5432/eprase