Port issue in compose file - scala

Question

I am getting port issue in docker compose.
My compose file is:
version: '3.1'
services:
db:
hostname: postgres
build:
context: .
dockerfile: Dockerfile.postgres
restart: always
ports:
- "5432:5432"
test:
build:
context: ../..
dockerfile: Dockerfile.test
environment:
DB_URL: "jdbc:postgresql://postgres:5432/postgres?user=postgres&password=postgres"
depends_on:
- postgres
My docker file for test is
FROM openjdk:8
RUN \
curl -L -o sbt-1.2.8.deb http://dl.bintray.com/sbt/debian/sbt-1.2.8.deb && \
dpkg -i sbt-1.2.8.deb && \
rm sbt-1.2.8.deb && \
apt-get update && \
apt-get install sbt && \
sbt sbtVersion
ENV WORK_DIR="/test"
USER root
COPY . ${WORK_DIR}/
RUN cd ${WORK_DIR} && \
sbt test
While running it i am getting:
org.postgresql.util.PSQLException: Connection to localhost:5432 refused. Check that the hostname and port are correct and that the postmaster is accepting TCP/IP connections.
TEST_DB_URL is an env variable in application.conf.
I am running the individual commands:
docker compose -f docker-compose.yml up db
It works fine and docker ps show
0.0.0.0:5432->5432/tcp
But when i run docker compose -f docker-compose.yml up test i downloads dependencies and compiles the code and give me Connection to localhost:5432 refused.

Answer 1

Looks like this has nothing to do with connecting to the database, but is a configuration issue. It's using the default from the application.conf instead of using the override from the environment. You could try to narrow it down by simply printing the config in Scala and figuring out why the ConfigFactory doesn't pick up the environment variable.