DOCKER_Cannot run multiple services by docker-compose - postgresql

Question

I'm set up docker compose for my project with 2 services: spring-boot and postgresql. I created Dockerfile and docker-compose,yml as below:
Dockerfile :
FROM openjdk:8-jdk-alpine
MAINTAINER linhan.com
COPY target/LinhAn-0.0.1-SNAPSHOT.jar linhan-server-1.0.0.jar
ENTRYPOINT ["java","-jar","/linhan-server-1.0.0.jar"]
docker-compose.yml:
version: '2'
services:
spring_boot:
image: 'linhan'
build: .
container_name: api
ports:
- "8080:8080"
depends_on:
- postgres
environment:
- SPRING_DATASOURCE_URL=jdbc:jdbc:postgresql://localhost:5432/test_db
- SPRING_DATASOURCE_USERNAME=user
- SPRING_DATASOURCE_PASSWORD=123456
- SPRING_JPA_HIBERNATE_DDL_AUTO=update
postgres:
image: 'postgres:13.1-alpine'
container_name: db
environment:
- POSTGRES_USER=user
- POSTGRES_PASSWORD=123456
Then, when I type docker-compose up in terminal, postgres ran only, spring boot still not.
I searched google for solution but seems no hope. Please help me, thanks a lot!!!!!

Answer 1

I think you need to change the SPRING_DATASOURCE_URL to reference your service name instead of localhost. The service name is resolved automatically to your service since all services are part of the default_network by default in docker-compose.
- SPRING_DATASOURCE_URL=jdbc:jdbc:postgresql://postgres:5432/test_db
Also, for clarity I would suggest you add the port to your docker-compose postgres service, so it is clear which port is being used, even if it is the default:
postgres:
image: 'postgres:13.1-alpine'
container_name: db
ports:
- "5432"
environment:
- POSTGRES_USER=user
- POSTGRES_PASSWORD=123456
Also, another suggestion would be to try and use a healthcheck to see if your database service becomes available instead of a simple depends_on. The short version will mark the dependency fulfilled as soon as the container is Running, regardless of the availability of the database.
Either that, or you can add application logic to retry database connection in case of failure.