Docker Compose + Spring Boot + Postgres connection
I had the same problem and I lost some time to understand and solve this problem:
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.
I show all the properties so that everyone understands.application.properties:
spring.datasource.url=jdbc:postgresql://localhost:5432/testdb
spring.datasource.driver-class-name=org.postgresql.Driver
spring.datasource.username=postgres
spring.datasource.password=postgres
spring.jpa.properties.hibernate.dialect=org.hibernate.dialect.PostgreSQL82Dialect
spring.jpa.hibernate.ddl-auto=update
docker-compose.yml:
version: "3"
services:
springapp:
build: .
container_name: springapp
environment:
SPRING_DATASOURCE_URL: jdbc:postgresql://db:5432/testdb
ports:
- 8000:8080
restart: always
depends_on:
- db
db:
image: postgres
container_name: db
environment:
- POSTGRES_USER=postgres
- POSTGRES_PASSWORD=postgres
- POSTGRES_DB=testdb
- PGDATA=/var/lib/postgresql/data/pgdata
ports:
- 5000:5432
volumes:
- pgdata:/var/lib/postgresql/data
restart: always
volumes:
pgdata:
For start spring application with local database we use url localhost.
For connect to container with database we need change 'localhost' on your database service, in my case 'localhost' to 'db'.
Solution: add SPRING_DATASOURCE_URL
environment in docker-compose.yml
wich rewrite spring.datasource.url
value for connect:
environment:
SPRING_DATASOURCE_URL: jdbc:postgresql://db:5432/testdb
I hope this helps someone save his time.
Each container has its own network interface with its own localhost. So change how Java points to Postgres:
spring.datasource.url=jdbc:postgresql://localhost:5432/sample
To:
spring.datasource.url=jdbc:postgresql://db:5432/sample
db
will resolve to the proper Postgres IP.
Bonus. With docker-compose you don't need to build your image by hand. So change:
web:
image: myuser/manager:latest
To:
web:
build: .