Docker: Springboot container can not connect to PostgreSql Container Connection error

Question

I am building my first Springboot 2.0 application. I am trying to put my Springboot application into one docker container and my PostgresDB into another container.

Answer 1

Try with :

spring.datasource.url= jdbc:postgresql://pgdb:5432/java_learning

The postgres database is not running on localhost, it's running in the other container which has an other IP (yet unknown).

Thanksfully, docker-compose automatically create a network shared among all the containers in the docker-compose.yml (unless explicitly said to do not), as a result you can magically use the service name as an hostname.

Also, you have a typo in the port, Postgres use 5432 by default, not 54321