docker compose: spring boot connection to mysql database refused - mysql

Question

I'm pretty new to Docker and I need to startup my Angular/SpringBoot/MySQL project with docker-compose on the docker toolbox. I copied a docker yml file into my project which used the same technologies and changed the paths inside of it to match my project. However when I try docker-compose, it throws the following error:
com.mysql.cj.jdbc.exceptions.CommunicationsException: Communications link failure
[...] 84 common frames omitted
Caused by: java.net.ConnectException: Connection refused (Connection refused)
the docker-compose.yml looks like:
version: '3'
services:
database:
image: mysql
container_name: database
environment:
MYSQL_ROOT_PASSWORD: ****
MYSQL_DATABASE: db_example
MYSQL_USER: springuser
MYSQL_PASSWORD: ****
ports:
- 3306:3306
volumes:
- db_exampleData:/var/lib/mysql
springapi:
image: openjdk:10-jre-slim
container_name: springapi
ports:
- 8443:8443
depends_on:
- database
volumes:
- ./backend/target/backend-0.1.0.jar:/application.jar
command: ["java", "-jar", "application.jar"]
angular:
image: nginx:alpine
container_name: angular
ports:
- 4200:80
depends_on:
- springapi
volumes:
- ./nginx.conf:/etc/nginx/nginx.conf
- ./frontend/my-app/dist/my-app:/usr/share/nginx/html
volumes:
db_exampleData:
the application.properties:
spring.jpa.hibernate.ddl-auto=none
spring.jpa.open-in-view=false
spring.datasource.url=jdbc:mysql://localhost:3306/db_example
spring.datasource.username=springuser
spring.datasource.password=****
server.port=8443
any suggestion would be helpful!

Answer 1

you need to change your connecion like this:
jdbc:mysql://database:3306/db_example
and add this to your docker-compose under springapi service:
links:
- database
on the other hand you may use wait-for-it.sh to check if DB is up by add a command section under springapi service:
command: ["path/to/wait-for-it.sh", "database:3306", "-t", "6000", "--", "YOUR ACTUAL COMMAND"]