Connection refused : mariaDB on a webapp running on Jetty on docker-compose-CodePudding

I have to deploy a web app with a Jetty Server. This app need a database, running on MariaDB. Here the docker-compose file used to deploy the app:

version: '3.0'

services:

  jetty:
    build:
      context: .
      dockerfile: docker/jetty/Dockerfile
    container_name: app-jetty
    ports:
      - "8080:8080"
    depends_on:
      - mariadb
    networks:
      - app
    links:
      - "mariadb:mariadb"

  mariadb:
    image: mariadb:10.7
    container_name: app-mariadb
    restart: always
    environment:
      MARIADB_ROOT_PASSWORD: myPassword
      MARIADB_DATABASE: APPBD
    ports:
      - "3307:3306"
    networks:
      - app
  
  adminer:
    image: adminer
    container_name: app-adminer
    restart: always
    ports:
      - "2002:8080"
    depends_on:
      - mariadb
    networks:
      - app

networks:
  app:
    driver: bridge

The Dockerfile used by the Jetty container:

FROM gradle:7.2-jdk17 as grad

WORKDIR /tmp
RUN mkdir src
RUN ls -la
COPY src /tmp/src
COPY build.gradle /tmp/build.gradle
RUN ls -la
RUN gradle --warning-mode all war
RUN ls -la /tmp/build/libs/

FROM jetty:latest
COPY --from=grad /tmp/build/libs/tmp.war /var/lib/jetty/webapps/ROOT.war
EXPOSE 8080

The app is build with Gradle before the initialisation of Jetty.

The problem is the database: it takes several minutes to initialize the MariaDB database. So, when I want to connect to the DB from Adminer, I have to wait until the DB is ready before I can log in. But for my app, I got this: Could not connect to address=(host=mariadb)(port=3306)(type=master) : Socket fail to connect to host:mariadb, port:3306. Connection refused, even if the database is ready. I have to stop the app-jetty container and restart it to use the database. I thought that depends_on will ran the app-jetty when the database was ready, but it ran the container when the app-mariadb was ran.

I use JDBC to establish connection to the DB : jdbc:mariadb://mariadb:3306/APPBD?user=root&password=myPassword. I successfully establish connection on local execution with gradle appRun and use localhost:3306 instead of mariadb:3306, so I think I don't have any mistakes on my code.

How can I indicate to the app-jetty container to start only when MariaDB is ready?

CodePudding user response：

Compose (2.1) supports healthchecks:

Under the mariadb service:

    healthcheck:
        test: [ "CMD", "mariadb-admin", "--protocol", "tcp" ,"ping" ]
        timeout: 3m
        interval: 10s
        retries: 10

ref: tip.