How to connect locally hosted MySQL database with the docker container

Through docker-compose.yml I am able to run the application. Now we want to move the application to production, But we don't want to use the container database. So is there any way so that I can connect my local MySQL database with the application using docker-compose?

My docker-compose.yml looks like:

version: '3'
services:
  web-app:
    build:
      context: .
      dockerfile: web-app/Dockerfile
    ports:
      - 8080:8080
    links:
      - app-db

  app-db:
    build:
      context: .
      dockerfile: app-db/Dockerfile

    environment:
    - MYSQL_ROOT_PASSWORD=password
    - MYSQL_DATABASE=Optimize
    ports:
      - 3306:3306

Instead of app-db part I just want to connect to my locally hosted mysql database.

Solution

Find the host machine ip in the docker network. If you use docker-compose.yml version: "3" it's probably that that IP is: 172.18.0.1, but confirm it searching for the "Gateway" of your container (your host):

docker inspect <container-id-or-name> | grep Gateway
"Gateway": "",
            "IPv6Gateway": "",
            "Gateway": "172.18.0.1",
            "IPv6Gateway": "",

So inside your docker application point to MySQL as this: 172.18.0.1:3306 (maybe in a configuration file). Take into account that that IP is fixed as long as the docker network still the same (the network is created by docker-compose, and it is not removed unless you do docker-compose down)

Also, check that your MySQL is listening to all of its interfaces. In your my.cnf search for bind-address that should be 0.0.0.0 (consider security issues if your server has public IP).

As an alternative you can bring to the container the same networking as your host, in order to share the localhost, so the container will find mysql there. Use network mode as "host":

version: '3'
services:
  web-app:
    build:
      context: .
      dockerfile: web-app/Dockerfile
    ports:
       - 8080:8080
    network_mode: "host"

Then, point in your hibernate.properties to mysql as this: localhost:3306