After breaking my install of MySQL last year by trying to move from MariaDB to MySQL as I wanted to try JSON support out, I set out to find a better way of developing my Rails apps, instead of resorting to using something like Vagrant which would create separate VMs for each project.
Running Rails apps inside of Docker can be slow and cumbersome, so I found a way which I think is a better way; Running the databases in Docker instead.
I develop and maintain a number of Rails apps, ranging in Ruby and Rails versions. This means that some older Rails versions may not work properly with the new versions of MySQL or MariaDB.
To solve this, I’m now running my databases inside Docker.
This is an example
docker-compose.dev.yml file for one of my apps.
version: "3.8" services: mysql: container_name: florencebot-mysql image: mysql:8 volumes: - mysql-data:/var/lib/mysql environment: - MYSQL_ROOT_PASSWORD=root - MYSQL_DATABASE=app redis: container_name: florencebot-redis image: "redis:6.2-alpine" volumes: - redis-data:/var/lib/redis volumes: mysql-data: driver: local redis-data: driver: local
I have an alias setup in my ZSH file for running this Docker Compose file in 1 command:
alias dcdev="docker compose -f docker-compose.dev.yml up"
I then use
.env files with the
dotenv-rails gem loaded in development
and test environments to set the required env variables:
You may see that I’m using hostnames here. I’m using a Docker container
called docker-hoster to set these in the hosts file. I have a docker-compose.yml
/opt with the following contents:
--- version: "3.4" services: hoster: image: dvdarias/docker-hoster container_name: hoster restart: always volumes: - /var/run/docker.sock:/tmp/docker.sock - /etc/hosts:/tmp/hosts
This runs all the time so whenever I’m running multiple databases, it automatically adds the required IP to the hosts file.
This setup works really well for me and I hope it helps others.