A mini-starter Rails 7.0.6 web application

• Devise authentication with DaisyUI forms
• Grafana and Prometheus metrics (using the Yabeda framework)
• Docker container

How to run the application using Docker

Before starting, make sure you have Docker and Docker Compose installed.

Clone the repository

git clone https://github.com/rails-ministarter/rails-ministarter
cd rails-docker

Setup environment variables

Copy .env.example to .env in the root directory of the project

cp .env.example .env

And set the environment variables:

RAILS_DOCKER_POSTGRES_USERNAME=your_postgres_username
RAILS_DOCKER_POSTGRES_PASSWORD=your_postgres_password

These values will be used by Docker Compose for database configuration.

Build and run the application

Use Docker Compose to build and start the services defined in the docker-compose.yml file.

docker build -t rails-docker .
docker-compose build
docker-compose up

This will build the Docker image and start the application and database services.

Access the application

Once the containers are up and running, you can access the Rails application and Grafana in your browser.

• Rails application http://localhost:4000
• Grafana http://localhost:3000
• Prometheus http://localhost:9090

Grafana is provisioned with the default Prometheus data source via grafana/datasources/datasources.yaml. To test the connection,

• Log in to Grafana (admin/admin)
• Navigate to Home > Connections > Data Sources
• Select DS_PROMETHEUS, scroll down and click on the Test button. Grafana will try to connect to the Prometheus instance and fetch some data. If everything is set up correctly, you should see Successfully queried the Prometheus API..

How to run tests locally

Prepare the test database:

Run the following command to create and set up the test database:

rails db:test:prepare

Note: If you update your database schema (e.g., via migrations), you should run this command again to update the schema in the test database.

Now you can run the tests:

rails test

CI/CD

In order to enable the automatic upload of Docker images to Docker Hub through the CI/CD pipeline, you must configure the following environment variables in GitHub Actions:

• DOCKER_HUB_NAMESPACE
• DOCKER_HUB_REPOSITORY
• DOCKER_PASSWORD
• DOCKER_USERNAME