Docked Rails

Setting up Rails for the first time with all the dependencies necessary can be daunting for beginners. Docked Rails uses a Rails CLI Docker image to make it much easier. You can start a new Rails application, working with that application during development, and run a basic server without installing anything besides Docker on your machine.

Getting started

First install Docker (and WSL on Windows). Then copy'n'paste to run in the terminal:

docker volume create ruby-bundle-cache
alias rails='docker run --rm -it -v $PWD:/rails -v ruby-bundle-cache:/bundle ghcr.io/rails/cli'
alias rails-server='docker run --rm -it -v $PWD:/rails -v ruby-bundle-cache:/bundle -p 3000:3000 ghcr.io/rails/cli server -b 0.0.0.0'

Then you're ready to create your first Rails app:

rails new weblog
cd weblog
rails generate scaffold post title:string body:text
rails db:migrate
rails-server

That's it! You're running Rails with your weblog on http://localhost:3000/posts.

Working with JavaScript-bundled Rails apps

The default for Rails 7 is to rely on importmaps for JavaScript, so you don't need to use any JavaScript build process. But if you know you need to work with React, or other heavy JavaScript front-end tooling, you should use Rails together with JS bundling. To setup, follow the same steps as above, then add the following alias:

alias rails-dev='docker run --rm -it -v $PWD:/rails -v ruby-bundle-cache:/bundle -p 3000:3000 --entrypoint bin/dev ghcr.io/rails/cli'

Then create your app:

rails new weblog -j esbuild
cd weblog
rails generate scaffold post title:string body:text
rails db:migrate
# Edit the Procfile.dev in the root and change the first line to: `web: bin/rails server -p 3000 -b 0.0.0.0`
rails-dev

Now your development server will automatically compile any changes you make to the JavaScript in the project. Like with first setup, your weblog is running on http://localhost:3000/posts.

Mapping additional commands

In addition to the alias for rails and rails-server (or rails-dev), it can be helpful also to map bundle, rake, or even yarn to run via Docker:

alias bundle='docker run --rm -it -v $PWD:/rails -v ruby-bundle-cache:/bundle --entrypoint bundle ghcr.io/rails/cli'
alias rake='docker run --rm -it -v $PWD:/rails -v ruby-bundle-cache:/bundle --entrypoint rake ghcr.io/rails/cli'
alias rails-yarn='docker run --rm -it -v $PWD:/rails -v ruby-bundle-cache:/bundle --entrypoint yarn ghcr.io/rails/cli'

Work to be done

1. Change the Procfile.dev in rails to bind to 0.0.0.0 by default?