Creating a Ruby on Rails app with RVM on Ubuntu

I wrote this step-by-step to help me remember it next time I create an app.

It’s my first time experimenting with Rails. I wanted to use a virtual environment from the start because that’s how I learned Python-Django too, and to not be afraid of setting things up.

This guide might grow as I learn more details of the process. For example, at this point I’m not sure how updates to the system Ruby version would affect the project.

I’m using Ubuntu 16.10.

Install Ruby

Install rvm

Create virtual environment

$ rvm gemset create <name>

Activate virtual environment

$ rvm @<name>

Check which one is being used

$ rvm gemset list

gemsets for ruby-2.4.0 (found in /home/felipe/.rvm/gems/ruby-2.4.0)
   (default)
   global
=> learn_rails

Install rails

$ gem install rails

Check rails

$ rails --version

Rails 5.1.X

Create new app

$ rails new blog
$ cd blog

Run server

$ bin/rails server

I got an error:

@learn_rails/gems/bundler-1.15.3/lib/bundler/runtime.rb:85:in `rescue in block (2 levels) in require': There was an error while trying to load the gem 'uglifier'. (Bundler::GemRequireError)

A JS runtime was missing. So I went to blog/Gemfile and uncommented line 20:

gem 'therubyracer', platforms: :ruby/

Then installed the new gem.

$ bundle install
Bundle complete! 17 Gemfile dependencies, 73 gems now installed.
Use `bundle info [gemname]` to see where a bundled gem is installed.

Now the server ran fine:

$ bin/rails server

Browse to: http://localhost:3000

All set!

Written by Felipe Freitag who lives and works in Porto Alegre, coding and drawing. Follow on twitter