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Installing Ruby on Rails with RVM on Ubuntu 20.04

Ruby on Rails is one of the most popular web app frameworks. It’s open-source software designed for developers to create successful projects while writing fewer codes. Having a fun and enjoyable development experience is one of the fundamental principles that make Ruby on Rails an attractive choice.

The RVM (Ruby Version Manager) tool, as the name suggests, is a third-party package manager that provides the development environment. RVM allows having multiple Ruby environments and switching between them seamlessly. The RVM project is free and open-source. The project is also available on GitHub.

This guide will demonstrate how to use RVM to establish a Ruby on Rails development environment on Ubuntu.

Prerequisites

This tutorial requires having access to a non-root sudo user on a properly configured Ubuntu server. We also have an in-depth guide on managing sudo access for Linux users. We will use RVM to manage our Ruby on Rails installation and management. For general users, RVM is recommended to use as a single-user only. However, it’s possible to install RVM for all users.

Installing RVM and Ruby on Rails

RVM supports almost all UNIX/Linux systems. The installation procedure should work on any Linux distro (including Ubuntu).

The primary dependencies for RVM installation are bash, curl, and gpg2 (and standard GNU tools). However, the installation script will auto-detect and install any dependencies (if needed).

First, install the GPG (GNU Privacy Guard). It will be necessary to verify the packages received from the RVM repo:

Gnu Package Install

RVM uses GPG keys to sign all their releases. We need the public GPG keys of RVM to verify the legitimacy of each RVM release we will download. Add the RVM public GPG keys:

gpg_recv_keys

The system is now ready to install RVM. Change the active directory to /tmp:

Next, download the RVM installation script:

curl_get_rvm

In addition, you can inspect the script before applying:

less /tmp/rvm.sh

less_rvm_sh

To install RVM, run the script. As we’re going to work with rails, add the --rails flag:

rvm_sh_stable_rails
  • Loading RVM

The installation is complete. We now need to load the RVM scripts into bash. The default installation location is /home/<username> directory:

source_rvm

Then, verify if RVM was loaded successfully:

rvm_type

Managing Ruby on Rails with RVM

RVM is now ready to use. We can also install specific versions of Ruby:

  • Listing available Ruby versions

The following RVM command will list all the available Ruby versions:

rvm_versions
  • Installing specific Ruby version

Use the following RVM command to install the target version of Ruby:

rvm_install
  • List installed Ruby versions

If there are multiple versions of Ruby installed, RVM can list them for you:

rvm_list
  • Switching to a different Ruby version

RVM allows switching to a different Ruby version. To change to a different Ruby version, use the following command:

rvm_use
  • Listing available Rails versions

The Rails framework is managed as a gem. This gives us the ability to manage various versions of Rails as well. The following gem command will list all the valid versions of Rails:

gem_search_rails
  • Installing different Rails versions

Once we have the target version of Rails, we can install it using the following gem command. Note that the Rails version will only refer to the version number:

gem_install_rails Ruby on Rails
  • Ruby on Rails gemsets

A gemset is a combo of Ruby and Rails together. It helps to manage Ruby on Rails easier. The gemsets will also have self-contained environments for gems. Moreover, they will have multiple environments for each Ruby version. Create a new gemset:

rvm_gemset_create

To specify a specific Ruby version to a gemset, use the following command:

gemset_create_with_version

JavaScript Runtime

Rails comes with some features that require a JavaScript runtime to function, for example, Asset Pipeline. We will install Node.js as the JavaScript runtime using the APT package manager.

Node.js has two versions – current (with latest features) and LTS (long-term support). For the most part, the LTS release is the go-to option. At the time of writing this article, the latest Node.js LTS release is version 14.17.3.

Similar to the RVM installation, Node.js offers an installation script to simplify the installation process. The following command will add the APT repository for the Node.js 14.x LTS release:

fetch_nodejs_repo Ruby on Rails

Once the Node.js repo is configured, update the APT package database:

apt_update2 Ruby on Rails

Finally, install Node.js:

install_nodejs

This is only the first step of Node.js installation. Check out the comprehensive guide on Node.js installation and configuration.

Uninstalling RVM

If RVM is no longer necessary, you can easily remove it from the system. First, remove the RVM source entry from the bashrc file:

rvm_source_entry_remove Ruby on Rails

Next, remove the following line from the file:

Save the file and close the editor. To take the changes into effect, reload bashrc:

source_bashrc

Finally, remove all the RVM-related files and directories:

remove_rvm

Final Thoughts

This guide covers the basics of how to implement RVM to install and manage Ruby on Rails. Using these methods, you can seamlessly use multiple Ruby environments. If you’re a beginner with RVM, then check out the official documentation for the RVM basics.

Happy Computing!