Ruby

Installing Ruby

Ruby Course

Introduction

Before we start learning, we’ll need to install Ruby first. This section is where you could potentially encounter a lot of errors.

Before continuing, let’s review a few best practices to keep in mind:

  • Copy and paste the commands to avoid typos.
  • Follow the directions closely, and don’t skip over any sections.
  • Do NOT use sudo unless The Odin Project specifically says to do so. Failing to follow this can cause a lot of headaches, and never run as the root user. In some instances, you might see a message in the terminal telling you to use sudo and install something with apt. Ignore that and follow our instructions for now.

Now, let’s get started!

Linux

Step 1: Install updates, packages and libraries

Before we can install Ruby, we need to install some base packages.

Step 1.1: Open the terminal

We’ll use the terminal to install all of the programs.

If you’re using Ubuntu or Xubuntu, press Ctrl + Alt + T to open the terminal. (This may work in other Linux distributions; you’ll have to try!)

Quick tip: In Linux, you can copy from the terminal with Ctrl + Shift + C and paste with Ctrl + Shift + V.

Step 1.2: Update Linux

The rest of the installation will take place inside the terminal window.

First, we need to make sure your Linux distribution is up to date. Run these commands one by one. Because these commands use sudo, you will have to enter your password in order for them to run. When typing your password, you may not get any visual feedback, but rest assured that your password is being entered. Once you’re done typing your password, press Enter.

sudo apt update
sudo apt upgrade

When it prompts you, press Y and then Enter.

Step 1.3: Install packages and libraries

Next, you need to install some required packages that do not come preinstalled. Be sure to copy and paste this command.

sudo apt install gcc make libssl-dev libreadline-dev zlib1g-dev libsqlite3-dev libyaml-dev

When it prompts you, press Y and then Enter. You may or may not have to type your password after pressing Enter.

Step 2: Install Ruby

Now you’re ready to install Ruby. We’re going to use a tool called rbenv, which makes it easy to install and manage Ruby versions.

Step 2.1: Install rbenv

First, you need to clone the rbenv repository.

git clone https://github.com/rbenv/rbenv.git ~/.rbenv

Next, we’ll add some commands to allow rbenv to work properly. We can use the Linux echo command to make it easy.

Run these commands one by one in sequence. They will not provide any output if done properly. Again, be sure to copy and paste these commands.

echo 'export PATH="$HOME/.rbenv/bin:$PATH"' >> ~/.bashrc
echo 'eval "$(rbenv init -)"' >> ~/.bashrc
exit

After running the final exit command, you will need to close out of all open terminals and open a new terminal (see Step 1.1 above).

Next, you need to install ruby-build to help compile the Ruby binaries. Run these commands in the terminal to create a directory for the ruby-build plugin and then download it to the proper directory.

mkdir -p "$(rbenv root)"/plugins
git clone https://github.com/rbenv/ruby-build.git "$(rbenv root)"/plugins/ruby-build

Finally, run

rbenv -v

from your terminal to verify that rbenv has been installed correctly. You should get an output with a version number similar to this:

rbenv 1.2.0-14-gc6cc0a1

If you do not get a version number at all (anything not starting with rbenv 1...), please ask for help in the Odin Project Chat Room.

Step 2.2: Install Ruby

It’s finally time to install Ruby using rbenv!

Inside the terminal, run this command:

rbenv install 3.3.0 --verbose

This command will take 10-15 minutes to complete. The --verbose flag will show you what’s going on so you can be sure it hasn’t gotten stuck. While it installs, take this time to watch funny jumping goats video or to get a glass of water.

You may get this error message:

ruby-build: definition not found: x.x.x

See all available versions with `rbenv install --list'.

If the version you need is missing, try upgrading ruby-build:

  git -C /home/itorja/.rbenv/plugins/ruby-build pull

If so, we run the suggested command:

git -C "$(rbenv root)"/plugins/ruby-build pull

Once Ruby is installed, you need to tell rbenv which version to use by default. Inside the terminal, type:

rbenv global 3.3.0

Then,

ruby -v

The above command should return something similar to this:

ruby 3.3.0pxx (20xx-xx-xx revision xxxxx) [x86_64-linux]

where x represents the version available at the time you installed Ruby.

Well done! Pat yourself on the back! The hard part is done, and it’s time to move on to the next lesson!

MacOS

Step 1: Install packages and libraries

Before we can install Ruby, we need to install some base packages. We will use the terminal to install all of the programs.

Step 1.1: Open the terminal

In your Applications folder, find “Utilities” and double click “Terminal”. Alternatively, using Spotlight (Cmd + Space) or Launchpad, type “Terminal”.

The rest of the instructions are done inside this terminal window.

Step 1.2: Install Xcode

First, you need to install Xcode, which is a program provided by Apple for programming. Xcode will install many programs that are needed for Ruby and Git and should take 10-15 minutes to install.

Type xcode-select --install in your terminal and press Enter. You may need to click “Install” when prompted.

Step 1.3: Install Homebrew

The next program you need to install is Homebrew, which makes it easy to install other programs you’ll need. From inside the terminal, type the following:

/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"

You will be prompted to enter your password. When typing your password, you may not get any visual feedback, but rest assured that your password is being entered. Once you’re done typing your password, press Enter.

Congratulations! You’ve installed the prerequisites!

Step 2: Install Ruby

Now you’re ready to install Ruby. We’re going to use a tool called rbenv, which makes it easy to manage Ruby versions.

Step 2.1: Install ruby-build

First, let’s install ruby-build:

brew install ruby-build

ruby-build will make it possible to install our Ruby version of choice.

Step 2.2: Install rbenv

To install rbenv, run the following in your terminal:

brew install rbenv

Then, run this command:

rbenv init

You should see one of two messages after the command has run.

Either:

# Load rbenv automatically by appending
# the following to ~/.bash_profile:

eval "$(rbenv init -)"

Or:

# Load rbenv automatically by appending
# the following to ~/.zshrc:

eval "$(rbenv init -)"

You’ll do as it suggests by running either of the following commands in the terminal.

If the previous message stated you should append to your bash_profile then run:

echo 'eval "$(rbenv init -)"' >> ~/.bash_profile

Otherwise if it mentioned zshrc then run:

echo 'eval "$(rbenv init -)"' >> ~/.zshrc

You’ll notice nothing happened in the terminal. That’s okay and is typical response for many terminal commands. At this point, take note of the page and step number you are on, close everything, do a full reboot and log back into your profile. After logging back in, re-open the terminal (see Step 1.1).

Step 2.3: Install Ruby

We can now (finally) install Ruby! Our curriculum currently uses version 3.3.0, which will allow you to complete this path’s materials and content without error. We upgrade the material to accommodate newer versions as necessary. Without further ado, let’s get going!

First, let’s upgrade ruby-build:

brew upgrade ruby-build

Now we’re ready to install our desired version of Ruby:

rbenv install 3.3.0 --verbose

This command will take 10-15 minutes to complete. The --verbose flag will show you what’s going on so you can be sure it hasn’t gotten stuck. While it installs, take this time to watch funny jumping goats video or to get a glass of water.

Once Ruby is installed, you need to tell rbenv which version to use by default. Inside the terminal, type:

rbenv global 3.3.0

You can double check that this worked by typing ruby -v and checking that the output says version 3.3.0:

ruby -v
ruby 3.3.0pxx (20xx-xx-xx revision xxxxx) [x86_64-darwin18]

If you don’t see the output above, close and reopen the terminal window and then run the command again.

Well done! Pat yourself on the back! The hard part is done, and it’s time to move on to the next lesson!

Extras

If you are using Visual Studio Code as your IDE, you can install the “Ruby LSP” extension, which will provide you with semantic highlighting and formatting support.

Using the extension is optional, but it is a quick install; go to the “Extensions” tab in VSC (Ctrl + Shift + X), search “Ruby LSP”, and click install on the first one. Congratulations, the extension is now installed.

The most important features Ruby LSP provides will work out of the box. But it may bug you about using a monorepo setup, missing lockfiles or rubocop - you can choose “Don’t show again” for now. We will introduce these later.

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