Gemfile and dependency management in Ruby on Rails - Mini Project: Build & Apply

Managing Dependencies with Gemfile in Rails

📖 Scenario: You are building a new Rails application that needs some external libraries (gems) to add features like authentication and styling.To keep your project organized and ensure everyone uses the same versions of these libraries, you will use a Gemfile to manage dependencies.

🎯 Goal: Create a Gemfile with specific gems and versions, then configure and install them properly to prepare your Rails app for development.

📋 What You'll Learn

Create a Gemfile with exact gem entries

Add a Ruby version declaration in the Gemfile

Use bundle install to install the gems

Add a group block for development and test gems

💡 Why This Matters

🌍 Real World

Managing dependencies with a Gemfile is essential for any Rails project to ensure all developers use the same library versions and avoid conflicts.

💼 Career

Understanding Gemfile and dependency management is a fundamental skill for Rails developers, crucial for maintaining stable and secure applications.

1

Create the initial Gemfile with Ruby version and main gems

Create a Gemfile that specifies Ruby version '3.2.2' and includes these gems exactly: rails version '7.0.4', pg version '1.4', and puma version '5.6'. Write the lines exactly as shown.

Ruby on Rails

# Your code here

Need a hint?

Start your Gemfile by declaring the Ruby version with ruby '3.2.2'. Then add each gem with gem 'name', 'version'.

2

Add a group block for development and test gems

Below the existing gems, add a group :development, :test do block that includes the gems byebug version '11.1' and rspec-rails version '5.0'. Close the group block properly.

Ruby on Rails

ruby '3.2.2'
gem 'rails', '7.0.4'
gem 'pg', '1.4'
gem 'puma', '5.6'
# Add development and test group gems below

Need a hint?

Use group :development, :test do to wrap gems used only in development and testing. Don't forget the end to close the block.

3

Run bundle install to install the gems

Run the command bundle install in your terminal to install all gems listed in the Gemfile and generate the Gemfile.lock file.

Ruby on Rails

ruby '3.2.2'
gem 'rails', '7.0.4'
gem 'pg', '1.4'
gem 'puma', '5.6'
group :development, :test do
  gem 'byebug', '11.1'
  gem 'rspec-rails', '5.0'
end
# Run bundle install in terminal

Need a hint?

Open your terminal in the project folder and type bundle install to install the gems and create Gemfile.lock.

4

Verify the Gemfile.lock and finalize setup

Confirm that the Gemfile.lock file is created and add a comment in your Gemfile that says # Gems installed and locked at the end of the file.

Ruby on Rails

ruby '3.2.2'
gem 'rails', '7.0.4'
gem 'pg', '1.4'
gem 'puma', '5.6'
group :development, :test do
  gem 'byebug', '11.1'
  gem 'rspec-rails', '5.0'
end
# Run 'bundle install' in terminal to install gems
# Add a comment confirming gems are installed

Need a hint?

Look for the Gemfile.lock file in your project folder after running bundle install. Then add the comment at the end of your Gemfile.