Rails installation and setup - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to install Rails using the gem command.

Ruby on Rails

gem install [1]

Drag options to blanks, or click blank then click option'

Abundler

Bruby

Crails

Drake

Attempts:

3 left

💡 Hint

Common Mistakes

Typing 'ruby' instead of 'rails' in the install command.

Trying to install 'bundler' instead of 'rails'.

The command gem install rails installs the Rails framework on your system.

2fill in blank

medium

Complete the command to create a new Rails application named 'blog'.

Ruby on Rails

rails [1] blog

Drag options to blanks, or click blank then click option'

Astart

Binit

Ccreate

Dnew

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'start' or 'create' instead of 'new'.

Using 'init' which is not a Rails command.

The command rails new blog creates a new Rails application named 'blog'.

3fill in blank

hard

Fix the error in the command to start the Rails server.

Ruby on Rails

rails [1]

Drag options to blanks, or click blank then click option'

As

Bstart

Crun

Dserve

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'run' or 'start' which are not valid Rails server commands.

Using 'serve' which is not recognized.

The shorthand command rails s starts the Rails server quickly.

4fill in blank

hard

Fill both blanks to install dependencies and start the Rails console.

Ruby on Rails

bundle [1] && rails [2]

Drag options to blanks, or click blank then click option'

Ainstall

Bconsole

Cserver

Dupdate

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'update' instead of 'install' for bundle.

Using 'server' instead of 'console' for Rails command.

bundle install installs all gem dependencies.
rails console opens the Rails console for interactive commands.

5fill in blank

hard

Fill both blanks to generate a scaffold for a Post model with title and body fields.

Ruby on Rails

rails generate [1] Post title:string [2]:text

Drag options to blanks, or click blank then click option'

Ascaffold

Bbody

Cmigration

Dmodel

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'model' instead of 'scaffold' which generates less files.

Forgetting to specify 'body' as a field name.

The command rails generate scaffold Post title:string body:text creates all files for a model, views, controller, and migration.

Practice

1. What is the main purpose of running gem install rails in your terminal?

easy

A. To install the Rails framework on your computer

B. To create a new Rails project

C. To start the Rails server

D. To update Ruby to the latest version

Solution

1. Step 1: Understand the command gem install rails

   This command uses Ruby's package manager (gem) to install the Rails framework on your system.

2. Step 2: Differentiate from other commands

   Creating a project uses rails new, and starting the server uses rails server. Updating Ruby is separate.

3. Final Answer:

   To install the Rails framework on your computer -> Option A

4. Quick Check:

   Install Rails = gem install rails [OK]

Hint: Install Rails with gem install rails command [OK]

Common Mistakes:

• Confusing installation with project creation
• Trying to start server before installing Rails
• Mixing Ruby update with Rails installation

2. Which command correctly creates a new Rails application named myapp?

easy

A. rails create myapp

B. rails new myapp

C. gem new myapp

D. rails start myapp

Solution

1. Step 1: Identify the correct Rails command for project creation

   The command to create a new Rails app is rails new appname.

2. Step 2: Check each option

   rails create myapp uses 'create' which is incorrect. gem new myapp uses 'gem' which manages packages, not projects. rails start myapp uses 'start' which is for running the server.

3. Final Answer:

   rails new myapp -> Option B

4. Quick Check:

   Create app = rails new [OK]

Hint: Use rails new appname to create a project [OK]

Common Mistakes:

• Using 'rails create' instead of 'rails new'
• Confusing gem commands with Rails commands
• Trying to start app with wrong command

3. After running rails new blog and then cd blog, what happens when you run rails server?

medium

A. Starts a web server accessible at http://localhost:3000

B. Creates a new Rails project named blog

C. Installs Rails gems needed for the project

D. Displays an error because the server command is invalid

Solution

1. Step 1: Understand the rails server command

   This command starts the Rails web server so you can view your app in a browser.

2. Step 2: Confirm the server address

   By default, the server runs on port 3000 and is accessible at http://localhost:3000.

3. Final Answer:

   Starts a web server accessible at http://localhost:3000 -> Option A

4. Quick Check:

   rails server = start web server [OK]

Hint: rails server runs app at localhost:3000 [OK]

Common Mistakes:

• Thinking rails server creates a project
• Expecting gem installation during server start
• Assuming server command is invalid

4. You ran rails new myapp but got an error saying 'command not found: rails'. What is the most likely cause?

medium

A. Ruby is not installed on your system

B. You forgot to create the project folder manually

C. Rails gem is not installed or not in your PATH

D. You need to run rails server first

Solution

1. Step 1: Analyze the error 'command not found: rails'

   This error means the system cannot find the rails command, usually because the Rails gem is missing or not accessible.

2. Step 2: Check other options

   Creating a folder manually is not needed; Ruby missing would cause a different error; running server first is unrelated.

3. Final Answer:

   Rails gem is not installed or not in your PATH -> Option C

4. Quick Check:

   Missing rails gem = command not found [OK]

Hint: Install Rails gem before using rails commands [OK]

Common Mistakes:

• Assuming folder must be created manually
• Confusing Ruby absence with Rails command error
• Trying to run server before project exists

5. You want to create a new Rails app but skip installing all default gems to speed up setup. Which command should you use?

hard

A. rails new appname --skip-install

B. rails new appname --no-gems

C. gem install rails --skip-defaults

D. rails new appname --skip-bundle

Solution

1. Step 1: Identify the option to skip gem installation during project creation

   The --skip-bundle flag tells Rails to create the app without running bundle install which installs gems.

2. Step 2: Evaluate other options

   rails new appname --no-gems is invalid syntax, gem install rails --skip-defaults misuses gem install, rails new appname --skip-install is not a recognized flag.

3. Final Answer:

   rails new appname --skip-bundle -> Option D

4. Quick Check:

   Skip gem install = --skip-bundle [OK]

Hint: Use --skip-bundle to skip gem install on new app [OK]

Common Mistakes:

• Using invalid flags like --no-gems or --skip-install
• Trying to skip gem install with gem install command
• Confusing bundle install with rails new options