Route definition in routes.rb in Ruby on Rails - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to define a root route pointing to the home controller's index action.

Ruby on Rails

root to: '[1]'

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

A"main#index"

B"home#index"

C"home#index_action"

D"index#home"

Attempts:

3 left

💡 Hint

Common Mistakes

Swapping controller and action names.

Using incorrect action names like 'index_action'.

Using a controller name that doesn't exist.

The root route should point to the controller and action in the format "controller#action". Here, "home#index" means the index action of the home controller.

2fill in blank

medium

Complete the code to define RESTful routes for the articles resource.

Ruby on Rails

resources :[1]

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

Aarticles

Bcomments

Cposts

Dusers

Attempts:

3 left

💡 Hint

Common Mistakes

Using singular resource names with 'resources'.

Using unrelated resource names.

The 'resources' method defines RESTful routes for the given resource name. Here, we want routes for 'articles'.

3fill in blank

hard

Fix the error in the custom route definition to map GET /profile to users controller's show action.

Ruby on Rails

get '/profile', to: '[1]'

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

A"users#show"

B"profile#show"

C"users#profile"

D"show#users"

Attempts:

3 left

💡 Hint

Common Mistakes

Swapping controller and action names.

Using a non-existent controller or action.

The route should map to the 'show' action of the 'users' controller, so the correct format is "users#show".

4fill in blank

hard

Fill both blanks to define a named route 'login' that maps GET /login to sessions controller's new action.

Ruby on Rails

get '/login', to: '[1]', as: '[2]'

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

A"sessions#new"

B"users#new"

C"login"

D"signin"

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong controller or action in 'to:'.

Using incorrect or unrelated names in 'as:'.

The route maps to the 'new' action of the 'sessions' controller, and the route is named 'login' for easy reference.

5fill in blank

hard

Fill all three blanks to define a nested resource where comments belong to posts.

Ruby on Rails

resources :[1] do
  resources :[2], only: [:[3]]
end

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

Aposts

Bcomments

Ccreate

Dusers

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing up the order of nested resources.

Using incorrect action names in 'only:'.

This defines nested routes where 'comments' are nested inside 'posts', and only the 'create' action is available for comments.

Practice

1. What is the purpose of defining routes in the routes.rb file in a Rails application?

easy

A. To manage user sessions

B. To write database queries

C. To style the web pages

D. To connect URLs to specific controller actions

Solution

1. Step 1: Understand the role of routes in Rails

   Routes define how incoming web requests are matched to controller actions.

2. Step 2: Identify the correct purpose

   Connecting URLs to controller actions allows the app to respond correctly to user requests.

3. Final Answer:

   To connect URLs to specific controller actions -> Option D

4. Quick Check:

   Routes link URLs to actions [OK]

Hint: Routes map URLs to controller actions [OK]

Common Mistakes:

• Confusing routes with database queries
• Thinking routes handle styling
• Assuming routes manage sessions

2. Which of the following is the correct syntax to define a GET route for the URL /home that maps to the index action of the pages controller?

easy

A. route get '/home' => 'pages#index'

B. get 'pages#index', to: '/home'

C. get '/home', to: 'pages#index'

D. post '/home', to: 'pages#index'

Solution

1. Step 1: Recall the syntax for GET routes in Rails

   The correct syntax is get 'url', to: 'controller#action'.

2. Step 2: Match the URL and controller#action correctly

   get '/home', to: 'pages#index' correctly uses get '/home', to: 'pages#index'.

3. Final Answer:

   get '/home', to: 'pages#index' -> Option C

4. Quick Check:

   GET route syntax = get 'url', to: 'controller#action' [OK]

Hint: Use get 'url', to: 'controller#action' for GET routes [OK]

Common Mistakes:

• Swapping URL and controller#action positions
• Using post instead of get for GET routes
• Incorrect syntax like 'route get'

3. Given the following route definition in routes.rb:

resources :articles, only: [:index, :show]

What URLs will be available and which controller actions will they map to?

medium

A. /articles (GET) -> articles#index and /articles/:id (GET) -> articles#show

B. /articles/new (GET) -> articles#new and /articles/:id/edit (GET) -> articles#edit

C. /articles (POST) -> articles#create and /articles/:id (PATCH) -> articles#update

D. /articles/:id (DELETE) -> articles#destroy and /articles (GET) -> articles#index

Solution

1. Step 1: Understand the resources with only option

   It limits routes to only index and show actions.

2. Step 2: Identify URLs and actions for index and show

   index maps to GET /articles, show maps to GET /articles/:id.

3. Final Answer:

   /articles (GET) -> articles#index and /articles/:id (GET) -> articles#show -> Option A

4. Quick Check:

   resources with only index, show = GET /articles and GET /articles/:id [OK]

Hint: Only index and show create GET /collection and GET /collection/:id [OK]

Common Mistakes:

• Assuming all RESTful routes are created
• Confusing HTTP verbs for actions
• Mixing up new/edit with index/show

4. Identify the error in this route definition:

get '/profile', controller: 'users', action: 'show'

medium

A. URL should not start with a slash

B. Missing 'to:' keyword before controller#action

C. Should use 'post' instead of 'get'

D. Controller name should be capitalized

Solution

1. Step 1: Check correct syntax for get route with controller and action

   The correct syntax uses to: 'controller#action', not separate keys.

2. Step 2: Identify the missing 'to:' keyword

   The given code misses to: and incorrectly uses separate keys.

3. Final Answer:

   Missing 'to:' keyword before controller#action -> Option B

4. Quick Check:

   Use get '/url', to: 'controller#action' [OK]

Hint: Use 'to:' keyword for controller#action in routes [OK]

Common Mistakes:

• Omitting 'to:' keyword
• Using wrong HTTP verb
• Incorrect URL format

5. You want to create routes for a blog with posts and nested comments. Which route definition correctly creates RESTful routes for posts and nested comments inside routes.rb?

hard

A. resources :posts do
resources :comments
end

B. resources :posts, comments: true

C. resource :posts do
resource :comments
end

D. get '/posts/:post_id/comments', to: 'comments#index' only

Solution

1. Step 1: Understand nested resources syntax

   Nested resources are defined by placing one resources block inside another.

2. Step 2: Identify correct nested syntax for posts and comments

   resources :posts do resources :comments end correctly nests comments inside posts using a block.

3. Final Answer:

   resources :posts do resources :comments end -> Option A

4. Quick Check:

   Nested resources use block syntax [OK]

Hint: Nest resources inside block for nested routes [OK]

Common Mistakes:

• Using singular 'resource' instead of plural 'resources'
• Trying to pass nested resources as options
• Defining only one route manually