RESTful resource routes in Ruby on Rails - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ component_behavior

intermediate

What is the URL and HTTP method for the 'edit' action in a RESTful resource route?

Given a resource named articles, what is the correct URL path and HTTP method to access the edit action for the article with ID 5?

A POST /articles/5/edit

B GET /articles/5/edit

C GET /articles/edit/5

D PATCH /articles/5/edit

💡 Hint

Remember, the edit action shows a form to change an existing resource and uses GET.

The edit action in RESTful routes uses the GET method and the URL pattern /resource/:id/edit. For articles with ID 5, it is GET /articles/5/edit.

📝 Syntax

intermediate

Which route declaration creates all RESTful routes for a resource named 'products'?

In Rails routing, which line correctly generates all seven standard RESTful routes for the products resource?

A match 'products', via: :all

B resource :products

C get 'products'

D resources :products

💡 Hint

Plural form is important for multiple resources.

The resources :products declaration creates all seven RESTful routes (index, show, new, create, edit, update, destroy) for multiple products. resource (singular) is for a single resource without index.

❓ state_output

advanced

What controller action and params are triggered by this route?

Given the route resources :comments, what controller action and params hash will be called when a DELETE request is sent to /comments/42?

A Action: destroy, Params: { id: '42' }

B Action: delete, Params: { comment_id: '42' }

C Action: destroy, Params: { comment_id: '42' }

D Action: remove, Params: { id: '42' }

💡 Hint

The DELETE method on a resource with ID calls the destroy action with id param.

DELETE /comments/42 calls the destroy action in CommentsController with params[:id] = '42'. The param key is always id for RESTful routes.

🔧 Debug

advanced

Why does this custom route conflict with RESTful routes?

Consider these routes in routes.rb:

resources :users
get '/users/new', to: 'users#show'

What problem will this cause when accessing /users/new?

A The custom route overrides the RESTful 'new' action, causing the wrong controller action to run.

B The RESTful 'show' action will never be called for any user.

C It causes a syntax error in the routes file.

D No problem; both routes work fine together.

💡 Hint

Routes are matched top to bottom; custom routes can override RESTful ones.

The custom route get '/users/new' matches before the RESTful new route, so it calls users#show instead of users#new. This breaks the expected behavior for the 'new' page.

🧠 Conceptual

expert

How does Rails handle nested RESTful resource routes in URL and params?

Given these nested routes:

resources :authors do
  resources :books
end

What is the URL and params hash for accessing the 'show' action of book with ID 7 belonging to author with ID 3?

A URL: /authors/3/books/7, Params: { id: '3', book_id: '7' }

B URL: /books/7/authors/3, Params: { id: '7', author_id: '3' }

C URL: /authors/3/books/7, Params: { author_id: '3', id: '7' }

D URL: /books/7, Params: { author_id: '3', id: '7' }

💡 Hint

Nested resources include parent resource ID in URL and params with key named after parent resource.

Nested RESTful routes include the parent resource ID in the URL and params. For authors/3/books/7, params[:author_id] is '3' and params[:id] is '7'.