Why routing maps URLs to actions in Ruby on Rails - Challenge Your Understanding

Challenge - 5 Problems

🧠 Conceptual

intermediate

What does routing do in Rails?

In Rails, what is the main purpose of routing?

A It connects URLs to specific controller actions that handle requests.

B It stores user data in the database automatically.

C It styles the HTML pages with CSS.

D It compiles Ruby code into machine code.

💡 Hint

Think about how a web address leads to a page or action.

Routing in Rails links a URL to a controller action, which decides what to do next.

❓ component_behavior

intermediate

What happens when you visit '/posts/5'?

Given this route in Rails: get '/posts/:id', to: 'posts#show', what action is triggered when visiting '/posts/5'?

Ruby on Rails

get '/posts/:id', to: 'posts#show'

A The application returns a 404 error because the route is invalid.

B The 'show' action in the PostsController is called with id = 5.

C The 'edit' action in the PostsController is called with id = 5.

D The 'index' action in the PostsController is called.

💡 Hint

Look at the route pattern and the controller#action format.

The route matches '/posts/:id' and sends the request to the 'show' action with the id parameter.

📝 Syntax

advanced

Identify the correct route syntax for a 'create' action

Which of the following route definitions correctly maps a POST request to the 'create' action in the 'articles' controller?

A post '/articles', to: 'articles#create'

B get '/articles/create', to: 'articles#create'

C put '/articles', to: 'articles#create'

D delete '/articles', to: 'articles#create'

💡 Hint

Remember which HTTP verb is used to create new resources.

POST requests are used to create new resources, so the route must use 'post'.

🔧 Debug

advanced

Why does this route cause an error?

Given the route: get '/users/:id/edit', to: 'users#edit', why does visiting '/users/edit' cause an error?

Ruby on Rails

get '/users/:id/edit', to: 'users#edit'

A Because the 'edit' action does not exist in UsersController.

B Because the HTTP verb should be POST, not GET.

C Because '/users/edit' does not match the pattern requiring an :id before '/edit'.

D Because the route should be defined with 'resources :users' instead.

💡 Hint

Look carefully at the URL pattern and what parts are required.

The route expects an :id between '/users/' and '/edit', so '/users/edit' misses the id.

❓ state_output

expert

What is the output of this routing helper?

Given the route resources :products, what is the output of product_path(10) in a Rails view?

Ruby on Rails

resources :products

A "/products/10/edit"

B "/products/show/10"

C "/products?id=10"

D "/products/10"

💡 Hint

Think about the URL pattern for showing a single resource.

The helper product_path(10) generates the URL to show the product with id 10, which is '/products/10'.