Named routes and path helpers in Ruby on Rails - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a named route in Rails?

A named route is a shortcut that Rails creates for a URL pattern. It lets you use a simple method name instead of writing the full URL or path every time.

beginner

How do you use a path helper in a Rails view?

You call the helper method like posts_path or new_post_path to get the URL or path string for that route. This helps keep your code clean and easy to change.

intermediate

Example: What does edit_user_path(@user) return?

It returns the URL path to edit the user with the ID of @user. For example, if @user.id is 5, it returns /users/5/edit.

beginner

Why are named routes and path helpers better than hardcoding URLs?

They make your code easier to read and maintain. If you change the route in one place, all helpers update automatically. It also helps avoid mistakes and broken links.

intermediate

How do you define a named route in Rails routes file?

You define it by giving a name to a route in config/routes.rb. For example, get 'profile', to: 'users#show', as: 'profile' creates a profile_path helper.

What does the helper new_post_path usually return?

A The URL path to show a post

B The URL path to create a new post form

C The full URL of the homepage

D The URL path to delete a post

new_post_path returns the path to the form where you can create a new post, usually /posts/new.

How do you pass a model instance to a path helper for a show page?

A You pass the model instance as an argument, e.g., <code>post_path(@post)</code>

B You pass the model's class name as a string

C You don't pass anything, just call <code>post_path</code>

D You pass the model's ID as a string only

Passing the model instance lets Rails extract the ID and build the correct path, like /posts/3.

What is the benefit of using named routes over hardcoded URLs?

A They only work in controllers

B They make the app slower

C They require more typing

D They automatically update if routes change

Named routes keep your code DRY and update automatically if you change routes.

Where do you define named routes in a Rails app?

A In the controller files

B In the view templates

C In <code>config/routes.rb</code>

D In the model files

All routes, including named routes, are defined in config/routes.rb.

What helper method would Rails create for this route? get 'dashboard', to: 'home#index', as: 'dashboard'

A <code>dashboard_path</code>

B <code>home_path</code>

C <code>index_path</code>

D <code>dashboard_url</code>

The as: 'dashboard' option creates the dashboard_path helper.

Explain what named routes and path helpers are in Rails and why they are useful.

Think about how you avoid repeating full URLs in your code.

Describe how you would use a path helper in a Rails view to link to a user's edit page.

Consider how you create links to edit forms in Rails.