Action methods in Ruby on Rails - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is an action method in a Rails controller?

An action method is a public method inside a Rails controller that responds to a web request and renders a view or redirects the user.

beginner

How does Rails know which action method to call for a URL?

Rails uses routing rules defined in config/routes.rb to map URLs to specific controller action methods.

intermediate

What happens if an action method does not explicitly render or redirect?

Rails automatically renders a view template matching the action method name unless you specify otherwise.

intermediate

Can private methods in a Rails controller be used as action methods?

No, only public methods can be action methods. Private or protected methods cannot be called as actions from a web request.

advanced

Why should action methods be kept simple and focused?

Keeping action methods simple improves readability, maintainability, and helps separate concerns by moving complex logic to models or helpers.

Which of the following is true about Rails action methods?

A They are always private methods.

B They must return a string.

C They respond to web requests and render views or redirect.

D They are defined in the model.

Action methods are public controller methods that handle requests and render or redirect.

What file defines the URL to action method mapping in Rails?

A config/routes.rb

B app/controllers/application_controller.rb

C app/views/layouts/application.html.erb

D config/database.yml

Routes in config/routes.rb map URLs to controller action methods.

If an action method does not call render or redirect, what does Rails do?

A Raises an error.

B Renders a view matching the action name.

C Redirects to the home page.

D Does nothing.

Rails automatically renders the view template matching the action method name.

Which methods cannot be used as action methods in Rails?

A Private and protected methods

B Public methods

C Methods defined in helpers

D Methods in models

Only public methods in controllers can be action methods.

Why is it good practice to keep action methods simple?

A To make the code harder to read.

B To avoid using models.

C To increase the number of lines in the controller.

D To improve readability and maintainability.

Simple action methods make code easier to read and maintain.

Explain what an action method is in Rails and how it relates to routing and views.

Think about how a URL leads to a method that shows a page.

Describe why private methods cannot be action methods and how to organize controller code effectively.

Consider access control and code clarity.