This section explains how you can work with controllers in a Rails 5 application, including: how to work with sessions in Rails, understanding params, and reviewing data flow.

This guide walks through how to work with the params hash in a Rails 5 application, including how to access params from the controller and view.

This guide explains how you can work with sessions in Rails 5 to share data between pages, and how to pull data from the params hash.

This guide walks through how to refactor the session tracking system into its own controller concern to improve the code organization in the Rails 5 application.

Strong parameters can help to protect your site from malicious hacking attempts. In this guide we'll walk through what strong params are, how to make them optional, and how to build a strong param method from scratch.

The null object pattern is a helpful design pattern that enables methods to be called with more confidence. In this deep dive we'll walk through how to implement the null object pattern in a Rails application to override the Devise current_user method to enable a guest user feature.