Ruby on Rails Q & A


How to generate a new controller in Ruby on Rails?

In the Ruby on Rails framework, a controller is responsible for managing the flow of data between models and views. Creating a new controller is made simple with Rails’ built-in generators.


Here’s how you can generate a new Rails controller:


  1. Using the Generator: The most straightforward way to create a new controller is by using the Rails generator. In your terminal, navigate to the root directory of your Rails application and use the following command:



   rails generate controller ControllerName [actions]


   Replace `ControllerName` with the desired name for your controller (typically in CamelCase). The `[actions]` argument is optional and denotes methods you want to predefine in the controller. For example, if you wanted a `Books` controller with actions for `index` and `show`, you would run:



   rails generate controller Books index show



  1. What the Generator Produces: Running the above command will generate several files for you:


   – A controller file at `app/controllers/books_controller.rb` containing the predefined actions.

   – Views for each action inside `app/views/books/`.

   – Test files for the new controller in the `test` directory.

   – JavaScript, CoffeeScript, and stylesheets (SCSS) files for the controller in the `app/assets` directory.


  1. Editing the Controller: Open the generated controller file. You’ll find that Rails has created methods for each action you specified. Within these methods, you can define the logic for each action, such as fetching data from a model or rendering a particular view.


  1. Routing: The generator will also update the `config/routes.rb` file to include routes for the specified actions. You might need to adjust these routes or add more, depending on your application’s requirements.


Rails’ built-in generators make it straightforward to scaffold out new parts of your application. By understanding and utilizing these tools, you can rapidly develop features and maintain a structured and consistent codebase. Remember that while generators can speed up the development process, always ensure that you review and understand the generated code, tailoring it to your specific needs.

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Senior Software Engineer with a focus on remote work. Proficient in Ruby on Rails. Expertise spans y6ears in Ruby on Rails development, contributing to B2C financial solutions and data engineering.