til/rails/define-the-root-path-for-the-app.md

Define The Root Path For The App

The root_path helper that you might want to use in Rails controllers and views is not available by default.

> Rails.application.routes.url_helpers.root_path

ruby/3.2.2/lib/ruby/gems/3.2.0/gems/irb-1.14.0/lib/irb.rb:1285:in `full_message': undefined method `root_path' for #<Module:0x0000000106d11738> (NoMethodError)

Rails.application.routes.url_helpers.root_path
                                    ^^^^^^^^^^
Did you mean?  logout_path
               book_path

It needs to be declared in the config/routes.rb file with the controller action that it points to.

# config/routes.rb
Rails.application.routes.draw do
  root 'home#index'
end

Once this is defined the root_path will now be available with the rest of your URL helpers.

better-reads(dev)> reload!
Reloading...
better-reads(dev)> Rails.application.routes.url_helpers.root_path
=> "/"

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