Custom Params For Devise Auth

application_controller.rb

# app > controllers > application_controller.rb

# Before

class ApplicationController < ActionController::Base
end

# ------------------------------------------------------------------------------------------------------------

# After
class ApplicationController < ActionController::Base
  before_action :configure_permitted_parameters, if: :devise_controller?

  protected

  def configure_permitted_parameters
    devise_parameter_sanitizer.permit(:sign_up, keys: [:firstname, :lastname])
  end
end

new.html.erb

# app > devise > registrations

# Before

<h2>Sign up</h2>

<%= form_for(resource, as: resource_name, url: registration_path(resource_name)) do |f| %>
  <%= render "devise/shared/error_messages", resource: resource %>

  <div class="field">
    <%= f.label :firstname %><br />
    <%= text_field_tag :firstname, autofocus: true, autocomplete: "First Name" %>
  </div>

  <div class="field">
    <%= f.label :lastname %><br />
    <%= text_field_tag :lastname, autofocus: true, autocomplete: "Last Name" %>
  </div>

  <div class="field">
    <%= f.label :email %><br />
    <%= f.email_field :email, autofocus: true, autocomplete: "email" %>
  </div>

  <div class="field">
    <%= f.label :password %>
    <% if @minimum_password_length %>
    <em>(<%= @minimum_password_length %> characters minimum)</em>
    <% end %><br />
    <%= f.password_field :password, autocomplete: "new-password" %>
  </div>

  <div class="field">
    <%= f.label :password_confirmation %><br />
    <%= f.password_field :password_confirmation, autocomplete: "new-password" %>
  </div>

  <div class="actions">
    <%= f.submit "Sign up" %>
  </div>
<% end %>

<%= render "devise/shared/links" %>


# ----------

After

<h2>Sign up</h2>

<%= form_for(resource, as: resource_name, url: registration_path(resource_name)) do |f| %>
  <%= render "devise/shared/error_messages", resource: resource %>

  <div class="field">
    <%= f.label :firstname %><br />
    <%= f.text_field :firstname, autofocus: true, autocomplete: "First Name" %>
  </div>

  <div class="field">
    <%= f.label :lastname %><br />
    <%= f.text_field :lastname, autofocus: true, autocomplete: "Last Name" %>
  </div>

  <div class="field">
    <%= f.label :email %><br />
    <%= f.email_field :email, autofocus: true, autocomplete: "email" %>
  </div>

  <div class="field">
    <%= f.label :password %>
    <% if @minimum_password_length %>
    <em>(<%= @minimum_password_length %> characters minimum)</em>
    <% end %><br />
    <%= f.password_field :password, autocomplete: "new-password" %>
  </div>

  <div class="field">
    <%= f.label :password_confirmation %><br />
    <%= f.password_field :password_confirmation, autocomplete: "new-password" %>
  </div>

  <div class="actions">
    <%= f.submit "Sign up" %>
  </div>
<% end %>

<%= render "devise/shared/links" %>

rails_console.txt

# Before 

Form Input
[#<User id: 1, email: "michael@example.com", firstname: nil, lastname: nil, created_at: "2022-08-03 18:33:26.894118000 +0000", updated_at: "2022-08-03 18:33:26.894118000 +0000">, 

Form Input
#<User id: 2, email: "john.doe@example.com", firstname: nil, lastname: nil, created_at: "2022-08-03 19:07:04.798996000 +0000", updated_at: "2022-08-03 19:07:04.798996000 +0000">,

Manual Input
#<User id: 3, email: "jane.doe@example.com", firstname: "Jane", lastname: "Doe", created_at: "2022-08-03 19:10:31.575228000 +0000", updated_at: "2022-08-03 19:10:31.575228000 +0000">]

# -----------------------------------------------------------

# After Strong Typed

=> [#<User id: 1, email: "john.doe@example.com", firstname: "John ", lastname: "Doe", created_at: "2022-08-03 23:37:17.951277000 +0000", updated_at: "2022-08-03 23:37:17.951277000 +0000">]