Rails and Devise- How do I make the username migration unique and show an error if it is not?

Question

I am using devise for my rails app. I wanted to add the username field so I added a migration to the database. Now I want devise to validate the user_name field for uniqueness but I am not able to figure out how to do that. I also want it to show the error as it does with the default email field.

Answer 1

Just add validation for user_name in User model

validates :user_name, uniqueness: true

Answer 2

class ApplicationController < ActionController::Base
  # Prevent CSRF attacks by raising an exception.
  # For APIs, you may want to use :null_session instead.
  protect_from_forgery with: :exception
  before_action :configure_permitted_parameters, if: :devise_controller?



  protected  

  def configure_permitted_parameters
    devise_parameter_sanitizer.for(:sign_up) { |u| u.permit(:username, :email, :password, :password_confirmation, :remember_me) }
  end



end

User Model code change - add validation

class User < ActiveRecord::Base
  # Include default devise modules. Others available are:
  # :confirmable, :lockable, :timeoutable and :omniauthable
  devise :database_authenticatable, :registerable,
         :recoverable, :rememberable, :trackable, :validatable
  validates :username , uniqueness: {case_sesitive: false}

end