discourse/app/controllers/finish_installation_controller.rb

class FinishInstallationController < ApplicationController
  skip_before_filter :check_xhr, :preload_json, :redirect_to_login_if_required
  layout 'finish_installation'

  before_filter :ensure_no_admins, except: ['confirm_email']

  def index
  end

  def register
    @allowed_emails = find_allowed_emails

    @user = User.new
    if request.post?
      email = params[:email].strip
      raise Discourse::InvalidParameters.new unless @allowed_emails.include?(email)

      return redirect_confirm(email) if User.where(email: email).exists?

      @user.email = email
      @user.username = params[:username]
      @user.password = params[:password]
      @user.password_required!

      if @user.save
        @email_token = @user.email_tokens.unconfirmed.active.first
        Jobs.enqueue(:critical_user_email, type: :signup, user_id: @user.id, email_token: @email_token.token)
        return redirect_confirm(@user.email)
      end

    end
  end

  def confirm_email
    @email = session[:registered_email]
  end

  protected

    def redirect_confirm(email)
      session[:registered_email] = email
      redirect_to(finish_installation_confirm_email_path)
    end

    def find_allowed_emails
      return [] unless GlobalSetting.respond_to?(:developer_emails) && GlobalSetting.developer_emails.present?
      GlobalSetting.developer_emails.split(",").map(&:strip)
    end

    def ensure_no_admins
      raise Discourse::InvalidAccess.new unless SiteSetting.has_login_hint?
    end
end