tap/app/controllers/sessions_controller.rb

class SessionsController < ApplicationController
  def new
  end

  def create
  	user = User.find_by(name: params[:session][:name])
    if user
    	log_in user
      redirect_back_or user
    else
    	#flash.now[:danger] = 'Invalid username'
    	render 'new'
    end
  end

  def destroy
    log_out
    redirect_to root_url
  end

end