Authentication HTTP Token with Rails 5.x

authenticate_token_rails.rb

#Add this line in controller
include ActionController::HttpAuthentication::Token::ControllerMethods
before_action :authenticate 

#Method to get the token via Header
#You can create some custom pattern, in this case I use Bearer.
  private

  def authenticate

    authenticate_or_request_with_http_token do |token|
      
      pattern = /^Bearer /
      header = request.headers['Authorization']
      header.gsub(pattern, '') if header && header.match(pattern)
      puts token

    end

  end