Suppose...
module Api
module V1
class SessionsController < ApplicationController
respond_to :json
skip_before_filter :verify_authenticity_token
def create
@user = User.find_by(email: params[:session][:email].downcase)
if @user && @user.authenticate(params[:session][:password])
token = User.new_remember_token
@user.update_attribute(:remember_token, User.digest(token))
respond_with :api, :v1, _____________
else
#error
end
end
end
end
end
The section marked as #error in the code above deals with situations where the user authentication fails. What specific coding method should be used to indicate to the caller that the authentication process was unsuccessful, or when there are issues such as unsaved data?