    # File lib/chef/client.rb, line 275
        def register(client_name=node_name, config=Chef::Config)
          if File.exists?(config[:client_key])
            Chef::Log.debug("Client key #{config[:client_key]} is present - skipping registration")
          else
            Chef::Log.info("Client key #{config[:client_key]} is not present - registering")
            Chef::REST.new(config[:client_url], config[:validation_client_name], config[:validation_key]).register(client_name, config[:client_key])
          end
          # We now have the client key, and should use it from now on.
          self.rest = Chef::REST.new(config[:chef_server_url], client_name, config[:client_key])
        end