    # File lib/fog/vcloud/compute.rb, line 13
          def check_href!(opts = {})
            self.href = connection.default_vdc_href unless href
            unless href
              if opts.is_a?(String)
                t = Hash.new
                t[:parent] = opts
                opts = t
              end
              msg = ":href missing, call with a :href pointing to #{if opts[:message]
                      opts[:message]
                    elsif opts[:parent]
                      "the #{opts[:parent]} whos #{self.class.to_s.split('::').last.downcase} you want to enumerate"
                    else
                      "the resource"
                    end}"
              raise Fog::Errors::Error.new(msg)
            end
          end