# File lib/fog/aws/requests/compute/modify_network_interface_attribute.rb, line 47
        def modify_network_interface_attribute(network_interface_id, attribute, value)
          response = Excon::Response.new
          if self.data[:network_interfaces][network_interface_id]
            nic = self.data[:network_interfaces][network_interface_id]
            
            case attribute
            when 'description'
              nic['description'] = value.clone
            when 'groupSet'
              groups = {}
              value.each do |group_id|
                name = self.data[:security_groups].select { |k,v| v['groupId'] == group_id } .first.first
                if name.nil?
                  raise Fog::Compute::AWS::Error.new("Unknown security group '#{group_id}' specified")
                end
                groups[group_id] = name
              end
              nic['groupSet'] = groups
            when 'sourceDestCheck'
              nic['sourceDestCheck'] = value
            when 'attachment'
              if nic['attachment'].nil? || value['attachmentId'] != nic['attachment']['attachmentId']
                raise Fog::Compute::AWS::Error.new("Illegal attachment '#{value['attachmentId']}' specified")
              end
              nic['attachment']['deleteOnTermination'] = value['deleteOnTermination']
            else
              raise Fog::Compute::AWS::Error.new("Illegal attribute '#{attribute}' specified")
            end

            response.status = 200
            response.body = {
              'requestId' => Fog::AWS::Mock.request_id,
              'return'    => true
            }

            response
          else
            raise Fog::Compute::AWS::NotFound.new("The network interface '#{network_interface_id}' does not exist")
          end
        end