def route_options destination_cidr_block, options = {}
client_opts = {}
client_opts[:route_table_id] = route_table_id
client_opts[:destination_cidr_block] = destination_cidr_block
if gateway = options[:internet_gateway]
gateway = gateway.id if gateway.is_a?(InternetGateway)
client_opts[:gateway_id] = gateway
end
if instance = options[:instance]
instance = instance.id if instance.is_a?(Instance)
client_opts[:instance_id] = instance
end
if interface = options[:network_interface]
interface = interface.id if interface.is_a?(NetworkInterface)
client_opts[:network_interface_id] = interface
end
client_opts
end