ExchangeName = <<"custom.topic">>,
ExchangeType = <<"topic">>,
Key = <<"K">>,
Msg = <<"123">>,
{ok, Connection} = amqp_connection:start
    (#amqp_params_network{username = <<"guest">>, password = <<"guest">>, host = "192.168.1.1"}),
{ok, Channel} = amqp_connection:open_channel(Connection),
#'exchange.declare_ok'{} =
    amqp_channel:call(Channel, #'exchange.declare'{exchange=ExchangeName, durable=true, type = ExchangeType}),
amqp_channel:call(Channel, #'basic.publish'{routing_key = Key}, #amqp_msg{props = #'P_basic'{delivery_mode=2}, payload = Msg}),