This example illustrates the process of setting up the Client to connect to the Broker via Websocket/TCP and publish a "Hello World!" message.

#include <iostream>
#include <string>

#include <boost/asio/io_context.hpp>
#include <boost/asio/detached.hpp>
#include <boost/asio/ip/tcp.hpp>

#include <boost/beast/websocket.hpp>

#include <async_mqtt5/logger.hpp>
#include <async_mqtt5/mqtt_client.hpp>
#include <async_mqtt5/types.hpp>

#include <async_mqtt5/websocket.hpp> // WebSocket traits

struct config {
	std::string brokers = "broker.hivemq.com/mqtt"; // Path example: localhost/mqtt
	uint16_t port = 8000; // 8083 is the default Webscoket/TCP MQTT port. However, HiveMQ's public broker uses 8000 instead.
	std::string client_id = "async_mqtt5_tester";
};

int main(int argc, char** argv) {
	config cfg;

	if (argc == 4) {
		cfg.brokers = argv[1];
		cfg.port = uint16_t(std::stoi(argv[2]));
		cfg.client_id = argv[3];
	}

	boost::asio::io_context ioc;

	// Construct the Client with WebSocket/TCP as the underlying stream and enabled logging.
	// Since we are not establishing a secure connection, set the TlsContext template parameter to std::monostate.
	async_mqtt5::mqtt_client<
		boost::beast::websocket::stream<boost::asio::ip::tcp::socket>,
		std::monostate,
		async_mqtt5::logger
	> client(ioc, {}, async_mqtt5::logger(async_mqtt5::log_level::info));

	// If you want to use the Client without logging, initialise it with the following line instead.
	//async_mqtt5::mqtt_client<boost::beast::websocket::stream<boost::asio::ip::tcp::socket>> client(ioc);

	client.brokers(cfg.brokers, cfg.port) // Broker that we want to connect to.
		.credentials(cfg.client_id) // Set the Client Identifier. (optional)
		.async_run(boost::asio::detached); // Start the Client.

	client.async_publish<async_mqtt5::qos_e::at_most_once>(
		"async-mqtt5/test", "Hello world!",
		async_mqtt5::retain_e::no, async_mqtt5::publish_props {},
		[&client](async_mqtt5::error_code ec) {
			std::cout << ec.message() << std::endl;
			client.async_disconnect(boost::asio::detached);
		}
	);

	ioc.run();
}