MQTT, WebSocket oder MQTT über WSS? Wählen Sie nach Verantwortung

import mqtt from "mqtt";

const endpoint = "wss://public.runmqtt.com/mqtt";
const suffix = crypto.randomUUID().replaceAll("-", "");
const topic = `runmqtt/sandbox/${suffix}/loopback`;
const payload = JSON.stringify({
  source: "runmqtt-wss-guide",
  value: 42,
});

const client = mqtt.connect(endpoint, {
  clientId: `runmqtt-guide-${suffix}`,
  username: "<PUBLIC_SANDBOX_USERNAME>",
  password: "<PUBLIC_SANDBOX_PASSWORD>",
  clean: true,
  connectTimeout: 10_000,
  reconnectPeriod: 3_000,
  protocolVersion: 4,
});

client.on("connect", async () => {
  await client.subscribeAsync(topic, { qos: 1 });
  await client.publishAsync(topic, payload, { qos: 1 });
});

client.on("message", (_topic, _payload) => {
  console.info("Synthetic QoS 1 loopback received");
});

client.on("reconnect", () => console.info("Reconnecting"));
client.on("close", () => console.info("Disconnected"));
client.on("error", () => console.error("MQTT connection failed"));

export async function disconnect() {
  await client.endAsync();
}

window.addEventListener("pagehide", () => client.end(true));