#include <WiFi.h>
#include <PubSubClient.h>
// MQTT Broker
const char *mqtt_broker = "broker.MQTTGO.io";
const char *topic = "emqx/esp32";
const char *mqtt_username = "";
const char *mqtt_password = "";
const int mqtt_port = 1883;
WiFiClient espClient;
PubSubClient client(espClient);
void setup() {
Serial.begin(9600);
Serial.print("Connecting to WiFi");
WiFi.begin("Wokwi-GUEST", "", 6);
while (WiFi.status() != WL_CONNECTED) {
delay(100);
Serial.print(".");
}
Serial.println(" Connected!");
client.setServer(mqtt_broker, mqtt_port);
while (!client.connected()) {
String client_id = "esp32-client-";
client_id += String(WiFi.macAddress());
Serial.printf("The client %s connects to the public MQTT broker\n", client_id.c_str());
if (client.connect(client_id.c_str(), mqtt_username, mqtt_password)) {
Serial.println("Public EMQX MQTT broker connected");
} else {
Serial.print("failed with state ");
Serial.print(client.state());
delay(2000);
}
}
}
void loop() {
// Publish and subscribe
client.publish(topic, "Hi, I'm ESP32 ^^!!!");
client.subscribe(topic);
delay(1000); // TODO: Build something amazing!
}