I use mqtt explorer . this I publish the topic nazneen/bin and subscribe the topic by esp32 . but problem is that I don't get any message to esp32 after subscribe the topic ..there is a code below
#ifdef ESP8266
#include <ESP8266WiFi.h> /* WiFi library for ESP8266 */
#else
#include <WiFi.h> /* WiFi library for ESP32 */
#endif
#include <Wire.h>
#include <PubSubClient.h>
#define wifi_ssid "yourSSID"
#define wifi_password "yourPASSWORD"
#define mqtt_server "test.mosquitto.org"
#define naz_topic "nazneen/bin"
WiFiClient espClient;
PubSubClient client(espClient);
void callback(char *topic, byte *payload, unsigned int length) {
Serial.print("Message arrived in topic: ");
Serial.println(topic);
Serial.print("Message:");
for (int i = 0; i < length; i++){
Serial.print((char)payload[i]);
}
Serial.println();
Serial.println("-----------------------");
}
void setup() {
Serial.begin(115200);
// dht.begin();
setup_wifi();
client.setServer(mqtt_server, 1883);
client.setCallback(callback);
}
void setup_wifi() {
delay(10);
// We start by connecting to a WiFi network
Serial.println();
Serial.print("Connecting to ");
Serial.println(wifi_ssid);
WiFi.begin(wifi_ssid, wifi_password);
while (WiFi.status() != WL_CONNECTED) {
delay(500);
Serial.print(".");
}
Serial.println("");
Serial.println("WiFi connected");
Serial.println("IP address: ");
Serial.println(WiFi.localIP());
}
void reconnect() {
// Loop until we're reconnected
while (!client.connected()) {
Serial.print("Attempting MQTT connection...");
if (client.connect("ESP8266Client")) {
Serial.println("connected");
} else {
Serial.print("failed, rc=");
Serial.print(client.state());
Serial.println(" try again in 5 seconds");
delay(5000);
}
}
}
void loop() {
if (!client.connected()) {
reconnect();
}
client.loop();
// client.publish(naz_topic, "welcome", true);
client.subscribe(naz_topic);
}
