#include <WiFi.h>
#include <PubSubClient.h>
#include <DHTesp.h>
const int DHT_PIN = 15;
DHTesp dht;
// Update these with values suitable for your network.
const char* ssid = "Wokwi-GUEST";
const char* password = "";
const char* mqtt_server = "test.mosquitto.org";
WiFiClient espClient;
PubSubClient client(espClient);
unsigned long lastMsg = 0;
float temp = 0;
float hum = 0;
void setup_wifi() { //perintah koneksi wifi
delay(10);
// We start by connecting to a WiFi network
Serial.println();
Serial.print("Connecting to ");
Serial.println(ssid);
WiFi.mode(WIFI_STA); //setting wifi chip sebagai station/client
WiFi.begin(ssid, password); //koneksi ke jaringan wifi
while (WiFi.status() != WL_CONNECTED) { //perintah tunggu esp32 sampi terkoneksi ke wifi
delay(500);
Serial.print(".");
}
randomSeed(micros());
Serial.println("");
Serial.println("WiFi connected");
Serial.println("IP address: ");
Serial.println(WiFi.localIP());
}
void callback(char* topic, byte* payload, unsigned int length) { //perintah untuk menampilkan data ketika esp32 di setting sebagai subscriber
Serial.print("Message arrived [");
Serial.print(topic);
Serial.print("] ");
for (int i = 0; i < length; i++) { //mengecek jumlah data yang ada di topik mqtt
Serial.print((char)payload[i]);
}
Serial.println();
// Switch on the LED if an 1 was received as first character
if ((char)payload[0] == '1') {
digitalWrite(2, LOW); // Turn the LED on (Note that LOW is the voltage level
// but actually the LED is on; this is because
// it is active low on the ESP-01)
} else {
digitalWrite(2, HIGH); // Turn the LED off by making the voltage HIGH
}
}
void reconnect() { //perintah koneksi esp32 ke mqtt broker baik itu sebagai publusher atau subscriber
// Loop until we're reconnected
while (!client.connected()) {
Serial.print("Attempting MQTT connection...");
// perintah membuat client id agar mqtt broker mengenali board yang kita gunakan
String clientId = "ESP32Client-";
clientId += String(random(0xffff), HEX);
// Attempt to connect
if (client.connect(clientId.c_str())) {
Serial.println("Connected");
// Once connected, publish an announcement...
client.publish("/indobot/p/mqtt", "Indobot"); //perintah publish data ke alamat topik yang di setting
// ... and resubscribe
client.subscribe("/indobot/p/mqtt"); //perintah subscribe data ke mqtt broker
} else {
Serial.print("failed, rc=");
Serial.print(client.state());
Serial.println(" try again in 5 seconds");
// Wait 5 seconds before retrying
delay(5000);
}
}
}
void setup() {
pinMode(2, OUTPUT); // inisialisasi pin 2 / ledbuiltin sebagai output
Serial.begin(115200);
setup_wifi(); //memanggil void setup_wifi untuk dieksekusi
client.setServer(mqtt_server, 1883); //perintah connecting / koneksi awal ke broker
client.setCallback(callback); //perintah menghubungkan ke mqtt broker untuk subscribe data
dht.setup(DHT_PIN, DHTesp::DHT22);//inisialiasi komunikasi dengan sensor dht22
}
void loop() {
if (!client.connected()) {
reconnect();
}
client.loop();
unsigned long now = millis();
if (now - lastMsg > 2000) { //perintah publish data
lastMsg = now;
TempAndHumidity data = dht.getTempAndHumidity();
String temp = String(data.temperature, 2); //membuat variabel temp untuk di publish ke broker mqtt
client.publish("/indobot/p/temp", temp.c_str()); //publish data dari varibel temp ke broker mqtt
String hum = String(data.humidity, 1); //membuat variabel hum untuk di publish ke broker mqtt
client.publish("/indobot/p/hum", hum.c_str()); //publish data dari varibel hum ke broker mqtt
Serial.print("Temperature: ");
Serial.println(temp);
Serial.print("Humidity: ");
Serial.println(hum);
}
}