$ node-red

msg.payload = msg.payload.humidity;
return msg;

msg.payload = msg.payload.temperature;
return msg;

#include "secrets.h"
#include <WiFiClientSecure.h>
#include <MQTTClient.h>
#include <ArduinoJson.h>
#include <DHT.h>
#include <WiFi.h>

// AWS IoT 설정
#define AWS_IOT_PUBLISH_TOPIC   "esp32/pub"
#define AWS_IOT_SUBSCRIBE_TOPIC "esp32/sub"

// DHT11 센서 설정
#define DHT_PIN 13       // DHT11 데이터 핀
#define DHT_TYPE DHT11  // DHT11 센서

WiFiClientSecure net;
MQTTClient client;

DHT dht(DHT_PIN, DHT_TYPE);

void connectAWS()
{
  WiFi.mode(WIFI_STA);
  WiFi.begin(WIFI_SSID, WIFI_PASSWORD);

  Serial.println("Connecting to Wi-Fi");

  while (WiFi.status() != WL_CONNECTED){
    delay(500);
    Serial.print(".");
  }

  // Configure WiFiClientSecure to use the AWS IoT device credentials
  net.setCACert(AWS_CERT_CA);
  net.setCertificate(AWS_CERT_CRT);
  net.setPrivateKey(AWS_CERT_PRIVATE);

  // Connect to the MQTT broker on the AWS endpoint we defined earlier
  client.begin(AWS_IOT_ENDPOINT, 8883, net);

  // Create a message handler
  client.onMessage(messageHandler);

  Serial.print("Connecting to AWS IoT");

  while (!client.connect(THINGNAME)) {
    Serial.print(".");
    delay(100);
  }

  if(!client.connected()){
    Serial.println("AWS IoT Timeout!");
    return;
  }

  // Subscribe to a topic
  client.subscribe(AWS_IOT_SUBSCRIBE_TOPIC);

  Serial.println("AWS IoT Connected!");
}

void publishMessage(float temperature, float humidity)
{
  StaticJsonDocument<200> doc;
  doc["temperature"] = temperature;
  doc["humidity"] = humidity;
  char jsonBuffer[512];
  serializeJson(doc, jsonBuffer);

  client.publish(AWS_IOT_PUBLISH_TOPIC, jsonBuffer);
}

void messageHandler(String &topic, String &payload) {
  Serial.println("incoming: " + topic + " - " + payload);
}

void setup() {
  Serial.begin(9600);
  connectAWS();
  dht.begin();
}

void loop() {
  // 온습도 데이터 읽기
  float temperature = dht.readTemperature();
  float humidity = dht.readHumidity();
  Serial.println(temperature);
  Serial.println(humidity);

  // 온습도 데이터를 Node-RED로 전송
  // JSON 형식으로 데이터를 생성하여 MQTT 메시지로 전송
  StaticJsonDocument<200> doc;
  doc["temperature"] = temperature;
  doc["humidity"] = humidity;
  char jsonBuffer[512];
  serializeJson(doc, jsonBuffer);
  client.publish("node-red/esp32-data", jsonBuffer); // Node-RED에서 subscribe할 토픽을 "node-red/esp32-data"로 지정

  // AWS IoT에도 데이터를 전송
  publishMessage(temperature, humidity);

  // AWS IoT 클라이언트 루프
  client.loop();

  delay(1000);
}