//Hariharnath Paduchuru Working Demo
#include <WiFi.h>
#include "secrets.h"
#include <WiFiClientSecure.h>
#include <PubSubClient.h>
#include <ArduinoJson.h>
#include "WiFi.h"
#include "DHTesp.h"
const int DHT_PIN = 15;
DHTesp dhtSensor;
#define AWS_IOT_PUBLISH_TOPIC "ESP32-Morgan/pub"
#define AWS_IOT_SUBSCRIBE_TOPIC "ESP32-Morgan/sub"
String umidade;
String temperatura;
WiFiClientSecure net = WiFiClientSecure();
PubSubClient client(net);
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.setServer(AWS_IOT_ENDPOINT, 8883);
// Create a message handler
client.setCallback(messageHandler);
Serial.println("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()
{
StaticJsonDocument<200> doc;
doc["humidity"] = umidade;
doc["temperature"] = temperatura;
char jsonBuffer[512];
serializeJson(doc, jsonBuffer); // print to client
client.publish(AWS_IOT_PUBLISH_TOPIC, jsonBuffer);
}
void messageHandler(char* topic, byte* payload, unsigned int length)
{
Serial.print("incoming: ");
Serial.println(topic);
StaticJsonDocument<200> doc;
deserializeJson(doc, payload);
const char* message = doc["message"];
Serial.println(message);
}
void setup() {
Serial.begin(115200);
Serial.print("Connecting to WiFi");
WiFi.begin("Wokwi-GUEST", "", 6);
while (WiFi.status() != WL_CONNECTED) {
delay(100);
Serial.print(".");
}
Serial.println(" Connected!");
dhtSensor.setup(DHT_PIN, DHTesp::DHT22);
connectAWS();
}
void loop() {
TempAndHumidity data = dhtSensor.getTempAndHumidity();
umidade = String(data.temperature, 2);
temperatura = String(data.humidity, 1);
Serial.println("Temp: " + String(data.temperature, 2) + "°C");
Serial.println("Umidade: " + String(data.humidity, 1) + "%");
Serial.println("---");
delay(2000); // Wait for a new reading from the sensor (DHT22 has ~0.5Hz sample rate)
publishMessage();
client.loop();
delay(5000);
}