#include <WiFi.h>//library for wifi
#include < pubsubClient.h > //library for MQtt
#include "DHT.h"//Library for dht11
#define DHTPIN 4 //what pin we're connected to
#define DHTTYPE DHT11 //define type of sensor DHT 11
//#define LED 5
DHT dht (DHTPIN, DHTTYPE);//creating the instance by passing
const int potpin=34;
void callback(char* subscribetopic, byte* payload, unsigned int payloadLength);
//-------credentials of IBM Accounts------
#define ORG "P5awbw"//IBM ORGANITION ID
#define DEVICE_TYPE "Gasleak"//Device type mentioned in ibm watson IOT Platform
#define DEVICE_ID "1234" //Device ID mentioned in ibm watson IOT Platform
#define TOKEN "12345678" //Token
String data3;
float t;
int potvalue;
//-------- Customise the above values --------
char server[] = ORG ".messaging.internetofthings.ibmcloud.com";// Server Name
char publishTopic[] = "iot-2/evt/Data/fmt/json";// topic name and type of event perform and format in which data to be send
char subscribetopic[] = "iot-2/cmd/test/fmt/String";// cmd REPRESENT command type AND COMMAND IS TEST OF FORMAT STRING
char authMethod[] = "use-token-auth";// authentication method
char token[] = TOKEN;
char clientId[] = "d:" ORG ":" DEVICE_TYPE ":" DEVICE_ID;//client id
//-----------------------------------------
WiFiClient wifiClient; // creating the instance for wificlient
pubsubclient(server, 1883, callback ,wifiClient); //calling the predefined client id by passing parameter like server id,portand wificredential
void setup()// configureing the ESP32
{
Serial.begin(115200);
dht.begin();
//pinmode(LED,OUTPUT);
delay(10);
Serial.println();
wificonnect();
mqttconnect();
}
void loop()// Recursive Function
{
//h=dht.readhumidity();
t=dht.readtemperature();
potvalue=analogRead(potpin);
Serial.print("temperature: ");
Serial.println(t);
Serial.print("Leakage Threshold: ");
Serial.println(potvalue);
//serial.print("Humidity:");
//serial.println(h);
PublishTopic(t,potvalue);
delay(1000);
if (client.loop()) {
mqttconnect();
}
}
'/'.....................................retrieving to Cloud.............................../
void PublishData(float temp,float potenval) {
mqttconnect();//function call for connecting to ibm
/*
creating the String in in form JSon to update the data to ibm cloud
*/
String payload = "{\"temperature\":";
payload += temp;
String payload = "{\"LeakageThreshold\":";
payload += potenval;
payload += "}";
Serial.print("Sending payload: ");
Serial.println(payload);
if (client.publish(publishTopic, (char*) payload.c_str())) {
Serial.println("Publish ok");// if it sucessfully upload data on the cloud then it will print publish ok in Serial monitor or else it will print publish failed
} else {
Serial.println("Publish failed");
}
}
void mqttconnect() {
if (!client.connected()) {
Serial.print("Reconnecting client to ");
Serial.println(server);
while (!!!client.connect(clientId, authMethod, token)) {
Serial.print(".");
delay(500);
}
initManagedDevice();
Serial.println();
}
}
void wificonnect() //function defination for wificonnect
{
Serial.println();
Serial.print("Connecting to ");
WiFi.begin("Wokwi-GUEST", "", 6);//passing the wifi credentials to establish the connection
while (WiFi.status() != WL_CONNECTED) {
delay(500);
Serial.print(".");
}
Serial.println("");
Serial.println("WiFi connected");
Serial.println("IP address: ");
Serial.println(WiFi.localIP());
}
void initManagedDevice() {
if (client.subscribe(subscribetopic)) {
Serial.println((subscribetopic));
Serial.println("subscribe to cmd OK");
} else {
Serial.println("subscribe to cmd FAILED");
}
}
void callback(char* subscribetopic, byte* payload, unsigned int payloadLength)
{
Serial.print("callback invoked for topic: ");
Serial.println(subscribetopic);
for (int i = 0; i < payloadLength; i++) {
//Serial.print((char)payload[i]);
data3 += (char)payload[i];
}
Serial.println("data: "+ data3);
/*
if(data=="linhton")
{
serial.println(data3);
digitalwrite(LED,HIGH);
}
else
{
serial.println(data3);
digitalwrite(LEC,LOW);
}
*/
data3="";
}