#include <SoftwareSerial.h>
SoftwareSerial mySerial(12, 13); // RX, TX

#include <ESP8266WiFi.h>          //https://github.com/esp8266/Arduino
#include <DNSServer.h>
#include <ESP8266WebServer.h>
#include "WiFiManager.h"          //https://github.com/tzapu/WiFiManager

int count=0,i,m,j,k;
int t,t1,t2,t3;
int outputpin= A0;//ds18b20 

//////////////////////////////////////// ALL DECLARATIONS for CLOUD //////////////////////////////
const char* host = "api.thingsio.ai";                                 // OR host = devapi2.thethingscloud.com
const char* post_url = "/devices/deviceData";       // OR /api/v2/thingscloud2/_table/data_ac
const char* time_server = "baas.thethingscloud.com";             //this is to convert timestamp
const int httpPort = 80;

char timestamp[10];

WiFiClient client;  

/////////////////////////////////////////////////////////////////////////////////////////////////////////
void configModeCallback (WiFiManager *myWiFiManager) {  Serial.println("Entered config mode");             //*-*-*-*-*-*-*-*-*-*-*-*-*-*if control enters this function then net is not connected  Serial.println(WiFi.softAPIP());                  // "WiFi.softAPIP() is for AP" , "WiFi.localIP() is for STA",                                                                  Serial.println(myWiFiManager->getConfigPortalSSID());             //if you used auto generated SSID, print it
}
/////////////////////////////////////// TIMESTAMP CALCULATION function///////////////////////////////////////
int GiveMeTimestamp()
{  unsigned long timeout = millis();
  while (client.available() == 0)  {    if (millis() - timeout > 50000)    {      client.stop();      return 0;    }  }

while (client.available())      {        String line = client.readStringUntil('\r');                    //indexOf() is a funtion to search for smthng , it returns -1 if not found        int pos = line.indexOf("\"timestamp\"");                       //search for "\"timestamp\"" from beginning of response got and copy all data after that , it'll be your timestamp        if (pos >= 0)                                                             {          int j = 0;          for(j=0;j<10;j++)          {            timestamp[j] = line[pos + 12 + j];          }        }      }
}  ////////////////////////////////////////////////////////////////////////////////////////////////////////

void setup() {  Serial.begin(115200);     //(19200,SERIAL_8E1) - data size = 8 bits , parity = Even , stop bit =  1bit  mySerial.begin(115200);  WiFiManager wifiManager;   wifiManager.setAPCallback(configModeCallback);                                                                                                      if(!wifiManager.autoConnect("xxxxxxxxxxxxxx","xxxxxxxxxx")) //you have to change                   //wifiManager.autoConnect("AP-NAME", "AP-PASSWORD"); (OR) wifiManager.autoConnect("AP-NAME"); only ID no password (OR) wifiManager.autoConnect(); this will generate a ID by itself  {    Serial.println("failed to connect and hit timeout");     //control comes here after long time of creating Access point "NodeMCU" by NodeMCU and still it has not connected    //reset and try again, or maybe put it to deep sleep    ESP.reset();    delay(1000);  }   //if you come here you have connected to the WiFi  Serial.println("connected..."); }

void loop() {  int analogValue = analogRead(outputpin);
{   /////////////////////////////////////// SEND THE QUERY AND RECEIVE THE RESPONSE///////////////////////  

        t1=(analogValue/1024.0) *5000;        Serial.print("temp: ");        Serial.println(t1);
        t2=(t1/10);        Serial.print("celc: ");        Serial.println(t2);
        t3=((t2 * 9)/5 + 32);        Serial.print("fhrn: ");        Serial.println(t3);        //break;
            Serial.print("connecting to ");  Serial.println(host);                          //defined upside :- host = devapi2.thethingscloud.com or 139.59.26.117

///////////////////////////////////// TIMESTAMP CODE SNIPPET /////////////////////////
Serial.println("inside get timestamp\n");  if (!client.connect(time_server, httpPort))   {    return;                                                        //*-*-*-*-*-*-*-*-*-*  }
  client.println("GET /api/timestamp HTTP/1.1");                            //Whats this part doing, i didnt get  client.println("Host: baas.thethingscloud.com");  client.println("Cache-Control: no-cache");  client.println("Postman-Token: ea3c18c6-09ba-d049-ccf3-369a22a284b8");  client.println();

GiveMeTimestamp();                        //it'll call the function which will get the timestamp response from the server
Serial.println("timestamp receieved");
Serial.println(timestamp);
///////////////////////////////////////////////////////////////////////////////
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