ESP8266 ESP-01 DS18B20 SSR MQTT.cpp

//ESP8266 (ESP01) with ESP01 BoB
//MQTT stream temperature data DS18B20 with 1wire on ESP8266 ESP01 and then turn load on/off. perfect for sous vide over the internet.
//shin-ajaran.blogspot.com
#include <ESP8266WiFi.h>
#include <OneWire.h>
#include <DallasTemperature.h>
#include <MQTT.h> //// https://github.com/Imroy/pubsubclient 
#include <PubSubClient.h> //requires a broker that supports version 3.1.1 of the MQTT standard
//Def
#define myPeriodic 15 //in sec | Thingspeak pub is 15sec
#define ONE_WIRE_BUS 2  // DS18B20 on GPIO2
#define mySSR 0  // Solid State Relay on GPIO0

OneWire oneWire(ONE_WIRE_BUS);
DallasTemperature DS18B20(&oneWire);
float prevTemp = 0;
float setPoint = 30;//temperature setpoint used in PID
const char* server = "api.thingspeak.com";
String apiKey ="ZS2IA826R67RJQ77";
const char* MY_SSID = "Edge"; 
const char* MY_PWD = "!1234abcd";
int sent = 0;

//mqtt server IP via node-red 
IPAddress mqttServer(192, 168, 13, 129);//my ubuntu that host mqtt  & nodered

void callback(const MQTT::Publish& pub) {
  // handle msg from topic subscribed to aka on/off the SSR
}

WiFiClient wclient;
PubSubClient edgeSensor(wclient, mqttServer);

void setup() {
  pinMode(mySSR, OUTPUT);
  Serial.begin(115200);
  connectWifi();
  edgeSensor.set_callback(callback);
}

void loop() {
  float temp;
  //char buffer[10];
  DS18B20.requestTemperatures(); 
  temp = DS18B20.getTempCByIndex(0);
  //String tempC = dtostrf(temp, 4, 1, buffer);//handled in sendTemp()
  Serial.print(String(sent)+" Temperature: ");
  Serial.println(temp);
  
  if (temp < setPoint ){
    digitalWrite(mySSR, HIGH);   // turn on the load
  }
  else{
    digitalWrite(mySSR, LOW);   // turn on the load
  }
  
  sendTeperatureTS(temp);
  
  if (!edgeSensor.connected()){
      if (edgeSensor.connect("arduinoClient")){
        edgeSensor.publish("outTopic","hello world");
        edgeSensor.subscribe("inTopic");
      }
    }
    
  int count = myPeriodic;
  while(count--)
  delay(1000);
  if (edgeSensor.connected())
  edgeSensor.loop();

}

void connectWifi()
{
  Serial.print("Connecting to "+*MY_SSID);
  WiFi.begin(MY_SSID, MY_PWD);
  while (WiFi.status() != WL_CONNECTED) {
  delay(1000);
  Serial.print(".");
  }
  
  Serial.println("");
  Serial.println("Connected");
  Serial.println("");  
}//end connect

void sendTeperatureTS(float temp)
{  
   WiFiClient client;
  
   if (client.connect(server, 80)) { // use ip 184.106.153.149 or api.thingspeak.com
   Serial.println("WiFi Client connected ");
   
   String postStr = apiKey;
   postStr += "&field1=";
   postStr += String(temp);
   postStr += "\r\n\r\n";
   
   client.print("POST /update HTTP/1.1\n");
   client.print("Host: api.thingspeak.com\n");
   client.print("Connection: close\n");
   client.print("X-THINGSPEAKAPIKEY: " + apiKey + "\n");
   client.print("Content-Type: application/x-www-form-urlencoded\n");
   client.print("Content-Length: ");
   client.print(postStr.length());
   client.print("\n\n");
   client.print(postStr);
   delay(1000);
   
   }//end if
   sent++;
 client.stop();
}//end send