sensors/temperature/DS18B20.ino

#include <ESP8266WiFi.h>
#include <ESP8266mDNS.h>
#include <ESP8266WebServer.h>
#include <OneWire.h>
#include <DallasTemperature.h>

#define ONE_WIRE_BUS 2

const char* type = "temperature";
const char* location = "xxx";

const char* ssid     = "xxx"; // Your ssid
const char* password = "xxx"; // Your Password

OneWire oneWire(ONE_WIRE_BUS);
DallasTemperature sensors(&oneWire);
ESP8266WebServer server(80);

void setup() {
  // Connect to WiFi network
  
  WiFi.begin(ssid, password);
  
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
  }

  MDNS.begin((String)"sensor-" + type + "-" + location);

  sensors.begin();
  
  // Start the server

  server.on("/temperature/celcius", [](){
    server.send(200, "application/json", getCelcius());
  });
  
  server.begin();
}

String getCelcius() {
  //get the temperature in celcius

  sensors.requestTemperatures();

  float temp = sensors.getTempCByIndex(0);

  return "{\"temperature\":" + String(temp) + ", \"location\": \"" + location + "\", \"type\":\"" + type + "\"}";
}

void loop(){
  server.handleClient();
}