ESP 8266 / DHT22 simple webserver

#include "DHT.h"
#include <ESP8266WiFi.h>
#include <ESP8266WebServer.h>

#define DHTPIN 5
#define DHTTYPE DHT22
#define RATE 115200
#define DEBUG true

#define SSID "szvsyGm6E74c6HnevvfBHuuY6NG3otjOyxBpEyb9"
#define PASS "szvsyGm6E74c6HnevvfBHuuY6NG3otjOyxBpEyb9"

DHT myDht(DHTPIN, DHTTYPE);
ESP8266WebServer server(80);

void setup() {
  myDht.begin();
  if (DEBUG == true) {
    Serial.begin(RATE);
    Serial.println("");
    Serial.println("Connecting to WiFI");
  }

  WiFi.begin(SSID, PASS);

  while (WiFi.status() != WL_CONNECTED) {
    delay(10);
    if (DEBUG == true) {
      Serial.print(".");
    }
  }
  if (DEBUG == true) {
    Serial.println("");
    Serial.println("Connected");
    Serial.println(WiFi.localIP());
  }

  server.on("/measurement", HTTP_GET, returnMeasurement);
  server.begin();
  if (DEBUG == true) {
    Serial.println("HTTP server started");
  }
}

void returnMeasurement() {
  if (DEBUG == true) {
    Serial.println("GET on /measurement");
  }
  float temperature = myDht.readTemperature();
  float humidity    = myDht.readHumidity();
  float heatIndex   = myDht.computeHeatIndex(temperature, humidity, false);
  String json       = "{\"temperature\":" + String(temperature) + ",\"humidity\":" + String(humidity) + ",\"heatIndex\":" + String(heatIndex) + "}";
  server.send(200, "application/json", json);
}

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