Wokwi - Online ESP32, STM32, Arduino Simulator

#include <WiFi.h>               
#include <ESPAsyncWebServer.h>
#include <DHT.h>

char index_html[] = R"rawliteral(
<!DOCTYPE html>
<html lang="uk">
  <head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=2.0">
    <title>DHT11 ESP32 AsyncServer</title>
    <style>
      body { font-family: Arial, sans-serif; text-align: center; background: #121212; color: #fff; margin-top: 50px; }
    </style>
  </head>
  <body>
      <h1>DHT11 ESPAsyncWebServer</h1>
      <br>Temperature: <span id="temp">--</span>°C
      <br>Humidity:    <span id="humi">--</span>%
    <script>
      setInterval(() => { fetch('/data') .then(r => r.json()) .then(d => Object.keys(d).forEach(k => { let el = document.getElementById(k); if (el) el.textContent = d[k] || ''; }) ) .catch(e => console.error(e)); }, 1000);
    </script>
  </body> 
</html>
)rawliteral";

#define DHTPIN 13
DHT dht(DHTPIN, DHT11);
AsyncWebServer server(80);

void setup() {
  Serial.begin(115200);
  dht.begin();

  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.print("\nWiFi connected!\nhttps://");
  Serial.println(WiFi.localIP());

  server.on("/data", HTTP_GET, [](AsyncWebServerRequest *request){
    String temp = String(dht.readTemperature());
    String hum =  String(dht.readHumidity());
    String json = "{\"temp\": " + temp + ", \"humi\": " + hum + "}";
    request->send(200, "application/json", json);
  });
  
  server.on("/", HTTP_GET, [](AsyncWebServerRequest *request){
    request->send_P(200, "text/plain", index_html);
  });
  
  server.begin();
}

void loop() {}