ESP32 Toggle Onboard LED Web Server

/*
You can toggle the onboard LED through a simple web server using your network. The ESP32 will host a web page with a button to turn the LED ON or OFF.

Upload this code to your ESP32, and replace "your_SSID" and "your_PASSWORD" with your WiFi network credentials. After uploading, open the Serial Monitor, and note the IP address assigned to the ESP32. Open a web browser and enter the IP address. You should see a web page with a "Toggle LED" button. Press the button to toggle the onboard LED.

The code sets up a simple web server using the ESPAsyncWebServer library (https://github.com/me-no-dev/ESPAsyncWebServer). If you haven't already, install the library using the Arduino Library Manager or download it from the link provided. Also, install the "AsyncTCP" library (https://github.com/me-no-dev/AsyncTCP) as it is a dependency for the ESPAsyncWebServer library when using an ESP32.

The web server serves an HTML page containing a button to toggle the LED. When the button is clicked, a request is sent to the "/toggle" endpoint, which toggles the LED's state.
*/

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

// WiFi credentials
const char* ssid = "your_SSID";
const char* password = "your_PASSWORD";

// GPIO pin definitions
const int ledPin = 2; // Built-in LED pin

AsyncWebServer server(80);

// HTML for the web page
const char index_html[] PROGMEM = R"rawliteral(
<!DOCTYPE html>
<html>
<head>
  <title>ESP32 LED Control</title>
  <style>
    html {font-family: Arial; display: inline-block; text-align: center;}
    h2 {font-size: 3.0rem;}
    p {font-size: 1.5rem;}
    button {background-color: #4CAF50; border: none; color: white; padding: 16px 40px; text-align: center; text-decoration: none; display: inline-block; font-size: 30px; margin: 4px 2px; cursor: pointer;}
  </style>
</head>
<body>
  <h2>ESP32 Web Server - LED Control</h2>
  <p><button onclick="toggleLED()">Toggle LED</button></p>
  <script>
    async function toggleLED() {
      const response = await fetch("/toggle");
    }
  </script>
</body>
</html>
)rawliteral";

void setup() {
  Serial.begin(115200);
  delay(1000);

  // Configure LED pin as OUTPUT
  pinMode(ledPin, OUTPUT);

  // Connect to WiFi
  Serial.println("Connecting to WiFi...");
  WiFi.begin(ssid, password);

  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }

  Serial.println("");
  Serial.println("WiFi connected");
  Serial.print("IP address: ");
  Serial.println(WiFi.localIP());

  // Serve the HTML page
  server.on("/", HTTP_GET, [](AsyncWebServerRequest *request){
    request->send_P(200, "text/html", index_html);
  });

  // Handle LED toggle request
  server.on("/toggle", HTTP_GET, [](AsyncWebServerRequest *request){
    digitalWrite(ledPin, !digitalRead(ledPin));
    request->send(200, "text/plain", "Toggled");
  });

  // Start the server
  server.begin();
}

void loop() {
}