bài tập CSDL - Wokwi ESP32, STM32, Arduino Simulator

//CSDL
#include <WiFi.h>
#include "PubSubClient.h"
#include "DHT.h"
#define DHTPIN 4
#define DHTTYPE DHT22 
String data_send;

const char * MQTTServer = "broker.hivemq.com";
const char * MQTT_Topic = "VLUTE/DHT22";

// Tạo ID ngẫu nhiên tại: https://www.guidgen.com/
const char * MQTT_ID = "15d34c88-2da1-470c-bee5-cc9397273cd9";
int Port = 1883;

WiFiClient espClient;
PubSubClient client(espClient);
DHT dht(DHTPIN, DHTTYPE);

void WIFIConnect() {
  Serial.println("Connecting to SSID: Wokwi-GUEST");
  WiFi.begin("Wokwi-GUEST", "");
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("");
  Serial.print("WiFi connected");
  Serial.print(", IP address: ");
  Serial.println(WiFi.localIP());
}

void MQTT_Reconnect() {
  while (!client.connected()) {
    if (client.connect(MQTT_ID)) {
      Serial.print("MQTT Topic: ");
      Serial.print(MQTT_Topic);
      Serial.print(" connected");
      client.subscribe(MQTT_Topic);
      Serial.println("");
    } else {
      Serial.print("failed, rc=");
      Serial.print(client.state());
      Serial.println(" try again in 5 seconds");
      delay(5000);
    }
  }
}

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

  WIFIConnect();
  client.setServer(MQTTServer, Port);
  dht.begin();
}

void loop() {
  delay(10);
  if (!client.connected()) {
    MQTT_Reconnect();
  }else{
    publishDHT22();
  }
  client.loop();
}

void publishDHT22(){

    float h = dht.readHumidity();
    float t = dht.readTemperature();
    float tong = 0 ;
    for(int i=1; i <=3 ; i++){
      tong = tong + t;
    }
    int str ;
    if(h > 85){
       str = 1;
    }else{
       str = 0;
    }
    float tb_tong = tong/3;
    data_send = "{\"temp_value\":\"" + String(t) + "\",\"press_value\":\"" + String(h) + "\",\"tb_value\":\"" + String(tb_tong) + "\",\"str_value\":\"" + String(str) + "\"}";
    Serial.println(data_send);
    client.publish(MQTT_Topic, String(data_send).c_str()); 
}
// <!DOCTYPE html>
// <html lang="en">
// <head>
//     <meta charset="UTF-8">
//     <meta name="viewport" content="width=device-width, initial-scale=1.0">
//     <title>Document</title>
//     <script src="https://cdnjs.cloudflare.com/ajax/libs/paho-mqtt/1.0.1/mqttws31.min.js" type="text/javascript"></script>
//     <script src="https://code.jquery.com/jquery-3.6.0.min.js"></script>
//     <script src="https://cdn.jsdelivr.net/npm/chart.js"></script>

// </head>
// <body>
//     <p>Nhiệt độ: <span id="nhietdo"></span></p>
//     <p>Độ ẩm: <span id="doam"></span></p>

//     <canvas id="myChart"></canvas>

//     <form action="" method="get">
//         <input type="hidden" name="temp" id="temp">
//         <br>
//         <input type="hidden" name="humi" id="humi">
//         <br>
//     </form>
// </body>
// </html>
// <script>
    
//     client = new Paho.MQTT.Client("broker.hivemq.com", Number(8000), "");

//     client.onConnectionLost = onConnectionLost;
//     client.onMessageArrived = onMessageArrived;

//     client.connect({onSuccess:onConnect});

//     function onConnect() {
//     console.log("onConnect");
//     client.subscribe("VLUTE/DHT22");
//     }

//     function onConnectionLost(responseObject) {
//     if (responseObject.errorCode !== 0) {
//         console.log("onConnectionLost:"+responseObject.errorMessage);
//     }
//     }

//     function onMessageArrived(message) {
//     console.log("onMessageArrived:"+message.payloadString);
//     var data = JSON.parse(message.payloadString);
//     document.getElementById("nhietdo").innerHTML = data.temp_value;
//     document.getElementById("doam").innerHTML = data.press_value;

//     document.getElementById("temp").value = data.temp_value;
//     document.getElementById("humi").value = data.press_value;

//     $.get("", {temp: data.temp_value, humi: data.press_value}, function(response){
//         console.log("Insert thành công");
//     }).fail(function(xhr, status, error) { 
//         console.error("Error:" + status + " " + error);
//         console. log(xhr.responseText);
//     });
// }

//  // Hàm cập nhật biểu đồ
//     function updateChart(timestamp, temp, humi) {
//         myChart.data.labels.push(timestamp);
//         myChart.data.datasets[0].data.push(temp);
//         myChart.data.datasets[1].data.push(humi);
//         myChart.update();
//         }
// </script>

// <?php
// $servername = "localhost";
// $username = "root";
// $password = "";
// $dbname = "dht";

// // Create connection
// $conn = mysqli_connect($servername, $username, $password, $dbname);

// // Check connection
// if (!$conn) { 
// 	die("Connection failed: " . mysqli_connect_error()); 
// } 
// echo "Database connection is OK<br>"; 
// if($_SERVER["REQUEST_METHOD"] == isset($_GET["temp"]) && isset($_GET["humi"])) {
// 	$t = $_GET["temp"];
// 	$h = $_GET["humi"];
// 	$sql = "INSERT INTO dht2 (nhietdo, doam) VALUES (".$t.", ".$h.")"; 
// 	if (mysqli_query($conn, $sql)) { 
// 		echo "\nNew record created successfully"; 
// 	} else { 
// 		echo "Error: " . $sql . "<br>" . mysqli_error($conn); 
// 	}
// }
// ?>