如何正确地使用ESP8266向IFTTT Webhook服务发出POST请求？

#include <ESP8266WiFi.h>
#include <ESP8266HTTPClient.h>

const char* ssid = "your_SSID";
const char* password = "your_PASSWORD";

const char* event = "your_EVENT";  // IFTTT触发器的事件名称
const char* apiKey = "your_API_KEY";  // IFTTT账号的API密钥

void setup() {
  Serial.begin(115200);
  WiFi.begin(ssid, password);
  
  while (WiFi.status() != WL_CONNECTED) {
    delay(1000);
    Serial.println("Connecting to WiFi...");
  }
  Serial.println("Connected to WiFi");
}

void loop() {
  if (WiFi.status() == WL_CONNECTED) {
    HTTPClient http;
    
    // 构建IFTTT Webhook服务的URL
    String url = "http://maker.ifttt.com/trigger/";
    url += event;
    url += "/with/key/";
    url += apiKey;
    
    http.begin(url);
    http.addHeader("Content-Type", "application/json");  // 设置请求头
    
    // 构建要发送的数据
    String payload = "{\"value1\":\"data1\",\"value2\":\"data2\",\"value3\":\"data3\"}";
    
    int httpResponseCode = http.POST(payload);  // 发送POST请求
    
    if (httpResponseCode > 0) {
      String response = http.getString();
      Serial.println(httpResponseCode);
      Serial.println(response);
    } else {
      Serial.print("Error on sending request. Error code: ");
      Serial.println(httpResponseCode);
    }
    
    http.end();
  }
  
  delay(5000);  // 等待一段时间后再次发送请求
}