在Google Analytics 4中用reCAPTCHA v3识别虚假流量

const ALLOWED_ORIGIN = "https://www.ichdata.com"; //域名要换成你自己的

function corsHeaders() {
  return {
    "Access-Control-Allow-Origin": ALLOWED_ORIGIN,
    "Access-Control-Allow-Methods": "POST, OPTIONS",
    "Access-Control-Allow-Headers": "Content-Type",
    "Content-Type": "application/json; charset=UTF-8",
    "Cache-Control": "no-store"
  };
}

function send(data, status) {
  return new Response(JSON.stringify(data), {
    status,
    headers: corsHeaders()
  });
}

export default {
  async fetch(request, env) {
    if (request.method === "OPTIONS") {
      return new Response(null, {
        status: 204,
        headers: corsHeaders()
      });
    }

    if (request.method !== "POST") {
      return send({
        success: false,
        error: "method_not_allowed"
      }, 405);
    }

    try {
      const body = await request.json();
      const token = body.token;

      if (!token) {
        return send({
          success: false,
          error: "token_missing"
        }, 400);
      }

      const googleResponse = await fetch(
        "https://www.google.com/recaptcha/api/siteverify",
        {
          method: "POST",
          headers: {
            "Content-Type": "application/x-www-form-urlencoded"
          },
          body: new URLSearchParams({
            secret: env.RECAPTCHA_SECRET,
            response: token
          })
        }
      );

      const result = await googleResponse.json();

      const valid =
        result.success === true &&
        result.action === "visitor_check" &&
        (
          result.hostname === "www.ichdata.com" ||
          result.hostname === "ichdata.com"
        );

      return send({
        success: valid,
        score: result.score ?? null,
        action: result.action ?? null,
        hostname: result.hostname ?? null,
        google_errors: result["error-codes"] ?? []
      }, 200);

    } catch (error) {
      console.error("Worker error:", error);

      return send({
        success: false,
        error: "worker_exception"
      }, 500);
    }
  }
};

<script>
(function () {
  var siteKey = '******';  // 改用你实际的

  var verifyEndpoint =
    'https://ichdata-recaptcha.haran-huang.workers.dev/recaptcha-visitor';   // 改用你实际的

  function loadRecaptcha(callback) {
    if (window.grecaptcha) {
      callback();
      return;
    }

    var script = document.createElement('script');

    script.src =
      'https://www.google.com/recaptcha/api.js?render=' +
      encodeURIComponent(siteKey);

    script.async = true;
    script.onload = callback;

    document.head.appendChild(script);
  }

  loadRecaptcha(function () {
    grecaptcha.ready(function () {
      grecaptcha.execute(siteKey, {
        action: 'visitor_check'
      }).then(function (token) {
        fetch(verifyEndpoint, {
          method: 'POST',
          headers: {
            'Content-Type': 'application/json'
          },
          body: JSON.stringify({
            token: token,
            page: location.href,
            path: location.pathname
          })
        })
        .then(function (response) {
          console.log('Worker status:', response.status);

          return response.text();
        })
        .then(function (text) {
          console.log(
            'Worker raw response:',
            JSON.stringify(text)
          );

          if (!text) {
            console.error('Worker returned an empty response');
            return;
          }

          var data;

          try {
            data = JSON.parse(text);
          } catch (error) {
            console.error(
              'Worker response is not valid JSON:',
              error
            );
            return;
          }

          window.dataLayer = window.dataLayer || [];

          window.dataLayer.push({
            event: 'recaptcha_verified',

            recaptcha_success: data.success === true,
            recaptcha_score: data.score,
            recaptcha_action: data.action,
            recaptcha_hostname: data.hostname,
            recaptcha_risk:
              data.score !== null &&
              data.score < 0.3
                ? 'high'
                : 'normal',

            recaptcha_page: location.href,
            recaptcha_path: location.pathname
          });

          console.log(
            'reCAPTCHA dataLayer event pushed:',
            data
          );
        })
        .catch(function (error) {
          console.error(
            'Worker request failed:',
            error
          );
        });
      });
    });
  });
})();
</script>