php检测域名是否开启https

<?php
function isHttpsEnabled($domain) {
    $url = "http://" . $domain;
    $ch = curl_init($url);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
    curl_setopt($ch, CURLOPT_NOBODY, true);
    curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
    curl_exec($ch);
    $http_code = curl_getinfo($ch, CURLINFO_HTTP_CODE);

    if ($http_code == 200) {
        curl_close($ch);
        $url = "https://" . $domain;
        $ch = curl_init($url);
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
        curl_setopt($ch, CURLOPT_NOBODY, true);
        curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
        curl_exec($ch);
        $https_code = curl_getinfo($ch, CURLINFO_HTTP_CODE);
        curl_close($ch);

        return $https_code == 200;
    }
    curl_close($ch);
    return false;
}

$domain = "example.com";
if (isHttpsEnabled($domain)) {
    echo "$domain 启用了 HTTPS";
} else {
    echo "$domain 未启用 HTTPS";
}
?>