CAPTCHA for journal subscription

altcha_asset.php

@@ -0,0 +1,24 @@
+<?php
+$url = 'http://127.0.0.1:9000/public/static/altcha.umd.js';
+$context = stream_context_create([
+    'http' => [
+        'method' => 'GET',
+        'timeout' => 6,
+        'ignore_errors' => true,
+        'header' => "User-Agent: MVLog-contact/1.0\r\n",
+    ],
+]);
+$response = @file_get_contents($url, false, $context);
+$status = 0;
+if (isset($http_response_header[0]) && preg_match('/\s(\d{3})\s/', $http_response_header[0], $m)) {
+    $status = (int)$m[1];
+}
+if ($response === false || $status !== 200) {
+    http_response_code(502);
+    header('Content-Type: text/plain; charset=utf-8');
+    echo 'ALTCHA asset unavailable';
+    exit;
+}
+header('Content-Type: application/javascript; charset=utf-8');
+header('Cache-Control: public, max-age=86400');
+echo $response;