Simple robots.txt for server 404 log

mod/robots_txt.php

@@ -0,0 +1,29 @@
+<?php
+/**
+ * return the default robots.txt
+ * @version 0.1.0
+ */
+
+/**
+ * Simple robots.txt
+ * @inheritdoc (?)
+ */
+function robots_txt_init(App $a) {
+
+    /** @var string[] globally disallowed url */
+    $allDisalloweds=array(
+        '/settings/',
+        '/admin/',
+        '/message/',
+    );
+
+    header("Content-Type: text/plain");
+    echo "User-agent: *\n";
+    echo "Disallow:\n";
+    echo "\n";
+    echo "User-agent: *\n";
+    foreach($allDisalloweds as $disallowed) {
+        echo "Disallow: {$disallowed}\n";
+    }
+    killme();
+}