[Rspamd] Use meta exporter to pipe meta data of ratelimited msg to Redis

data/conf/rspamd/local.d/metadata_exporter.conf

@@ -1,10 +1,26 @@
 rules {
-        QUARANTINE {
-                backend = "http";
-                url = "http://nginx:9081/pipe.php";
-                selector = "is_reject";
-                formatter = "default";
-                meta_headers = true;
-        }
+  QUARANTINE {
+    backend = "http";
+    url = "http://nginx:9081/pipe.php";
+    selector = "is_reject";
+    formatter = "default";
+    meta_headers = true;
+  }
+	RLINFO {
+		backend = "http";
+		url = "http://nginx:9081/pipe_rl.php";
+		selector = "ratelimited";
+		formatter = "json";
+	}
+}
+custom_select {
+  ratelimited = <<EOD
+return function(task)
+  local ratelimited = task:get_symbol("RATELIMITED")
+  if ratelimited then
+    return true
+  end
+  return
+end
+EOD;
 }
-

data/conf/rspamd/meta_exporter/pipe_rl.php

@@ -0,0 +1,38 @@
+<?php
+// File size is limited by Nginx site to 10M
+// To speed things up, we do not include prerequisites
+header('Content-Type: text/plain');
+require_once "vars.inc.php";
+// Do not show errors, we log to using error_log
+ini_set('error_reporting', 0);
+// Init Redis
+$redis = new Redis();
+$redis->connect('redis-mailcow', 6379);
+
+$raw_data_content = file_get_contents('php://input');
+$raw_data_decoded = json_decode($raw_data_content, true);
+
+$data['time'] = time();
+$data['rcpt'] = implode(', ', $raw_data_decoded['rcpt']);
+$data['from'] = $raw_data_decoded['from'];
+$data['user'] = $raw_data_decoded['user'];
+$symbol_rl_key = array_search('RATELIMITED', array_column($raw_data_decoded['symbols'], 'name'));
+$data['rl_info'] = implode($raw_data_decoded['symbols'][$symbol_rl_key]['options']);
+preg_match('/(.+)\((.+)\)/i', $data['rl_info'], $rl_matches);
+if (!empty($rl_matches[1]) && !empty($rl_matches[2])) {
+  $data['rl_name'] = $rl_matches[1];
+  $data['rl_hash'] = $rl_matches[2];
+}
+else {
+  $data['rl_name'] = 'err';
+  $data['rl_hash'] = 'err';
+}
+$data['qid'] = $raw_data_decoded['qid'];
+$data['ip'] = $raw_data_decoded['ip'];
+$data['message_id'] = $raw_data_decoded['message_id'];
+$data['header_subject'] = implode(' ', $raw_data_decoded['header_subject']);
+$data['header_from'] = implode(', ', $raw_data_decoded['header_from']);
+
+$redis->lpush('RL_LOG', json_encode($data));
+exit;
+