add exchange

samples/parse-records.js

@@ -34,6 +34,9 @@ file.trim().split(/\n/).forEach(function (line) {
   if (/^(TXT)$/.test(type)) {
     data = [ thing ];
   }
+  if (/^(MX)$/.test(type)) {
+    exchange = thing;
+  }
   if (/^(MX|SRV)$/.test(type)) {
     priority = json.priority || 10;
   }