Send only headers on OPTIONS.

Author: RubenVerborgh

lib/controllers/TimegateController.js

@@ -46,7 +46,13 @@ TimegateController.prototype._handleRequest = function (request, response, next)
   var self = this, timegateMatch = this._matcher.exec(request.url),
       datasource = timegateMatch && timegateMatch[1],
       timemapDetails = datasource && this._timemaps[datasource];
+
+  // Is this resource a well-configured timegate?
   if (timemapDetails) {
+    // For OPTIONS (preflight) requests, send only headers (avoiding expensive lookups)
+    if (request.method === 'OPTIONS')
+      return response.end();
+
     // Try to find the memento closest to the requested date
     var acceptDatetime = toDate(request.headers['accept-datetime']),
         memento = this._getClosestMemento(timemapDetails.timemap, acceptDatetime);