[debug] if ES cluster in stage/prod ever returns 408

middleware/500.js

@@ -5,7 +5,7 @@ function middleware(err, req, res, next) {
   logger.error( 'Error: `%s`. Stack trace: `%s`.', err, err.stack );
   res.header('Cache-Control','no-cache');
   if( res.statusCode < 400 ){ res.status(500); }
-  res.json({ error: err && typeof err.message === 'string' ? err.message : 'internal server error' });
+  res.json({ error: res.statusCode + ':' + (err && typeof err.message === 'string' ? err.message : 'internal server error' )});
 }
 
 module.exports = middleware;