docs: add missing docs on the `transformer` param to RrdQueryDsProxy

1 files changed, 2 insertions, 0 deletions

diff --git a/jarmon/jarmon.js b/jarmon/jarmon.js
index fba8ceb..126671e 100644
--- a/jarmon/jarmon.js
+++ b/jarmon/jarmon.js
@@ -407,6 +407,8 @@ jarmon.RrdQueryRemote.prototype.getDSNames = function() {
  * @constructor
  * @param rrdQuery {jarmon.RrdQueryRemote} An RrdQueryRemote instance
  * @param dsId {(string|number)} identifier of the RRD datasource (string or number)
+ * @param {function} [transformer=function(v){return v}] A callable which
+ *      performs a transformation of the values returned from the RRD file.
  **/
 jarmon.RrdQueryDsProxy = function(rrdQuery, dsId, transformer) {
     this.rrdQuery = rrdQuery;