Make GA integration work with named trackers

allow configuring ga tracker name and add some tests
add ga spec
coding style updates
update prefixedSend usage
use trackerSend instead of prefixedSend
fix tests

fix trackerSend undefined error - @protonate

src/ga.js

@@ -19,6 +19,7 @@ var _category = 'Prebid.js Bids';
 var _eventCount = 0;
 var _enableDistribution = false;
 var _timedOutBidders = [];
+var _trackerSend = null;
 
 /**
  * This will enable sending data to google analytics. Only call once, or duplicate data will be sent!
@@ -33,6 +34,8 @@ exports.enableAnalytics = function (gaOptions) {
     _gaGlobal = 'ga';
   }
 
+  _trackerSend = gaOptions.trackerName ? gaOptions.trackerName + '.send' : 'send';
+
   if (typeof gaOptions.enableDistribution !== 'undefined') {
     _enableDistribution = gaOptions.enableDistribution;
   }
@@ -88,6 +91,10 @@ exports.enableAnalytics = function (gaOptions) {
   });
 };
 
+exports.getTrackerSend = function getTrackerSend() {
+  return _trackerSend;
+};
+
 /**
  * Check if gaGlobal or window.ga is defined on page. If defined execute all the GA commands
  */
@@ -178,7 +185,7 @@ function sendBidRequestToGa(bid) {
   if (bid && bid.bidderCode) {
     _analyticsQueue.push(function () {
       _eventCount++;
-      window[_gaGlobal]('send', 'event', _category, 'Requests', bid.bidderCode, 1, _disibleInteraction);
+      window[_gaGlobal](_trackerSend, 'event', _category, 'Requests', bid.bidderCode, 1, _disibleInteraction);
     });
   }
 
@@ -195,19 +202,19 @@ function sendBidResponseToGa(bid) {
       if (typeof bid.timeToRespond !== 'undefined' && _enableDistribution) {
         _eventCount++;
         var dis = getLoadTimeDistribution(bid.timeToRespond);
-        window[_gaGlobal]('send', 'event', 'Prebid.js Load Time Distribution', dis, bidder, 1, _disibleInteraction);
+        window[_gaGlobal](_trackerSend, 'event', 'Prebid.js Load Time Distribution', dis, bidder, 1, _disibleInteraction);
       }
 
       if (bid.cpm > 0) {
         _eventCount = _eventCount + 2;
         var cpmDis = getCpmDistribution(bid.cpm);
         if (_enableDistribution) {
           _eventCount++;
-          window[_gaGlobal]('send', 'event', 'Prebid.js CPM Distribution', cpmDis, bidder, 1, _disibleInteraction);
+          window[_gaGlobal](_trackerSend, 'event', 'Prebid.js CPM Distribution', cpmDis, bidder, 1, _disibleInteraction);
         }
 
-        window[_gaGlobal]('send', 'event', _category, 'Bids', bidder, cpmCents, _disibleInteraction);
-        window[_gaGlobal]('send', 'event', _category, 'Bid Load Time', bidder, bid.timeToRespond, _disibleInteraction);
+        window[_gaGlobal](_trackerSend, 'event', _category, 'Bids', bidder, cpmCents, _disibleInteraction);
+        window[_gaGlobal](_trackerSend, 'event', _category, 'Bid Load Time', bidder, bid.timeToRespond, _disibleInteraction);
       }
     });
   }
@@ -223,7 +230,7 @@ function sendBidTimeouts(bid) {
       utils._each(_timedOutBidders, function (bidderCode) {
         if (bid.bidder === bidderCode) {
           _eventCount++;
-          window[_gaGlobal]('send', 'event', _category, 'Timeouts', bidderCode, bid.timeToRespond, _disibleInteraction);
+          window[_gaGlobal](_trackerSend, 'event', _category, 'Timeouts', bidderCode, bid.timeToRespond, _disibleInteraction);
         }
       });
     });
@@ -236,7 +243,7 @@ function sendBidWonToGa(bid) {
   var cpmCents = convertToCents(bid.cpm);
   _analyticsQueue.push(function () {
     _eventCount++;
-    window[_gaGlobal]('send', 'event', _category, 'Wins', bid.bidderCode, cpmCents, _disibleInteraction);
+    window[_gaGlobal](_trackerSend, 'event', _category, 'Wins', bid.bidderCode, cpmCents, _disibleInteraction);
   });
 
   checkAnalytics();

test/spec/ga_spec.js

@@ -0,0 +1,28 @@
+var assert = require('assert');
+var ga = require('../../src/ga');
+
+describe('Ga', function () {
+
+  describe('enableAnalytics', function () {
+
+    it('should accept a tracker name option and output prefixed send string', function () {
+      var options = { trackerName: 'foo' };
+      ga.enableAnalytics(options);
+
+      var output = ga.getTrackerSend();
+      assert.equal(output, 'foo.send');
+    });
+
+
+    it('should output normal send string when trackerName is not set', function () {
+      var options = {};
+      ga.enableAnalytics(options);
+
+      var output = ga.getTrackerSend();
+      assert.equal(output, 'send');
+    });
+
+  });
+
+
+});