handling the replacement of _paq with piwiks TrackerProxy

Author: joernroeder

index.js

@@ -55,6 +55,15 @@ var PiwikTracker = function(opts) {
 
 		var hasSiteId = false;
 		var hasTrackerUrl = false;
+
+		if (window._paq.length === undefined) {
+			// piwik seems to have replaced the array by it's TrackerProxy
+			// @see https://github.com/piwik/piwik/blob/3.x-dev/js/piwik.js#L7050
+			// @see https://github.com/piwik/piwik/blob/3.x-dev/js/piwik.js#L7115
+			// we should be good to go.
+			return true;
+		}
+
 		for (var j = 0, l = window._paq.length; j < l; j++) {
 			if (~window._paq[j].indexOf('setSiteId')) {
 				hasSiteId = true

test/client.tests.js

@@ -622,7 +622,36 @@ describe('piwik-react-router client tests', function () {
       });
 
       assert.isFalse(warningSpy.called);
+    });
+
+    it ('should not warn about a missing siteId if opts.injectScript is disabled and the external piwik script has replaced _paq with the TrackerProxy', () => {
+      let warningSpy = sinon.spy();
+      let trackerProxySpy = sinon.spy();
 
+      // instantiating piwik
+      (function() {
+        var u='http://foo.bar/';
+
+        // simulate piwiks TrackerProxy replacement
+        // @see https://github.com/piwik/piwik/blob/3.x-dev/js/piwik.js#L7115
+        window._paq = {
+          push: trackerProxySpy
+        };
+        window._paq.push(['setTrackerUrl', u+'piwik.php']);
+        window._paq.push(['setSiteId', 1]);
+        var d=document, g=d.createElement('script'), s=d.getElementsByTagName('script')[0];
+        g.type='text/javascript'; g.async=true; g.defer=true; g.src=u+'piwik.js'; s.parentNode.insertBefore(g,s);
+      })();
+
+      const piwikReactRouter = testUtils.requireNoCache('../', {
+        'warning': warningSpy
+      })({
+        url: 'foo.bar',
+        injectScript: false
+      });
+
+      assert.isFalse(warningSpy.called);
+      assert.isTrue(trackerProxySpy.called);
     });
 
     it ('should not inject piwik.js twice if multiple piwicReactRouter intances are created', () => {