Add piwik tracking if javascript is disabled

reference #4

hshassets/templatetags/piwik.py

@@ -14,23 +14,26 @@ def piwik_tracking_code():
     if not PIWIK_SITE_ID:
         output = '<!-- no piwik tracking code -->'
     else:
-        output = format_html(PIWIK_TRACKING_SNIPPET, PIWIK_URL, PIWIK_SITE_ID)
+        output = PIWIK_TRACKING_SNIPPET.format(url=PIWIK_URL, site_id=PIWIK_SITE_ID)
 
     return mark_safe(output)
 
 
 PIWIK_TRACKING_SNIPPET = """
-<!-- piwik tracking snippet -->
+<!-- piwik tracking snippet, if javascript is available -->
 <script type="text/javascript">
     var _paq = _paq || [];
     _paq.push(['trackPageView']);
     _paq.push(['enableLinkTracking']);
     (function() {{
-        var u="//{}/";
+        var u="//{url}/";
         _paq.push(['setTrackerUrl', u+'piwik.php']);
-        _paq.push(['setSiteId', '{}']);
+        _paq.push(['setSiteId', '{site_id}']);
         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);
     }})();
 </script>
+
+<!-- if no javascript is available -->
+<noscript><img src="https://{url}/piwik.php?idsite={site_id}&rec=1" style="border:0" alt="" /></noscript>
 """