indico-plugins/piwik/indico_piwik/templates/tracking.html

<!-- Piwik -->
<script>
    (function() {
        'use strict';

        var url = '//{{ server_url }}';
        var g = document.createElement('script');
        var s = document.getElementsByTagName('script')[0];
        g.type = 'text/javascript';
        g.defer = true;
        g.async = true;
        g.src = url + 'piwik.js';
        g.onload = init_tracking;
        s.parentNode.insertBefore(g, s);

        function init_tracking() {
            try {
                track_site();
                {% if event_id is defined %}
                    track_event();
                {% endif %}
            } catch(err) {}
        }

        function track_site() {
            var general_tracker = Piwik.getTracker(url + 'piwik.php', {{ site_id_general }});
            general_tracker.enableLinkTracking();
            general_tracker.trackPageView();
        }

        {% if event_id is defined %}
            function track_event() {
                var event_tracker = Piwik.getTracker(url + 'piwik.php', {{ site_id_events }});
                event_tracker.enableLinkTracking();
                event_tracker.setCustomVariable(1, 'Conference', '{{ event_id }}', 'page');
                {% if contrib_id is defined %}
                    event_tracker.setCustomVariable(2, 'Contribution', '{{ contrib_id }}', 'page');
                {% endif %}
                event_tracker.trackPageView();
            }
        {% endif %}
    })();
</script>
<!-- End Piwik Code -->