Include feedback URL QR code on the callforpapers page

This makes it easy for speakers to include the feedback QR
code in their slides

Author: ssinger

postgresqleu/confreg/views.py

@@ -1939,6 +1939,12 @@ def callforpapers_edit(request, confname, sessionid):
             slidesurlform = SessionSlidesUrlForm()
             slidesfileform = SessionSlidesFileForm()
 
+        feedbackqrcode = None
+        if session.status in (1, 4):
+            # 1 = confirmed, so render
+            # 4 = reserve, so render
+            feedbackqrcode = generate_base64_qr('{0}/events/{1}/feedback/{2}/'.format(settings.SITEBASE, confname, session.id), None, 300)
+
         return render_conference_response(request, conference, 'cfp', 'confreg/session_feedback.html', {
             'session': session,
             'feedbackcount': feedbackcount,
@@ -1949,6 +1955,7 @@ def callforpapers_edit(request, confname, sessionid):
             'slidesurlform': slidesurlform,
             'slidesfileform': slidesfileform,
             'slides': ConferenceSessionSlides.objects.filter(session=session),
+            'feedbackqrcode': feedbackqrcode,
             })
 
     if session.id:

template.jinja/confreg/session_feedback.html

@@ -50,8 +50,19 @@ <h2>Slides</h2>
 <input type="submit" name="submit" value="Upload slides">
 </form>
 
-{%if feedbackcount%}
+{% if feedbackcount or feedbackqrcode %}
 <h2>Feedback</h2>
+
+{% if feedbackqrcode %}
+<h3>Feedback link</h3>
+<p>
+Attendees will be able to leave <a href="/events/{{conference.urlname}}/feedback/{{session.id}}/">feedback</a> on your talk.
+This link will work once your talk has started.  You can include the below QR code in your slides to increase the response rate.
+</p>
+<p class="feedback-qrcode"><img src="data:image/png;base64,{{ feedbackqrcode }}"></p>
+{%endif%}
+
+{%if feedbackcount%}
 {%if conference.feedbackopen%}
 <h3>Preliminary feedback!</h3>
 <p>
@@ -105,6 +116,7 @@ <h5>{{f.title}}</h5>
 {%endfor%}
 {%endif%}
 
+{%endif%}
 {%endif%}
 {%endblock%}