fix handling of empty publisher names

doab_check/templates/publishers.html

@@ -8,7 +8,7 @@ DOAB Linkchecking by Publisher
 </h2>
 <ul>
 {% for publisher in publisher_list %}
-<li><a href="{%  url 'publisher' publisher.publisher_name %}">
+<li><a href="{%  url 'publisher' publisher.publisher_name|default:'*** no publisher name ***' %}">
 {% if publisher.publisher_name %}{{publisher.publisher_name}}
 {% else %}*** no publisher name ***
 {% endif %}

doab_check/views.py

@@ -48,5 +48,10 @@ class PublisherView(generic.TemplateView):
         publisher = {'publisher': pub}
         publisher_items = Item.objects.filter(publisher_name=pub, status=1)
         publisher['link_count'] = publisher_items.count()
+        if pub == '*** no publisher name ***':
+            pub = ''
+        publisher_items = Item.objects.filter(
+            publisher_name=pub, status=1,
+        )
         
         return {'publisher': publisher, 'items': publisher_items}