make it easier to find and edit ebook editions

frontend/forms.py

@@ -242,7 +242,11 @@ class EditionForm(forms.ModelForm):
         has_goog = self.cleaned_data.get("goog", False) not in nulls
         has_http = self.cleaned_data.get("http", False) not in nulls
         has_doi = self.cleaned_data.get("doi", False) not in nulls
-        if not has_isbn and not has_oclc  and not has_goog and not has_http and not has_doi:
+        try:
+            has_id = self.instance.work.identifiers.all().count() > 0
+        except AttributeError:
+            has_id = False
+        if not has_id and not has_isbn and not has_oclc  and not has_goog and not has_http and not has_doi:
             raise forms.ValidationError(_("There must be either an ISBN, a DOI, a URL or an OCLC number."))
         return self.cleaned_data
     class Meta:

frontend/templates/edition_display.html

@@ -19,6 +19,9 @@
             {% if edition.note %}
                 {{ edition.note }}.<br />
             {% endif %}
+            {% if edition.ebooks.all %}
+                {{ edition.ebooks.all.count }} ebooks<br />
+            {% endif %}
             {% if edition.publisher %}
                 Publisher: <a href="{% url 'bypubname_list' edition.publisher_name.id %}">{{edition.publisher}}</a><br />
             {% endif %}