Prevent element_corpus update + Disable Element creation in admin panel

arkindex/documents/admin.py

@@ -71,10 +71,14 @@ class ElementAdmin(admin.ModelAdmin):
     list_display = ('id', 'name', 'type', 'corpus', )
     list_filter = ['type__slug', 'corpus']
     fields = ('id', 'type', 'name', 'corpus')
-    readonly_fields = ('id', )
+    readonly_fields = ('id', 'corpus', )
     search_fields = ('name', )
     inlines = (MetaDataInline, ClassificationInline)
 
+    # Disable element creation through the admin to prevent element_type conflicts
+    def has_add_permission(self, request):
+        return False
+
     def formfield_for_foreignkey(self, db_field, request, **kwargs):
         if db_field.name == 'type':
             # Only display types available on the element's corpus