proper filenames for originals and archived documents

src/documents/models.py

@@ -241,6 +241,10 @@ class Document(models.Model):
     def file_name(self):
         return slugify(str(self)) + self.file_type
 
+    @property
+    def archive_file_name(self):
+        return slugify(str(self)) + ".pdf"
+
     @property
     def file_type(self):
         return mimetypes.guess_extension(str(self.mime_type))