Added method to update viewset description (#12218)

* wip

* wip

* updated description on viewset

* fixed model name

* Update schema.py

* Update schema.py

netbox/core/api/schema.py

@@ -13,6 +13,7 @@
     build_choice_field,
     build_media_type_object,
     build_object_type,
+    get_doc,
     is_serializer,
 )
 from drf_spectacular.types import OpenApiTypes
@@ -232,3 +233,31 @@ def _get_request_body(self, direction='request'):
         if request_body_required:
             request_body['required'] = request_body_required
         return request_body
+
+    def get_description(self):
+        """
+        Return a string description for the ViewSet.
+        """
+
+        # If a docstring is provided, use it.
+        if self.view.__doc__:
+            return get_doc(self.view.__class__)
+
+        # When the action method is decorated with @action, use the docstring of the method.
+        action_or_method = getattr(self.view, getattr(self.view, 'action', self.method.lower()), None)
+        if action_or_method and action_or_method.__doc__:
+            return get_doc(action_or_method)
+
+        # Else, generate a description from the class name.
+        return self._generate_description()
+
+    def _generate_description(self):
+        """
+        Generate a docstring for the method. It also takes into account whether the method is for list or detail.
+        """
+        model_name = self.view.queryset.model._meta.verbose_name
+
+        # Determine if the method is for list or detail.
+        if '{id}' in self.path:
+            return f"{self.method.capitalize()} a {model_name} object."
+        return f"{self.method.capitalize()} a list of {model_name} objects."