public override IEnumerable <ValidationMessage> GetValidationMessages(Dictionary <string, Dictionary <string, Operation> > entity, RuleContext context) { // get all operation objects that are either of get or post type ServiceDefinition serviceDefinition = (ServiceDefinition)context.Root; var listOperations = entity.Values.SelectMany(opDict => opDict.Where(pair => pair.Key.ToLower().Equals("get") || pair.Key.ToLower().Equals("post"))); foreach (var opPair in listOperations) { // if the operation id is not of type _list* or does not return an array type, skip if (!ListRegex.IsMatch(opPair.Value.OperationId) || !ValidationUtilities.IsXmsPageableOperation(opPair.Value)) { continue; } string collType = opPair.Value.Responses["200"]?.Schema?.Reference?.StripDefinitionPath(); // if no response type defined skip if (collType == null) { continue; } var collTypeDef = serviceDefinition.Definitions[collType]; // if collection object has 2 properties or less (x-ms-pageable objects can have the nextlink prop) // and the object does not have a property named "value", show the warning if ((collTypeDef.Properties?.Count <= 2) && collTypeDef.Properties.All(prop => !(prop.Key.ToLower().Equals("value") && prop.Value.Type == DataType.Array))) { yield return(new ValidationMessage(new FileObjectPath(context.File, context.Path), this, collType, opPair.Value.OperationId)); } } }