arangojs: keepNull not an option for collection.save?

Question

I'm going through the documentation for arangojs and looking at the function collection.update(), keepNull is one of the options that can be added. https://github.com/arangodb/arangojs/blob/master/docs/Drivers/JS/Reference/Collection/DocumentManipulation.md

When going through the same documentation for the function collection.save() (https://github.com/arangodb/arangojs/blob/master/docs/Drivers/JS/Reference/Collection/DocumentCollection.md) we find no such option. Why? Do I first need to have an original file, then update that one with keepNull: false before I get it to clean up my documents from any null valued keys? Or is this a lack in the documentation? I think it's correct since I haven't managed to set keepNull to false using collection.save myself.

Answer 1

The driver hands the query options over to the server, so this is the relevant documentation to look at:

https://www.arangodb.com/docs/stable/http/document-working-with-documents.html#create-document

The API does not support keepNull as option when creating a document. It is only available for UPDATE/REPLACE queries to mark attributes for removal. So it's up to you to do this on the client-side. You may open a feature request nonetheless.

BTW. In AQL, UPDATE doc WITH {} OPTIONS { keepNull: false } will not remove any attributes with a null value! It only removes attributes you set explicitly to null in the WITH {} part. This may apply to the driver as well.