I want to ensure that all documents of a certain doc_type have a "updatedAt" timestamp (ISO 8601) that gets updated whenever the document is updated. It needs to be a server-side timestamp as I don't know if I can trust that all of the clients times are in sync.
I use an ingest pipeline to add "createdAt" timestamps, but it seems that pipelines are not supported using the update API.
I've tried using update scripts (using the newly available 'ctx._now' value), but cannot get the parsing into ISO 8601 working. Further, I'm not sure that update scripts are the most maintainable way of doing this since every update type would require a custom script.