elasticsearch-js/docs/reference/api/TransformTimeSync.md

Interface TransformTimeSync

Name	Type	Description
delay	Duration	The time delay between the current time and the latest input data time.
field	Field	The date field that is used to identify new documents in the source. In general, it’s a good idea to use a field that contains the ingest timestamp. If you use a different field, you might need to set the delay such that it accounts for data transmission delays.