The source from which to derive the index or snapshot age. Can be one of name, creation_date, or field_stats.

nameedit

Setting source to name tells Curator to derive an epoch timestamp from an index or snapshot name based on a timestring. This was the only available behavior in previous versions of Curator.

This source requires timestring to be set, in addition to direction, unit, and unit_count.

creation_dateedit

Setting source to creation_date tells Curator to reference the index or snapshot creation time, as stored in the cluster metadata.

This source requires direction, unit, and unit_count.

field_statsedit

Setting source to field_stats tells Curator to use a newer Elasticsearch API call which returns the minimum and maximum value of a field in an index. Curator will only use timestamp fields, which should be mapped in Elasticsearch as type date.

The field and stats_result settings are required to use the field_stats source.