indices.flush

force

Boolean — Whether a flush should be forced even if it is not necessarily needed ie. if no changes will be committed to the index. This is useful if transaction log IDs should be incremented even if no uncommitted changes are present. (This setting can be considered as internal)

waitIfOngoing

Boolean — If set to true the flush operation will block until the flush can be executed if another flush operation is already executing. The default is true. If set to false the flush will be skipped iff if another flush operation is already running.

ignoreUnavailable

Boolean — Whether specified concrete indices should be ignored when unavailable (missing or closed)

allowNoIndices

Boolean — Whether to ignore if a wildcard indices expression resolves into no concrete indices. (This includes _all string or when no indices have been specified)

[expandWildcards=open]

String — Whether to expand wildcard expression to concrete indices that are open, closed or both.

index

String, String[], Boolean — A comma-separated list of index names; use _all or empty string for all indices

body

Object, JSON — An optional request body, as either JSON or a JSON serializable object. See the elasticsearch docs for details about what can be specified here.