elasticsearch/docs/reference/scripting-languages/painless/painless-metric-agg-init-context.md

mapped_pages	products
https://www.elastic.co/guide/en/elasticsearch/painless/current/painless-metric-agg-init-context.html	id painless

Metric aggregation initialization context [painless-metric-agg-init-context]

Use a Painless script to initialize values for use in a scripted metric aggregation. An initialization script is run prior to document collection once per shard and is optional as part of the full metric aggregation.

Variables

params (Map, read-only)

User-defined parameters passed in as part of the query.

state (Map)

Empty Map used to add values for use in a map script.

Side Effects

state (Map)

Add values to this Map to for use in a map. Additional values must be of the type Map, List, String or primitive.

Return

void

No expected return value.

API

The standard Painless API is available.