add missing getter

[mindw]

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[nik9000]

What's the getter for? I think this thing is pretty internal. Does a plugin need it?

[elasticmachine]

Pinging @elastic/es-core-infra (Team:Core/Infra)

[elasticmachine]

Pinging @elastic/es-data-management (Team:Data Management)

[mindw]

@nik9000 yes - the getters are used in the Prometheus exporter plugin https://github.com/vvanholl/elasticsearch-prometheus-exporter. I'm mid-updating with (semi)recent metric changes.

There several more of those I'll try bunching them up.

[nik9000]

Cool. I've unassigned myself here and left it for the experts in stats to have their opinion.

[mindw]

@dakrone any chance you can look at this as well? Tx!

[dakrone]

@elasticmachine update branch

[dakrone]

@elasticmachine ok to test