Expose seting for "lookback" range for _field_stats API

[pjcard]

The issue 'Missing mappings' #3226 describes issues I too encountered when attempting to update my mappings. My problem was the same, that I was unaware that time based indicies limited the number of previous days in which they searched for new fields.

Now that I'm aware of it, this setting makes perfect sense, but it is hidden in the advanced page, underneath a warning about not changing it. I think perhaps it would be beneficial to either allow viewing or viewing and altering of the value at the point at which 'Reload field list is accessed'.

[w33ble]

Dealing with time based indices in Kibana will be going away with #4342. Since it's all getting removed, we're not planning to enhance what we have now too much. I'm going to close this since there is already a workaround for it as you pointed out.

[pjcard]

Great news about the related enhancement, that actually solves another issue I've been having (how to efficiently target a range of date based indices).

But won't the reload mappings still require a lookback value? Even if it's using the _field_stats api instead of an index pattern, won't it still need to know how far back to look for new mappings?

[w33ble]

That's a good point, the API will still need to be told how far back to look, and it would be nice if the user can specify that range. Since I don't see any specific mention of that in the _field_stats issue, I'm re-opening and linking that issue back here.

[pjcard]

Thanks, much appreciated.

[jbudz]

We removed usage of the field stats API, closed by #12814