This is used when the `top_hits` output is passed to pipeline
aggregators like bucket selectors. The logic retrieves the requested
field from the source of the first SearchHit. This implies that (a) the
spec of the wrapping aggregator (e.g. `bucket_path`) points to an
appropriate field using a bracketed reference (e.g.
`my_top_hits[my_metric]`) and (b) the `top_hits` contains a `size: 1`
setting.
This PR also includes extensions to YAML tests for `top_metrics` and
`top_hits` to cover the cases where these are used in pipeline
aggregations through `bucket_selector`, similar to a HAVING clause in
SQL.
Related to https://github.com/elastic/elasticsearch/issues/73429.
* Soft-deprecation of point/geo_point formats
Since GeoJSON and WKT are now common formats for all three types:
geo_shape, geo_point and point
We decided to soft-deprecate the other point formats by ordering:
* GeoJSON (object with keys `type` and `coordinates`)
* WKT `POINT(x y)`
* Object with keys `lat` and `lon` (or `x` and `y` for point)
* Array [lon,lat]
* String `"lat,lon"` (or `"x,y"` in point)
* String with geohash (only in `geo_point`)
The geohash is last because it is only in one field type.
The string version is second last because it is the most controversial
being the only version to reverse the coordinate order from all other
formats (for geo_point only, since the coordinates are not reversed
in point).
In addition we replaced many examples in both documentation and tests
to prioritize WKT over the plain string format.
Many remaining examples of array format or object with keys still exist
and could be replaced by, for example, GeoJSON, if we feel the need.
* Incorrect quote position
Removes `testenv` annotations and related code. These annotations originally let you skip x-pack snippet tests in the docs. However, that's no longer possible.
Relates to #79309, #31619
Moves the search sort docs from the deprecated 'Request Body Search'
page to a new subpage of 'Run a search'.
No substantive changes were made to the content.
* Removes experimental.
* Replaces `"v"` (for value) with `"m"` (for metric).
* Move the note about tiebreaking into the list of limitations of the
sort.
* Explain how you ask for `metrics`.
* Clean up some wording.
* Link to the docs from `top_metrics`.
Closes#51813
This changes the `top_metrics` aggregation to return metrics in their
original type. Since it only supports numerics, that means that dates,
longs, and doubles will come back as stored, with their appropriate
formatter applied.
The `top_metrics` agg is kind of like `top_hits` but it only works on
doc values so it *should* be faster.
At this point it is fairly limited in that it only supports a single,
numeric sort and a single, numeric metric. And it only fetches the "very
topest" document worth of metric. We plan to support returning a
configurable number of top metrics, requesting more than one metric and
more than one sort. And, eventually, non-numeric sorts and metrics. The
trick is doing those things fairly efficiently.
Co-Authored by: Zachary Tong <zach@elastic.co>
