Currently the ranking evaluation API accepts the full query syntax for
the queries specified in the evaluation set and executes them via multi
search. This potentially runs costly aggregations and suggestions too.
This change adds checks that forbid using aggregations, suggesters,
highlighters and the explain and profile options in the queries that are
run as part of the ranking evaluation since they are irrelevent in the
context of this API.
Currently we store the indices specified in the request URL together with all
the other ranking evaluation specification in RankEvalSpec. This is not ideal
since e.g. the indices are not rendered to xContent and so cannot be parsed
back. Instead we should keep them in RankEvalRequest.
Currenty the rest response of the ranking evaluation API wraps all inside an
enclosing `rank_eval` object. This is redundant since it is clear from the API
call and it doesn't provide any other useful information. This change removes
this.
Problem: We introduced the ability to shorten the rank eval request by using a
template in #20231. When playing with the API it turned out that there might be
use cases where - e.g. due to various heuristics - folks might want to translate
the original user query into more than just one type of Elasticsearch query.
Solution: Give each template an id that can later be referenced in the
actual requests.
Closes#21257
Add checks to RankEvalSpec to safe guard against missing parameters.
Fail early in case no metric is supplied, no rated requests are supplied or the search source builder is missing but no template is supplied neither.
Add stricter checks around rank eval request parsing: Fail if in a rated request we see both, a verbatim request as well as request
template parameters.
Relates to #21260
Move rank-eval template compilation down to TransportRankEvalAction
Closes#21777 and #21465
Search templates for rank_eval endpoint so far only worked when sent through
REST end point
However we also allow templates to be set through a Java API call to
"setTemplate" on that same spec. This doesn't go through template execution so
fails further down the line.
To make this work, moved template execution further down, probably to
TransportRankEvalAction.
* Add template IT test for Java API
* Move template compilation to TransportRankEvalAction
This adds support for templating in rank eval requests.
Relates to #20231
Problem: In it's current state the rank-eval request API forces the user to repeat complete queries for each test request. In most use cases the structure of the query to test will be stable with only parameters changing across requests, so this looks like lots of boilerplate json for something that could be expressed in a more concise way.
Uses templating/ ScriptServices to enable users to submit only one test request template and let them only specify template parameters on a per test request basis.
Christoph Büscher
Christoph Büscher
Isabel Drost-Fromm