82 lines
2.4 KiB
Plaintext
82 lines
2.4 KiB
Plaintext
|
|
[[painless-bucket-selector-agg-context]]
|
|
=== Bucket selector aggregation context
|
|
|
|
Use a Painless script in an
|
|
{ref}/search-aggregations-pipeline-bucket-selector-aggregation.html[`bucket_selector` aggregation]
|
|
to determine if a bucket should be retained or filtered out.
|
|
|
|
==== Variables
|
|
|
|
`params` (`Map`, read-only)::
|
|
User-defined parameters passed in as part of the query. The parameters
|
|
include values defined as part of the `buckets_path`.
|
|
|
|
==== Return
|
|
|
|
boolean::
|
|
True if the bucket should be retained, false if the bucket should be filtered out.
|
|
|
|
==== API
|
|
|
|
|
|
To run this example, first follow the steps in <<painless-context-examples, context examples>>.
|
|
|
|
The painless context in a `bucket_selector` aggregation provides a `params` map. This map contains both
|
|
user-specified custom values, as well as the values from other aggregations specified in the `buckets_path`
|
|
property.
|
|
|
|
Unlike some other aggregation contexts, the `bucket_selector` context must return a boolean `true` or `false`.
|
|
|
|
This example finds the max of each bucket, adds a user-specified base_cost, and retains all of the
|
|
buckets that are greater than `10`.
|
|
|
|
[source,Painless]
|
|
--------------------------------------------------
|
|
params.max + params.base_cost > 10
|
|
--------------------------------------------------
|
|
|
|
Note that the values are extracted from the `params` map. The script is in the form of an expression
|
|
that returns `true` or `false`. In context, the aggregation looks like this:
|
|
|
|
[source,js]
|
|
--------------------------------------------------
|
|
GET /seats/_search
|
|
{
|
|
"size": 0,
|
|
"aggs": {
|
|
"theatres": {
|
|
"terms": {
|
|
"field": "theatre",
|
|
"size": 10
|
|
},
|
|
"aggs": {
|
|
"max_cost": {
|
|
"max": {
|
|
"field": "cost"
|
|
}
|
|
},
|
|
"filtering_agg": {
|
|
"bucket_selector": {
|
|
"buckets_path": { <1>
|
|
"max": "max_cost"
|
|
},
|
|
"script": {
|
|
"params": {
|
|
"base_cost": 5 <2>
|
|
},
|
|
"source": "params.max + params.base_cost > 10"
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
--------------------------------------------------
|
|
// CONSOLE
|
|
// TEST[setup:seats]
|
|
<1> The `buckets_path` points to the max aggregations (`max_cost`) and adds `max` variables
|
|
to the `params` map
|
|
<2> The user-specified `base_cost` is also added to the `params` map
|