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[[painless-execute-api]]
=== Painless execute API
experimental[The painless execute api is new and the request / response format may change in a breaking way in the future]
The Painless execute API allows an arbitrary script to be executed and a result to be returned.
[[painless-execute-api-parameters]]
.Parameters
[options="header"]
|======
| Name | Required | Default | Description
| `script` | yes | - | The script to execute
| `context` | no | `painless_test` | The context the script should be executed in.
| `context_setup` | no | - | Additional parameters to the context.
|======
==== Contexts
Contexts control how scripts are executed, what variables are available at runtime and what the return type is.
===== Painless test context
The `painless_test` context executes scripts as is and do not add any special parameters.
The only variable that is available is `params`, which can be used to access user defined values.
The result of the script is always converted to a string.
If no context is specified then this context is used by default.
*Example*
Request:
[source,console]
----------------------------------------------------------------
POST /_scripts/painless/_execute
{
"script": {
"source": "params.count / params.total",
"params": {
"count": 100.0,
"total": 1000.0
}
}
}
----------------------------------------------------------------
Response:
[source,console-result]
--------------------------------------------------
{
"result": "0.1"
}
--------------------------------------------------
===== Filter context
The `filter` context executes scripts as if they were executed inside a `script` query.
For testing purposes a document must be provided that will be indexed temporarily in-memory and
is accessible to the script being tested. Because of this the _source, stored fields and doc values
are available in the script being tested.
The following parameters may be specified in `context_setup` for a filter context:
document:: Contains the document that will be temporarily indexed in-memory and is accessible from the script.
index:: The name of an index containing a mapping that is compatible with the document being indexed.
*Example*
[source,console]
----------------------------------------------------------------
PUT /my-index
{
"mappings": {
"properties": {
"field": {
"type": "keyword"
}
}
}
}
POST /_scripts/painless/_execute
{
"script": {
"source": "doc['field'].value.length() <= params.max_length",
"params": {
"max_length": 4
}
},
"context": "filter",
"context_setup": {
"index": "my-index",
"document": {
"field": "four"
}
}
}
----------------------------------------------------------------
Response:
[source,console-result]
--------------------------------------------------
{
"result": true
}
--------------------------------------------------
===== Score context
The `score` context executes scripts as if they were executed inside a `script_score` function in
`function_score` query.
The following parameters may be specified in `context_setup` for a score context:
document:: Contains the document that will be temporarily indexed in-memory and is accessible from the script.
index:: The name of an index containing a mapping that is compatible with the document being indexed.
query:: If `_score` is used in the script then a query can specified that will be used to compute a score.
*Example*
[source,console]
----------------------------------------------------------------
PUT /my-index
{
"mappings": {
"properties": {
"field": {
"type": "keyword"
},
"rank": {
"type": "long"
}
}
}
}
POST /_scripts/painless/_execute
{
"script": {
"source": "doc['rank'].value / params.max_rank",
"params": {
"max_rank": 5.0
}
},
"context": "score",
"context_setup": {
"index": "my-index",
"document": {
"rank": 4
}
}
}
----------------------------------------------------------------
Response:
[source,console-result]
--------------------------------------------------
{
"result": 0.8
}
--------------------------------------------------