OpenSearch/docs/reference/ml/anomaly-detection/apis/forecast.asciidoc

[role="xpack"]
[testenv="platinum"]
[[ml-forecast]]
=== Forecast jobs API
++++
<titleabbrev>Forecast jobs</titleabbrev>
++++

Predicts the future behavior of a time series by using its historical behavior. 

[[ml-forecast-request]]
==== {api-request-title}

`POST _ml/anomaly_detectors/<job_id>/_forecast`

[[ml-forecast-prereqs]]
==== {api-prereq-title}

* If the {es} {security-features} are enabled, you must have `manage_ml` or
`manage` cluster privileges to use this API. See
<<security-privileges>>.

[[ml-forecast-desc]]
==== {api-description-title}

See {ml-docs}/ml-overview.html#ml-forecasting[Forecasting the future].

[NOTE]
===============================

* If you use an `over_field_name` property in your job, you cannot create a
forecast. For more information about this property, see <<ml-job-resource>>.
* The job must be open when you create a forecast. Otherwise, an error occurs.
===============================

[[ml-forecast-path-parms]]
==== {api-path-parms-title}

`<job_id>`::
  (Required, string) Identifier for the job.

[[ml-forecast-request-body]]
==== {api-request-body-title}

`duration`::
  (Optional, <<time-units, time units>>) A period of time that indicates how far 
  into the future to forecast. For example, `30d` corresponds to 30 days. The 
  default value is 1 day. The forecast starts at the last record that was 
  processed.

`expires_in`::
  (Optional, <<time-units, time units>>) The period of time that forecast results are retained.
  After a forecast expires, the results are deleted. The default value is 14 days.
  If set to a value of `0`, the forecast is never automatically deleted.

[[ml-forecast-example]]
==== {api-examples-title}

The following example requests a 10 day forecast for the `total-requests` job:

[source,console]
--------------------------------------------------
POST _ml/anomaly_detectors/total-requests/_forecast
{
  "duration": "10d"
}
--------------------------------------------------
// TEST[skip:requires delay]

When the forecast is created, you receive the following results:
[source,js]
----
{
  "acknowledged": true,
  "forecast_id": "wkCWa2IB2lF8nSE_TzZo"
}
----
// NOTCONSOLE

You can subsequently see the forecast in the *Single Metric Viewer* in {kib}.