[Transform] Transform _schedule_now API (#92948)

docs/reference/transform/api-quickref.asciidoc

@@ -18,6 +18,7 @@ _transform/
 * <<reset-transform,Reset {transforms}>>
 * <<start-transform,Start {transforms}>>
 * <<stop-transform,Stop {transforms}>>
+* <<schedule-now-transform,Schedule Now {transforms}>>
 * <<update-transform,Update {transforms}>>
 
 For the full list, see <<transform-apis>>.

docs/reference/transform/apis/index.asciidoc

@@ -15,6 +15,8 @@ include::reset-transform.asciidoc[leveloffset=+2]
 include::start-transform.asciidoc[leveloffset=+2]
 //STOP
 include::stop-transform.asciidoc[leveloffset=+2]
+//SCHEDULE_NOW
+include::schedule-now-transform.asciidoc[leveloffset=+2]
 //UPDATE-UPGRADE
 include::update-transform.asciidoc[leveloffset=+2]
 include::upgrade-transforms.asciidoc[leveloffset=+2]

docs/reference/transform/apis/schedule-now-transform.asciidoc

@@ -0,0 +1,63 @@
+[role="xpack"]
+[testenv="basic"]
+[[schedule-now-transform]]
+= Schedule Now {transform} API
+
+[subs="attributes"]
+++++
+<titleabbrev>Shedule Now {transform}</titleabbrev>
+++++
+
+Schedules now a {transform}.
+
+[[schedule-now-transform-request]]
+== {api-request-title}
+
+`POST _transform/<transform_id>/_schedule_now`
+
+[[schedule-now-transform-prereqs]]
+== {api-prereq-title}
+
+* Requires the `manage_transform` cluster privilege. This privilege is included
+in the `transform_admin` built-in role.
+
+[schedule-now-transform-desc]]
+== {api-description-title}
+
+If you _schedule_now a {transform}, it will process the new data instantly,
+without waiting for the configured `frequency` interval.
+After _schedule_now API is called, the transform will be processed again at
+`now + frequency` unless _schedule_now API is called again in the meantime.
+
+[[schedule-now-transform-path-parms]]
+== {api-path-parms-title}
+
+`<transform_id>`::
+(Required, string)
+include::{es-repo-dir}/rest-api/common-parms.asciidoc[tag=transform-id]
+
+[[schedule-now-transform-query-parms]]
+== {api-query-parms-title}
+
+`timeout`::
+(Optional, time)
+Period to wait for a response. If no response is received before the timeout
+expires, the request fails and returns an error. Defaults to `30s`.
+
+[[schedule-now-transform-examples]]
+== {api-examples-title}
+
+[source,console]
+--------------------------------------------------
+POST _transform/ecommerce_transform/_schedule_now
+--------------------------------------------------
+// TEST[skip:setup kibana sample data]
+
+When the {transform} is scheduled now, you receive the following results:
+
+[source,console-result]
+----
+{
+  "acknowledged" : true
+}
+----

docs/reference/transform/apis/transform-apis.asciidoc

@@ -10,5 +10,6 @@
 * <<reset-transform>>
 * <<start-transform>>
 * <<stop-transform>>
+* <<schedule-now-transform>>
 * <<update-transform>>
 * <<upgrade-transforms>>