Remove node info from ML team serverless responses (#2205)

Serverless will present the impression of having no underlying servers,
so API responses in serverless should not contain any node information.

To avoid changing the shape of responses, we still return node fields
but always set to "serverless" in serverless. This avoids causing
problems for users who want to use the stateful client with serverless.

Trained model stats will be aggregated and reported as being for a
virtual node called "serverless".

Author: droberts195

output/schema/schema.json

@@ -140,6 +140,9 @@ export enum DatafeedState {
 export class DatafeedStats {
   assignment_explanation?: string
   datafeed_id: Id
+  /**
+   * @availability stack
+   */
   node?: DiscoveryNode
   state: DatafeedState
   timing_stats: DatafeedTimingStats

specification/ml/_types/Datafeed.ts

@@ -332,7 +332,10 @@ export class DataframeAnalytics {
   id: Id
   /** An object describing memory usage of the analytics. It is present only after the job is started and memory usage is reported. */
   memory_usage: DataframeAnalyticsStatsMemoryUsage
-  /** Contains properties for the node that runs the job. This information is available only for running jobs. */
+  /**
+   * Contains properties for the node that runs the job. This information is available only for running jobs.
+   * @availability stack
+   */
   node?: NodeAttributes
   /** The progress report of the data frame analytics job by phase. */
   progress: DataframeAnalyticsStatsProgress[]

specification/ml/_types/DataframeAnalytics.ts

@@ -109,6 +109,9 @@ export class JobStats {
   forecasts_stats: JobForecastStatistics
   job_id: string
   model_size_stats: ModelSizeStats
+  /**
+   * @availability stack
+   */
   node?: DiscoveryNode
   open_time?: DateTime
   state: JobState

specification/ml/_types/Job.ts

@@ -49,6 +49,9 @@ export class ModelSnapshotUpgrade {
   job_id: Id
   snapshot_id: Id
   state: SnapshotUpgradeState
+  /**
+   * @availability stack
+   */
   node: DiscoveryNode
   assignment_explanation: string
 }

specification/ml/_types/Model.ts

@@ -71,7 +71,10 @@ export class TrainedModelDeploymentStats {
   inference_count: integer
   /** The unique identifier for the trained model. */
   model_id: Id
-  /** The deployent stats for each node that currently has the model allocated. */
+  /**
+   * The deployment stats for each node that currently has the model allocated.
+   * In serverless, stats are reported for a single unnamed virtual node.
+   */
   nodes: TrainedModelDeploymentNodesStats
   /** The number of allocations requested. */
   number_of_allocations: integer
@@ -136,7 +139,10 @@ export class TrainedModelDeploymentNodesStats {
   inference_count: integer
   /** The epoch time stamp of the last inference call for the model on this node. */
   last_access: long
-  /** Information pertaining to the node. */
+  /**
+   * Information pertaining to the node.
+   * @availability stack
+   */
   node: DiscoveryNode
   /**
    * The number of allocations assigned to this node.

specification/ml/_types/TrainedModel.ts

@@ -22,6 +22,10 @@ import { NodeId } from '@_types/common'
 export class Response {
   body: {
     opened: boolean
+    /**
+     * The ID of the node that the job was started on. In serverless this will be the "serverless".
+     * If the job is allowed to open lazily and has not yet been assigned to a node, this value is an empty string.
+     */
     node: NodeId
   }
 }

specification/ml/open_job/MlOpenJobResponse.ts

@@ -22,7 +22,13 @@ import { NodeId } from '@_types/common'
 export class Response {
   body: {
     acknowledged: boolean
-    /** The ID of the node that the job was started on. If the job is allowed to open lazily and has not yet been assigned to a node, this value is an empty string. */
+    /**
+     * The ID of the node that the job was started on. If the job is allowed to open lazily and has not yet been assigned to a node, this value is an empty string.
+     * The node ID of the node the job has been assigned to, or
+     * an empty string if it hasn't been assigned to a node. In
+     * serverless if the job has been assigned to run then the
+     * node ID will be "serverless".
+     */
     node: NodeId
   }
 }

specification/ml/start_data_frame_analytics/MlStartDataFrameAnalyticsResponse.ts

@@ -22,8 +22,8 @@ import { NodeIds } from '@_types/common'
 export class Response {
   body: {
     /**
-     * The ID of the node that the datafeed was started on. If the datafeed is allowed to open lazily and has not yet
-     * been assigned to a node, this value is an empty string.
+     * The ID of the node that the job was started on. In serverless this will be the "serverless".
+     * If the job is allowed to open lazily and has not yet been assigned to a node, this value is an empty string.
      */
     node: NodeIds
     /**

specification/ml/start_datafeed/MlStartDatafeedResponse.ts

@@ -21,7 +21,9 @@ import { NodeId } from '@_types/common'
 
 export class Response {
   body: {
-    /** The ID of the assigned node for the upgrade task if it is still running. */
+    /**
+     * The ID of the node that the upgrade task was started on if it is still running. In serverless this will be the "serverless".
+     */
     node: NodeId
     /** When true, this means the task is complete. When false, it is still running. */
     completed: boolean

specification/ml/upgrade_job_snapshot/MlUpgradeJobSnapshotResponse.ts

@@ -32,6 +32,9 @@ export class TransformStats {
   checkpointing: Checkpointing
   health?: TransformStatsHealth
   id: Id
+  /**
+   * @availability stack
+   */
   node?: NodeAttributes
   reason?: string
   state: string