Remove TransportDownsampleIndexerAction (#122756)

Author: salvatore-campagna

x-pack/plugin/downsample/src/main/java/org/elasticsearch/xpack/downsample/Downsample.java

@@ -35,7 +35,6 @@
 import org.elasticsearch.threadpool.ThreadPool;
 import org.elasticsearch.xcontent.NamedXContentRegistry;
 import org.elasticsearch.xcontent.ParseField;
-import org.elasticsearch.xpack.core.downsample.DownsampleIndexerAction;
 import org.elasticsearch.xpack.core.downsample.DownsampleShardPersistentTaskState;
 import org.elasticsearch.xpack.core.downsample.DownsampleShardTask;
 
@@ -66,7 +65,6 @@ public List<ExecutorBuilder<?>> getExecutorBuilders(Settings settings) {
     @Override
     public List<ActionHandler<? extends ActionRequest, ? extends ActionResponse>> getActions() {
         return List.of(
-            new ActionHandler<>(DownsampleIndexerAction.INSTANCE, TransportDownsampleIndexerAction.class),
             new ActionHandler<>(DownsampleAction.INSTANCE, TransportDownsampleAction.class),
             new ActionHandler<>(
                 DownsampleShardPersistentTaskExecutor.DelegatingAction.INSTANCE,

x-pack/plugin/downsample/src/main/java/org/elasticsearch/xpack/downsample/DownsampleMetrics.java

@@ -25,8 +25,6 @@
  *  - Add a constant for its name, following the naming conventions for metrics.
  *  - Register it in method {@link #doStart}.
  *  - Add a function for recording its value.
- *  - If needed, inject {@link DownsampleMetrics} to the action containing the logic
- *    that records the metric value. For reference, see {@link TransportDownsampleIndexerAction}.
  */
 public class DownsampleMetrics extends AbstractLifecycleComponent {
 

x-pack/plugin/downsample/src/main/java/org/elasticsearch/xpack/downsample/TransportDownsampleAction.java

@@ -103,7 +103,7 @@
 /**
  * The master downsample action that coordinates
  *  -  creating the downsample index
- *  -  instantiating {@link DownsampleShardIndexer}s to index downsample documents
+ *  -  instantiating {@link org.elasticsearch.persistent.PersistentTasksExecutor} to start a persistent downsample task
  *  -  cleaning up state
  */
 public class TransportDownsampleAction extends AcknowledgedTransportMasterNodeAction<DownsampleAction.Request> {

x-pack/plugin/downsample/src/main/java/org/elasticsearch/xpack/downsample/TransportDownsampleIndexerAction.java

@@ -556,7 +556,6 @@ public class Constants {
         "indices:admin/xpack/ccr/put_follow",
         "indices:admin/xpack/ccr/unfollow",
         "indices:admin/xpack/downsample",
-        "indices:admin/xpack/downsample_indexer",
         "indices:data/read/downsample_delegate",
         "indices:data/read/async_search/delete",
         "indices:data/read/async_search/get",