REST hl client: cluster health to default to cluster level

client/rest-high-level/src/test/java/org/elasticsearch/client/ClusterClientIT.java

@@ -129,7 +129,6 @@ public void testClusterHealthYellowClusterLevel() throws IOException {
         createIndex("index2", Settings.EMPTY);
         ClusterHealthRequest request = new ClusterHealthRequest();
         request.timeout("5s");
-        request.level(ClusterHealthRequest.Level.CLUSTER);
         ClusterHealthResponse response = execute(request, highLevelClient().cluster()::health, highLevelClient().cluster()::healthAsync);
 
         assertYellowShards(response);
@@ -170,6 +169,7 @@ public void testClusterHealthYellowSpecificIndex() throws IOException {
         createIndex("index", Settings.EMPTY);
         createIndex("index2", Settings.EMPTY);
         ClusterHealthRequest request = new ClusterHealthRequest("index");
+        request.level(ClusterHealthRequest.Level.SHARDS);
         request.timeout("5s");
         ClusterHealthResponse response = execute(request, highLevelClient().cluster()::health, highLevelClient().cluster()::healthAsync);
 

client/rest-high-level/src/test/java/org/elasticsearch/client/RequestConvertersTests.java

@@ -1568,7 +1568,7 @@ public void testClusterHealth() {
             healthRequest.level(level);
             expectedParams.put("level", level.name().toLowerCase(Locale.ROOT));
         } else {
-            expectedParams.put("level", "shards");
+            expectedParams.put("level", "cluster");
         }
         if (randomBoolean()) {
             Priority priority = randomFrom(Priority.values());

docs/java-rest/high-level/cluster/health.asciidoc

@@ -67,6 +67,7 @@ include-tagged::{doc-tests}/ClusterClientDocumentationIT.java[health-request-wai
 include-tagged::{doc-tests}/ClusterClientDocumentationIT.java[health-request-level]
 --------------------------------------------------
 <1> The level of detail of the returned health information. Accepts a `ClusterHealthRequest.Level` value.
+Default value is `cluster`.
 
 ["source","java",subs="attributes,callouts,macros"]
 --------------------------------------------------

docs/reference/migration/migrate_7_0/restclient.asciidoc

@@ -10,4 +10,11 @@ header, e.g. `client.index(indexRequest)` becomes
 `client.index(indexRequest, RequestOptions.DEFAULT)`.
 In case you are specifying headers
 e.g. `client.index(indexRequest, new Header("name" "value"))` becomes
-`client.index(indexRequest, RequestOptions.DEFAULT.toBuilder().addHeader("name", "value").build());`
+`client.index(indexRequest, RequestOptions.DEFAULT.toBuilder().addHeader("name", "value").build());`
+
+==== Cluster Health API default to `cluster` level
+
+The Cluster Health API used to default to `shards` level to ease migration
+from transport client that doesn't support the `level` parameter and always
+returns information including indices and shards details. The level default
+value has been aligned with the Elasticsearch default level: `cluster`.

server/src/main/java/org/elasticsearch/action/admin/cluster/health/ClusterHealthRequest.java

@@ -48,9 +48,9 @@ public class ClusterHealthRequest extends MasterNodeReadRequest<ClusterHealthReq
     private Priority waitForEvents = null;
     /**
      * Only used by the high-level REST Client. Controls the details level of the health information returned.
-     * The default value is 'shards' so it is backward compatible with the transport client behaviour.
+     * The default value is 'cluster'.
      */
-    private Level level = Level.SHARDS;
+    private Level level = Level.CLUSTER;
 
     public ClusterHealthRequest() {
     }
@@ -250,8 +250,7 @@ public Priority waitForEvents() {
 
     /**
      * Set the level of detail for the health information to be returned.
-     * Only used by the high-level REST Client
-     * The default value is 'shards' so it is backward compatible with the transport client behaviour.
+     * Only used by the high-level REST Client.
      */
     public void level(Level level) {
         this.level = Objects.requireNonNull(level, "level must not be null");
@@ -260,7 +259,6 @@ public void level(Level level) {
     /**
      * Get the level of detail for the health information to be returned.
      * Only used by the high-level REST Client.
-     * The default value is 'shards' so it is backward compatible with the transport client behaviour.
      */
     public Level level() {
         return level;