Add shards_acknowledged and indices results to CloseIndexResponse

Relates: #4001
Relates: elastic/elasticsearch#39687

This commit adds shards_acknowledged and indices resuls to CloseIndexResponse.

src/Nest/Indices/IndexManagement/OpenCloseIndex/CloseIndex/CloseIndexResponse.cs

@@ -1,4 +1,42 @@
-namespace Nest
+using System.Collections.Generic;
+using System.Runtime.Serialization;
+using Elasticsearch.Net;
+
+namespace Nest
 {
-	public class CloseIndexResponse : AcknowledgedResponseBase { }
+	public class CloseIndexResponse : AcknowledgedResponseBase
+	{
+		/// <summary>
+		/// Individual index responses
+		/// <para />
+		/// Valid only for Elasticsearch 7.3.0+
+		/// </summary>
+		[DataMember(Name = "indices")]
+		public IReadOnlyDictionary<string, CloseIndexResult> Indices { get; internal set; } = EmptyReadOnly<string, CloseIndexResult>.Dictionary;
+
+		/// <summary>
+		/// Acknowledgement from shards
+		/// <para />
+		/// Valid only for Elasticsearch 7.2.0+
+		/// </summary>
+		[DataMember(Name = "shards_acknowledged")]
+		public bool ShardsAcknowledged { get; internal set; }
+	}
+
+	[DataContract]
+	public class CloseIndexResult
+	{
+		[DataMember(Name = "closed")]
+		public bool Closed { get; internal set; }
+
+		[DataMember(Name = "shards")]
+		public IReadOnlyDictionary<string, CloseShardResult> Shards { get; internal set; } = EmptyReadOnly<string, CloseShardResult>.Dictionary;
+	}
+
+	[DataContract]
+	public class CloseShardResult
+	{
+		[DataMember(Name = "failures")]
+		public IReadOnlyCollection<ShardFailure> Failures { get; internal set; } = EmptyReadOnly<ShardFailure>.Collection;
+	}
 }

src/Tests/Tests/Indices/IndexManagement/OpenCloseIndex/CloseIndex/CloseIndexApiTests.cs

@@ -1,5 +1,8 @@
-using Elasticsearch.Net;
+using Elastic.Xunit.XunitPlumbing;
+using Elasticsearch.Net;
+using FluentAssertions;
 using Nest;
+using Tests.Core.Extensions;
 using Tests.Core.ManagedElasticsearch.Clusters;
 using Tests.Framework.EndpointTests;
 using Tests.Framework.EndpointTests.TestState;
@@ -25,4 +28,36 @@ protected override LazyResponses ClientUsage() => Calls(
 			(client, r) => client.Indices.CloseAsync(r)
 		);
 	}
+
+	[SkipVersion("<7.3.0", "individual index results only available in 7.3.0+")]
+	public class CloseIndexWithShardsAcknowledgedApiTests
+		: ApiIntegrationAgainstNewIndexTestBase<WritableCluster, CloseIndexResponse, ICloseIndexRequest, CloseIndexDescriptor, CloseIndexRequest>
+	{
+		public CloseIndexWithShardsAcknowledgedApiTests(WritableCluster cluster, EndpointUsage usage) : base(cluster, usage) { }
+
+		protected override bool ExpectIsValid => true;
+		protected override int ExpectStatusCode => 200;
+		protected override HttpMethod HttpMethod => HttpMethod.POST;
+
+		protected override CloseIndexRequest Initializer => new CloseIndexRequest(CallIsolatedValue);
+		protected override string UrlPath => $"/{CallIsolatedValue}/_close";
+
+		protected override LazyResponses ClientUsage() => Calls(
+			(client, f) => client.Indices.Close(CallIsolatedValue),
+			(client, f) => client.Indices.CloseAsync(CallIsolatedValue),
+			(client, r) => client.Indices.Close(r),
+			(client, r) => client.Indices.CloseAsync(r)
+		);
+
+		protected override void ExpectResponse(CloseIndexResponse response)
+		{
+			response.ShouldBeValid();
+			response.ShardsAcknowledged.Should().BeTrue();
+			response.Indices.Should().NotBeNull().And.ContainKey(CallIsolatedValue);
+
+			var closeIndexResult = response.Indices[CallIsolatedValue];
+			closeIndexResult.Closed.Should().BeTrue();
+			closeIndexResult.Shards.Should().NotBeNull();
+		}
+	}
 }