Return default when no bytes read from response streaming-no-response… (

#3882)

* Return default when no bytes read from response streaming-no-response-body

This commit returns default(T) when no bytes are read from the response stream.
Move the stream null and seek check into JsonSerializer.

Update index exists integration test to not disable direct streaming in order to test.

* Changed formatting to indented

* do not disable direct streaming

src/Elasticsearch.Net/Serialization/LowLevelRequestResponseSerializer.cs

@@ -13,29 +13,21 @@ public class LowLevelRequestResponseSerializer : IElasticsearchSerializer
 
 		public object Deserialize(Type type, Stream stream)
 		{
-			if (stream == null || stream.CanSeek && stream.Length == 0) return Task.FromResult(type.DefaultValue());
-
 			return JsonSerializer.NonGeneric.Deserialize(type, stream, ElasticsearchNetFormatterResolver.Instance);
 		}
 
 		public T Deserialize<T>(Stream stream)
 		{
-			if (stream == null || stream.CanSeek && stream.Length == 0) return default(T);
-
 			return JsonSerializer.Deserialize<T>(stream, ElasticsearchNetFormatterResolver.Instance);
 		}
 
 		public Task<object> DeserializeAsync(Type type, Stream stream, CancellationToken cancellationToken = default)
 		{
-			if (stream == null || stream.CanSeek && stream.Length == 0) return Task.FromResult(type.DefaultValue());
-
 			return JsonSerializer.NonGeneric.DeserializeAsync(type, stream, ElasticsearchNetFormatterResolver.Instance);
 		}
 
 		public Task<T> DeserializeAsync<T>(Stream stream, CancellationToken cancellationToken = default)
 		{
-			if (stream == null || stream.CanSeek && stream.Length == 0) return Task.FromResult(default(T));
-
 			return JsonSerializer.DeserializeAsync<T>(stream, ElasticsearchNetFormatterResolver.Instance);
 		}
 

src/Elasticsearch.Net/Utf8Json/JsonSerializer.cs

@@ -26,6 +26,7 @@
 using System.IO;
 using System.Linq;
 using System.Text;
+using System.Threading.Tasks;
 using Elasticsearch.Net.Utf8Json.Internal;
 using Elasticsearch.Net.Utf8Json.Resolvers;
 
@@ -254,7 +255,11 @@ public static T Deserialize<T>(byte[] bytes, int offset)
 
         public static T Deserialize<T>(byte[] bytes, int offset, IJsonFormatterResolver resolver)
         {
-            if (resolver == null) resolver = DefaultResolver;
+			if (bytes == null || bytes.Length == 0)
+				return default;
+
+            if (resolver == null)
+				resolver = DefaultResolver;
 
             var reader = new JsonReader(bytes, offset);
             var formatter = resolver.GetFormatterWithVerify<T>();
@@ -281,11 +286,14 @@ public static T Deserialize<T>(Stream stream)
 
         public static T Deserialize<T>(Stream stream, IJsonFormatterResolver resolver)
         {
-            if (resolver == null) resolver = DefaultResolver;
+			if (stream == null || stream.CanSeek && stream.Length == 0)
+				return default;
+
+            if (resolver == null)
+				resolver = DefaultResolver;
 
 #if NETSTANDARD && !NET45
-            var ms = stream as MemoryStream;
-            if (ms != null)
+			if (stream is MemoryStream ms)
             {
 				if (ms.TryGetBuffer(out var buf2))
                 {
@@ -302,39 +310,63 @@ public static T Deserialize<T>(Stream stream, IJsonFormatterResolver resolver)
                 }
             }
 #endif
-            {
-				var buf = MemoryPool.Rent();
-				var poolBuf = buf;
-				try
-				{
-					var len = FillFromStream(stream, ref buf);
+            var buf = MemoryPool.Rent();
+			var poolBuf = buf;
+			try
+			{
+				var length = FillFromStream(stream, ref buf);
 
-					// when token is number, can not use from pool(can not find end line).
-					var token = new JsonReader(buf).GetCurrentJsonToken();
-					if (token == JsonToken.Number)
-					{
-						buf = BinaryUtil.FastCloneWithResize(buf, len);
-					}
+				if (length == 0)
+					return default;
 
-					return Deserialize<T>(buf, resolver);
-				}
-				finally
+				// when token is number, can not use from pool(can not find end line).
+				var token = new JsonReader(buf).GetCurrentJsonToken();
+				if (token == JsonToken.Number)
 				{
-					MemoryPool.Return(poolBuf);
+					buf = BinaryUtil.FastCloneWithResize(buf, length);
 				}
-            }
+
+				return Deserialize<T>(buf, resolver);
+			}
+			finally
+			{
+				MemoryPool.Return(poolBuf);
+			}
         }
 
 #if NETSTANDARD
 
-        public static System.Threading.Tasks.Task<T> DeserializeAsync<T>(Stream stream)
+        public static Task<T> DeserializeAsync<T>(Stream stream)
         {
             return DeserializeAsync<T>(stream, defaultResolver);
         }
 
-        public static async System.Threading.Tasks.Task<T> DeserializeAsync<T>(Stream stream, IJsonFormatterResolver resolver)
+        public static async Task<T> DeserializeAsync<T>(Stream stream, IJsonFormatterResolver resolver)
         {
-            if (resolver == null) resolver = DefaultResolver;
+			if (stream == null || stream.CanSeek && stream.Length == 0)
+				return default;
+
+            if (resolver == null)
+				resolver = DefaultResolver;
+
+#if NETSTANDARD && !NET45
+			if (stream is MemoryStream ms)
+            {
+				if (ms.TryGetBuffer(out var buf2))
+                {
+                    // when token is number, can not use from pool(can not find end line).
+                    var token = new JsonReader(buf2.Array, buf2.Offset).GetCurrentJsonToken();
+                    if (token == JsonToken.Number)
+                    {
+                        var buf3 = new byte[buf2.Count];
+                        Buffer.BlockCopy(buf2.Array, buf2.Offset, buf3, 0, buf3.Length);
+                        return Deserialize<T>(buf3, 0, resolver);
+                    }
+
+                    return Deserialize<T>(buf2.Array, buf2.Offset, resolver);
+                }
+            }
+#endif
 
             var buffer = MemoryPool.Rent();
             var buf = buffer;
@@ -346,11 +378,12 @@ public static async System.Threading.Tasks.Task<T> DeserializeAsync<T>(Stream st
                 {
                     length += read;
                     if (length == buf.Length)
-                    {
-                        BinaryUtil.FastResize(ref buf, length * 2);
-                    }
+						BinaryUtil.FastResize(ref buf, length * 2);
                 }
 
+				if (length == 0)
+					return default;
+
                 // when token is number, can not use from pool(can not find end line).
                 var token = new JsonReader(buf).GetCurrentJsonToken();
                 if (token == JsonToken.Number)

src/Nest/CommonAbstractions/Extensions/TypeExtensions.cs

@@ -69,17 +69,6 @@ internal static object CreateInstance(this Type t, params object[] args)
 			return activator(args);
 		}
 
-		internal static object DefaultValue(this Type type) =>
-			type.IsValueType
-				? CachedDefaultValues.GetOrAdd(type, t =>
-						Expression.Lambda<Func<object>>(
-								Expression.Convert(Expression.Default(type), typeof(object))
-							)
-							.Compile()
-					)
-					.Invoke()
-				: null;
-
 		//do not remove this is referenced through GetActivatorMethod
 		internal static ObjectActivator<T> GetActivator<T>(ConstructorInfo ctor)
 		{

src/Nest/CommonAbstractions/SerializationBehavior/DefaultHighLevelSerializer.cs

@@ -16,36 +16,28 @@ internal class DefaultHighLevelSerializer : IElasticsearchSerializer, IInternalS
 
 		public T Deserialize<T>(Stream stream)
 		{
-			if (stream == null || stream.CanSeek && stream.Length == 0) return default;
-
 			return JsonSerializer.Deserialize<T>(stream, FormatterResolver);
 		}
 
 		public object Deserialize(Type type, Stream stream)
 		{
-			if (stream == null || stream.CanSeek && stream.Length == 0) return type.DefaultValue();
-
 			return JsonSerializer.NonGeneric.Deserialize(type, stream, FormatterResolver);
 		}
 
 		public Task<T> DeserializeAsync<T>(Stream stream, CancellationToken cancellationToken = default)
 		{
-			if (stream == null || stream.CanSeek && stream.Length == 0) return Task.FromResult(default(T));
-
 			return JsonSerializer.DeserializeAsync<T>(stream, FormatterResolver);
 		}
 
 		public Task<object> DeserializeAsync(Type type, Stream stream, CancellationToken cancellationToken = default)
 		{
-			if (stream == null || stream.CanSeek && stream.Length == 0) return Task.FromResult(type.DefaultValue());
-
 			return JsonSerializer.NonGeneric.DeserializeAsync(type, stream, FormatterResolver);
 		}
 
-		public virtual void Serialize<T>(T data, Stream writableStream, SerializationFormatting formatting = SerializationFormatting.Indented) =>
+		public virtual void Serialize<T>(T data, Stream writableStream, SerializationFormatting formatting = SerializationFormatting.None) =>
 			JsonSerializer.Serialize(writableStream, data, FormatterResolver);
 
-		public Task SerializeAsync<T>(T data, Stream stream, SerializationFormatting formatting = SerializationFormatting.Indented,
+		public Task SerializeAsync<T>(T data, Stream stream, SerializationFormatting formatting = SerializationFormatting.None,
 			CancellationToken cancellationToken = default
 		) => JsonSerializer.SerializeAsync(stream, data, FormatterResolver);
 	}

src/Tests/Tests.Core/ManagedElasticsearch/Clusters/ClientTestClusterBase.cs

@@ -13,11 +13,11 @@ namespace Tests.Core.ManagedElasticsearch.Clusters
 {
 	public abstract class ClientTestClusterBase : XunitClusterBase<ClientTestClusterConfiguration>, INestTestCluster
 	{
-		public ClientTestClusterBase() : this(new ClientTestClusterConfiguration()) { }
+		protected ClientTestClusterBase() : this(new ClientTestClusterConfiguration()) { }
 
-		public ClientTestClusterBase(params ElasticsearchPlugin[] plugins) : this(new ClientTestClusterConfiguration(plugins)) { }
+		protected ClientTestClusterBase(params ElasticsearchPlugin[] plugins) : this(new ClientTestClusterConfiguration(plugins)) { }
 
-		public ClientTestClusterBase(ClientTestClusterConfiguration configuration) : base(configuration) { }
+		protected ClientTestClusterBase(ClientTestClusterConfiguration configuration) : base(configuration) { }
 
 		public IElasticClient Client => this.GetOrAddClient(s => ConnectionSettings(s.ApplyDomainSettings()));
 

src/Tests/Tests/Indices/IndexManagement/IndicesExists/IndexExistsApiTests.cs

@@ -1,6 +1,7 @@
 using Elasticsearch.Net;
 using FluentAssertions;
 using Nest;
+using Tests.Core.Client.Settings;
 using Tests.Core.ManagedElasticsearch.Clusters;
 using Tests.Domain;
 using Tests.Framework.EndpointTests;
@@ -31,6 +32,7 @@ protected override LazyResponses ClientUsage() => Calls(
 		protected override void ExpectResponse(ExistsResponse response) => response.Exists.Should().BeTrue();
 	}
 
+	// DisableDirectStreaming = false so that response stream is not seekable
 	public class IndexNotExistsApiTests
 		: ApiIntegrationTestBase<ReadOnlyCluster, ExistsResponse, IIndexExistsRequest, IndexExistsDescriptor, IndexExistsRequest>
 	{
@@ -42,12 +44,18 @@ public IndexNotExistsApiTests(ReadOnlyCluster cluster, EndpointUsage usage) : ba
 		protected override int ExpectStatusCode => 404;
 		protected override HttpMethod HttpMethod => HttpMethod.HEAD;
 
-		protected override IndexExistsRequest Initializer => new IndexExistsRequest(NonExistentIndex);
+		protected override IndexExistsRequest Initializer => new IndexExistsRequest(NonExistentIndex)
+		{
+			RequestConfiguration = new RequestConfiguration
+			{
+				DisableDirectStreaming = false
+			}
+		};
 		protected override string UrlPath => $"/{NonExistentIndex}";
 
 		protected override LazyResponses ClientUsage() => Calls(
-			(client, f) => client.Indices.Exists(NonExistentIndex),
-			(client, f) => client.Indices.ExistsAsync(NonExistentIndex),
+			(client, f) => client.Indices.Exists(NonExistentIndex, r => r.RequestConfiguration(c => c.DisableDirectStreaming(false))),
+			(client, f) => client.Indices.ExistsAsync(NonExistentIndex,r => r.RequestConfiguration(c => c.DisableDirectStreaming(false))),
 			(client, r) => client.Indices.Exists(r),
 			(client, r) => client.Indices.ExistsAsync(r)
 		);