tone max default connections down to 80, add integration tests that proofs connections reuse

added some docs on injecting a custom IConnection

add integration test that proofs connections reuse

Author: Mpdreamz

src/Elasticsearch.Net/Connection/HttpConnection.cs

@@ -76,7 +76,7 @@ protected virtual void AlterServicePoint(ServicePoint requestServicePoint, Reque
 		{
 			requestServicePoint.UseNagleAlgorithm = false;
 			requestServicePoint.Expect100Continue = false;
-			requestServicePoint.ConnectionLimit = 10000;
+			requestServicePoint.ConnectionLimit = 80;
 			//looking at http://referencesource.microsoft.com/#System/net/System/Net/ServicePoint.cs
 			//this method only sets internal values and wont actually cause timers and such to be reset
 			//So it should be idempotent if called with the same parameters

src/Elasticsearch.Net/Connection/InMemoryConnection.cs

@@ -12,6 +12,10 @@ public class InMemoryConnection : IConnection
 		private readonly int _statusCode;
 		private readonly Exception _exception;
 
+		/// <summary>
+		/// Every request will succeed with this overload, note that it won't actually return mocked responses
+		/// so using this overload might fail if you are using it to test high level bits that need to deserialize the response.
+		/// </summary>
 		public InMemoryConnection()
 		{
 			_statusCode = 200;

src/Tests/ClientConcepts/Connection/CustomConnections.cs

@@ -0,0 +1,69 @@
+using Elasticsearch.Net;
+using FluentAssertions;
+using Nest;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using Tests.Framework;
+using System.Net;
+
+namespace Tests.ClientConcepts.Connection
+{
+	public class CustomConnections
+	{
+		/**== Custom Connection Implementations
+		*
+		* The client abstracts sending the request and creating a response behind `IConnection`
+		*
+		* By default the client will use a WebRequest based version on the desktop CLR (.NET 4.5 and up targets)
+		* and a HttpClient based HttpConnection specifically build for the Core CLR (netstandard 1.6).
+		*
+		* The reason for the split is because WebRequest and ServicePoint are not directly available on netstandard 1.6
+		*
+		* However the implementation written against WebRequest is the most matured implementation that we weren't ready to it give up.
+		* There are also a couple of important toggles that are easy to set against a `ServicePoint` that we'd have to give up
+		* had we jumped on the `HttpClient` completely.
+		*
+		* Another limitation is that `HttpClient` has no synchronous code paths and supporting that means doing hacky async patches which definitely
+		* need time to bake.
+		*
+		* So why would you ever want to pass your own `IConnection`? Let's look at a couple of examples
+		*
+		*/
+
+		public void OverrideHow()
+		{
+			var connection = new InMemoryConnection();
+			var connectionPool = new SingleNodeConnectionPool(new Uri("http://localhost:9200"));
+			var settings = new ConnectionSettings(connectionPool, connection);
+			var client = new ElasticClient(settings);
+		}
+
+		/**
+		 * Here we create a new `ConnectionSettings` by using the overload that takes a `IConnectionPool` and an `IConnection`.
+		 * We pass it an `InMemoryConnection` which using this constructor will return 200 for everything and never actually perform any IO.
+		 *
+		 * `InMemoryConnection` is great to write unit tests with as there is another overload that takes a fixed response stream to return.
+		 *
+		 *
+		 * === ServicePoint hacking
+		 *
+		 * If you are running on the desktop CLR you can override specific properties for the current `ServicePoint` easily by overriding
+		 * `AlterServicePoint` e.g to change the default connection limit to a specific endpoint from 80 to something higher.
+		 * Remember though that we reuse TCP connections so changing this to something really high should only be done with careful consideration.
+		 */
+
+		public class MySpecialHttpConnection : HttpConnection
+		{
+			protected override void AlterServicePoint(ServicePoint requestServicePoint, RequestData requestData)
+			{
+				base.AlterServicePoint(requestServicePoint, requestData);
+				requestServicePoint.ConnectionLimit = 10000;
+				requestServicePoint.UseNagleAlgorithm = true;
+			}
+
+		}
+	}
+}

src/Tests/Reproduce/ConnectionReuseAndBalancing.cs

@@ -0,0 +1,73 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using Tests.Framework;
+using Tests.Framework.Integration;
+using Tests.Framework.MockData;
+using Xunit;
+
+using Elasticsearch.Net;
+using Nest;
+using FluentAssertions;
+using System.Threading;
+using System.Reactive.Linq;
+using static Nest.Infer;
+
+namespace Tests.Reproduce
+{
+	public class ConnectionReuseCluster : ClusterBase { }
+	public class ConnectionReuseAndBalancing : IClusterFixture<ConnectionReuseCluster>
+	{
+		private readonly ConnectionReuseCluster _cluster;
+
+		public ConnectionReuseAndBalancing(ConnectionReuseCluster cluster)
+		{
+			_cluster = cluster;
+		}
+
+		public IEnumerable<Project> MockDataGenerator(int numDocuments)
+		{
+			foreach (var i in Enumerable.Range(0, numDocuments))
+				yield return new Project { Name = $"project-{i}" };
+		}
+
+		[I] public async Task IndexAndSearchABunch()
+		{
+			var tokenSource = new CancellationTokenSource();
+			var client = _cluster.Client;
+
+			await client.DeleteIndexAsync(Index<Project>());
+			var observableBulk = client.BulkAll(this.MockDataGenerator(100000), f => f
+				.MaxDegreeOfParallelism(10)
+				.BackOffTime(TimeSpan.FromSeconds(10))
+				.BackOffRetries(2)
+				.Size(1000)
+				.RefreshOnCompleted()
+			, tokenSource.Token);
+			await observableBulk.ForEachAsync(x => { }, tokenSource.Token);
+			var statsRequest = new NodesStatsRequest(NodesStatsMetric.Http);
+			var nodeStats = await client.NodesStatsAsync(statsRequest);
+			this.AssertHttpStats(nodeStats);
+			for (var i = 0; i < 10; i++)
+			{
+				Parallel.For(0, 1000, async (c) => await client.SearchAsync<Project>(s => s));
+
+				nodeStats = await client.NodesStatsAsync(statsRequest);
+				this.AssertHttpStats(nodeStats);
+			}
+		}
+
+		private void AssertHttpStats(INodesStatsResponse response)
+		{
+			foreach(var node in response.Nodes.Values)
+			{
+				node.Http.TotalOpened.Should().BeGreaterThan(2);
+				node.Http.TotalOpened.Should().BeLessThan(100);
+				node.Http.CurrentOpen.Should().BeLessThan(100);
+			}
+
+		}
+	}
+}

src/Tests/Tests.csproj

@@ -220,6 +220,7 @@
     <Compile Include="Cat\CatThreadPool\CatThreadPoolUrlTests.cs" />
     <Compile Include="ClientConcepts\ConnectionPooling\Dispose\ResponseBuilderDisposeTests.cs" />
     <Compile Include="ClientConcepts\ConnectionPooling\Sniffing\AddressParsing.doc.cs" />
+    <Compile Include="ClientConcepts\Connection\CustomConnections.cs" />
     <Compile Include="Cluster\TaskManagement\GetTask\GetTaskApiTests.cs" />
     <Compile Include="Cluster\TaskManagement\GetTask\GetTaskUrlTests.cs" />
     <Compile Include="CodeStandards\Responses.doc.cs" />
@@ -238,9 +239,11 @@
     <Compile Include="Framework\EndpointTests\TestState\AsyncLazy.cs" />
     <Compile Include="Framework\EndpointTests\Clusters\IntrusiveOperationCluster.cs" />
     <Compile Include="Framework\EndpointTests\Clusters\WritableCluster.cs" />
+    <Compile Include="Framework\EndpointTests\TestState\ClientMethod.cs" />
     <Compile Include="Framework\Extensions\ReadOnlyDictionaryAssertions.cs" />
     <Compile Include="Framework\Extensions\ShouldExtensions.cs" />
     <Compile Include="Framework\ManagedElasticsearch\FileSystem\INodeFileSystem.cs" />
+    <Compile Include="Framework\ManagedElasticsearch\Process\ElasticsearchConsoleOut.cs" />
     <Compile Include="Framework\MockData\GeoIp.cs" />
     <Compile Include="Framework\SerializationTests\DictionarySerializationTests.cs" />
     <Compile Include="Framework\VirtualClustering\Audit\Auditor.cs" />
@@ -493,6 +496,7 @@
     <Compile Include=".\QueryDsl\Geo\Shape\MultiPoint\GeoMultiPointUsageTests.cs" />
     <Compile Include=".\QueryDsl\Geo\Shape\Point\GeoPointUsageTests.cs" />
     <Compile Include=".\QueryDsl\Geo\Shape\Polygon\GeoPolygonUsageTests.cs" />
+    <Compile Include="QueryDsl\ConditionlessWhen.cs" />
     <Compile Include="QueryDsl\Geo\Shape\GeoShapeQueryUsageTestsBase.cs" />
     <Compile Include=".\QueryDsl\Joining\HasChild\HasChildQueryUsageTests.cs" />
     <Compile Include=".\QueryDsl\Joining\HasParent\HasParentQueryUsageTests.cs" />
@@ -615,13 +619,11 @@
     <Compile Include="Document\Multiple\UpdateByQuery\UpdateByQueryApiTests.cs" />
     <Compile Include="Document\Multiple\UpdateByQuery\UpdateByQueryUrlTests.cs" />
     <Compile Include="Framework\EndpointTests\TestState\CallUniqueValues.cs" />
-    <Compile Include="Framework\EndpointTests\TestState\ClientMethod.cs" />
-    <Compile Include="Framework\ManagedElasticsearch\Process\ElasticsearchConsoleOut.cs" />
-    <Compile Include="QueryDsl\ConditionlessWhen.cs" />
     <Compile Include="QueryDsl\Joining\ParentId\ParentIdUsageTests.cs" />
     <Compile Include="QueryDsl\MatchNoneQueryUsageTests.cs" />
     <Compile Include="QueryDsl\NotConditionlessWhen.cs" />
     <Compile Include="QueryDsl\Specialized\Percolate\PercolateQueryUsageTests.cs" />
+    <Compile Include="Reproduce\ConnectionReuseAndBalancing.cs" />
     <Compile Include="Reproduce\DateSerialization.cs" />
     <Compile Include="Reproduce\GithubIssue2152.cs" />
     <Compile Include="Reproduce\GithubIssue2306.cs" />
@@ -753,9 +755,7 @@
     <Content Include="ClientConcepts\LowLevel\pipeline.xml" />
     <Content Include="QueryDsl\BoolDsl\hadouken-indentation.jpg" />
   </ItemGroup>
-  <ItemGroup>
-    <Folder Include="ClientConcepts\Connection\" />
-  </ItemGroup>
+  <ItemGroup />
   <Import Project="..\outputpath.props" />
   <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
   <Choose>