Set HttpClientHandler.UseProxy=false on DisableAutomaticProxyDetection==true (#2911)

Author: codeh

src/Elasticsearch.Net/Connection/HttpConnection-CoreFx.cs

@@ -186,9 +186,10 @@ protected virtual HttpClientHandler CreateHttpClientHandler(RequestData requestD
 				}
 				handler.Proxy = proxy;
 			}
-
-			if (requestData.DisableAutomaticProxyDetection)
-				handler.Proxy = null;
+			else if (requestData.DisableAutomaticProxyDetection)
+			{
+				handler.UseProxy = false;
+			}
 
 			var callback = requestData?.ConnectionSettings?.ServerCertificateValidationCallback;
 			if (callback != null && handler.ServerCertificateCustomValidationCallback == null)

src/Tests/ClientConcepts/Connection/HttpConnectionTests.cs

@@ -2,12 +2,14 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using System.Net.Http;
 using System.Threading;
 using System.Threading.Tasks;
 using Elasticsearch.Net;
 using FluentAssertions;
 using Nest;
 using Tests.Framework;
+using HttpMethod = Elasticsearch.Net.HttpMethod;
 
 namespace Tests.ClientConcepts.Connection
 {
@@ -19,6 +21,8 @@ public class TestableHttpConnection : HttpConnection
 
 		    public int CallCount { get; private set; }
 
+		    public HttpClientHandler LastUsedHttpClientHandler { get; private set; }
+
 		    public override ElasticsearchResponse<TReturn> Request<TReturn>(RequestData requestData)
 		    {
 			    CallCount++;
@@ -30,6 +34,12 @@ public override Task<ElasticsearchResponse<TReturn>> RequestAsync<TReturn>(Reque
 			    CallCount++;
 			    return base.RequestAsync<TReturn>(requestData, cancellationToken);
 		    }
+
+		    protected override HttpClientHandler CreateHttpClientHandler(RequestData requestData)
+		    {
+			    LastUsedHttpClientHandler = base.CreateHttpClientHandler(requestData);
+			    return LastUsedHttpClientHandler;
+		    }
 	    }
 
 	    [U]
@@ -112,6 +122,36 @@ private static RequestData CreateRequestData(
 		    };
 		    return requestData;
 	    }
+
+	    /// <summary>
+	    /// Setting HttpClientHandler.Proxy = null don't disable HttpClient automatic proxy detection.
+	    /// It is disabled by setting Proxy to non-null value or by setting UseProxy = false.
+	    /// </summary>
+	    [U]
+	    public async Task HttpClientUseProxyShouldBeFalseWhenDisabledAutoProxyDetection()
+	    {
+		    var connection = new TestableHttpConnection();
+		    var requestData = CreateRequestData(disableAutomaticProxyDetection: true);
+
+		    connection.Request<string>(requestData);
+		    connection.LastUsedHttpClientHandler.UseProxy.Should().BeFalse();
+
+		    await connection.RequestAsync<string>(requestData, CancellationToken.None).ConfigureAwait(false);
+		    connection.LastUsedHttpClientHandler.UseProxy.Should().BeFalse();
+	    }
+
+	    [U]
+	    public async Task HttpClientUseProxyShouldBeTrueWhenEnabledAutoProxyDetection()
+	    {
+		    var connection = new TestableHttpConnection();
+		    var requestData = CreateRequestData();
+
+		    connection.Request<string>(requestData);
+		    connection.LastUsedHttpClientHandler.UseProxy.Should().BeTrue();
+
+		    await connection.RequestAsync<string>(requestData, CancellationToken.None).ConfigureAwait(false);
+		    connection.LastUsedHttpClientHandler.UseProxy.Should().BeTrue();
+	    }
     }
 }
 #endif