#2139 Add ListenLocalhost and ListenAnyIP

samples/SampleApp/Startup.cs

@@ -76,6 +76,13 @@ namespace SampleApp
                         listenOptions.UseConnectionLogging();
                     });
 
+                    options.ListenLocalhost(basePort + 2, listenOptions =>
+                    {
+                        listenOptions.UseHttps("testCert.pfx", "testPassword");
+                    });
+
+                    options.ListenAnyIP(basePort + 3);
+
                     options.UseSystemd();
 
                     // The following section should be used to demo sockets

src/Kestrel.Core/AnyIPListenOptions.cs

@@ -0,0 +1,37 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using System;
+using System.IO;
+using System.Net;
+using System.Threading.Tasks;
+using Microsoft.AspNetCore.Server.Kestrel.Core.Internal;
+using Microsoft.Extensions.Logging;
+
+namespace Microsoft.AspNetCore.Server.Kestrel.Core
+{
+    internal class AnyIPListenOptions : ListenOptions
+    {
+        internal AnyIPListenOptions(int port)
+            : base(new IPEndPoint(IPAddress.IPv6Any, port))
+        {
+        }
+
+        internal override async Task BindAsync(AddressBindContext context)
+        {
+            // when address is 'http://hostname:port', 'http://*:port', or 'http://+:port'
+            try
+            {
+                await base.BindAsync(context).ConfigureAwait(false);
+            }
+            catch (Exception ex) when (!(ex is IOException))
+            {
+                context.Logger.LogDebug(CoreStrings.FormatFallbackToIPv4Any(IPEndPoint.Port));
+
+                // for machines that do not support IPv6
+                IPEndPoint = new IPEndPoint(IPAddress.Any, IPEndPoint.Port);
+                await base.BindAsync(context).ConfigureAwait(false);
+            }
+        }
+    }
+}

src/Kestrel.Core/Internal/AddressBindContext.cs

@@ -0,0 +1,21 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using System;
+using System.Collections.Generic;
+using System.Threading.Tasks;
+using Microsoft.Extensions.Logging;
+
+namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal
+{
+    internal class AddressBindContext
+    {
+        public ICollection<string> Addresses { get; set; }
+        public List<ListenOptions> ListenOptions { get; set; }
+        public KestrelServerOptions ServerOptions { get; set; }
+        public ILogger Logger { get; set; }
+        public IDefaultHttpsProvider DefaultHttpsProvider { get; set; }
+
+        public Func<ListenOptions, Task> CreateBinding { get; set; }
+    }
+}

src/Kestrel.Core/Internal/AddressBinder.cs

@@ -47,17 +47,6 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal
             await strategy.BindAsync(context).ConfigureAwait(false);
         }
 
-        private class AddressBindContext
-        {
-            public ICollection<string> Addresses { get; set; }
-            public List<ListenOptions> ListenOptions { get; set; }
-            public KestrelServerOptions ServerOptions { get; set; }
-            public ILogger Logger { get; set; }
-            public IDefaultHttpsProvider DefaultHttpsProvider { get; set; }
-
-            public Func<ListenOptions, Task> CreateBinding { get; set; }
-        }
-
         private static IStrategy CreateStrategy(ListenOptions[] listenOptions, string[] addresses, bool preferAddresses)
         {
             var hasListenOptions = listenOptions.Length > 0;
@@ -109,10 +98,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal
             return true;
         }
 
-        private static Task BindEndpointAsync(IPEndPoint endpoint, AddressBindContext context)
-            => BindEndpointAsync(new ListenOptions(endpoint), context);
-
-        private static async Task BindEndpointAsync(ListenOptions endpoint, AddressBindContext context)
+        internal static async Task BindEndpointAsync(ListenOptions endpoint, AddressBindContext context)
         {
             try
             {
@@ -126,60 +112,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal
             context.ListenOptions.Add(endpoint);
         }
 
-        private static async Task BindLocalhostAsync(ServerAddress address, AddressBindContext context, bool https)
-        {
-            if (address.Port == 0)
-            {
-                throw new InvalidOperationException(CoreStrings.DynamicPortOnLocalhostNotSupported);
-            }
-
-            var exceptions = new List<Exception>();
-
-            try
-            {
-                var options = new ListenOptions(new IPEndPoint(IPAddress.Loopback, address.Port));
-                await BindEndpointAsync(options, context).ConfigureAwait(false);
-                
-                if (https)
-                {
-                    options.KestrelServerOptions = context.ServerOptions;
-                    context.DefaultHttpsProvider.ConfigureHttps(options);
-                }
-            }
-            catch (Exception ex) when (!(ex is IOException))
-            {
-                context.Logger.LogWarning(0, CoreStrings.NetworkInterfaceBindingFailed, address, "IPv4 loopback", ex.Message);
-                exceptions.Add(ex);
-            }
-
-            try
-            {
-                var options = new ListenOptions(new IPEndPoint(IPAddress.IPv6Loopback, address.Port));
-                await BindEndpointAsync(options, context).ConfigureAwait(false);
-
-                if (https)
-                {
-                    options.KestrelServerOptions = context.ServerOptions;
-                    context.DefaultHttpsProvider.ConfigureHttps(options);
-                }
-            }
-            catch (Exception ex) when (!(ex is IOException))
-            {
-                context.Logger.LogWarning(0, CoreStrings.NetworkInterfaceBindingFailed, address, "IPv6 loopback", ex.Message);
-                exceptions.Add(ex);
-            }
-
-            if (exceptions.Count == 2)
-            {
-                throw new IOException(CoreStrings.FormatAddressBindingFailed(address), new AggregateException(exceptions));
-            }
-
-            // If StartLocalhost doesn't throw, there is at least one listener.
-            // The port cannot change for "localhost".
-            context.Addresses.Add(address.ToString());
-        }
-
-        private static async Task BindAddressAsync(string address, AddressBindContext context)
+        internal static ListenOptions ParseAddress(string address, KestrelServerOptions serverOptions, IDefaultHttpsProvider defaultHttpsProvider)
         {
             var parsedAddress = ServerAddress.FromUrl(address);
             var https = false;
@@ -202,47 +135,29 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal
             if (parsedAddress.IsUnixPipe)
             {
                 options = new ListenOptions(parsedAddress.UnixPipePath);
-                await BindEndpointAsync(options, context).ConfigureAwait(false);
-                context.Addresses.Add(options.GetDisplayName());
             }
             else if (string.Equals(parsedAddress.Host, "localhost", StringComparison.OrdinalIgnoreCase))
             {
                 // "localhost" for both IPv4 and IPv6 can't be represented as an IPEndPoint.
-                await BindLocalhostAsync(parsedAddress, context, https).ConfigureAwait(false);
+                options = new LocalhostListenOptions(parsedAddress.Port);
+            }
+            else if (TryCreateIPEndPoint(parsedAddress, out var endpoint))
+            {
+                options = new ListenOptions(endpoint);
             }
             else
             {
-                if (TryCreateIPEndPoint(parsedAddress, out var endpoint))
-                {
-                    options = new ListenOptions(endpoint);
-                    await BindEndpointAsync(options, context).ConfigureAwait(false);
-                }
-                else
-                {
-                    // when address is 'http://hostname:port', 'http://*:port', or 'http://+:port'
-                    try
-                    {
-                        options = new ListenOptions(new IPEndPoint(IPAddress.IPv6Any, parsedAddress.Port));
-                        await BindEndpointAsync(options, context).ConfigureAwait(false);
-                    }
-                    catch (Exception ex) when (!(ex is IOException))
-                    {
-                        context.Logger.LogDebug(CoreStrings.FormatFallbackToIPv4Any(parsedAddress.Port));
-
-                        // for machines that do not support IPv6
-                        options = new ListenOptions(new IPEndPoint(IPAddress.Any, parsedAddress.Port));
-                        await BindEndpointAsync(options, context).ConfigureAwait(false);
-                    }
-                }
-
-                context.Addresses.Add(options.GetDisplayName());
+                // when address is 'http://hostname:port', 'http://*:port', or 'http://+:port'
+                options = new AnyIPListenOptions(parsedAddress.Port);
             }
 
-            if (https && options != null)
+            if (https)
             {
-                options.KestrelServerOptions = context.ServerOptions;
-                context.DefaultHttpsProvider.ConfigureHttps(options);
+                options.KestrelServerOptions = serverOptions;
+                defaultHttpsProvider.ConfigureHttps(options);
             }
+
+            return options;
         }
 
         private interface IStrategy
@@ -256,7 +171,8 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal
             {
                 context.Logger.LogDebug(CoreStrings.BindingToDefaultAddress, Constants.DefaultServerAddress);
 
-                await BindLocalhostAsync(ServerAddress.FromUrl(Constants.DefaultServerAddress), context, https: false).ConfigureAwait(false);
+                await ParseAddress(Constants.DefaultServerAddress, context.ServerOptions, context.DefaultHttpsProvider)
+                    .BindAsync(context).ConfigureAwait(false);
             }
         }
 
@@ -308,9 +224,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal
             {
                 foreach (var endpoint in _endpoints)
                 {
-                    await BindEndpointAsync(endpoint, context).ConfigureAwait(false);
-
-                    context.Addresses.Add(endpoint.GetDisplayName());
+                    await endpoint.BindAsync(context).ConfigureAwait(false);
                 }
             }
         }
@@ -328,7 +242,8 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Internal
             {
                 foreach (var address in _addresses)
                 {
-                    await BindAddressAsync(address, context).ConfigureAwait(false);
+                    await ParseAddress(address, context.ServerOptions, context.DefaultHttpsProvider)
+                        .BindAsync(context).ConfigureAwait(false);
                 }
             }
         }

src/Kestrel.Core/KestrelServerOptions.cs

@@ -105,6 +105,40 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core
             ListenOptions.Add(listenOptions);
         }
 
+        public void ListenLocalhost(int port) => ListenLocalhost(port, options => { });
+
+        public void ListenLocalhost(int port, Action<ListenOptions> configure)
+        {
+            if (configure == null)
+            {
+                throw new ArgumentNullException(nameof(configure));
+            }
+
+            var listenOptions = new LocalhostListenOptions(port)
+            {
+                KestrelServerOptions = this,
+            };
+            configure(listenOptions);
+            ListenOptions.Add(listenOptions);
+        }
+
+        public void ListenAnyIP(int port) => ListenAnyIP(port, options => { });
+
+        public void ListenAnyIP(int port, Action<ListenOptions> configure)
+        {
+            if (configure == null)
+            {
+                throw new ArgumentNullException(nameof(configure));
+            }
+
+            var listenOptions = new AnyIPListenOptions(port)
+            {
+                KestrelServerOptions = this,
+            };
+            configure(listenOptions);
+            ListenOptions.Add(listenOptions);
+        }
+
         /// <summary>
         /// Bind to given Unix domain socket path.
         /// </summary>

src/Kestrel.Core/ListenOptions.cs

@@ -8,6 +8,7 @@ using System.Net;
 using System.Threading.Tasks;
 using Microsoft.AspNetCore.Protocols;
 using Microsoft.AspNetCore.Server.Kestrel.Core.Adapter.Internal;
+using Microsoft.AspNetCore.Server.Kestrel.Core.Internal;
 using Microsoft.AspNetCore.Server.Kestrel.Transport.Abstractions.Internal;
 
 namespace Microsoft.AspNetCore.Server.Kestrel.Core
@@ -140,7 +141,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core
         /// <summary>
         /// Gets the name of this endpoint to display on command-line when the web server starts.
         /// </summary>
-        internal string GetDisplayName()
+        internal virtual string GetDisplayName()
         {
             var scheme = ConnectionAdapters.Any(f => f.IsHttps)
                 ? "https"
@@ -182,5 +183,11 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core
 
             return app;
         }
+
+        internal virtual async Task BindAsync(AddressBindContext context)
+        {
+            await AddressBinder.BindEndpointAsync(this, context).ConfigureAwait(false);
+            context.Addresses.Add(GetDisplayName());
+        }
     }
 }

src/Kestrel.Core/LocalhostListenOptions.cs

@@ -0,0 +1,88 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Net;
+using System.Threading.Tasks;
+using Microsoft.AspNetCore.Server.Kestrel.Core.Internal;
+using Microsoft.Extensions.Logging;
+
+namespace Microsoft.AspNetCore.Server.Kestrel.Core
+{
+    internal class LocalhostListenOptions : ListenOptions
+    {
+        internal LocalhostListenOptions(int port)
+            : base(new IPEndPoint(IPAddress.Loopback, port))
+        {
+            if (port == 0)
+            {
+                throw new InvalidOperationException(CoreStrings.DynamicPortOnLocalhostNotSupported);
+            }
+        }
+
+        /// <summary>
+        /// Gets the name of this endpoint to display on command-line when the web server starts.
+        /// </summary>
+        internal override string GetDisplayName()
+        {
+            var scheme = ConnectionAdapters.Any(f => f.IsHttps)
+                ? "https"
+                : "http";
+
+            return $"{scheme}://localhost:{IPEndPoint.Port}";
+        }
+
+        internal override async Task BindAsync(AddressBindContext context)
+        {
+            var exceptions = new List<Exception>();
+
+            try
+            {
+                var v4Options = Clone(IPAddress.Loopback);
+                await AddressBinder.BindEndpointAsync(v4Options, context).ConfigureAwait(false);
+            }
+            catch (Exception ex) when (!(ex is IOException))
+            {
+                context.Logger.LogWarning(0, CoreStrings.NetworkInterfaceBindingFailed, GetDisplayName(), "IPv4 loopback", ex.Message);
+                exceptions.Add(ex);
+            }
+
+            try
+            {
+                var v6Options = Clone(IPAddress.IPv6Loopback);
+                await AddressBinder.BindEndpointAsync(v6Options, context).ConfigureAwait(false);
+            }
+            catch (Exception ex) when (!(ex is IOException))
+            {
+                context.Logger.LogWarning(0, CoreStrings.NetworkInterfaceBindingFailed, GetDisplayName(), "IPv6 loopback", ex.Message);
+                exceptions.Add(ex);
+            }
+
+            if (exceptions.Count == 2)
+            {
+                throw new IOException(CoreStrings.FormatAddressBindingFailed(GetDisplayName()), new AggregateException(exceptions));
+            }
+
+            // If StartLocalhost doesn't throw, there is at least one listener.
+            // The port cannot change for "localhost".
+            context.Addresses.Add(GetDisplayName());
+        }
+
+        // used for cloning to two IPEndpoints
+        private ListenOptions Clone(IPAddress address)
+        {
+            var options = new ListenOptions(new IPEndPoint(address, IPEndPoint.Port))
+            {
+                HandleType = HandleType,
+                KestrelServerOptions = KestrelServerOptions,
+                NoDelay = NoDelay,
+                Protocols = Protocols,
+            };
+            options.ConnectionAdapters.AddRange(ConnectionAdapters);
+            return options;
+        }
+    }
+}

test/Kestrel.Core.Tests/AddressBinderTests.cs

@@ -2,12 +2,12 @@
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
 using System;
-using System.Collections.Generic;
 using System.IO;
 using System.Net;
 using System.Threading.Tasks;
 using Microsoft.AspNetCore.Protocols;
 using Microsoft.AspNetCore.Server.Kestrel.Core.Internal;
+using Microsoft.AspNetCore.Server.Kestrel.Transport.Abstractions.Internal;
 using Microsoft.AspNetCore.Testing;
 using Microsoft.Extensions.Logging.Abstractions;
 using Moq;
@@ -51,24 +51,49 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Core.Tests
         [InlineData("randomhost")]
         [InlineData("+")]
         [InlineData("contoso.com")]
-        public async Task DefaultsToIPv6AnyOnInvalidIPAddress(string host)
+        public void ParseAddressDefaultsToAnyIPOnInvalidIPAddress(string host)
         {
-            var addresses = new ServerAddressesFeature();
-            addresses.Addresses.Add($"http://{host}");
             var options = new KestrelServerOptions();
+            var listenOptions = AddressBinder.ParseAddress($"http://{host}", options, Mock.Of<IDefaultHttpsProvider>());
+            Assert.IsType<AnyIPListenOptions>(listenOptions);
+            Assert.Equal(ListenType.IPEndPoint, listenOptions.Type);
+            Assert.Equal(IPAddress.IPv6Any, listenOptions.IPEndPoint.Address);
+            Assert.Equal(80, listenOptions.IPEndPoint.Port);
+        }
 
-            var tcs = new TaskCompletionSource<ListenOptions>();
-            await AddressBinder.BindAsync(addresses,
-                options,
-                NullLogger.Instance,
-                Mock.Of<IDefaultHttpsProvider>(),
-                endpoint =>
-                {
-                    tcs.TrySetResult(endpoint);
-                    return Task.CompletedTask;
-                });
-            var result = await tcs.Task;
-            Assert.Equal(IPAddress.IPv6Any, result.IPEndPoint.Address);
+        [Fact]
+        public void ParseAddressLocalhost()
+        {
+            var options = new KestrelServerOptions();
+            var listenOptions = AddressBinder.ParseAddress("http://localhost", options, Mock.Of<IDefaultHttpsProvider>());
+            Assert.IsType<LocalhostListenOptions>(listenOptions);
+            Assert.Equal(ListenType.IPEndPoint, listenOptions.Type);
+            Assert.Equal(IPAddress.Loopback, listenOptions.IPEndPoint.Address);
+            Assert.Equal(80, listenOptions.IPEndPoint.Port);
+        }
+
+        [Fact]
+        public void ParseAddressUnixPipe()
+        {
+            var options = new KestrelServerOptions();
+            var listenOptions = AddressBinder.ParseAddress("http://unix:/tmp/kestrel-test.sock", options, Mock.Of<IDefaultHttpsProvider>());
+            Assert.Equal(ListenType.SocketPath, listenOptions.Type);
+            Assert.Equal("/tmp/kestrel-test.sock", listenOptions.SocketPath);
+        }
+
+        [Theory]
+        [InlineData("http://10.10.10.10:5000/", "10.10.10.10", 5000)]
+        [InlineData("http://[::1]:5000", "::1", 5000)]
+        [InlineData("http://[::1]", "::1", 80)]
+        [InlineData("http://127.0.0.1", "127.0.0.1", 80)]
+        [InlineData("https://127.0.0.1", "127.0.0.1", 443)]
+        public void ParseAddressIP(string address, string ip, int port)
+        {
+            var options = new KestrelServerOptions();
+            var listenOptions = AddressBinder.ParseAddress(address, options, Mock.Of<IDefaultHttpsProvider>());
+            Assert.Equal(ListenType.IPEndPoint, listenOptions.Type);
+            Assert.Equal(IPAddress.Parse(ip), listenOptions.IPEndPoint.Address);
+            Assert.Equal(port, listenOptions.IPEndPoint.Port);
         }
 
         [Fact]

test/Kestrel.FunctionalTests/AddressRegistrationTests.cs

@@ -187,7 +187,10 @@ namespace Microsoft.AspNetCore.Server.Kestrel.FunctionalTests
         private Task RegisterAddresses_Success(string addressInput, string testUrl, int testPort = 0)
             => RegisterAddresses_Success(addressInput, new[] { testUrl }, testPort);
 
-        private async Task RegisterAddresses_StaticPort_Success(string addressInput, string[] testUrls)
+        private Task RegisterAddresses_StaticPort_Success(string addressInput, string[] testUrls) =>
+            RunTestWithStaticPort(port => RegisterAddresses_Success($"{addressInput}:{port}", testUrls, port));
+
+        private async Task RunTestWithStaticPort(Func<int, Task> test)
         {
             var retryCount = 0;
             var errors = new List<Exception>();
@@ -197,7 +200,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.FunctionalTests
                 try
                 {
                     var port = GetNextPort();
-                    await RegisterAddresses_Success($"{addressInput}:{port}", testUrls, port);
+                    await test(port);
                     return;
                 }
                 catch (XunitException)
@@ -254,34 +257,93 @@ namespace Microsoft.AspNetCore.Server.Kestrel.FunctionalTests
             }
         }
 
-        private async Task RegisterIPEndPoint_StaticPort_Success(IPAddress address, string testUrl)
+        private Task RegisterIPEndPoint_StaticPort_Success(IPAddress address, string testUrl)
+            => RunTestWithStaticPort(port => RegisterIPEndPoint_Success(new IPEndPoint(address, port), testUrl, port));
+
+        [ConditionalFact]
+        public async Task ListenAnyIP_IPv4_Success()
         {
-            var retryCount = 0;
-            var errors = new List<Exception>();
+            await ListenAnyIP_Success(new[] { "http://localhost", "http://127.0.0.1" });
+        }
 
-            while (retryCount < MaxRetries)
+        [ConditionalFact]
+        [IPv6SupportedCondition]
+        public async Task ListenAnyIP_IPv6_Success()
+        {
+            await ListenAnyIP_Success(new[] { "http://[::1]", "http://localhost", "http://127.0.0.1" });
+        }
+
+        [ConditionalFact]
+        [NetworkIsReachable]
+        public async Task ListenAnyIP_HostName_Success()
+        {
+            var hostName = Dns.GetHostName();
+            await ListenAnyIP_Success(new[] { $"http://{hostName}" });
+        }
+
+        private async Task ListenAnyIP_Success(string[] testUrls, int testPort = 0)
+        {
+            var hostBuilder = TransportSelector.GetWebHostBuilder()
+                .UseKestrel(options =>
+                {
+                    options.ListenAnyIP(testPort);
+                })
+                .ConfigureLogging(_configureLoggingDelegate)
+                .Configure(ConfigureEchoAddress);
+
+            using (var host = hostBuilder.Build())
             {
-                try
-                {
-                    var port = GetNextPort();
-                    await RegisterIPEndPoint_Success(new IPEndPoint(address, port), testUrl, port);
-                    return;
-                }
-                catch (XunitException)
-                {
-                    throw;
-                }
-                catch (Exception ex)
-                {
-                    errors.Add(ex);
-                }
+                host.Start();
 
-                retryCount++;
+                foreach (var testUrl in testUrls.Select(testUrl => $"{testUrl}:{(testPort == 0 ? host.GetPort() : testPort)}"))
+                {
+                    var response = await HttpClientSlim.GetStringAsync(testUrl, validateCertificate: false);
+
+                    // Compare the response with Uri.ToString(), rather than testUrl directly.
+                    // Required to handle IPv6 addresses with zone index, like "fe80::3%1"
+                    Assert.Equal(new Uri(testUrl).ToString(), response);
+                }
             }
+        }
 
-            if (errors.Any())
+        [ConditionalFact]
+        public async Task ListenLocalhost_IPv4LocalhostStaticPort_Success()
+        {
+            await ListenLocalhost_StaticPort_Success(new[] { "http://localhost", "http://127.0.0.1" });
+        }
+
+        [ConditionalFact]
+        [IPv6SupportedCondition]
+        public async Task ListenLocalhost_IPv6LocalhostStaticPort_Success()
+        {
+            await ListenLocalhost_StaticPort_Success(new[] { "http://localhost", "http://127.0.0.1", "http://[::1]" });
+        }
+
+        private Task ListenLocalhost_StaticPort_Success(string[] testUrls) =>
+            RunTestWithStaticPort(port => ListenLocalhost_Success(testUrls, port));
+
+        private async Task ListenLocalhost_Success(string[] testUrls, int testPort = 0)
+        {
+            var hostBuilder = TransportSelector.GetWebHostBuilder()
+                .UseKestrel(options =>
+                {
+                    options.ListenLocalhost(testPort);
+                })
+                .ConfigureLogging(_configureLoggingDelegate)
+                .Configure(ConfigureEchoAddress);
+
+            using (var host = hostBuilder.Build())
             {
-                throw new AggregateException(errors);
+                host.Start();
+
+                foreach (var testUrl in testUrls.Select(testUrl => $"{testUrl}:{(testPort == 0 ? host.GetPort() : testPort)}"))
+                {
+                    var response = await HttpClientSlim.GetStringAsync(testUrl, validateCertificate: false);
+
+                    // Compare the response with Uri.ToString(), rather than testUrl directly.
+                    // Required to handle IPv6 addresses with zone index, like "fe80::3%1"
+                    Assert.Equal(new Uri(testUrl).ToString(), response);
+                }
             }
         }
 

test/Kestrel.Transport.Libuv.Tests/LibuvOutputConsumerTests.cs

@@ -41,7 +41,7 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Transport.Libuv.Tests
             _bufferPool = new MemoryPool();
             _mockLibuv = new MockLibuv();
 
-            var libuvTransport = new LibuvTransport(_mockLibuv, new TestLibuvTransportContext(), new ListenOptions(0));
+            var libuvTransport = new LibuvTransport(_mockLibuv, new TestLibuvTransportContext(), new ListenOptions((ulong)0));
             _libuvThread = new LibuvThread(libuvTransport, maxLoops: 1);
             _libuvThread.StartAsync().Wait();
         }