Add extension library for WebSocket4Net usage.

Build/MQTTnet.Extensions.WebSocket4Net.nuspec

@@ -0,0 +1,42 @@
+<?xml version="1.0"?>
+<package >
+  <metadata>
+    <id>MQTTnet.Extensions.WebSocket4Net</id>
+    <version>0.0.0</version>
+    <authors>Christian Kratky</authors>
+    <owners>Christian Kratky</owners>
+    <license type="file">LICENSE</license>
+    <projectUrl>https://github.com/chkr1011/MQTTnet</projectUrl>
+    <iconUrl>https://raw.githubusercontent.com/chkr1011/MQTTnet/master/Images/Logo_128x128.png</iconUrl>
+    <requireLicenseAcceptance>false</requireLicenseAcceptance>
+    <description>This is an extension library which allows using _WebSocket4Net_ as transport for MQTTnet clients.</description>
+    <releaseNotes>For release notes please go to MQTTnet release notes (https://www.nuget.org/packages/MQTTnet/).</releaseNotes>
+    <copyright>Copyright Christian Kratky 2016-2019</copyright>
+    <tags>MQTT Message Queue Telemetry Transport MQTTClient MQTTServer Server MQTTBroker Broker NETStandard IoT InternetOfThings Messaging Hardware Arduino Sensor Actuator M2M ESP Smart Home Cities Automation Xamarin</tags> 
+    <dependencies>
+      <dependency id="MQTTnet" version="$nugetVersion" />
+    </dependencies>
+  </metadata>
+
+  <files>
+    <!-- License -->
+    <file src="..\LICENSE" />
+
+    <!-- .NET Standard 1.3 -->
+    <file src="..\Source\MQTTnet.Extensions.WebSocket4Net\bin\Release\netstandard1.3\MQTTnet.Extensions.WebSocket4Net.*" target="lib\netstandard1.3\"/>
+
+    <!-- .NET Standard 2.0 -->
+    <file src="..\Source\MQTTnet.Extensions.WebSocket4Net\bin\Release\netstandard2.0\MQTTnet.Extensions.WebSocket4Net.*" target="lib\netstandard2.0\"/>
+
+    <!-- Universal Windows -->
+    <file src="..\Source\MQTTnet.Extensions.WebSocket4Net\bin\Release\uap10.0\MQTTnet.Extensions.WebSocket4Net.*" target="lib\uap10.0\"/>
+
+    <!-- .NET Framework -->
+    <file src="..\Source\MQTTnet.Extensions.WebSocket4Net\bin\Release\net452\MQTTnet.Extensions.WebSocket4Net.*" target="lib\net452\"/>
+
+    <!-- .NET Framework 4.6.0 will use binaries from 4.5.2. -->
+    <file src="..\Source\MQTTnet.Extensions.WebSocket4Net\bin\Release\net461\MQTTnet.Extensions.WebSocket4Net.*" target="lib\net461\"/>
+
+    <!-- Everything above .NET Framework 4.6.1 will use the binaries from 4.6.1. -->
+  </files>
+</package>

Build/MQTTnet.nuspec

@@ -12,6 +12,7 @@
     <description>MQTTnet is a high performance .NET library for MQTT based communication. It provides a MQTT client and a MQTT server (broker).</description>
     <releaseNotes>
 * [Core] Fixed issues in MQTTv5 message encoding and decoding.
+* [Core] Added extension method to allow usage of _WebSocket4Net_ in clients to fix issues with AWS and Xamarin.
 * [Client] Added support for extended authentication exchange.
 * [Client] Exposed MQTTv5 CONNACK values to client.
 * [Client] Added _MqttClientSubscribeOptionsBuilder_.

Build/build.ps1

@@ -36,6 +36,14 @@ Write-Host
 &$msbuild ..\Source\MQTTnet.Extensions.ManagedClient\MQTTnet.Extensions.ManagedClient.csproj /t:Build /p:Configuration="Release" /p:TargetFramework="netstandard2.0" /p:FileVersion=$assemblyVersion /p:AssemblyVersion=$assemblyVersion /verbosity:m /p:SignAssembly=true /p:AssemblyOriginatorKeyFile=".\..\..\Build\codeSigningKey.pfx"
 &$msbuild ..\Source\MQTTnet.Extensions.ManagedClient\MQTTnet.Extensions.ManagedClient.csproj /t:Build /p:Configuration="Release" /p:TargetFramework="uap10.0" /p:FileVersion=$assemblyVersion /p:AssemblyVersion=$assemblyVersion /verbosity:m /p:SignAssembly=true /p:AssemblyOriginatorKeyFile=".\..\..\Build\codeSigningKey.pfx"
 
+# Build the WebSocket4Net extension
+&$msbuild ..\Source\MQTTnet.Extensions.WebSocket4Net\MQTTnet.Extensions.WebSocket4Net.csproj /t:Build /p:Configuration="Release" /p:TargetFramework="net452" /p:FileVersion=$assemblyVersion /p:AssemblyVersion=$assemblyVersion /verbosity:m /p:SignAssembly=true /p:AssemblyOriginatorKeyFile=".\..\..\Build\codeSigningKey.pfx"
+&$msbuild ..\Source\MQTTnet.Extensions.WebSocket4Net\MQTTnet.Extensions.WebSocket4Net.csproj /t:Build /p:Configuration="Release" /p:TargetFramework="net461" /p:FileVersion=$assemblyVersion /p:AssemblyVersion=$assemblyVersion /verbosity:m /p:SignAssembly=true /p:AssemblyOriginatorKeyFile=".\..\..\Build\codeSigningKey.pfx"
+&$msbuild ..\Source\MQTTnet.Extensions.WebSocket4Net\MQTTnet.Extensions.WebSocket4Net.csproj /t:Build /p:Configuration="Release" /p:TargetFramework="netstandard1.3" /p:FileVersion=$assemblyVersion /p:AssemblyVersion=$assemblyVersion /verbosity:m /p:SignAssembly=true /p:AssemblyOriginatorKeyFile=".\..\..\Build\codeSigningKey.pfx"
+&$msbuild ..\Source\MQTTnet.Extensions.WebSocket4Net\MQTTnet.Extensions.WebSocket4Net.csproj /t:Build /p:Configuration="Release" /p:TargetFramework="netstandard2.0" /p:FileVersion=$assemblyVersion /p:AssemblyVersion=$assemblyVersion /verbosity:m /p:SignAssembly=true /p:AssemblyOriginatorKeyFile=".\..\..\Build\codeSigningKey.pfx"
+&$msbuild ..\Source\MQTTnet.Extensions.WebSocket4Net\MQTTnet.Extensions.WebSocket4Net.csproj /t:Build /p:Configuration="Release" /p:TargetFramework="uap10.0" /p:FileVersion=$assemblyVersion /p:AssemblyVersion=$assemblyVersion /verbosity:m /p:SignAssembly=true /p:AssemblyOriginatorKeyFile=".\..\..\Build\codeSigningKey.pfx"
+
+
 # Build MQTTnet.Server
 Remove-Item ..\Source\MQTTnet.Server\bin\Release\netcoreapp2.2 -Recurse -Force -ErrorAction SilentlyContinue
 &$msbuild ..\Source\MQTTnet.Server\MQTTnet.Server.csproj /t:Build /p:Configuration="Release" /p:TargetFramework="netcoreapp2.2" /p:publishprofile=FolderProfile /p:deployonbuild=true /p:FileVersion=$assemblyVersion /p:AssemblyVersion=$assemblyVersion /verbosity:m /p:SignAssembly=true /p:AssemblyOriginatorKeyFile=".\..\..\Build\codeSigningKey.pfx"
@@ -55,6 +63,8 @@ Copy-Item MQTTnet.Extensions.Rpc.nuspec -Destination MQTTnet.Extensions.Rpc.nusp
 (Get-Content MQTTnet.Extensions.Rpc.nuspec) -replace '\$nugetVersion', $nugetVersion | Set-Content MQTTnet.Extensions.Rpc.nuspec
 Copy-Item MQTTnet.Extensions.ManagedClient.nuspec -Destination MQTTnet.Extensions.ManagedClient.nuspec.old -Force
 (Get-Content MQTTnet.Extensions.ManagedClient.nuspec) -replace '\$nugetVersion', $nugetVersion | Set-Content MQTTnet.Extensions.ManagedClient.nuspec
+Copy-Item MQTTnet.Extensions.WebSocket4Net.nuspec -Destination MQTTnet.Extensions.WebSocket4Net.nuspec.old -Force
+(Get-Content MQTTnet.Extensions.WebSocket4Net.nuspec) -replace '\$nugetVersion', $nugetVersion | Set-Content MQTTnet.Extensions.WebSocket4Net.nuspec
 
 New-Item -ItemType Directory -Force -Path .\NuGet
 .\nuget.exe pack MQTTnet.nuspec -Verbosity detailed -Symbols -OutputDir "NuGet" -Version $nugetVersion
@@ -62,7 +72,9 @@ New-Item -ItemType Directory -Force -Path .\NuGet
 .\nuget.exe pack MQTTnet.AspNetCore.nuspec -Verbosity detailed -Symbols -OutputDir "NuGet" -Version $nugetVersion
 .\nuget.exe pack MQTTnet.Extensions.Rpc.nuspec -Verbosity detailed -Symbols -OutputDir "NuGet" -Version $nugetVersion
 .\nuget.exe pack MQTTnet.Extensions.ManagedClient.nuspec -Verbosity detailed -Symbols -OutputDir "NuGet" -Version $nugetVersion
+.\nuget.exe pack MQTTnet.Extensions.WebSocket4Net.nuspec -Verbosity detailed -Symbols -OutputDir "NuGet" -Version $nugetVersion
 
 Move-Item MQTTnet.AspNetCore.nuspec.old -Destination MQTTnet.AspNetCore.nuspec -Force
 Move-Item MQTTnet.Extensions.Rpc.nuspec.old -Destination MQTTnet.Extensions.Rpc.nuspec -Force
-Move-Item MQTTnet.Extensions.ManagedClient.nuspec.old -Destination MQTTnet.Extensions.ManagedClient.nuspec -Force
+Move-Item MQTTnet.Extensions.ManagedClient.nuspec.old -Destination MQTTnet.Extensions.ManagedClient.nuspec -Force
+Move-Item MQTTnet.Extensions.WebSocket4Net.nuspec.old -Destination MQTTnet.Extensions.WebSocket4Net.nuspec -Force

MQTTnet.sln

@@ -19,6 +19,7 @@ Project("{2150E333-8FDC-42A3-9474-1A3956D46DE8}") = "Build", "Build", "{67C28AC1
 		Build\MQTTnet.AspNetCore.nuspec = Build\MQTTnet.AspNetCore.nuspec
 		Build\MQTTnet.Extensions.ManagedClient.nuspec = Build\MQTTnet.Extensions.ManagedClient.nuspec
 		Build\MQTTnet.Extensions.Rpc.nuspec = Build\MQTTnet.Extensions.Rpc.nuspec
+		Build\MQTTnet.Extensions.WebSocket4Net.nuspec = Build\MQTTnet.Extensions.WebSocket4Net.nuspec
 		Build\MQTTnet.NETStandard.nuspec = Build\MQTTnet.NETStandard.nuspec
 		Build\MQTTnet.nuspec = Build\MQTTnet.nuspec
 		Build\upload.ps1 = Build\upload.ps1
@@ -50,6 +51,8 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "MQTTnet.AspNetCore.Tests",
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "MQTTnet.Server", "Source\MQTTnet.Server\MQTTnet.Server.csproj", "{5699FB8C-838C-4AB0-80A5-9CA809F9B65B}"
 EndProject
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "MQTTnet.Extensions.WebSocket4Net", "Source\MQTTnet.Extensions.WebSocket4Net\MQTTnet.Extensions.WebSocket4Net.csproj", "{2BD01D53-4CA5-4142-BE8D-313876395E3E}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -245,6 +248,22 @@ Global
 		{5699FB8C-838C-4AB0-80A5-9CA809F9B65B}.Release|x64.Build.0 = Release|Any CPU
 		{5699FB8C-838C-4AB0-80A5-9CA809F9B65B}.Release|x86.ActiveCfg = Release|Any CPU
 		{5699FB8C-838C-4AB0-80A5-9CA809F9B65B}.Release|x86.Build.0 = Release|Any CPU
+		{2BD01D53-4CA5-4142-BE8D-313876395E3E}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{2BD01D53-4CA5-4142-BE8D-313876395E3E}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{2BD01D53-4CA5-4142-BE8D-313876395E3E}.Debug|ARM.ActiveCfg = Debug|Any CPU
+		{2BD01D53-4CA5-4142-BE8D-313876395E3E}.Debug|ARM.Build.0 = Debug|Any CPU
+		{2BD01D53-4CA5-4142-BE8D-313876395E3E}.Debug|x64.ActiveCfg = Debug|Any CPU
+		{2BD01D53-4CA5-4142-BE8D-313876395E3E}.Debug|x64.Build.0 = Debug|Any CPU
+		{2BD01D53-4CA5-4142-BE8D-313876395E3E}.Debug|x86.ActiveCfg = Debug|Any CPU
+		{2BD01D53-4CA5-4142-BE8D-313876395E3E}.Debug|x86.Build.0 = Debug|Any CPU
+		{2BD01D53-4CA5-4142-BE8D-313876395E3E}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{2BD01D53-4CA5-4142-BE8D-313876395E3E}.Release|Any CPU.Build.0 = Release|Any CPU
+		{2BD01D53-4CA5-4142-BE8D-313876395E3E}.Release|ARM.ActiveCfg = Release|Any CPU
+		{2BD01D53-4CA5-4142-BE8D-313876395E3E}.Release|ARM.Build.0 = Release|Any CPU
+		{2BD01D53-4CA5-4142-BE8D-313876395E3E}.Release|x64.ActiveCfg = Release|Any CPU
+		{2BD01D53-4CA5-4142-BE8D-313876395E3E}.Release|x64.Build.0 = Release|Any CPU
+		{2BD01D53-4CA5-4142-BE8D-313876395E3E}.Release|x86.ActiveCfg = Release|Any CPU
+		{2BD01D53-4CA5-4142-BE8D-313876395E3E}.Release|x86.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
@@ -261,6 +280,7 @@ Global
 		{C400533A-8EBA-4F0B-BF4D-295C3708604B} = {12816BCC-AF9E-44A9-9AE5-C246AF2A0587}
 		{61B62223-F5D0-48E4-BBD6-2CBA9353CB5E} = {9248C2E1-B9D6-40BF-81EC-86004D7765B4}
 		{5699FB8C-838C-4AB0-80A5-9CA809F9B65B} = {32A630A7-2598-41D7-B625-204CD906F5FB}
+		{2BD01D53-4CA5-4142-BE8D-313876395E3E} = {12816BCC-AF9E-44A9-9AE5-C246AF2A0587}
 	EndGlobalSection
 	GlobalSection(ExtensibilityGlobals) = postSolution
 		SolutionGuid = {07536672-5CBC-4BE3-ACE0-708A431A7894}

Source/MQTTnet.Extensions.WebSocket4Net/MQTTnet.Extensions.WebSocket4Net.csproj

@@ -0,0 +1,34 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFrameworks>netstandard1.3;netstandard2.0</TargetFrameworks>
+    <TargetFrameworks Condition=" '$(OS)' == 'Windows_NT' ">$(TargetFrameworks);net452;net461</TargetFrameworks>
+    <TargetFrameworks Condition=" '$(OS)' == 'Windows_NT' AND '$(MSBuildRuntimeType)' != 'Core'">$(TargetFrameworks);uap10.0</TargetFrameworks>
+    <Product />
+    <Company />
+    <Authors />
+    <PackageId />
+  </PropertyGroup>
+
+  <PropertyGroup Condition="'$(TargetFramework)' == 'uap10.0'">
+    <CopyLocalLockFileAssemblies>false</CopyLocalLockFileAssemblies>
+    <NugetTargetMoniker>UAP,Version=v10.0</NugetTargetMoniker>
+    <TargetPlatformIdentifier>UAP</TargetPlatformIdentifier>
+    <TargetPlatformVersion>10.0.17134.0</TargetPlatformVersion>
+    <TargetPlatformMinVersion>10.0.10240.0</TargetPlatformMinVersion>
+    <TargetFrameworkIdentifier>.NETCore</TargetFrameworkIdentifier>
+    <TargetFrameworkVersion>v5.0</TargetFrameworkVersion>
+    <DefineConstants>$(DefineConstants);WINDOWS_UWP</DefineConstants>
+    <DefaultLanguage>en</DefaultLanguage>
+    <LanguageTargets>$(MSBuildExtensionsPath)\Microsoft\WindowsXaml\v$(VisualStudioVersion)\Microsoft.Windows.UI.Xaml.CSharp.targets</LanguageTargets>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="WebSocket4Net" Version="0.15.2" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\MQTTnet\MQTTnet.csproj" />
+  </ItemGroup>
+
+</Project>

Source/MQTTnet.Extensions.WebSocket4Net/MqttFactoryExtensions.cs

@@ -0,0 +1,14 @@
+using System;
+
+namespace MQTTnet.Extensions.WebSocket4Net
+{
+    public static class MqttFactoryExtensions
+    {
+        public static IMqttFactory UseWebSocket4Net(this IMqttFactory mqttFactory)
+        {
+            if (mqttFactory == null) throw new ArgumentNullException(nameof(mqttFactory));
+
+            return mqttFactory.UseClientAdapterFactory(new WebSocket4NetMqttClientAdapterFactory());
+        }
+    }
+}

Source/MQTTnet.Extensions.WebSocket4Net/WebSocket4NetMqttChannel.cs

@@ -0,0 +1,231 @@
+using System;
+using System.Collections.Concurrent;
+using System.Collections.Generic;
+using System.Linq;
+using System.Net;
+using System.Security.Authentication;
+using System.Security.Cryptography.X509Certificates;
+using System.Threading;
+using System.Threading.Tasks;
+using MQTTnet.Channel;
+using MQTTnet.Client.Options;
+using MQTTnet.Exceptions;
+using MQTTnet.Internal;
+using SuperSocket.ClientEngine;
+using WebSocket4Net;
+
+namespace MQTTnet.Extensions.WebSocket4Net
+{
+    public class WebSocket4NetMqttChannel : IMqttChannel
+    {
+        private readonly BlockingCollection<byte> _receiveBuffer = new BlockingCollection<byte>();
+
+        private readonly IMqttClientOptions _clientOptions;
+        private readonly MqttClientWebSocketOptions _webSocketOptions;
+
+        private WebSocket _webSocket;
+
+        public WebSocket4NetMqttChannel(IMqttClientOptions clientOptions, MqttClientWebSocketOptions webSocketOptions)
+        {
+            _clientOptions = clientOptions ?? throw new ArgumentNullException(nameof(clientOptions));
+            _webSocketOptions = webSocketOptions ?? throw new ArgumentNullException(nameof(webSocketOptions));
+        }
+
+        public string Endpoint => _webSocketOptions.Uri;
+
+        public bool IsSecureConnection { get; private set; }
+
+        public async Task ConnectAsync(CancellationToken cancellationToken)
+        {
+            var uri = _webSocketOptions.Uri;
+            if (!uri.StartsWith("ws://", StringComparison.OrdinalIgnoreCase) && !uri.StartsWith("wss://", StringComparison.OrdinalIgnoreCase))
+            {
+                if (_webSocketOptions.TlsOptions?.UseTls == false)
+                {
+                    uri = "ws://" + uri;
+                }
+                else
+                {
+                    uri = "wss://" + uri;
+                }
+            }
+
+            var sslProtocols = _webSocketOptions?.TlsOptions?.SslProtocol ?? SslProtocols.None;
+            var subProtocol = _webSocketOptions.SubProtocols.FirstOrDefault() ?? string.Empty;
+
+            var cookies = new List<KeyValuePair<string, string>>();
+            if (_webSocketOptions.CookieContainer != null)
+            {
+                throw new NotSupportedException("Cookies are not supported.");
+            }
+
+            List<KeyValuePair<string, string>> customHeaders = null;
+            if (_webSocketOptions.RequestHeaders != null)
+            {
+                customHeaders = _webSocketOptions.RequestHeaders.Select(i => new KeyValuePair<string, string>(i.Key, i.Value)).ToList();
+            }
+
+            EndPoint proxy = null;
+            if (_webSocketOptions.ProxyOptions != null)
+            {
+                throw new NotSupportedException("Proxies are not supported.");
+            }
+
+            // The user agent can be empty always because it is just added to the custom headers as "User-Agent".
+            var userAgent = string.Empty;
+
+            var origin = string.Empty;
+            var webSocketVersion = WebSocketVersion.None;
+            var receiveBufferSize = 0;
+
+            var certificates = new X509CertificateCollection();
+            if (_webSocketOptions?.TlsOptions?.Certificates != null)
+            {
+                foreach (var certificate in _webSocketOptions.TlsOptions.Certificates)
+                {
+                    certificates.Add(new X509Certificate(certificate));
+                }
+            }
+
+            _webSocket = new WebSocket(uri, subProtocol, cookies, customHeaders, userAgent, origin, webSocketVersion, proxy, sslProtocols, receiveBufferSize)
+            {
+                NoDelay = true,
+                Security =
+                {
+                    AllowUnstrustedCertificate = _webSocketOptions?.TlsOptions?.AllowUntrustedCertificates == true,
+                    AllowCertificateChainErrors = _webSocketOptions?.TlsOptions?.IgnoreCertificateChainErrors == true,
+                    Certificates = certificates
+                }
+            };
+
+            await ConnectInternalAsync(cancellationToken).ConfigureAwait(false);
+            
+            IsSecureConnection = uri.StartsWith("wss://", StringComparison.OrdinalIgnoreCase);
+        }
+
+        public Task DisconnectAsync(CancellationToken cancellationToken)
+        {
+            if (_webSocket != null && _webSocket.State == WebSocketState.Open)
+            {
+                _webSocket.Close();
+            }
+            
+            return Task.FromResult(0);
+        }
+
+        public Task<int> ReadAsync(byte[] buffer, int offset, int count, CancellationToken cancellationToken)
+        {
+            var readBytes = 0;
+            while (count > 0 && !cancellationToken.IsCancellationRequested)
+            {
+                if (!_receiveBuffer.TryTake(out var @byte))
+                {
+                    if (readBytes == 0)
+                    {
+                        // Block until at least one byte was received.
+                        @byte = _receiveBuffer.Take(cancellationToken);
+                    }
+                    else
+                    {
+                        return Task.FromResult(readBytes);
+                    }
+                }
+
+                buffer[offset] = @byte;
+                offset++;
+                count--;
+                readBytes++;
+            }
+
+            return Task.FromResult(readBytes);
+        }
+
+        public Task WriteAsync(byte[] buffer, int offset, int count, CancellationToken cancellationToken)
+        {
+            _webSocket.Send(buffer, offset, count);
+            return Task.FromResult(0);
+        }
+
+        public void Dispose()
+        {
+            if (_webSocket == null)
+            {
+                return;
+            }
+
+            _webSocket.DataReceived -= OnDataReceived;
+            _webSocket.Error -= OnError;
+            _webSocket.Dispose();
+            _webSocket = null;
+        }
+
+        private void OnError(object sender, ErrorEventArgs e)
+        {
+            System.Diagnostics.Debug.Write(e.Exception.ToString());
+        }
+
+        private void OnDataReceived(object sender, DataReceivedEventArgs e)
+        {
+            foreach (var @byte in e.Data)
+            {
+                _receiveBuffer.Add(@byte);
+            }
+        }
+
+        private async Task ConnectInternalAsync(CancellationToken cancellationToken)
+        {
+            _webSocket.Error += OnError;
+            _webSocket.DataReceived += OnDataReceived;
+
+            var taskCompletionSource = new TaskCompletionSource<Exception>();
+
+            void ErrorHandler(object sender, ErrorEventArgs e)
+            {
+                taskCompletionSource.TrySetResult(e.Exception);
+            }
+
+            void SuccessHandler(object sender, EventArgs e)
+            {
+                taskCompletionSource.TrySetResult(null);
+            }
+
+            try
+            {
+                _webSocket.Opened += SuccessHandler;
+                _webSocket.Error += ErrorHandler;
+
+                _webSocket.Open();
+
+                var exception = await MqttTaskTimeout.WaitAsync(c =>
+                {
+                    c.Register(() => taskCompletionSource.TrySetCanceled());
+                    return taskCompletionSource.Task;
+                }, _clientOptions.CommunicationTimeout, cancellationToken).ConfigureAwait(false);
+
+                if (exception != null)
+                {
+                    if (exception is AuthenticationException authenticationException)
+                    {
+                        throw new MqttCommunicationException(authenticationException.InnerException);
+                    }
+
+                    if (exception is OperationCanceledException)
+                    {
+                        throw new MqttCommunicationTimedOutException();
+                    }
+
+                    throw new MqttCommunicationException(exception);
+                }
+            }
+            catch (OperationCanceledException)
+            {
+                throw new MqttCommunicationTimedOutException();
+            }
+            finally
+            {
+                _webSocket.Opened -= SuccessHandler;
+                _webSocket.Error -= ErrorHandler;
+            }
+        }
+    }
+}

Source/MQTTnet.Extensions.WebSocket4Net/WebSocket4NetMqttClientAdapterFactory.cs

@@ -0,0 +1,36 @@
+using System;
+using MQTTnet.Adapter;
+using MQTTnet.Client.Options;
+using MQTTnet.Diagnostics;
+using MQTTnet.Formatter;
+using MQTTnet.Implementations;
+
+namespace MQTTnet.Extensions.WebSocket4Net
+{
+    public class WebSocket4NetMqttClientAdapterFactory : IMqttClientAdapterFactory
+    {
+        public IMqttChannelAdapter CreateClientAdapter(IMqttClientOptions options, IMqttNetChildLogger logger)
+        {
+            if (options == null) throw new ArgumentNullException(nameof(options));
+            if (logger == null) throw new ArgumentNullException(nameof(logger));
+
+            switch (options.ChannelOptions)
+            {
+                case MqttClientTcpOptions _:
+                {
+                    return new MqttChannelAdapter(new MqttTcpChannel(options), new MqttPacketFormatterAdapter(options.ProtocolVersion), logger);
+                }
+
+                case MqttClientWebSocketOptions webSocketOptions:
+                {
+                    return new MqttChannelAdapter(new WebSocket4NetMqttChannel(options, webSocketOptions), new MqttPacketFormatterAdapter(options.ProtocolVersion), logger);
+                }
+
+                default:
+                {
+                    throw new NotSupportedException();
+                }
+            }
+        }
+    }
+}

Source/MQTTnet/Client/IMqttClientFactory.cs

@@ -5,6 +5,8 @@ namespace MQTTnet.Client
 {
     public interface IMqttClientFactory
     {
+        IMqttFactory UseClientAdapterFactory(IMqttClientAdapterFactory clientAdapterFactory);
+
         IMqttClient CreateMqttClient();
 
         IMqttClient CreateMqttClient(IMqttNetLogger logger);

Source/MQTTnet/MqttFactory.cs

@@ -10,6 +10,8 @@ namespace MQTTnet
 {
     public class MqttFactory : IMqttFactory
     {
+        private IMqttClientAdapterFactory _clientAdapterFactory = new MqttClientAdapterFactory();
+
         public MqttFactory() : this(new MqttNetLogger())
         {
         }
@@ -21,6 +23,12 @@ namespace MQTTnet
 
         public IMqttNetLogger DefaultLogger { get; }
 
+        public IMqttFactory UseClientAdapterFactory(IMqttClientAdapterFactory clientAdapterFactory)
+        {
+            _clientAdapterFactory = clientAdapterFactory ?? throw new ArgumentNullException(nameof(clientAdapterFactory));
+            return this;
+        }
+
         public IMqttClient CreateMqttClient()
         {
             return CreateMqttClient(DefaultLogger);
@@ -30,22 +38,22 @@ namespace MQTTnet
         {
             if (logger == null) throw new ArgumentNullException(nameof(logger));
 
-            return new MqttClient(new MqttClientAdapterFactory(), logger);
+            return new MqttClient(_clientAdapterFactory, logger);
         }
 
-        public IMqttClient CreateMqttClient(IMqttClientAdapterFactory adapterFactory)
+        public IMqttClient CreateMqttClient(IMqttClientAdapterFactory clientAdapterFactory)
         {
-            if (adapterFactory == null) throw new ArgumentNullException(nameof(adapterFactory));
+            if (clientAdapterFactory == null) throw new ArgumentNullException(nameof(clientAdapterFactory));
 
-            return new MqttClient(adapterFactory, DefaultLogger);
+            return new MqttClient(clientAdapterFactory, DefaultLogger);
         }
 
-        public IMqttClient CreateMqttClient(IMqttNetLogger logger, IMqttClientAdapterFactory adapterFactory)
+        public IMqttClient CreateMqttClient(IMqttNetLogger logger, IMqttClientAdapterFactory clientAdapterFactory)
         {
             if (logger == null) throw new ArgumentNullException(nameof(logger));
-            if (adapterFactory == null) throw new ArgumentNullException(nameof(adapterFactory));
+            if (clientAdapterFactory == null) throw new ArgumentNullException(nameof(clientAdapterFactory));
 
-            return new MqttClient(adapterFactory, logger);
+            return new MqttClient(clientAdapterFactory, logger);
         }
 
         public IMqttServer CreateMqttServer()
@@ -60,19 +68,19 @@ namespace MQTTnet
             return CreateMqttServer(new List<IMqttServerAdapter> { new MqttTcpServerAdapter(logger.CreateChildLogger()) }, logger);
         }
 
-        public IMqttServer CreateMqttServer(IEnumerable<IMqttServerAdapter> adapters, IMqttNetLogger logger)
+        public IMqttServer CreateMqttServer(IEnumerable<IMqttServerAdapter> serverAdapters, IMqttNetLogger logger)
         {
-            if (adapters == null) throw new ArgumentNullException(nameof(adapters));
+            if (serverAdapters == null) throw new ArgumentNullException(nameof(serverAdapters));
             if (logger == null) throw new ArgumentNullException(nameof(logger));
 
-            return new MqttServer(adapters, logger.CreateChildLogger());
+            return new MqttServer(serverAdapters, logger.CreateChildLogger());
         }
 
-        public IMqttServer CreateMqttServer(IEnumerable<IMqttServerAdapter> adapters)
+        public IMqttServer CreateMqttServer(IEnumerable<IMqttServerAdapter> serverAdapters)
         {
-            if (adapters == null) throw new ArgumentNullException(nameof(adapters));
+            if (serverAdapters == null) throw new ArgumentNullException(nameof(serverAdapters));
             
-            return new MqttServer(adapters, DefaultLogger.CreateChildLogger());
+            return new MqttServer(serverAdapters, DefaultLogger.CreateChildLogger());
         }
     }
 }

Tests/MQTTnet.TestApp.NetCore/MQTTnet.TestApp.NetCore.csproj

@@ -17,6 +17,7 @@
 
   <ItemGroup>
     <ProjectReference Include="..\..\Source\MQTTnet.Extensions.ManagedClient\MQTTnet.Extensions.ManagedClient.csproj" />
+    <ProjectReference Include="..\..\Source\MQTTnet.Extensions.WebSocket4Net\MQTTnet.Extensions.WebSocket4Net.csproj" />
     <ProjectReference Include="..\..\Source\MQTTnet\MQTTnet.csproj" />
   </ItemGroup>
 

Tests/MQTTnet.TestApp.NetCore/PublicBrokerTest.cs

@@ -1,10 +1,13 @@
 using MQTTnet.Client;
 using System;
 using System.IO;
+using System.Net;
+using System.Security.Authentication;
 using System.Threading;
 using System.Threading.Tasks;
 using MQTTnet.Client.Options;
 using MQTTnet.Client.Receiving;
+using MQTTnet.Extensions.WebSocket4Net;
 using MQTTnet.Formatter;
 using MQTTnet.Protocol;
 using Newtonsoft.Json;
@@ -77,6 +80,7 @@ namespace MQTTnet.TestApp.NetCore
             {
                 Write("Testing '" + name + "'... ", ConsoleColor.Gray);
                 var factory = new MqttFactory();
+                //factory.UseWebSocket4Net();
                 var client = factory.CreateMqttClient();
                 var topic = Guid.NewGuid().ToString();
 

Tests/MQTTnet.TestApp.UniversalWindows/MQTTnet.TestApp.UniversalWindows.csproj

@@ -135,6 +135,10 @@
       <Project>{c444e9c8-95fa-430e-9126-274129de16cd}</Project>
       <Name>MQTTnet.Extensions.Rpc</Name>
     </ProjectReference>
+    <ProjectReference Include="..\..\Source\MQTTnet.Extensions.WebSocket4Net\MQTTnet.Extensions.WebSocket4Net.csproj">
+      <Project>{2BD01D53-4CA5-4142-BE8D-313876395E3E}</Project>
+      <Name>MQTTnet.Extensions.WebSocket4Net</Name>
+    </ProjectReference>
     <ProjectReference Include="..\..\Source\MQTTnet\MQTTnet.csproj">
       <Project>{3587e506-55a2-4eb3-99c7-dc01e42d25d2}</Project>
       <Name>MQTTnet</Name>

Tests/MQTTnet.TestApp.UniversalWindows/MainPage.xaml

@@ -63,6 +63,7 @@
                         <StackPanel Grid.Column="1" Grid.Row="6" Orientation="Horizontal">
                             <RadioButton x:Name="UseTcp" IsChecked="True" GroupName="transport">TCP</RadioButton>
                             <RadioButton x:Name="UseWs" GroupName="transport">WS</RadioButton>
+                            <RadioButton x:Name="UseWs4Net" GroupName="transport">WS (WebSocket4Net)</RadioButton>
                             <CheckBox x:Name="UseTls">Use TLS</CheckBox>
                         </StackPanel>
 

Tests/MQTTnet.TestApp.UniversalWindows/MainPage.xaml.cs

@@ -1,8 +1,6 @@
 using System;
 using System.Collections.Concurrent;
 using System.Collections.ObjectModel;
-using System.Net.Security;
-using System.Security.Cryptography.X509Certificates;
 using System.Text;
 using System.Threading.Tasks;
 using Windows.Security.Cryptography.Certificates;
@@ -23,6 +21,7 @@ using MQTTnet.Server;
 using MQTTnet.Server.Status;
 using MqttClientConnectedEventArgs = MQTTnet.Client.Connecting.MqttClientConnectedEventArgs;
 using MqttClientDisconnectedEventArgs = MQTTnet.Client.Disconnecting.MqttClientDisconnectedEventArgs;
+using MQTTnet.Extensions.WebSocket4Net;
 
 namespace MQTTnet.TestApp.UniversalWindows
 {
@@ -83,6 +82,8 @@ namespace MQTTnet.TestApp.UniversalWindows
 
         private async void Connect(object sender, RoutedEventArgs e)
         {
+            var mqttFactory = new MqttFactory();
+
             var tlsOptions = new MqttClientTlsOptions
             {
                 UseTls = UseTls.IsChecked == true,
@@ -116,6 +117,17 @@ namespace MQTTnet.TestApp.UniversalWindows
                 };
             }
 
+            if (UseWs4Net.IsChecked == true)
+            {
+                options.ChannelOptions = new MqttClientWebSocketOptions
+                {
+                    Uri = Server.Text,
+                    TlsOptions = tlsOptions
+                };
+
+                mqttFactory.UseWebSocket4Net();
+            }
+
             if (options.ChannelOptions == null)
             {
                 throw new InvalidOperationException();
@@ -156,11 +168,9 @@ namespace MQTTnet.TestApp.UniversalWindows
                     _mqttClient.DisconnectedHandler = new MqttClientDisconnectedHandlerDelegate(x => OnDisconnected(x));
                 }
 
-                var factory = new MqttFactory();
-
                 if (UseManagedClient.IsChecked == true)
                 {
-                    _managedMqttClient = factory.CreateManagedMqttClient();
+                    _managedMqttClient = mqttFactory.CreateManagedMqttClient();
                     _managedMqttClient.UseApplicationMessageReceivedHandler(HandleReceivedApplicationMessage);
                     _managedMqttClient.ConnectedHandler = new MqttClientConnectedHandlerDelegate(x => OnConnected(x));
                     _managedMqttClient.DisconnectedHandler = new MqttClientDisconnectedHandlerDelegate(x => OnDisconnected(x));
@@ -172,7 +182,7 @@ namespace MQTTnet.TestApp.UniversalWindows
                 }
                 else
                 {
-                    _mqttClient = factory.CreateMqttClient();
+                    _mqttClient = mqttFactory.CreateMqttClient();
                     _mqttClient.UseApplicationMessageReceivedHandler(HandleReceivedApplicationMessage);
                     _mqttClient.ConnectedHandler = new MqttClientConnectedHandlerDelegate(x => OnConnected(x));
                     _mqttClient.DisconnectedHandler = new MqttClientDisconnectedHandlerDelegate(x => OnDisconnected(x));
@@ -204,7 +214,7 @@ namespace MQTTnet.TestApp.UniversalWindows
 
         private async Task HandleReceivedApplicationMessage(MqttApplicationMessageReceivedEventArgs eventArgs)
         {
-            var item = $"Timestamp: {DateTime.Now:O} | Topic: {eventArgs.ApplicationMessage.Topic} | Payload: {Encoding.UTF8.GetString(eventArgs.ApplicationMessage.Payload)} | QoS: {eventArgs.ApplicationMessage.QualityOfServiceLevel}";
+            var item = $"Timestamp: {DateTime.Now:O} | Topic: {eventArgs.ApplicationMessage.Topic} | Payload: {eventArgs.ApplicationMessage.ConvertPayloadToString()} | QoS: {eventArgs.ApplicationMessage.QualityOfServiceLevel}";
 
             await Dispatcher.RunAsync(CoreDispatcherPriority.Low, () =>
             {
@@ -524,6 +534,13 @@ namespace MQTTnet.TestApp.UniversalWindows
                     Console.WriteLine();
                 });
 
+                void Handler(MqttApplicationMessageReceivedEventArgs args)
+                {
+                    //...
+                }
+                
+                client.UseApplicationMessageReceivedHandler(Handler);
+
                 // Subscribe after connect
 
                 client.UseConnectedHandler(async e =>