Merge branch 'develop'

Add UnitTests for RPC.
Merge branch 'master' into develop
2026-10-15 00:15:15 +08:00 · 2019-08-11 16:33:40 +02:00 · 2019-08-11 10:41:36 +02:00 · 2019-08-11 10:17:51 +02:00 · 2019-08-09 22:21:42 +02:00 · 2019-08-09 22:07:26 +02:00
175 changed files with 4022 additions and 748 deletions
@@ -0,0 +1,46 @@
+---
+name: Bug report
+about: Create a report to help us improve.
+title: ''
+labels: ''
+assignees: ''
+
+---
+
+### Describe the bug
+A clear and concise description of what the bug is.
+
+### Which project is your bug related to?
+<!-- Remove the items which don't apply from the following list -->
+- Client
+- ManagedClient
+- MQTTnet.Server standalone
+- Server
+- Generic
+
+### To Reproduce
+Steps to reproduce the behavior:
+1. Using this version of MQTTnet '...'.
+2. Run this code '....'.
+3. With these arguments '....'.
+4. See error.
+
+### Expected behavior
+A clear and concise description of what you expected to happen.
+
+### Screenshots
+If applicable, add screenshots to help explain your problem.
+
+### Additional context / logging
+Add any other context about the problem here.
+Include debugging or logging information here:
+
+```batch
+\\ Put your logging output here.
+```
+### Code example
+ Please provide full code examples below where possible to make it easier for the developers to check your issues.
+ 
+```csharp
+\\ Put your code here.
+```
@@ -0,0 +1,19 @@
+---
+name: Custom issue template
+about: Do you have a question related to the project? Use this template.
+title: ''
+labels: ''
+assignees: ''
+
+---
+
+### Describe your question
+A clear and concise description of what you want to know.
+
+### Which project is your question related to?
+<!-- Remove the items which don't apply from the following list -->
+- Client
+- ManagedClient
+- MQTTnet.Server standalone
+- Server
+- Generic
@@ -0,0 +1,29 @@
+---
+name: Feature request
+about: Suggest an idea for this project.
+title: ''
+labels: ''
+assignees: ''
+
+---
+
+### Describe the feature request
+Is your feature request related to a problem? Please describe.
+A clear and concise description of what the problem is. Example. I'm am trying to do [...] but [...]
+
+### Which project is your feature request related to?
+<!-- Remove the items which don't apply from the following list -->
+- Client
+- ManagedClient
+- MQTTnet.Server standalone
+- Server
+- Generic
+
+### Describe the solution you'd like
+A clear and concise description of what you want to happen.
+
+### Describe alternatives you've considered
+A clear and concise description of any alternative solutions or features you've considered.
+
+### Additional context
+Add any other context or screenshots about the feature request here.
@@ -292,3 +292,5 @@ __pycache__/
 *.map

 /Tests/MQTTnet.TestApp.NetCore/RetainedMessages.json
+
+Build/NuGet/
@@ -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>
@@ -9,7 +9,7 @@
    <projectUrl>https://github.com/chkr1011/MQTTnet</projectUrl>
    <iconUrl>https://raw.githubusercontent.com/chkr1011/MQTTnet/master/Images/Logo_128x128.png</iconUrl>
    <requireLicenseAcceptance>false</requireLicenseAcceptance>
-    <description>MQTTnet is a high performance .NET library for MQTT based communication. It provides a MQTT client and a MQTT server (broker). This package contains the .NET Standard version of the library only.</description>
+    <description>This package contains the .NET Standard version of MQTTnet only.</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> 
@@ -9,14 +9,18 @@
    <projectUrl>https://github.com/chkr1011/MQTTnet</projectUrl>
    <iconUrl>https://raw.githubusercontent.com/chkr1011/MQTTnet/master/Images/Logo_128x128.png</iconUrl>
    <requireLicenseAcceptance>false</requireLicenseAcceptance>
-    <description>MQTTnet is a high performance .NET library for MQTT based communication. It provides a MQTT client and a MQTT server (broker).</description>
+    <description>MQTTnet is a high performance .NET library for MQTT based communication. It provides a MQTT client and a MQTT server (broker) and supports v3.1.0, v3.1.1 and v5.0.0 of the MQTT protocol.</description>
    <releaseNotes>
-* [Core] Fixed missing properties from PUBLISH packet in _MqttApplicationMessage_ (thanks to @pcbing).
-* [Core] Fixed wrong encoding of PUBREL and PUBCOMP packets for MQTTv5 (thanks to @perphilipp).
-* [Client] Added the authentication result to the disconnected handler (only set when connecting failed).
-* [Client] Added new overloads for _MqttClientOptionsBuilder_.
-* [Server] Fixed a bug which returns wrong flag for existing session in CONNACK packet (thanks to @avengerstark).
-* [nuget] .NET Framework builds are now using 4.5.2 or 4.6.1 builds instead of netstandard 2.0.
+* [Core] Nuget packages with symbols are now also published to improve debugging.
+* [Core] Improve task handling (thanks to @mwinterb)
+* [ManagedClient] Fix a race condition in the message storage (thanks to @PaulFake).
+* [Server] Added items dictionary to client session in order to share data across interceptors as along as the session exists.
+* [Server] Exposed CONNECT packet properties in Application Message and Subscription interceptor.
+* [Server] Fixed: Sending Large packets with AspnetCore based connection throws System.ArgumentException.
+* [Server] Fixed wrong usage of socket option _NoDelay_.
+* [Server] Added remote certificate validation callback (thanks to @rudacs).
+* [Server] Add support for certificate passwords (thanks to @cslutgen).
+* [MQTTnet.Server] Added REST API for publishing basic messages.
    </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> 
@@ -36,17 +36,17 @@ 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 MQTTnet.Server
-Remove-Item ..\Source\MQTTnet.Server\bin\Release\netcoreapp2.2 -Recurse -Force -ErrorAction SilentlyContinue
-&$msbuild ..\Source\MQTTnet.Server\MQTTnet.Server.csproj /t:Build /p:Configuration="Release" /p:TargetFramework="netcoreapp2.2" /p:FileVersion=$assemblyVersion /p:AssemblyVersion=$assemblyVersion /verbosity:m /p:SignAssembly=true /p:AssemblyOriginatorKeyFile=".\..\..\Build\codeSigningKey.pfx"
-
-$source = "..\Source\MQTTnet.Server\bin\Release\netcoreapp2.2"
-$destination = "..\Source\MQTTnet.Server\bin\MQTTnet.Server-Portable-v$nugetVersion.zip"
-If(Test-path $destination) {Remove-item $destination}
- Add-Type -assembly "system.io.compression.filesystem"
-[io.compression.zipfile]::CreateFromDirectory($source, $destination) 
+# Build the WebSocket4Net extension
+&$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"

 # Create NuGet packages.
+
+Invoke-WebRequest -Uri "https://dist.nuget.org/win-x86-commandline/latest/nuget.exe" -OutFile "nuget.exe"
+
 Remove-Item .\NuGet -Force -Recurse -ErrorAction SilentlyContinue

 Copy-Item MQTTnet.AspNetCore.nuspec -Destination MQTTnet.AspNetCore.nuspec.old -Force
@@ -55,14 +55,66 @@ 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
-.\nuget.exe pack MQTTnet.NETStandard.nuspec -Verbosity detailed -Symbols -OutputDir "NuGet" -Version $nugetVersion
-.\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.nuspec -Verbosity detailed -Symbols -SymbolPackageFormat snupkg -OutputDir "NuGet" -Version $nugetVersion
+.\nuget.exe pack MQTTnet.NETStandard.nuspec -Verbosity detailed -Symbols -SymbolPackageFormat snupkg -OutputDir "NuGet" -Version $nugetVersion
+.\nuget.exe pack MQTTnet.AspNetCore.nuspec -Verbosity detailed -Symbols -SymbolPackageFormat snupkg -OutputDir "NuGet" -Version $nugetVersion
+.\nuget.exe pack MQTTnet.Extensions.Rpc.nuspec -Verbosity detailed -Symbols -SymbolPackageFormat snupkg -OutputDir "NuGet" -Version $nugetVersion
+.\nuget.exe pack MQTTnet.Extensions.ManagedClient.nuspec -Verbosity detailed -Symbols -SymbolPackageFormat snupkg -OutputDir "NuGet" -Version $nugetVersion
+.\nuget.exe pack MQTTnet.Extensions.WebSocket4Net.nuspec -Verbosity detailed -Symbols -SymbolPackageFormat snupkg -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
+
+Remove-Item "nuget.exe" -Force -Recurse -ErrorAction SilentlyContinue
+
+####################################################################
+
+# Build MQTTnet.Server Portable
+&dotnet publish ..\Source\MQTTnet.Server\MQTTnet.Server.csproj --configuration Release /p:FileVersion=$assemblyVersion /p:Version=$nugetVersion
+
+$source = "..\Source\MQTTnet.Server\bin\Release\netcoreapp2.2\publish"
+$destination = "..\Source\MQTTnet.Server\bin\MQTTnet.Server-Portable-v$nugetVersion.zip"
+If(Test-path $destination) {Remove-item $destination}
+ Add-Type -assembly "system.io.compression.filesystem"
+[io.compression.zipfile]::CreateFromDirectory($source, $destination) 
+
+####################################################################
+
+# Build MQTTnet.Server Linux-x64
+&dotnet publish ..\Source\MQTTnet.Server\MQTTnet.Server.csproj --configuration Release /p:FileVersion=$assemblyVersion /p:Version=$nugetVersion --self-contained --runtime linux-x64 
+
+$source = "..\Source\MQTTnet.Server\bin\Release\netcoreapp2.2\linux-x64\publish"
+$destination = "..\Source\MQTTnet.Server\bin\MQTTnet.Server-Linux-x64-v$nugetVersion.zip"
+If(Test-path $destination) {Remove-item $destination}
+ Add-Type -assembly "system.io.compression.filesystem"
+[io.compression.zipfile]::CreateFromDirectory($source, $destination) 
+
+####################################################################
+
+# Build MQTTnet.Server Linux-ARM
+&dotnet publish ..\Source\MQTTnet.Server\MQTTnet.Server.csproj --configuration Release /p:FileVersion=$assemblyVersion /p:Version=$nugetVersion --self-contained --runtime linux-arm 
+
+$source = "..\Source\MQTTnet.Server\bin\Release\netcoreapp2.2\linux-ARM\publish"
+$destination = "..\Source\MQTTnet.Server\bin\MQTTnet.Server-Linux-ARM-v$nugetVersion.zip"
+If(Test-path $destination) {Remove-item $destination}
+ Add-Type -assembly "system.io.compression.filesystem"
+[io.compression.zipfile]::CreateFromDirectory($source, $destination) 
+
+####################################################################
+
+# Build MQTTnet.Server Windows-x64
+&dotnet publish ..\Source\MQTTnet.Server\MQTTnet.Server.csproj --configuration Release /p:FileVersion=$assemblyVersion /p:Version=$nugetVersion --self-contained --runtime win-x64
+
+$source = "..\Source\MQTTnet.Server\bin\Release\netcoreapp2.2\win-x64\publish"
+$destination = "..\Source\MQTTnet.Server\bin\MQTTnet.Server-Windows-x64-v$nugetVersion.zip"
+If(Test-path $destination) {Remove-item $destination}
+ Add-Type -assembly "system.io.compression.filesystem"
+[io.compression.zipfile]::CreateFromDirectory($source, $destination) 
+
+####################################################################
@@ -1,9 +1,13 @@
 param([string]$apiKey)

+Invoke-WebRequest -Uri "https://dist.nuget.org/win-x86-commandline/latest/nuget.exe" -OutFile "nuget.exe"
+
 $files = Get-ChildItem -Path ".\NuGet" -Filter "*.nupkg"
 foreach ($file in $files)
 {
 	Write-Host "Uploading: " $file

-	.\nuget.exe push $file.Fullname $apiKey -NoSymbols -Source https://api.nuget.org/v3/index.json
-}
+	.\nuget.exe push $file.Fullname $apiKey -Source https://api.nuget.org/v3/index.json
+}
+
+Remove-Item "nuget.exe" -Force -Recurse -ErrorAction SilentlyContinue
@@ -0,0 +1,239 @@
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+<!-- Created with Inkscape (http://www.inkscape.org/) -->
+
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+       inkscape:export-xdpi="2.6500001"
+       inkscape:export-ydpi="2.6500001" />
+    <text
+       xml:space="preserve"
+       style="font-style:normal;font-weight:normal;font-size:10.58333302px;line-height:1.25;font-family:sans-serif;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;stroke-width:0.26458332"
+       x="102.34985"
+       y="320.75201"
+       id="text3774"
+       inkscape:export-xdpi="2.6500001"
+       inkscape:export-ydpi="2.6500001"><tspan
+         sodipodi:role="line"
+         id="tspan3772"
+         x="102.34985"
+         y="320.75201"
+         style="font-size:141.1111145px;fill:#ffffff;stroke-width:0.26458332">MQTT</tspan></text>
+    <ellipse
+       ry="33.94323"
+       rx="39.021355"
+       cy="148.56271"
+       cx="124.47787"
+       id="ellipse3768"
+       style="fill:#d40000;stroke-width:0.06901014"
+       inkscape:export-xdpi="2.6500001"
+       inkscape:export-ydpi="2.6500001" />
+    <ellipse
+       style="fill:#d40000;stroke-width:0.06901014"
+       id="ellipse3770"
+       cx="234.9953"
+       cy="556.91571"
+       rx="39.021355"
+       ry="33.94323"
+       inkscape:export-xdpi="2.6500001"
+       inkscape:export-ydpi="2.6500001" />
+    <text
+       id="text3778"
+       y="474.73837"
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+       style="font-style:normal;font-weight:normal;font-size:10.58333302px;line-height:1.25;font-family:sans-serif;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;stroke-width:0.26458332"
+       xml:space="preserve"
+       inkscape:export-xdpi="2.6500001"
+       inkscape:export-ydpi="2.6500001"><tspan
+         style="font-size:141.1111145px;fill:#ffffff;stroke-width:0.26458332"
+         y="474.73837"
+         x="194.57605"
+         id="tspan3776"
+         sodipodi:role="line">net</tspan></text>
+    <rect
+       ry="50"
+       rx="50"
+       style="fill:#aa0000;stroke-width:0.26458332"
+       y="97.349655"
+       x="-672.18286"
+       height="512"
+       width="512"
+       id="rect4642"
+       inkscape:export-xdpi="6.3499999"
+       inkscape:export-ydpi="6.3499999" />
+    <path
+       inkscape:connector-curvature="0"
+       id="path4648"
+       d="m -160.18302,381.97945 a 263.46279,229.17652 0 0 0 -222.88457,226.0446 263.46279,229.17652 0 0 0 0.0791,1.32549 h 172.80546 c 27.70002,0 50.00005,-22.30004 50.00005,-50.00004 z"
+       style="fill:#d40000;stroke-width:0.46593982"
+       inkscape:export-xdpi="6.3499999"
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+       xml:space="preserve"
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+         style="font-weight:bold;font-size:141.1111145px;fill:#ffffff;stroke-width:0.26458332"
+         y="329.30466"
+         x="-639.42944"
+         id="tspan4654"
+         sodipodi:role="line">MQTT</tspan></text>
+    <text
+       xml:space="preserve"
+       style="font-style:normal;font-weight:normal;font-size:10.58333302px;line-height:1.25;font-family:sans-serif;letter-spacing:0px;word-spacing:0px;fill:#000000;fill-opacity:1;stroke:none;stroke-width:0.26458332"
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+         style="font-weight:bold;font-size:141.1111145px;fill:#ffffff;stroke-width:0.26458332">net</tspan></text>
+  </g>
+</svg>
@@ -47,6 +47,8 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "MQTTnet.Tests", "Tests\MQTT
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "MQTTnet.Server", "Source\MQTTnet.Server\MQTTnet.Server.csproj", "{DADEA836-5CC3-474C-A2D8-4D0F31118CD7}"
 EndProject
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "MQTTnet.Extensions.WebSocket4Net", "Source\MQTTnet.Extensions.WebSocket4Net\MQTTnet.Extensions.WebSocket4Net.csproj", "{9AE2F8DA-4178-470B-B8C4-88BE1DAE7D5F}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -219,6 +221,22 @@ Global
 		{DADEA836-5CC3-474C-A2D8-4D0F31118CD7}.Release|x64.Build.0 = Release|Any CPU
 		{DADEA836-5CC3-474C-A2D8-4D0F31118CD7}.Release|x86.ActiveCfg = Release|Any CPU
 		{DADEA836-5CC3-474C-A2D8-4D0F31118CD7}.Release|x86.Build.0 = Release|Any CPU
+		{9AE2F8DA-4178-470B-B8C4-88BE1DAE7D5F}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{9AE2F8DA-4178-470B-B8C4-88BE1DAE7D5F}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{9AE2F8DA-4178-470B-B8C4-88BE1DAE7D5F}.Debug|ARM.ActiveCfg = Debug|Any CPU
+		{9AE2F8DA-4178-470B-B8C4-88BE1DAE7D5F}.Debug|ARM.Build.0 = Debug|Any CPU
+		{9AE2F8DA-4178-470B-B8C4-88BE1DAE7D5F}.Debug|x64.ActiveCfg = Debug|Any CPU
+		{9AE2F8DA-4178-470B-B8C4-88BE1DAE7D5F}.Debug|x64.Build.0 = Debug|Any CPU
+		{9AE2F8DA-4178-470B-B8C4-88BE1DAE7D5F}.Debug|x86.ActiveCfg = Debug|Any CPU
+		{9AE2F8DA-4178-470B-B8C4-88BE1DAE7D5F}.Debug|x86.Build.0 = Debug|Any CPU
+		{9AE2F8DA-4178-470B-B8C4-88BE1DAE7D5F}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{9AE2F8DA-4178-470B-B8C4-88BE1DAE7D5F}.Release|Any CPU.Build.0 = Release|Any CPU
+		{9AE2F8DA-4178-470B-B8C4-88BE1DAE7D5F}.Release|ARM.ActiveCfg = Release|Any CPU
+		{9AE2F8DA-4178-470B-B8C4-88BE1DAE7D5F}.Release|ARM.Build.0 = Release|Any CPU
+		{9AE2F8DA-4178-470B-B8C4-88BE1DAE7D5F}.Release|x64.ActiveCfg = Release|Any CPU
+		{9AE2F8DA-4178-470B-B8C4-88BE1DAE7D5F}.Release|x64.Build.0 = Release|Any CPU
+		{9AE2F8DA-4178-470B-B8C4-88BE1DAE7D5F}.Release|x86.ActiveCfg = Release|Any CPU
+		{9AE2F8DA-4178-470B-B8C4-88BE1DAE7D5F}.Release|x86.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
@@ -234,6 +252,7 @@ Global
 		{61B62223-F5D0-48E4-BBD6-2CBA9353CB5E} = {9248C2E1-B9D6-40BF-81EC-86004D7765B4}
 		{9C7106CA-96B8-4ABE-B3B4-9357AB8ACB41} = {9248C2E1-B9D6-40BF-81EC-86004D7765B4}
 		{DADEA836-5CC3-474C-A2D8-4D0F31118CD7} = {32A630A7-2598-41D7-B625-204CD906F5FB}
+		{9AE2F8DA-4178-470B-B8C4-88BE1DAE7D5F} = {12816BCC-AF9E-44A9-9AE5-C246AF2A0587}
 	EndGlobalSection
 	GlobalSection(ExtensibilityGlobals) = postSolution
 		SolutionGuid = {07536672-5CBC-4BE3-ACE0-708A431A7894}
@@ -1,7 +1,7 @@

 Microsoft Visual Studio Solution File, Format Version 12.00
 # Visual Studio Version 16
-VisualStudioVersion = 16.0.28729.10
+VisualStudioVersion = 16.0.29009.5
 MinimumVisualStudioVersion = 10.0.40219.1
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "MQTTnet.Tests", "Tests\MQTTnet.Core.Tests\MQTTnet.Tests.csproj", "{A7FF0C91-25DE-4BA6-B39E-F54E8DADF1CC}"
 EndProject
@@ -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}
@@ -1,5 +1,5 @@
 <p align="center">
-<img src="https://github.com/chkr1011/MQTTnet/blob/master/Images/Logo_128x128.png?raw=true" width="128">
+<img src="https://github.com/chkr1011/MQTTnet/blob/master/Images/icon_det_256.png?raw=true" width="196">
 <br/>
 <br/>
 </p>
@@ -8,7 +8,8 @@
 [![Build status](https://ci.appveyor.com/api/projects/status/ycit86voxfevm2aa/branch/master?svg=true)](https://ci.appveyor.com/project/chkr1011/mqttnet)
 [![BCH compliance](https://bettercodehub.com/edge/badge/chkr1011/MQTTnet?branch=master)](https://bettercodehub.com/)
 [![OpenCollective](https://opencollective.com/mqttnet/backers/badge.svg)](https://opencollective.com/mqttnet) 
-[![OpenCollective](https://opencollective.com/mqttnet/sponsors/badge.svg)](https://opencollective.com/mqttnet)
+[![OpenCollective](https://opencollective.com/mqttnet/sponsors/badge.svg)](https://opencollective.com/mqttnet) [![Join the chat at https://gitter.im/MQTTnet/community](https://badges.gitter.im/MQTTnet/community.svg)](https://gitter.im/MQTTnet/community?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
+[![License: MIT](https://img.shields.io/badge/License-MIT-yellow.svg)](https://raw.githubusercontent.com/chkr1011/MQTTnet/master/LICENSE)

 # MQTTnet

@@ -26,7 +27,7 @@ MQTTnet is a high performance .NET library for MQTT based communication. It prov
 * Uniform API across all supported versions of the MQTT protocol
 * Interfaces included for mocking and testing
 * Access to internal trace messages
-* Unit tested (~200 tests)
+* Unit tested (~210 tests)
 * No external dependencies

 \* Tested on local machine (Intel i7 8700K) with MQTTnet client and server running in the same process using the TCP channel. The app for verification is part of this repository and stored in _/Tests/MQTTnet.TestApp.NetCore_.
@@ -104,6 +105,8 @@ This library is used in the following projects:
 * MQTT Tester (MQTT client test app for [Android](https://play.google.com/store/apps/details?id=com.liveowl.mqtttester) and [iOS](https://itunes.apple.com/us/app/mqtt-tester/id1278621826?mt=8))
 * Wirehome.Core (Open Source Home Automation system for .NET Core, <https://github.com/chkr1011/Wirehome.Core>)

+Further projects using this project can be found under https://github.com/chkr1011/MQTTnet/network/dependents.
+
 If you use this library and want to see your project here please create a pull request.

 ## License
@@ -7,6 +7,7 @@ using MQTTnet.Formatter;
 using MQTTnet.Packets;
 using System;
 using System.IO.Pipelines;
+using System.Security.Cryptography.X509Certificates;
 using System.Threading;
 using System.Threading.Tasks;

@@ -48,6 +49,8 @@ namespace MQTTnet.AspNetCore

        public bool IsSecureConnection => Http?.HttpContext?.Request?.IsHttps ?? false;

+        public X509Certificate2 ClientCertificate => Http?.HttpContext?.Connection?.ClientCertificate;
+
        private IHttpContextFeature Http => Connection.Features.Get<IHttpContextFeature>();

        public ConnectionContext Connection { get; }
@@ -142,6 +145,12 @@ namespace MQTTnet.AspNetCore
            return null;
        }

+        public void ResetStatistics()
+        {
+            BytesReceived = 0;
+            BytesSent = 0;
+        }
+
        public async Task SendPacketAsync(MqttBasePacket packet, TimeSpan timeout, CancellationToken cancellationToken)
        {
            var formatter = PacketFormatterAdapter;
@@ -153,11 +162,12 @@ namespace MQTTnet.AspNetCore
                var buffer = formatter.Encode(packet);
                var msg = buffer.AsMemory();
                var output = _output;
-                msg.CopyTo(output.GetMemory(msg.Length));
-                BytesSent += msg.Length;
+                var result = await output.WriteAsync(msg, cancellationToken).ConfigureAwait(false);
+                if (result.IsCompleted)
+                {
+                    BytesSent += msg.Length;
+                }
                PacketFormatterAdapter.FreeBuffer();
-                output.Advance(msg.Length);
-                await output.FlushAsync().ConfigureAwait(false);
            }
            finally
            {
@@ -40,19 +40,26 @@ namespace MQTTnet.AspNetCore
            var endpoint = $"{httpContext.Connection.RemoteIpAddress}:{httpContext.Connection.RemotePort}";
            
            var clientCertificate = await httpContext.Connection.GetClientCertificateAsync().ConfigureAwait(false);
-            var isSecureConnection = clientCertificate != null;
-            clientCertificate?.Dispose();
-
-            var clientHandler = ClientHandler;
-            if (clientHandler != null)
+            try
            {
-                var writer = new SpanBasedMqttPacketWriter();
-                var formatter = new MqttPacketFormatterAdapter(writer);
-                var channel = new MqttWebSocketChannel(webSocket, endpoint, isSecureConnection);
-                using (var channelAdapter = new MqttChannelAdapter(channel, formatter, _logger.CreateChildLogger(nameof(MqttWebSocketServerAdapter))))
+                var isSecureConnection = clientCertificate != null;
+
+                var clientHandler = ClientHandler;
+                if (clientHandler != null)
                {
-                    await clientHandler(channelAdapter).ConfigureAwait(false);
-                }   
+                    var writer = new SpanBasedMqttPacketWriter();
+                    var formatter = new MqttPacketFormatterAdapter(writer);
+                    var channel = new MqttWebSocketChannel(webSocket, endpoint, isSecureConnection, clientCertificate);
+
+                    using (var channelAdapter = new MqttChannelAdapter(channel, formatter, _logger.CreateChildLogger(nameof(MqttWebSocketServerAdapter))))
+                    {
+                        await clientHandler(channelAdapter).ConfigureAwait(false);
+                    }
+                }
+            }
+            finally
+            {
+                clientCertificate?.Dispose();
            }
        }

@@ -9,6 +9,7 @@ namespace MQTTnet.AspNetCore
    public class SpanBasedMqttPacketBodyReader : IMqttPacketBodyReader
    {
        private ReadOnlyMemory<byte> _buffer;
+
        private int _offset;
        
        public void SetBuffer(ReadOnlyMemory<byte> buffer)
@@ -17,11 +18,11 @@ namespace MQTTnet.AspNetCore
            _offset = 0;
        }

-        public ulong Length => (ulong)_buffer.Length;
+        public int Length => _buffer.Length;

        public bool EndOfStream => _buffer.Length.Equals(_offset);
        
-        public ulong Offset => (ulong)_offset;
+        public int Offset => _offset;

        public byte ReadByte()
        {
@@ -116,9 +117,9 @@ namespace MQTTnet.AspNetCore
            throw new MqttProtocolViolationException("Boolean values can be 0 or 1 only.");
        }

-        public void Seek(ulong position)
+        public void Seek(int position)
        {
-            _offset = (int)position;
+            _offset = position;
        }
    }
 }
@@ -3,7 +3,7 @@
  <PropertyGroup>
    <TargetFrameworks>netstandard1.3;netstandard2.0</TargetFrameworks>
    <TargetFrameworks Condition=" '$(OS)' == 'Windows_NT' ">$(TargetFrameworks);net452;net461</TargetFrameworks>
-    <TargetFrameworks Condition=" '$(OS)' == 'Windows_NT' AND '$(MSBuildRuntimeType)' != 'Core'">$(TargetFrameworks);uap10.0</TargetFrameworks>
+    <TargetFrameworks Condition=" '$(OS)' == 'Windows_NT' AND '$(MSBuildRuntimeType)' != 'Core' AND '$(SolutionName)' != 'MQTTnet.noUWP' ">$(TargetFrameworks);uap10.0</TargetFrameworks>
    <Product />
    <Company />
    <Authors />
@@ -24,6 +24,8 @@ namespace MQTTnet.Extensions.ManagedClient

        private readonly IMqttClient _mqttClient;
        private readonly IMqttNetChildLogger _logger;
+        
+        private readonly AsyncLock _messageQueueLock = new AsyncLock();

        private CancellationTokenSource _connectionCancellationToken;
        private CancellationTokenSource _publishingCancellationToken;
@@ -31,7 +33,7 @@ namespace MQTTnet.Extensions.ManagedClient

        private ManagedMqttClientStorageManager _storageManager;

-        private bool _disposed = false;
+        private bool _disposed;
        private bool _subscriptionsNotPushed;

        public ManagedMqttClient(IMqttClient mqttClient, IMqttNetChildLogger logger)
@@ -102,9 +104,8 @@ namespace MQTTnet.Extensions.ManagedClient

            _connectionCancellationToken = new CancellationTokenSource();

-#pragma warning disable CS4014 // Because this call is not awaited, execution of the current method continues before the call is completed
            _maintainConnectionTask = Task.Run(() => MaintainConnectionAsync(_connectionCancellationToken.Token), _connectionCancellationToken.Token);
-#pragma warning restore CS4014 // Because this call is not awaited, execution of the current method continues before the call is completed
+            _maintainConnectionTask.Forget(_logger);

            _logger.Info("Started");
        }
@@ -148,7 +149,7 @@ namespace MQTTnet.Extensions.ManagedClient

            try
            {
-                lock (_messageQueue)
+                using (await _messageQueueLock.WaitAsync(CancellationToken.None).ConfigureAwait(false))
                {
                    if (_messageQueue.Count >= Options.MaxPendingMessages)
                    {
@@ -168,6 +169,16 @@ namespace MQTTnet.Extensions.ManagedClient
                    }

                    _messageQueue.Enqueue(applicationMessage);
+                    
+                    if (_storageManager != null)
+                    {
+                        if (removedMessage != null)
+                        {
+                            await _storageManager.RemoveAsync(removedMessage).ConfigureAwait(false);
+                        }
+
+                        await _storageManager.AddAsync(applicationMessage).ConfigureAwait(false);
+                    }
                }
            }
            finally
@@ -182,16 +193,6 @@ namespace MQTTnet.Extensions.ManagedClient
                }

            }
-            
-            if (_storageManager != null)
-            {
-                if (removedMessage != null)
-                {
-                    await _storageManager.RemoveAsync(removedMessage).ConfigureAwait(false);
-                }
-
-                await _storageManager.AddAsync(applicationMessage).ConfigureAwait(false);
-            }
        }

        public Task SubscribeAsync(IEnumerable<TopicFilter> topicFilters)
@@ -333,20 +334,20 @@ namespace MQTTnet.Extensions.ManagedClient
            }
        }

-        private void PublishQueuedMessages(CancellationToken cancellationToken)
+        private async Task PublishQueuedMessagesAsync(CancellationToken cancellationToken)
        {
            try
            {
                while (!cancellationToken.IsCancellationRequested && _mqttClient.IsConnected)
                {
-                    //Peek at the message without dequeueing in order to prevent the
-                    //possibility of the queue growing beyond the configured cap.
-                    //Previously, messages could be re-enqueued if there was an
-                    //exception, and this re-enqueueing did not honor the cap.
-                    //Furthermore, because re-enqueueing would shuffle the order
-                    //of the messages, the DropOldestQueuedMessage strategy would
-                    //be unable to know which message is actually the oldest and would
-                    //instead drop the first item in the queue.
+                    // Peek at the message without dequeueing in order to prevent the
+                    // possibility of the queue growing beyond the configured cap.
+                    // Previously, messages could be re-enqueued if there was an
+                    // exception, and this re-enqueueing did not honor the cap.
+                    // Furthermore, because re-enqueueing would shuffle the order
+                    // of the messages, the DropOldestQueuedMessage strategy would
+                    // be unable to know which message is actually the oldest and would
+                    // instead drop the first item in the queue.
                    var message = _messageQueue.PeekAndWait();
                    if (message == null)
                    {
@@ -355,7 +356,7 @@ namespace MQTTnet.Extensions.ManagedClient

                    cancellationToken.ThrowIfCancellationRequested();

-                    TryPublishQueuedMessage(message);
+                    await TryPublishQueuedMessageAsync(message).ConfigureAwait(false);
                }
            }
            catch (OperationCanceledException)
@@ -363,7 +364,7 @@ namespace MQTTnet.Extensions.ManagedClient
            }
            catch (Exception exception)
            {
-                _logger.Error(exception, "Unhandled exception while publishing queued application messages.");
+                _logger.Error(exception, "Error while publishing queued application messages.");
            }
            finally
            {
@@ -371,23 +372,28 @@ namespace MQTTnet.Extensions.ManagedClient
            }
        }

-        private void TryPublishQueuedMessage(ManagedMqttApplicationMessage message)
+        private async Task TryPublishQueuedMessageAsync(ManagedMqttApplicationMessage message)
        {
            Exception transmitException = null;
            try
            {
-                _mqttClient.PublishAsync(message.ApplicationMessage).GetAwaiter().GetResult();
-                lock (_messageQueue) //lock to avoid conflict with this.PublishAsync
+                await _mqttClient.PublishAsync(message.ApplicationMessage).ConfigureAwait(false);
+
+                using (await _messageQueueLock.WaitAsync(CancellationToken.None).ConfigureAwait(false)) //lock to avoid conflict with this.PublishAsync
                {
-                    //While publishing this message, this.PublishAsync could have booted this
-                    //message off the queue to make room for another (when using a cap
-                    //with the DropOldestQueuedMessage strategy).  If the first item
-                    //in the queue is equal to this message, then it's safe to remove
-                    //it from the queue.  If not, that means this.PublishAsync has already
-                    //removed it, in which case we don't want to do anything.
+                    // While publishing this message, this.PublishAsync could have booted this
+                    // message off the queue to make room for another (when using a cap
+                    // with the DropOldestQueuedMessage strategy).  If the first item
+                    // in the queue is equal to this message, then it's safe to remove
+                    // it from the queue.  If not, that means this.PublishAsync has already
+                    // removed it, in which case we don't want to do anything.
                    _messageQueue.RemoveFirst(i => i.Id.Equals(message.Id));
+                    
+                    if (_storageManager != null)
+                    {
+                        await _storageManager.RemoveAsync(message).ConfigureAwait(false);
+                    }
                }
-                _storageManager?.RemoveAsync(message).GetAwaiter().GetResult();
            }
            catch (MqttCommunicationException exception)
            {
@@ -404,20 +410,30 @@ namespace MQTTnet.Extensions.ManagedClient
                    //contradict the expected behavior of QoS 1 and 2, that's also true
                    //for the usage of a message queue cap, so it's still consistent
                    //with prior behavior in that way.
-                    lock (_messageQueue) //lock to avoid conflict with this.PublishAsync
+                    using (await _messageQueueLock.WaitAsync(CancellationToken.None).ConfigureAwait(false)) //lock to avoid conflict with this.PublishAsync
                    {
                        _messageQueue.RemoveFirst(i => i.Id.Equals(message.Id));
+                        
+                        if (_storageManager != null)
+                        {
+                            await _storageManager.RemoveAsync(message).ConfigureAwait(false);
+                        }
                    }
                }
            }
            catch (Exception exception)
            {
                transmitException = exception;
-                _logger.Error(exception, $"Unhandled exception while publishing application message ({message.Id}).");
+                _logger.Error(exception, $"Error while publishing application message ({message.Id}).");
            }
            finally
            {
-                ApplicationMessageProcessedHandler?.HandleApplicationMessageProcessedAsync(new ApplicationMessageProcessedEventArgs(message, transmitException)).GetAwaiter().GetResult();
+                var eventHandler = ApplicationMessageProcessedHandler;
+                if (eventHandler != null)
+                {
+                    var eventArguments = new ApplicationMessageProcessedEventArgs(message, transmitException);
+                    await eventHandler.HandleApplicationMessageProcessedAsync(eventArguments).ConfigureAwait(false);
+                }
            }
        }

@@ -502,7 +518,7 @@ namespace MQTTnet.Extensions.ManagedClient
            var cts = new CancellationTokenSource();
            _publishingCancellationToken = cts;

-            Task.Factory.StartNew(() => PublishQueuedMessages(cts.Token), cts.Token, TaskCreationOptions.LongRunning, TaskScheduler.Default);
+            Task.Run(() => PublishQueuedMessagesAsync(cts.Token), cts.Token).Forget(_logger);
        }

        private void StopPublishing()
@@ -519,4 +535,4 @@ namespace MQTTnet.Extensions.ManagedClient
            _connectionCancellationToken = null;
        }
    }
-}
+}
@@ -3,7 +3,7 @@
  <PropertyGroup>
    <TargetFrameworks>netstandard1.3;netstandard2.0</TargetFrameworks>
    <TargetFrameworks Condition=" '$(OS)' == 'Windows_NT' ">$(TargetFrameworks);net452;net461</TargetFrameworks>
-    <TargetFrameworks Condition=" '$(OS)' == 'Windows_NT' AND '$(MSBuildRuntimeType)' != 'Core'">$(TargetFrameworks);uap10.0</TargetFrameworks>
+    <TargetFrameworks Condition=" '$(OS)' == 'Windows_NT' AND '$(MSBuildRuntimeType)' != 'Core' AND '$(SolutionName)' != 'MQTTnet.noUWP' ">$(TargetFrameworks);uap10.0</TargetFrameworks>
    <Product />
    <Company />
    <Authors />
@@ -0,0 +1,34 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFrameworks>netstandard1.3;netstandard2.0</TargetFrameworks>
+    <TargetFrameworks Condition=" '$(OS)' == 'Windows_NT' ">$(TargetFrameworks);net452;net461</TargetFrameworks>
+    <TargetFrameworks Condition=" '$(OS)' == 'Windows_NT' AND '$(MSBuildRuntimeType)' != 'Core' AND '$(SolutionName)' != 'MQTTnet.noUWP' ">$(TargetFrameworks);uap10.0</TargetFrameworks>
+    <Product />
+    <Company />
+    <Authors />
+    <PackageId />
+  </PropertyGroup>
+
+  <PropertyGroup Condition="'$(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>
@@ -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());
+        }
+    }
+}
@@ -0,0 +1,233 @@
+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 X509Certificate2 ClientCertificate { get; }
+
+        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;
+            }
+        }
+    }
+}
@@ -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();
+                }
+            }
+        }
+    }
+}
@@ -1,9 +1,9 @@
 namespace MQTTnet.Server.Configuration
 {
    /// <summary>
-    /// Main Settings Model
+    /// MQTT settings Model
    /// </summary>
-    public class SettingsModel
+    public class MqttSettingsModel
    {
        /// <summary>
        /// Set default connection timeout in seconds
@@ -0,0 +1,24 @@
+using System;
+using System.IO;
+
+namespace MQTTnet.Server.Configuration
+{
+    public static class PathHelper
+    {
+        public static string ExpandPath(string path)
+        {
+            if (path == null)
+            {
+                return null;
+            }
+
+            var uri = new Uri(path, UriKind.RelativeOrAbsolute);
+            if (!uri.IsAbsoluteUri)
+            {
+                return Path.Combine(AppDomain.CurrentDomain.BaseDirectory, path);
+            }
+
+            return path;
+        }
+    }
+}
@@ -6,6 +6,6 @@

        public int WriteInterval { get; set; } = 10;

-        public string Filename { get; set; } = "RetainedApplicationMessages.json";
+        public string Path { get; set; }
    }
 }
@@ -0,0 +1,11 @@
+using System.Collections.Generic;
+
+namespace MQTTnet.Server.Configuration
+{
+    public class ScriptingSettingsModel
+    {
+        public string ScriptsPath { get; set; }
+
+        public List<string> IncludePaths { get; set; }
+    }
+}
@@ -4,14 +4,16 @@ using System.Linq;
 using System.Net;
 using System.Threading.Tasks;
 using System.Web;
+using Microsoft.AspNetCore.Authorization;
 using Microsoft.AspNetCore.Mvc;
 using MQTTnet.Server.Mqtt;
 using MQTTnet.Server.Status;

 namespace MQTTnet.Server.Controllers
 {
+    [Authorize]
    [ApiController]
-    public class ClientsController : ControllerBase
+    public class ClientsController : Controller
    {
        private readonly MqttServerService _mqttServerService;

@@ -57,5 +59,21 @@ namespace MQTTnet.Server.Controllers
            await client.DisconnectAsync();
            return StatusCode((int)HttpStatusCode.NoContent);
        }
+
+        [Route("api/v1/clients/{clientId}/statistics")]
+        [HttpDelete]
+        public async Task<ActionResult> DeleteClientStatistics(string clientId)
+        {
+            clientId = HttpUtility.UrlDecode(clientId);
+
+            var client = (await _mqttServerService.GetClientStatusAsync()).FirstOrDefault(c => c.ClientId == clientId);
+            if (client == null)
+            {
+                return new StatusCodeResult((int)HttpStatusCode.NotFound);
+            }
+
+            client.ResetStatistics();
+            return StatusCode((int)HttpStatusCode.NoContent);
+        }
    }
 }
@@ -0,0 +1,51 @@
+using System;
+using System.IO;
+using System.Threading.Tasks;
+using Microsoft.AspNetCore.Authorization;
+using Microsoft.AspNetCore.Mvc;
+using MQTTnet.Protocol;
+using MQTTnet.Server.Mqtt;
+
+namespace MQTTnet.Server.Controllers
+{
+    [Authorize]
+    [ApiController]
+    public class MessagesController : Controller
+    {
+        private readonly MqttServerService _mqttServerService;
+
+        public MessagesController(MqttServerService mqttServerService)
+        {
+            _mqttServerService = mqttServerService ?? throw new ArgumentNullException(nameof(mqttServerService));
+        }
+
+        [Route("api/v1/messages")]
+        [HttpPost]
+        public async Task<ActionResult> PostMessage(MqttApplicationMessage message)
+        {
+            await _mqttServerService.PublishAsync(message);
+            return Ok();
+        }
+
+        [Route("api/v1/messages/{*topic}")]
+        [HttpPost]
+        public async Task<ActionResult> PostMessage(string topic, int qosLevel = 0)
+        {
+            byte[] payload;
+
+            using (var memoryStream = new MemoryStream())
+            {
+                await HttpContext.Request.Body.CopyToAsync(memoryStream);
+                payload = memoryStream.ToArray();
+            }
+
+            var message = new MqttApplicationMessageBuilder()
+                .WithTopic(topic)
+                .WithPayload(payload)
+                .WithQualityOfServiceLevel((MqttQualityOfServiceLevel)qosLevel)
+                .Build();
+
+            return await PostMessage(message);
+        }
+    }
+}
@@ -4,13 +4,15 @@ using System.Linq;
 using System.Net;
 using System.Threading.Tasks;
 using System.Web;
+using Microsoft.AspNetCore.Authorization;
 using Microsoft.AspNetCore.Mvc;
 using MQTTnet.Server.Mqtt;

 namespace MQTTnet.Server.Controllers
 {
+    [Authorize]
    [ApiController]
-    public class RetainedApplicationMessagesController : ControllerBase
+    public class RetainedApplicationMessagesController : Controller
    {
        private readonly MqttServerService _mqttServerService;

@@ -1,11 +1,65 @@
 using System;
 using System.Collections.Generic;
-using System.Linq;
+using System.Threading;
 using System.Threading.Tasks;
+using Microsoft.AspNetCore.Authorization;
+using Microsoft.AspNetCore.Mvc;
+using MQTTnet.Server.Scripting;
+using MQTTnet.Server.Web;

 namespace MQTTnet.Server.Controllers
 {
-    public class ScriptsController
+    [Authorize]
+    [ApiController]
+    public class ScriptsController : Controller
    {
+        private readonly PythonScriptHostService _pythonScriptHostService;
+
+        public ScriptsController(PythonScriptHostService pythonScriptHostService)
+        {
+            _pythonScriptHostService = pythonScriptHostService ?? throw new ArgumentNullException(nameof(pythonScriptHostService));
+        }
+
+        [Route("api/v1/scripts")]
+        [HttpGet]
+        public ActionResult<List<string>> GetScriptUids()
+        {
+            return _pythonScriptHostService.GetScriptUids();
+        }
+
+        [Route("api/v1/scripts/uid")]
+        [HttpGet]
+        public async Task<ActionResult<string>> GetScript(string uid)
+        {
+            var script = await _pythonScriptHostService.ReadScriptAsync(uid, HttpContext.RequestAborted);
+            if (script == null)
+            {
+                return NotFound();
+            }
+
+            return Content(script);
+        }
+
+        [Route("api/v1/scripts/uid")]
+        [HttpPost]
+        public Task PostScript(string uid)
+        {
+            var code = HttpContext.Request.ReadBodyAsString();
+            return _pythonScriptHostService.WriteScriptAsync(uid, code, CancellationToken.None);
+        }
+
+        [Route("api/v1/scripts/uid")]
+        [HttpDelete]
+        public Task DeleteScript(string uid)
+        {
+            return _pythonScriptHostService.DeleteScriptAsync(uid);
+        }
+        
+        [Route("api/v1/scripts/initialize")]
+        [HttpPost]
+        public Task PostInitializeScripts()
+        {
+            return _pythonScriptHostService.TryInitializeScriptsAsync();
+        }
    }
 }
@@ -0,0 +1,18 @@
+using Microsoft.AspNetCore.Authorization;
+using Microsoft.AspNetCore.Mvc;
+using System.Reflection;
+
+namespace MQTTnet.Server.Controllers
+{
+    [Authorize]
+    [ApiController]
+    public class ServerController : Controller
+    {
+        [Route("api/v1/server/version")]
+        [HttpGet]
+        public ActionResult<string> GetVersion()
+        {
+            return Assembly.GetExecutingAssembly().GetCustomAttribute<AssemblyInformationalVersionAttribute>().InformationalVersion;
+        }
+    }
+}
@@ -4,14 +4,16 @@ using System.Linq;
 using System.Net;
 using System.Threading.Tasks;
 using System.Web;
+using Microsoft.AspNetCore.Authorization;
 using Microsoft.AspNetCore.Mvc;
 using MQTTnet.Server.Mqtt;
 using MQTTnet.Server.Status;

 namespace MQTTnet.Server.Controllers
 {
+    [Authorize]
    [ApiController]
-    public class SessionsController : ControllerBase
+    public class SessionsController : Controller
    {
        private readonly MqttServerService _mqttServerService;

@@ -1,6 +1,7 @@
+# MQTTnet
 MIT License

-Copyright (c) 2017 Christian Kratky
+Copyright (c) 2019 MQTTnet Team

 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
@@ -19,3 +20,78 @@ AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 SOFTWARE.
+
+# Swashbuckle
+Copyright (c) 2013, Richard Morris
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
+
+1. Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
+
+2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
+
+3. Neither the name of the copyright holder nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE
+
+# IronPython
+Copyright (c) .NET Foundation and Contributors
+           All Rights Reserved
+
+Apache License
+Version 2.0, January 2004
+http://www.apache.org/licenses/ 
+
+TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION 
+
+1. Definitions.
+
+"License" shall mean the terms and conditions for use, reproduction, and distribution as defined by Sections 1 through 9 of this document. 
+
+"Licensor" shall mean the copyright owner or entity authorized by the copyright owner that is granting the License. 
+
+"Legal Entity" shall mean the union of the acting entity and all other entities that control, are controlled by, or are under common control with that entity. For the purposes of this definition, "control" means (i) the power, direct or indirect, to cause the direction or management of such entity, whether by contract or otherwise, or (ii) ownership of fifty percent (50%) or more of the outstanding shares, or (iii) beneficial ownership of such entity. 
+
+"You" (or "Your") shall mean an individual or Legal Entity exercising permissions granted by this License. 
+
+"Source" form shall mean the preferred form for making modifications, including but not limited to software source code, documentation source, and configuration files. 
+
+"Object" form shall mean any form resulting from mechanical transformation or translation of a Source form, including but not limited to compiled object code, generated documentation, and conversions to other media types. 
+
+"Work" shall mean the work of authorship, whether in Source or Object form, made available under the License, as indicated by a copyright notice that is included in or attached to the work (an example is provided in the Appendix below). 
+
+"Derivative Works" shall mean any work, whether in Source or Object form, that is based on (or derived from) the Work and for which the editorial revisions, annotations, elaborations, or other modifications represent, as a whole, an original work of authorship. For the purposes of this License, Derivative Works shall not include works that remain separable from, or merely link (or bind by name) to the interfaces of, the Work and Derivative Works thereof. 
+
+"Contribution" shall mean any work of authorship, including the original version of the Work and any modifications or additions to that Work or Derivative Works thereof, that is intentionally submitted to Licensor for inclusion in the Work by the copyright owner or by an individual or Legal Entity authorized to submit on behalf of the copyright owner. For the purposes of this definition, "submitted" means any form of electronic, verbal, or written communication sent to the Licensor or its representatives, including but not limited to communication on electronic mailing lists, source code control systems, and issue tracking systems that are managed by, or on behalf of, the Licensor for the purpose of discussing and improving the Work, but excluding communication that is conspicuously marked or otherwise designated in writing by the copyright owner as "Not a Contribution." 
+
+"Contributor" shall mean Licensor and any individual or Legal Entity on behalf of whom a Contribution has been received by Licensor and subsequently incorporated within the Work. 
+
+2. Grant of Copyright License. Subject to the terms and conditions of this License, each Contributor hereby grants to You a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare Derivative Works of, publicly display, publicly perform, sublicense, and distribute the Work and such Derivative Works in Source or Object form. 
+
+3. Grant of Patent License. Subject to the terms and conditions of this License, each Contributor hereby grants to You a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable (except as stated in this section) patent license to make, have made, use, offer to sell, sell, import, and otherwise transfer the Work, where such license applies only to those patent claims licensable by such Contributor that are necessarily infringed by their Contribution(s) alone or by combination of their Contribution(s) with the Work to which such Contribution(s) was submitted. If You institute patent litigation against any entity (including a cross-claim or counterclaim in a lawsuit) alleging that the Work or a Contribution incorporated within the Work constitutes direct or contributory patent infringement, then any patent licenses granted to You under this License for that Work shall terminate as of the date such litigation is filed. 
+
+4. Redistribution. You may reproduce and distribute copies of the Work or Derivative Works thereof in any medium, with or without modifications, and in Source or Object form, provided that You meet the following conditions: 
+
+You must give any other recipients of the Work or Derivative Works a copy of this License; and 
+
+
+You must cause any modified files to carry prominent notices stating that You changed the files; and 
+
+
+You must retain, in the Source form of any Derivative Works that You distribute, all copyright, patent, trademark, and attribution notices from the Source form of the Work, excluding those notices that do not pertain to any part of the Derivative Works; and 
+
+
+If the Work includes a "NOTICE" text file as part of its distribution, then any Derivative Works that You distribute must include a readable copy of the attribution notices contained within such NOTICE file, excluding those notices that do not pertain to any part of the Derivative Works, in at least one of the following places: within a NOTICE text file distributed as part of the Derivative Works; within the Source form or documentation, if provided along with the Derivative Works; or, within a display generated by the Derivative Works, if and wherever such third-party notices normally appear. The contents of the NOTICE file are for informational purposes only and do not modify the License. You may add Your own attribution notices within Derivative Works that You distribute, alongside or as an addendum to the NOTICE text from the Work, provided that such additional attribution notices cannot be construed as modifying the License. 
+You may add Your own copyright statement to Your modifications and may provide additional or different license terms and conditions for use, reproduction, or distribution of Your modifications, or for any such Derivative Works as a whole, provided Your use, reproduction, and distribution of the Work otherwise complies with the conditions stated in this License. 
+
+5. Submission of Contributions. Unless You explicitly state otherwise, any Contribution intentionally submitted for inclusion in the Work by You to the Licensor shall be under the terms and conditions of this License, without any additional terms or conditions. Notwithstanding the above, nothing herein shall supersede or modify the terms of any separate license agreement you may have executed with Licensor regarding such Contributions. 
+
+6. Trademarks. This License does not grant permission to use the trade names, trademarks, service marks, or product names of the Licensor, except as required for reasonable and customary use in describing the origin of the Work and reproducing the content of the NOTICE file. 
+
+7. Disclaimer of Warranty. Unless required by applicable law or agreed to in writing, Licensor provides the Work (and each Contributor provides its Contributions) on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied, including, without limitation, any warranties or conditions of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A PARTICULAR PURPOSE. You are solely responsible for determining the appropriateness of using or redistributing the Work and assume any risks associated with Your exercise of permissions under this License. 
+
+8. Limitation of Liability. In no event and under no legal theory, whether in tort (including negligence), contract, or otherwise, unless required by applicable law (such as deliberate and grossly negligent acts) or agreed to in writing, shall any Contributor be liable to You for damages, including any direct, indirect, special, incidental, or consequential damages of any character arising as a result of this License or out of the use or inability to use the Work (including but not limited to damages for loss of goodwill, work stoppage, computer failure or malfunction, or any and all other commercial damages or losses), even if such Contributor has been advised of the possibility of such damages. 
+
+9. Accepting Warranty or Additional Liability. While redistributing the Work or Derivative Works thereof, You may choose to offer, and charge a fee for, acceptance of support, warranty, indemnity, or other liability obligations and/or rights consistent with this License. However, in accepting such obligations, You may act only on Your own behalf and on Your sole responsibility, not on behalf of any other Contributor, and only if You agree to indemnify, defend, and hold each Contributor harmless for any liability incurred by, or claims asserted against, such Contributor by reason of your accepting any such warranty or additional liability. 
+
@@ -1,4 +1,4 @@
-<Project Sdk="Microsoft.NET.Sdk.Web">
+<Project Sdk="Microsoft.NET.Sdk.Web">

  <PropertyGroup>
    <TargetFramework>netcoreapp2.2</TargetFramework>
@@ -14,11 +14,13 @@
    <SignAssembly>false</SignAssembly>
    <DelaySign>false</DelaySign>
    <LangVersion>latest</LangVersion>
+    <Version>1.0.0</Version>
    <TypeScriptToolsVersion>3.3</TypeScriptToolsVersion>
  </PropertyGroup>

  <PropertyGroup>
    <StartupObject></StartupObject>
+    <UserSecretsId>c564f0de-28b4-45bf-b726-4d665d705653</UserSecretsId>
  </PropertyGroup>

  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|AnyCPU'">
@@ -27,6 +29,13 @@
    <NoWarn>1701;1702</NoWarn>
  </PropertyGroup>

+  <ItemGroup>
+    <Compile Remove="wwwroot\**" />
+    <Content Remove="wwwroot\**" />
+    <EmbeddedResource Remove="wwwroot\**" />
+    <None Remove="wwwroot\**" />
+  </ItemGroup>
+
  <ItemGroup>
    <Content Update="appsettings.json">
      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
@@ -53,22 +62,23 @@
    <None Update="LICENSE">
      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
    </None>
-    <None Update="run.sh">
+    <None Update="README.md">
      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
    </None>
-    <None Update="run.bat">
-      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
-    </None>
-    <None Update="Scripts\readme.md">
+    <None Update="Scripts\README.md">
      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
    </None>
    <None Update="Scripts\00_sample.py">
      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
    </None>
+    <None Update="Web\authorization_handler.py">
+      <CopyToOutputDirectory>Always</CopyToOutputDirectory>
+    </None>
  </ItemGroup>

  <ItemGroup>
-    <Folder Include="wwwroot\" />
+    <Folder Include="Properties\PublishProfiles\" />
+    <Folder Include="Web\wwwroot\" />
  </ItemGroup>

 </Project>
@@ -12,7 +12,7 @@ namespace MQTTnet.Server.Mqtt
    {
        private readonly MqttFactory _mqttFactory;

-        public CustomMqttFactory(SettingsModel settings, ILogger<MqttServer> logger)
+        public CustomMqttFactory(MqttSettingsModel settings, ILogger<MqttServer> logger)
        {
            if (settings == null) throw new ArgumentNullException(nameof(settings));
            if (logger == null) throw new ArgumentNullException(nameof(logger));
@@ -22,14 +22,17 @@ namespace MQTTnet.Server.Mqtt
        {
            try
            {
+                var sessionItems = (PythonDictionary)context.SessionItems[MqttServerConnectionValidator.WrappedSessionItemsKey];
+
                var pythonContext = new PythonDictionary
                {
+                    { "client_id", context.ClientId },
+                    { "session_items", sessionItems },
+                    { "retain", context.ApplicationMessage.Retain },
                    { "accept_publish", context.AcceptPublish },
                    { "close_connection", context.CloseConnection },
-                    { "client_id", context.ClientId },
                    { "topic", context.ApplicationMessage.Topic },
-                    { "qos", (int)context.ApplicationMessage.QualityOfServiceLevel },
-                    { "retain", context.ApplicationMessage.Retain }
+                    { "qos", (int)context.ApplicationMessage.QualityOfServiceLevel }
                };
                
                _pythonScriptHostService.InvokeOptionalFunction("on_intercept_application_message", pythonContext);
@@ -7,12 +7,14 @@ using MQTTnet.Server.Scripting;

 namespace MQTTnet.Server.Mqtt
 {
-    public class MqttConnectionValidator : IMqttServerConnectionValidator
+    public class MqttServerConnectionValidator : IMqttServerConnectionValidator
    {
+        public const string WrappedSessionItemsKey = "WRAPPED_ITEMS";
+
        private readonly PythonScriptHostService _pythonScriptHostService;
        private readonly ILogger _logger;

-        public MqttConnectionValidator(PythonScriptHostService pythonScriptHostService, ILogger<MqttConnectionValidator> logger)
+        public MqttServerConnectionValidator(PythonScriptHostService pythonScriptHostService, ILogger<MqttServerConnectionValidator> logger)
        {
            _pythonScriptHostService = pythonScriptHostService ?? throw new ArgumentNullException(nameof(pythonScriptHostService));
            _logger = logger ?? throw new ArgumentNullException(nameof(logger));
@@ -22,23 +24,35 @@ namespace MQTTnet.Server.Mqtt
        {
            try
            {
+                var sessionItems = new PythonDictionary();
+
                var pythonContext = new PythonDictionary
                {
-                    { "client_id", context.ClientId },
                    { "endpoint", context.Endpoint },
                    { "is_secure_connection", context.IsSecureConnection },
+                    { "client_id", context.ClientId },
                    { "username", context.Username },
                    { "password", context.Password },
-                    { "result", PythonConvert.Pythonfy(context.ReturnCode) }
+                    { "raw_password", new Bytes(context.RawPassword ?? new byte[0]) },
+                    { "clean_session", context.CleanSession},
+                    { "authentication_method", context.AuthenticationMethod},
+                    { "authentication_data", new Bytes(context.AuthenticationData ?? new byte[0]) },
+                    { "session_items", sessionItems },
+
+                    { "result", PythonConvert.Pythonfy(context.ReasonCode) }
                };

                _pythonScriptHostService.InvokeOptionalFunction("on_validate_client_connection", pythonContext);

-                context.ReturnCode = PythonConvert.ParseEnum<MqttConnectReturnCode>((string)pythonContext["result"]);
+                context.ReasonCode = PythonConvert.ParseEnum<MqttConnectReasonCode>((string)pythonContext["result"]);
+
+                context.SessionItems[WrappedSessionItemsKey] = sessionItems;
            }
            catch (Exception exception)
            {
                _logger.LogError(exception, "Error while validating client connection.");
+
+                context.ReasonCode = MqttConnectReasonCode.UnspecifiedError;
            }

            return Task.CompletedTask;
@@ -23,34 +23,34 @@ namespace MQTTnet.Server.Mqtt
    {
        private readonly ILogger<MqttServerService> _logger;

-        private readonly SettingsModel _settings;
+        private readonly MqttSettingsModel _settings;
        private readonly MqttApplicationMessageInterceptor _mqttApplicationMessageInterceptor;
        private readonly MqttServerStorage _mqttServerStorage;
        private readonly MqttClientConnectedHandler _mqttClientConnectedHandler;
        private readonly MqttClientDisconnectedHandler _mqttClientDisconnectedHandler;
        private readonly MqttClientSubscribedTopicHandler _mqttClientSubscribedTopicHandler;
        private readonly MqttClientUnsubscribedTopicHandler _mqttClientUnsubscribedTopicHandler;
-        private readonly MqttConnectionValidator _mqttConnectionValidator;
+        private readonly MqttServerConnectionValidator _mqttConnectionValidator;
        private readonly IMqttServer _mqttServer;
        private readonly MqttSubscriptionInterceptor _mqttSubscriptionInterceptor;
        private readonly PythonScriptHostService _pythonScriptHostService;
        private readonly MqttWebSocketServerAdapter _webSocketServerAdapter;

        public MqttServerService(
-            SettingsModel settings,
+            MqttSettingsModel mqttSettings,
            CustomMqttFactory mqttFactory,
            MqttClientConnectedHandler mqttClientConnectedHandler,
            MqttClientDisconnectedHandler mqttClientDisconnectedHandler,
            MqttClientSubscribedTopicHandler mqttClientSubscribedTopicHandler,
            MqttClientUnsubscribedTopicHandler mqttClientUnsubscribedTopicHandler,
-            MqttConnectionValidator mqttConnectionValidator,
+            MqttServerConnectionValidator mqttConnectionValidator,
            MqttSubscriptionInterceptor mqttSubscriptionInterceptor,
            MqttApplicationMessageInterceptor mqttApplicationMessageInterceptor,
            MqttServerStorage mqttServerStorage,
            PythonScriptHostService pythonScriptHostService,            
            ILogger<MqttServerService> logger)
        {
-            _settings = settings ?? throw new ArgumentNullException(nameof(settings));
+            _settings = mqttSettings ?? throw new ArgumentNullException(nameof(mqttSettings));
            _mqttClientConnectedHandler = mqttClientConnectedHandler ?? throw new ArgumentNullException(nameof(mqttClientConnectedHandler));
            _mqttClientDisconnectedHandler = mqttClientDisconnectedHandler ?? throw new ArgumentNullException(nameof(mqttClientDisconnectedHandler));
            _mqttClientSubscribedTopicHandler = mqttClientSubscribedTopicHandler ?? throw new ArgumentNullException(nameof(mqttClientSubscribedTopicHandler));
@@ -66,7 +66,10 @@ namespace MQTTnet.Server.Mqtt

            var adapters = new List<IMqttServerAdapter>
            {
-                new MqttTcpServerAdapter(mqttFactory.Logger.CreateChildLogger()),
+                new MqttTcpServerAdapter(mqttFactory.Logger.CreateChildLogger())
+                {
+                    TreatSocketOpeningErrorAsWarning = true // Opening other ports than for HTTP is not allows in Azure App Services.
+                },
                _webSocketServerAdapter
            };

@@ -14,27 +14,28 @@ namespace MQTTnet.Server.Mqtt
    {
        private readonly List<MqttApplicationMessage> _messages = new List<MqttApplicationMessage>();

-        private readonly SettingsModel _settings;
+        private readonly MqttSettingsModel _mqttSettings;
        private readonly ILogger<MqttServerStorage> _logger;

-        private string _filename;
+        private string _path;
        private bool _messagesHaveChanged;

-        public MqttServerStorage(SettingsModel settings, ILogger<MqttServerStorage> logger)
+        public MqttServerStorage(MqttSettingsModel mqttSettings, ILogger<MqttServerStorage> logger)
        {
-            _settings = settings ?? throw new ArgumentNullException(nameof(settings));
+            _mqttSettings = mqttSettings ?? throw new ArgumentNullException(nameof(mqttSettings));
            _logger = logger ?? throw new ArgumentNullException(nameof(logger));
        }

        public void Configure()
        {
-            if (_settings.RetainedApplicationMessages?.Persist != true)
+            if (_mqttSettings.RetainedApplicationMessages?.Persist != true || 
+                string.IsNullOrEmpty(_mqttSettings.RetainedApplicationMessages.Path))
            {
                _logger.LogInformation("Persisting of retained application messages is disabled.");
                return;
            }

-            _filename = ExpandFilename();
+            _path = PathHelper.ExpandPath(_mqttSettings.RetainedApplicationMessages.Path);

            // The retained application messages are stored in a separate thread.
            // This is mandatory because writing them to a slow storage (like RaspberryPi SD card) 
@@ -61,7 +62,7 @@ namespace MQTTnet.Server.Mqtt
            {
                try
                {
-                    await Task.Delay(TimeSpan.FromSeconds(_settings.RetainedApplicationMessages.WriteInterval)).ConfigureAwait(false);
+                    await Task.Delay(TimeSpan.FromSeconds(_mqttSettings.RetainedApplicationMessages.WriteInterval)).ConfigureAwait(false);

                    List<MqttApplicationMessage> messages;
                    lock (_messages)
@@ -76,7 +77,7 @@ namespace MQTTnet.Server.Mqtt
                    }

                    var json = JsonConvert.SerializeObject(messages);
-                    await File.WriteAllTextAsync(_filename, json, Encoding.UTF8).ConfigureAwait(false);
+                    await File.WriteAllTextAsync(_path, json, Encoding.UTF8).ConfigureAwait(false);
                    
                    _logger.LogInformation($"{messages.Count} retained MQTT messages written.");
                }
@@ -89,19 +90,19 @@ namespace MQTTnet.Server.Mqtt

        public async Task<IList<MqttApplicationMessage>> LoadRetainedMessagesAsync()
        {
-            if (_settings.RetainedApplicationMessages?.Persist != true)
+            if (_mqttSettings.RetainedApplicationMessages?.Persist != true)
            {
                return null;
            }

-            if (!File.Exists(_filename))
+            if (!File.Exists(_path))
            {
                return null;
            }

            try
            {
-                var json = await File.ReadAllTextAsync(_filename).ConfigureAwait(false);
+                var json = await File.ReadAllTextAsync(_path).ConfigureAwait(false);
                var applicationMessages = JsonConvert.DeserializeObject<List<MqttApplicationMessage>>(json);

                _logger.LogInformation($"{applicationMessages.Count} retained MQTT messages loaded.");
@@ -114,18 +115,5 @@ namespace MQTTnet.Server.Mqtt
                return null;
            }
        }
-
-        private string ExpandFilename()
-        {
-            var filename = _settings.RetainedApplicationMessages.Filename;
-
-            var uri = new Uri(filename, UriKind.RelativeOrAbsolute);
-            if (!uri.IsAbsoluteUri)
-            {
-                filename = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, filename);
-            }
-
-            return filename;
-        }
    }
 }
@@ -21,14 +21,16 @@ namespace MQTTnet.Server.Mqtt
        {
            try
            {
+                var sessionItems = (PythonDictionary)context.SessionItems[MqttServerConnectionValidator.WrappedSessionItemsKey];
+
                var pythonContext = new PythonDictionary
                {
-                    { "accept_subscription", context.AcceptSubscription },
-                    { "close_connection", context.CloseConnection },
-
                    { "client_id", context.ClientId },
+                    { "session_items", sessionItems },
                    { "topic", context.TopicFilter.Topic },
-                    { "qos", (int)context.TopicFilter.QualityOfServiceLevel }
+                    { "qos", (int)context.TopicFilter.QualityOfServiceLevel },
+                    { "accept_subscription", context.AcceptSubscription },
+                    { "close_connection", context.CloseConnection }
                };

                _pythonScriptHostService.InvokeOptionalFunction("on_intercept_subscription", pythonContext);
@@ -2,6 +2,7 @@
 using System.Reflection;
 using Microsoft.AspNetCore;
 using Microsoft.AspNetCore.Hosting;
+using MQTTnet.Server.Web;

 namespace MQTTnet.Server
 {
@@ -27,45 +28,40 @@ namespace MQTTnet.Server
        private static void PrintLogo()
        {
            Console.ResetColor();
-            Console.ForegroundColor = ConsoleColor.White;
-            Console.BackgroundColor = ConsoleColor.Red;
+            Console.ForegroundColor = ConsoleColor.Red;
            const string LogoText =
-@"|                                                                                      |
-|      __  __  ____ _______ _______         _      _____                               |
-|     |  \/  |/ __ \__   __|__   __|       | |    / ____|                              |
-|     | \  / | |  | | | |     | |_ __   ___| |_  | (___   ___ _ ____   _____ _ __      |
-|     | |\/| | |  | | | |     | | '_ \ / _ \ __|  \___ \ / _ \ '__\ \ / / _ \ '__|     |
-|     | |  | | |__| | | |     | | | | |  __/ |_   ____) |  __/ |   \ V /  __/ |        |
-|     |_|  |_|\___\_\ |_|     |_|_| |_|\___|\__| |_____/ \___|_|    \_/ \___|_|        |
-|                                                                                      |
-|                                                                                      |";
+@"
+
+███╗   ███╗ ██████╗ ████████╗████████╗███╗   ██╗███████╗████████╗    ███████╗███████╗██████╗ ██╗   ██╗███████╗██████╗ 
+████╗ ████║██╔═══██╗╚══██╔══╝╚══██╔══╝████╗  ██║██╔════╝╚══██╔══╝    ██╔════╝██╔════╝██╔══██╗██║   ██║██╔════╝██╔══██╗
+██╔████╔██║██║   ██║   ██║      ██║   ██╔██╗ ██║█████╗     ██║       ███████╗█████╗  ██████╔╝██║   ██║█████╗  ██████╔╝
+██║╚██╔╝██║██║▄▄ ██║   ██║      ██║   ██║╚██╗██║██╔══╝     ██║       ╚════██║██╔══╝  ██╔══██╗╚██╗ ██╔╝██╔══╝  ██╔══██╗
+██║ ╚═╝ ██║╚██████╔╝   ██║      ██║   ██║ ╚████║███████╗   ██║       ███████║███████╗██║  ██║ ╚████╔╝ ███████╗██║  ██║
+╚═╝     ╚═╝ ╚══▀▀═╝    ╚═╝      ╚═╝   ╚═╝  ╚═══╝╚══════╝   ╚═╝       ╚══════╝╚══════╝╚═╝  ╚═╝  ╚═══╝  ╚══════╝╚═╝  ╚═╝
+                                                                                                                      
+";

            Console.WriteLine(LogoText);
            Console.ResetColor();
            Console.WriteLine();
            Console.ForegroundColor = ConsoleColor.White;
-            Console.WriteLine(@"
-          -- The official MQTT server implementation of MQTTnet --
-                 Copyright (c) 2017-2019 The MQTTnet Team");
-
-            Console.ForegroundColor = ConsoleColor.Blue;
-            Console.WriteLine(@"
-                   https://github.com/chkr1011/MQTTnet");
+            Console.WriteLine("The official MQTT server implementation of MQTTnet");
+            Console.WriteLine("Copyright (c) 2017-2019 The MQTTnet Team");
+            Console.WriteLine(@"https://github.com/chkr1011/MQTTnet");

            Console.ForegroundColor = ConsoleColor.White;
            Console.WriteLine($@"
- Version:    {Assembly.GetExecutingAssembly().GetName().Version}
- License:    MIT (read LICENSE file)
- Sponsoring: https://opencollective.com/mqttnet
- Support:    https://github.com/chkr1011/MQTTnet/issues
- Docs:       https://github.com/chkr1011/MQTTnet/wiki/MQTTnetServer
+Version:    {Assembly.GetExecutingAssembly().GetCustomAttribute<AssemblyInformationalVersionAttribute>().InformationalVersion}
+License:    MIT (read LICENSE file)
+Sponsoring: https://opencollective.com/mqttnet
+Support:    https://github.com/chkr1011/MQTTnet/issues
+Docs:       https://github.com/chkr1011/MQTTnet/wiki/MQTTnetServer
 ");

-            Console.BackgroundColor = ConsoleColor.White;
            Console.ForegroundColor = ConsoleColor.Red;
            Console.WriteLine(" ! THIS IS AN ALPHA VERSION! IT IS NOT RECOMMENDED TO USE IT FOR ANY DIFFERENT PURPOSE THAN TESTING OR EVALUATING!");
-            Console.WriteLine();
            Console.ResetColor();
+            Console.WriteLine();
        }
    }
 }
@@ -0,0 +1,10 @@
+# Starting portable version
+The portable version requires a local installation of the .net core runtime. With that runtime installed the server can be started via the following comand.
+
+dotnet .\MQTTnet.Server.dll
+
+# Starting self contained versions
+The self contained versions are fully portable versions including the .net core runtime. The server can be started using the contained executable files.
+
+Windows:    MQTTnet.Server.exe
+Linux:		MQTTnet.Server (must be set to _executable_ first)
@@ -1 +0,0 @@
-[{"Topic":"a","Payload":"YWFzYXNhc2E=","QualityOfServiceLevel":0,"Retain":true,"UserProperties":[],"ContentType":null,"ResponseTopic":null,"PayloadFormatIndicator":null,"MessageExpiryInterval":null,"TopicAlias":null,"CorrelationData":null,"SubscriptionIdentifier":null},{"Topic":"fgdfgd","Payload":"YWFzYXNhc2E=","QualityOfServiceLevel":0,"Retain":true,"UserProperties":[],"ContentType":null,"ResponseTopic":null,"PayloadFormatIndicator":null,"MessageExpiryInterval":null,"TopicAlias":null,"CorrelationData":null,"SubscriptionIdentifier":null}]
@@ -4,9 +4,12 @@ using System.Dynamic;
 using System.IO;
 using System.Linq;
 using System.Text;
+using System.Threading;
+using System.Threading.Tasks;
 using Microsoft.Extensions.Logging;
 using Microsoft.Scripting;
 using Microsoft.Scripting.Hosting;
+using MQTTnet.Server.Configuration;

 namespace MQTTnet.Server.Scripting
 {
@@ -14,26 +17,27 @@ namespace MQTTnet.Server.Scripting
    {
        private readonly IDictionary<string, object> _proxyObjects = new ExpandoObject();
        private readonly List<PythonScriptInstance> _scriptInstances = new List<PythonScriptInstance>();
+        private readonly string _scriptsPath;
+        private readonly ScriptingSettingsModel _scriptingSettings;
        private readonly ILogger<PythonScriptHostService> _logger;
        private readonly ScriptEngine _scriptEngine;
        
-        public PythonScriptHostService(PythonIOStream pythonIOStream, ILogger<PythonScriptHostService> logger)
+        public PythonScriptHostService(ScriptingSettingsModel scriptingSettings, PythonIOStream pythonIOStream, ILogger<PythonScriptHostService> logger)
        {
+            _scriptingSettings = scriptingSettings ?? throw new ArgumentNullException(nameof(scriptingSettings));
            _logger = logger ?? throw new ArgumentNullException(nameof(logger));

            _scriptEngine = IronPython.Hosting.Python.CreateEngine();
            _scriptEngine.Runtime.IO.SetOutput(pythonIOStream, Encoding.UTF8);
+
+            _scriptsPath = PathHelper.ExpandPath(scriptingSettings.ScriptsPath);
        }

        public void Configure()
        {
            AddSearchPaths(_scriptEngine);

-            var scriptsDirectory = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "Scripts");
-            foreach (var filename in Directory.GetFiles(scriptsDirectory, "*.py", SearchOption.AllDirectories).OrderBy(file => file))
-            {
-                TryInitializeScript(filename);
-            }
+            TryInitializeScriptsAsync().GetAwaiter().GetResult();
        }

        public void RegisterProxyObject(string name, object @object)
@@ -58,35 +62,109 @@ namespace MQTTnet.Server.Scripting
                    }
                    catch (Exception exception)
                    {
-                        _logger.LogError(exception, $"Error while invoking function '{name}' at script '{pythonScriptInstance.Name}'.");
+                        _logger.LogError(exception, $"Error while invoking function '{name}' at script '{pythonScriptInstance.Uid}'.");
                    }
                }
            }
        }

-        private void TryInitializeScript(string filename)
+        public List<string> GetScriptUids()
        {
-            try
+            lock (_scriptInstances)
            {
-                var scriptName = new FileInfo(filename).Name;
-
-                _logger.LogTrace($"Initializing Python script '{scriptName}'...");
-                var code = File.ReadAllText(filename);
-
-                var scriptInstance = CreateScriptInstance(scriptName, code);
-                scriptInstance.InvokeOptionalFunction("initialize");
-
-                _scriptInstances.Add(scriptInstance);
-
-                _logger.LogInformation($"Initialized script '{scriptName}'.");
-            }
-            catch (Exception exception)
-            {
-                _logger.LogError(exception, $"Error while initializing script '{new FileInfo(filename).Name}'.");
+                return _scriptInstances.Select(si => si.Uid).ToList();
            }
        }

-        private PythonScriptInstance CreateScriptInstance(string name, string code)
+        public Task<string> ReadScriptAsync(string uid, CancellationToken cancellationToken)
+        {
+            if (uid == null) throw new ArgumentNullException(nameof(uid));
+
+            string path;
+
+            lock (_scriptInstances)
+            {
+                path = _scriptInstances.FirstOrDefault(si => si.Uid == uid)?.Path;
+            }
+
+            if (path == null || !File.Exists(path))
+            {
+                return null;
+            }
+
+            return File.ReadAllTextAsync(path, Encoding.UTF8, cancellationToken);
+        }
+
+        public async Task WriteScriptAsync(string uid, string code, CancellationToken cancellationToken)
+        {
+            var path = Path.Combine(_scriptsPath, uid + ".py");
+
+            await File.WriteAllTextAsync(path, code, Encoding.UTF8, cancellationToken).ConfigureAwait(false);
+            await TryInitializeScriptsAsync().ConfigureAwait(false);
+        }
+
+        public async Task DeleteScriptAsync(string uid)
+        {
+            var path = Path.Combine(_scriptsPath, uid + ".py");
+
+            if (File.Exists(path))
+            {
+                File.Delete(path);
+                await TryInitializeScriptsAsync().ConfigureAwait(false);
+            }
+        }
+
+        public async Task TryInitializeScriptsAsync()
+        {
+            lock (_scriptInstances)
+            {
+                foreach (var scriptInstance in _scriptInstances)
+                {
+                    try
+                    {
+                        scriptInstance.InvokeOptionalFunction("destroy");
+                    }
+                    catch (Exception exception)
+                    {
+                        _logger.LogWarning(exception, $"Error while unloading script '{scriptInstance.Uid}'.");
+                    }
+                }
+
+                _scriptInstances.Clear();
+            }
+
+            foreach (var path in Directory.GetFiles(_scriptsPath, "*.py", SearchOption.AllDirectories).OrderBy(file => file))
+            {
+                await TryInitializeScriptAsync(path).ConfigureAwait(false);
+            }
+        }
+
+        private async Task TryInitializeScriptAsync(string path)
+        {
+            var uid = new FileInfo(path).Name.Replace(".py", string.Empty, StringComparison.OrdinalIgnoreCase);
+
+            try
+            {
+                _logger.LogTrace($"Initializing Python script '{uid}'...");
+                var code = await File.ReadAllTextAsync(path).ConfigureAwait(false);
+
+                var scriptInstance = CreateScriptInstance(uid, path, code);
+                scriptInstance.InvokeOptionalFunction("initialize");
+
+                lock (_scriptInstances)
+                {
+                    _scriptInstances.Add(scriptInstance);
+                }
+                
+                _logger.LogInformation($"Initialized script '{uid}'.");
+            }
+            catch (Exception exception)
+            {
+                _logger.LogError(exception, $"Error while initializing script '{uid}'.");
+            }
+        }
+
+        private PythonScriptInstance CreateScriptInstance(string uid, string path, string code)
        {
            var scriptScope = _scriptEngine.CreateScope();

@@ -96,31 +174,26 @@ namespace MQTTnet.Server.Scripting
            scriptScope.SetVariable("mqtt_net_server", _proxyObjects);
            compiledCode.Execute(scriptScope);
            
-            return new PythonScriptInstance(name, scriptScope);
+            return new PythonScriptInstance(uid, path, scriptScope);
        }

        private void AddSearchPaths(ScriptEngine scriptEngine)
        {
-            var paths = new List<string>
+            if (_scriptingSettings.IncludePaths?.Any() != true)
            {
-                Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "Lib"),
-                "/usr/lib/python2.7",
-                @"C:\Python27\Lib"
-            };
-            
-            AddSearchPaths(scriptEngine, paths);
-        }
+                return;
+            }

-        private void AddSearchPaths(ScriptEngine scriptEngine, IEnumerable<string> paths)
-        {
            var searchPaths = scriptEngine.GetSearchPaths();

-            foreach (var path in paths)
+            foreach (var path in _scriptingSettings.IncludePaths)
            {
-                if (Directory.Exists(path))
+                var effectivePath = PathHelper.ExpandPath(path);
+
+                if (Directory.Exists(effectivePath))
                {
-                    searchPaths.Add(path);
-                    _logger.LogInformation($"Added Python lib path: {path}");
+                    searchPaths.Add(effectivePath);
+                    _logger.LogInformation($"Added Python lib path: {effectivePath}");
                }
            }

@@ -8,14 +8,17 @@ namespace MQTTnet.Server.Scripting
    {
        private readonly ScriptScope _scriptScope;

-        public PythonScriptInstance(string name, ScriptScope scriptScope)
+        public PythonScriptInstance(string uid, string path, ScriptScope scriptScope)
        {
-            _scriptScope = scriptScope;
+            Uid = uid;
+            Path = path;

-            Name = name;
+            _scriptScope = scriptScope;
        }

-        public string Name { get; }
+        public string Uid { get; }
+
+        public string Path { get; }

        public bool InvokeOptionalFunction(string name, params object[] parameters)
        {
@@ -7,9 +7,17 @@ def initialize():
    It will be executed only one time.
    """

-    print("Hello World from Sample script.")
+    print("Hello World from sample script.")
   

+def destroy():
+    """
+    This function is invoked when the script is unloaded due to a script file update etc.
+    """
+
+    print("Bye from sample script.")
+
+    
 def on_validate_client_connection(context):
    """
    This function is invoked whenever a client wants to connect. It can be used to validate the connection.
@@ -17,20 +25,45 @@ def on_validate_client_connection(context):
    
    print(context)

+    # Access some custom data here which was inserted upon connect and may use it for validation.
    mqtt_net_server.write_shared_data(context["client_id"], {"custom_value_1": 1, "custom_value_2": True})

    return
+    
+    # Supported results:
+    # * success
+    # * unspecified_error
+    # * malformed_packet
+    # * protocol_error
+    # * implementation_specific_error
+    # * unsupported_protocol_version
+    # * client_identifier_not_valid
+    # * bad_user_name_or_password
+    # * not_authorized
+    # * server_unavailable
+    # * server_busy
+    # * banned
+    # * bad_authentication_method
+    # * topic_name_invalid
+    # * packet_too_large
+    # * quota_exceeded
+    # * payload_format_invalid
+    # * retain_not_supported
+    # * qos_not_supported
+    # * use_another_server
+    # * server_moved
+    # * connection_rate_exceeded

    if context["client_id"] != "test_client":
-        context["result"] = "connection_refused_not_authorized"
+        context["result"] = "bad_user_name_or_password"
        return

    if context["username"] != "bud spencer":
-        context["result"] = "connection_refused_not_authorized"
+        context["result"] = "bad_user_name_or_password"
        return

-    if context["password"] != "secret":
-        context["result"] = "connection_refused_not_authorized"
+    if context["password_string"] != "secret":
+        context["result"] = "bad_user_name_or_password"

    print(context)

@@ -1,9 +1,11 @@
-This directory contains scripts which are loaded by the server and can be used to perform the following tasks.
+# MQTT Scripts

-1. Validation of client connections via credentials, client IDs etc.
-2. Manipulation of every processed message.
-3. Validation of subscription attempts.
-4. Publishing of custom application messages.
+This directory contains scripts which are loaded by the server and can be used to perform the following tasks.
+
+* Validation of client connections via credentials, client IDs etc.
+* Manipulation of every processed message.
+* Validation of subscription attempts.
+* Publishing of custom application messages.

 All scripts are loaded and _MQTTnet Server_ will invoke functions according to predefined naming conventions.
 If a function is implemented in multiple scripts the context will be moved throug all instances. This allows overriding of results or passing data to other (following) scripts.
@@ -0,0 +1,118 @@
+using System;
+using System.IO;
+using System.Net.Http.Headers;
+using System.Security.Claims;
+using System.Text;
+using System.Text.Encodings.Web;
+using System.Threading.Tasks;
+using IronPython.Runtime;
+using Microsoft.AspNetCore.Authentication;
+using Microsoft.Extensions.Logging;
+using Microsoft.Extensions.Options;
+using Microsoft.Net.Http.Headers;
+using Microsoft.Scripting;
+
+namespace MQTTnet.Server.Web
+{
+    public class AuthenticationHandler : AuthenticationHandler<AuthenticationSchemeOptions>
+    {
+        private readonly ILogger<AuthenticationHandler> _logger;
+
+        public AuthenticationHandler(
+            IOptionsMonitor<AuthenticationSchemeOptions> options,
+            ILoggerFactory loggerFactory,
+            UrlEncoder encoder,
+            ISystemClock clock,
+            ILogger<AuthenticationHandler> logger)
+            : base(options, loggerFactory, encoder, clock)
+        {
+            _logger = logger ?? throw new ArgumentNullException(nameof(logger));
+        }
+
+        protected override async Task<AuthenticateResult> HandleAuthenticateAsync()
+        {
+            if (!Request.Headers.ContainsKey(HeaderNames.Authorization))
+            {
+                return AuthenticateResult.NoResult();
+            }
+
+            try
+            {
+                var headerValue = Request.Headers[HeaderNames.Authorization];
+                var parsedHeaderValue = AuthenticationHeaderValue.Parse(Request.Headers[HeaderNames.Authorization]);
+
+                var scheme = parsedHeaderValue.Scheme;
+                var parameter = parsedHeaderValue.Parameter;
+                string username = null;
+                string password = null;
+
+                if (scheme.Equals("Basic", StringComparison.OrdinalIgnoreCase))
+                {
+                    var credentialBytes = Convert.FromBase64String(parsedHeaderValue.Parameter);
+                    var credentials = Encoding.UTF8.GetString(credentialBytes).Split(':');
+                    username = credentials[0];
+                    password = credentials[1];
+                }
+
+                var context = new PythonDictionary
+                {
+                    ["header_value"] = headerValue,
+                    ["scheme"] = scheme,
+                    ["parameter"] = parameter,
+                    ["username"] = username,
+                    ["password"] = password,
+                    ["is_authenticated"] = false
+                };
+
+                if (!ValidateUser(context))
+                {
+                    return AuthenticateResult.Fail("Invalid credentials.");
+                }
+
+                var claims = new[]
+                {
+                    new Claim(ClaimTypes.NameIdentifier, context.get("username") as string ?? string.Empty)
+                };
+
+                var identity = new ClaimsIdentity(claims, Scheme.Name);
+                var principal = new ClaimsPrincipal(identity);
+                var ticket = new AuthenticationTicket(principal, Scheme.Name);
+
+                return AuthenticateResult.Success(ticket);
+            }
+            catch (Exception exception)
+            {
+                _logger.LogWarning("Error while authenticating user.", exception);
+
+                return AuthenticateResult.Fail(exception);
+            }
+            finally
+            {
+                await Task.CompletedTask;
+            }
+        }
+
+        private bool ValidateUser(PythonDictionary context)
+        {
+            var handlerPath = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "Web", "authorization_handler.py");
+            if (!File.Exists(handlerPath))
+            {
+                return false;
+            }
+
+            var code = File.ReadAllText(handlerPath);
+
+            var scriptEngine = IronPython.Hosting.Python.CreateEngine();
+            //scriptEngine.Runtime.IO.SetOutput(new PythonIOStream(_logger.), Encoding.UTF8);
+
+            var scriptScope = scriptEngine.CreateScope();
+            var scriptSource = scriptScope.Engine.CreateScriptSourceFromString(code, SourceCodeKind.File);
+            var compiledCode = scriptSource.Compile();
+            compiledCode.Execute(scriptScope);
+            var function = scriptScope.Engine.Operations.GetMember<PythonFunction>(scriptScope, "handle_authenticate");
+            scriptScope.Engine.Operations.Invoke(function, context);
+
+            return context.get("is_authenticated", false) as bool? == true;
+        }
+    }
+}
@@ -0,0 +1,20 @@
+using System;
+using System.IO;
+using System.Text;
+using Microsoft.AspNetCore.Http;
+
+namespace MQTTnet.Server.Web
+{
+    public static class Extensions
+    {
+        public static string ReadBodyAsString(this HttpRequest request)
+        {
+            if (request == null) throw new ArgumentNullException(nameof(request));
+
+            using (var reader = new StreamReader(request.Body, Encoding.UTF8))
+            {
+                return reader.ReadToEnd();
+            }
+        }
+    }
+}
@@ -1,10 +1,14 @@
 using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Net;
+using Microsoft.AspNetCore.Authentication;
 using Microsoft.AspNetCore.Builder;
 using Microsoft.AspNetCore.Hosting;
 using Microsoft.AspNetCore.Mvc;
-using Microsoft.EntityFrameworkCore.Internal;
 using Microsoft.Extensions.Configuration;
 using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Net.Http.Headers;
 using Microsoft.OpenApi.Models;
 using Microsoft.Scripting.Utils;
 using MQTTnet.Server.Configuration;
@@ -14,7 +18,7 @@ using MQTTnet.Server.Scripting;
 using MQTTnet.Server.Scripting.DataSharing;
 using Swashbuckle.AspNetCore.SwaggerUI;

-namespace MQTTnet.Server
+namespace MQTTnet.Server.Web
 {
    public class Startup
    {
@@ -35,7 +39,7 @@ namespace MQTTnet.Server
            MqttServerService mqttServerService,
            PythonScriptHostService pythonScriptHostService,
            DataSharingService dataSharingService,
-            SettingsModel settings)
+            MqttSettingsModel mqttSettings)
        {
            if (environment.IsDevelopment())
            {
@@ -46,12 +50,20 @@ namespace MQTTnet.Server
                application.UseHsts();
            }

+            application.UseCors(x => x
+                .AllowAnyOrigin()
+                .AllowAnyMethod()
+                .AllowAnyHeader()
+                .AllowCredentials());
+
+            application.UseAuthentication();
+
            application.UseStaticFiles();

            application.UseHttpsRedirection();
            application.UseMvc();

-            ConfigureWebSocketEndpoint(application, mqttServerService, settings);
+            ConfigureWebSocketEndpoint(application, mqttServerService, mqttSettings);

            dataSharingService.Configure();
            pythonScriptHostService.Configure();
@@ -73,6 +85,8 @@ namespace MQTTnet.Server

        public void ConfigureServices(IServiceCollection services)
        {
+            services.AddCors();
+
            services.AddMvc()
                .SetCompatibilityVersion(CompatibilityVersion.Version_2_2)
                .AddJsonOptions(options =>
@@ -80,7 +94,7 @@ namespace MQTTnet.Server
                    options.SerializerSettings.Converters.Add(new Newtonsoft.Json.Converters.StringEnumConverter());
                });

-            services.AddSingleton(ReadSettings());
+            ReadMqttSettings(services);

            services.AddSingleton<PythonIOStream>();
            services.AddSingleton<PythonScriptHostService>();
@@ -95,13 +109,29 @@ namespace MQTTnet.Server
            services.AddSingleton<MqttClientDisconnectedHandler>();
            services.AddSingleton<MqttClientSubscribedTopicHandler>();
            services.AddSingleton<MqttClientUnsubscribedTopicHandler>();
-            services.AddSingleton<MqttConnectionValidator>();
+            services.AddSingleton<MqttServerConnectionValidator>();
            services.AddSingleton<MqttSubscriptionInterceptor>();
            services.AddSingleton<MqttApplicationMessageInterceptor>();
-            
+
            services.AddSwaggerGen(c =>
            {
                c.DescribeAllEnumsAsStrings();
+                
+                var securityScheme = new OpenApiSecurityScheme
+                {
+                    Scheme = "Basic",
+                    Name = HeaderNames.Authorization,
+                    Type = SecuritySchemeType.Http,
+                    In = ParameterLocation.Header
+                };
+
+                c.AddSecurityDefinition("Swagger", securityScheme);
+
+                c.AddSecurityRequirement(new OpenApiSecurityRequirement
+                {
+                    [securityScheme] = new List<string>()
+                });
+
                c.SwaggerDoc("v1", new OpenApiInfo
                {
                    Title = "MQTTnet.Server API",
@@ -120,46 +150,54 @@ namespace MQTTnet.Server
                    },
                });
            });
+
+            services.AddAuthentication("Basic")
+                .AddScheme<AuthenticationSchemeOptions, AuthenticationHandler>("Basic", null)
+                .AddCookie();
        }

-        private SettingsModel ReadSettings()
+        private void ReadMqttSettings(IServiceCollection services)
        {
-            var settings = new Configuration.SettingsModel();
-            Configuration.Bind("MQTT", settings);
-            return settings;
+            var mqttSettings = new MqttSettingsModel();
+            Configuration.Bind("MQTT", mqttSettings);
+            services.AddSingleton(mqttSettings);
+
+            var scriptingSettings = new ScriptingSettingsModel();
+            Configuration.Bind("Scripting", scriptingSettings);
+            services.AddSingleton(scriptingSettings);
        }

        private static void ConfigureWebSocketEndpoint(
            IApplicationBuilder application,
            MqttServerService mqttServerService,
-            SettingsModel settings)
+            MqttSettingsModel mqttSettings)
        {
-            if (settings?.WebSocketEndPoint?.Enabled != true)
+            if (mqttSettings?.WebSocketEndPoint?.Enabled != true)
            {
                return;
            }

-            if (string.IsNullOrEmpty(settings.WebSocketEndPoint.Path))
+            if (string.IsNullOrEmpty(mqttSettings.WebSocketEndPoint.Path))
            {
                return;
            }

            var webSocketOptions = new WebSocketOptions
            {
-                KeepAliveInterval = TimeSpan.FromSeconds(settings.WebSocketEndPoint.KeepAliveInterval),
-                ReceiveBufferSize = settings.WebSocketEndPoint.ReceiveBufferSize
+                KeepAliveInterval = TimeSpan.FromSeconds(mqttSettings.WebSocketEndPoint.KeepAliveInterval),
+                ReceiveBufferSize = mqttSettings.WebSocketEndPoint.ReceiveBufferSize
            };

-            if (settings.WebSocketEndPoint.AllowedOrigins?.Any() == true)
+            if (mqttSettings.WebSocketEndPoint.AllowedOrigins?.Any() == true)
            {
-                webSocketOptions.AllowedOrigins.AddRange(settings.WebSocketEndPoint.AllowedOrigins);
+                webSocketOptions.AllowedOrigins.AddRange(mqttSettings.WebSocketEndPoint.AllowedOrigins);
            }
-            
+
            application.UseWebSockets(webSocketOptions);

            application.Use(async (context, next) =>
            {
-                if (context.Request.Path == settings.WebSocketEndPoint.Path)
+                if (context.Request.Path == mqttSettings.WebSocketEndPoint.Path)
                {
                    if (context.WebSockets.IsWebSocketRequest)
                    {
@@ -170,7 +208,7 @@ namespace MQTTnet.Server
                    }
                    else
                    {
-                        context.Response.StatusCode = 400;
+                        context.Response.StatusCode = (int)HttpStatusCode.BadRequest;
                    }
                }
                else
@@ -0,0 +1,20 @@
+def handle_authenticate(context):
+    """
+    This function is invoked whenever a user tries to access protected HTTP resources.
+    This function must exist and return a proper value. Otherwise the request is denied.
+    All authentication data must be sent via using the "Authorization" header. This header
+    will be parsed and all values will be exposed to the context. 
+    """
+    header_value = context["header_value"] # The untouched header value.
+
+    scheme = context["scheme"]
+    parameter = context["parameter"]
+
+    username = context["username"] # Only set if proper "Basic" authorization is used.
+    password = context["password"] # Only set if proper "Basic" authorization is used.
+    
+    context["is_authenticated"] = True # Change this to _False_ in case of invalid credentials.
+
+    # Example for an API key with proper format.
+    if header_value == "APIKey 123456":
+        context["is_authenticated"] = True
@@ -2,10 +2,10 @@
    "Kestrel": {
        "EndPoints": {
            "Http": {
-                "Url": "http://localhost:80"
+                "Url": "http://*:80"
            },
            "Https": {
-                "Url": "http://localhost:443"
+                "Url": "http://*:443"
            }
        }
    },
@@ -37,15 +37,23 @@
            "AllowedOrigins": [] // List of strings with URLs.
        },
        "CommunicationTimeout": 15, // In seconds.
-        "ConnectionBacklog": 0, /* Set 0 to disable */
-        "EnablePersistentSessions": false,
+        "ConnectionBacklog": 10, // Set 0 to disable
+        "EnablePersistentSessions": true,
        "MaxPendingMessagesPerClient": 250,
        "RetainedApplicationMessages": {
            "Persist": true,
-            "Filename": "RetainedApplicationMessages.json",
+            "Path": "RetainedApplicationMessages.json",
            "WriteInterval": 10 // In seconds.
        },
-        "EnableDebugLogging": true
+        "EnableDebugLogging": false
+    },
+    "Scripting": {
+        "ScriptsPath": "Scripts",
+        "IncludePaths": [
+            "Lib",
+            "/usr/lib/python2.7",
+            "C:\\Python27\\Lib"
+        ]
    },
    "Logging": {
        "LogLevel": {
@@ -1,2 +0,0 @@
-@echo off
-START "MQTTnet Server" dotnet .\MQTTnet.Server.dll
@@ -1,3 +0,0 @@
-#!/bin/bash
-echo "Starting MQTTnet Server.."
-dotnet .\MQTTnet.Server.dll
@@ -1,4 +1,5 @@
 using System;
+using System.Security.Cryptography.X509Certificates;
 using System.Threading;
 using System.Threading.Tasks;
 using MQTTnet.Formatter;
@@ -12,6 +13,8 @@ namespace MQTTnet.Adapter

        bool IsSecureConnection { get; }

+        X509Certificate2 ClientCertificate { get; }
+
        MqttPacketFormatterAdapter PacketFormatterAdapter { get; }

        long BytesSent { get; }
@@ -29,5 +32,7 @@ namespace MQTTnet.Adapter
        Task SendPacketAsync(MqttBasePacket packet, TimeSpan timeout, CancellationToken cancellationToken);

        Task<MqttBasePacket> ReceivePacketAsync(TimeSpan timeout, CancellationToken cancellationToken);
+
+        void ResetStatistics();
    }
 }
@@ -2,6 +2,7 @@ using System;
 using System.IO;
 using System.Net.Sockets;
 using System.Runtime.InteropServices;
+using System.Security.Cryptography.X509Certificates;
 using System.Threading;
 using System.Threading.Tasks;
 using MQTTnet.Channel;
@@ -47,6 +48,8 @@ namespace MQTTnet.Adapter

        public bool IsSecureConnection => _channel.IsSecureConnection;

+        public X509Certificate2 ClientCertificate => _channel.ClientCertificate;
+
        public MqttPacketFormatterAdapter PacketFormatterAdapter { get; }

        public long BytesSent => Interlocked.Read(ref _bytesSent);
@@ -1,4 +1,5 @@
 using System;
+using System.Security.Cryptography.X509Certificates;
 using System.Threading;
 using System.Threading.Tasks;

@@ -8,6 +9,7 @@ namespace MQTTnet.Channel
    {
        string Endpoint { get; }
        bool IsSecureConnection { get; }
+        X509Certificate2 ClientCertificate { get; }

        Task ConnectAsync(CancellationToken cancellationToken);
        Task DisconnectAsync(CancellationToken cancellationToken);
@@ -1,9 +1,45 @@
-namespace MQTTnet.Client.Connecting
+using System.Collections.Generic;
+using MQTTnet.Packets;
+
+namespace MQTTnet.Client.Connecting
 {
+    // TODO: Consider renaming this to _MqttClientConnectResult_
    public class MqttClientAuthenticateResult
    {
+        public MqttClientConnectResultCode ResultCode { get; set; }
+
        public bool IsSessionPresent { get; set; }

-        public MqttClientConnectResultCode ResultCode { get; set; }
+        public bool? WildcardSubscriptionAvailable { get; set; }
+
+        public bool? RetainAvailable { get; set; }
+
+        public string AssignedClientIdentifier { get; set; }
+
+        public string AuthenticationMethod { get; set; }
+
+        public byte[] AuthenticationData { get; set; }
+
+        public uint? MaximumPacketSize { get; set; }
+
+        public string ReasonString { get; set; }
+
+        public ushort? ReceiveMaximum { get; set; }
+
+        public string ResponseInformation { get; set; }
+
+        public ushort? TopicAliasMaximum { get; set; }
+
+        public string ServerReference { get; set; }
+
+        public ushort? ServerKeepAlive { get; set; }
+
+        public uint? SessionExpiryInterval { get; set; }
+
+        public bool? SubscriptionIdentifiersAvailable { get; set; }
+
+        public bool? SharedSubscriptionAvailable { get; set; }
+
+        public List<MqttUserProperty> UserProperties { get; set; }
    }
 }
@@ -0,0 +1,9 @@
+using System.Threading.Tasks;
+
+namespace MQTTnet.Client.ExtendedAuthenticationExchange
+{
+    public interface IMqttExtendedAuthenticationExchangeHandler
+    {
+        Task HandleRequestAsync(MqttExtendedAuthenticationExchangeContext context);
+    }
+}
@@ -0,0 +1,35 @@
+using System;
+using System.Collections.Generic;
+using MQTTnet.Packets;
+using MQTTnet.Protocol;
+
+namespace MQTTnet.Client.ExtendedAuthenticationExchange
+{
+    public class MqttExtendedAuthenticationExchangeContext
+    {
+        public MqttExtendedAuthenticationExchangeContext(MqttAuthPacket authPacket, IMqttClient client)
+        {
+            if (authPacket == null) throw new ArgumentNullException(nameof(authPacket));
+
+            ReasonCode = authPacket.ReasonCode;
+            ReasonString = authPacket.Properties?.ReasonString;
+            AuthenticationMethod = authPacket.Properties?.AuthenticationMethod;
+            AuthenticationData = authPacket.Properties?.AuthenticationData;
+            UserProperties = authPacket.Properties?.UserProperties;
+
+            Client = client ?? throw new ArgumentNullException(nameof(client));
+        }
+
+        public MqttAuthenticateReasonCode ReasonCode { get; }
+
+        public string ReasonString { get; }
+
+        public string AuthenticationMethod { get; }
+
+        public byte[] AuthenticationData { get; }
+
+        public List<MqttUserProperty> UserProperties { get; }
+
+        public IMqttClient Client { get; }
+    }
+}
@@ -0,0 +1,17 @@
+using System.Collections.Generic;
+using MQTTnet.Packets;
+using MQTTnet.Protocol;
+
+namespace MQTTnet.Client.ExtendedAuthenticationExchange
+{
+    public class MqttExtendedAuthenticationExchangeData
+    {
+        public MqttAuthenticateReasonCode ReasonCode { get; set; }
+
+        public string ReasonString { get; set; }
+
+        public byte[] AuthenticationData { get; set; }
+
+        public List<MqttUserProperty> UserProperties { get; }
+    }
+}
@@ -3,6 +3,7 @@ using System.Threading;
 using System.Threading.Tasks;
 using MQTTnet.Client.Connecting;
 using MQTTnet.Client.Disconnecting;
+using MQTTnet.Client.ExtendedAuthenticationExchange;
 using MQTTnet.Client.Options;
 using MQTTnet.Client.Subscribing;
 using MQTTnet.Client.Unsubscribing;
@@ -21,6 +22,7 @@ namespace MQTTnet.Client
        Task<MqttClientAuthenticateResult> ConnectAsync(IMqttClientOptions options, CancellationToken cancellationToken);
        Task DisconnectAsync(MqttClientDisconnectOptions options, CancellationToken cancellationToken);

+        Task SendExtendedAuthenticationExchangeDataAsync(MqttExtendedAuthenticationExchangeData data, CancellationToken cancellationToken);
        Task<MqttClientSubscribeResult> SubscribeAsync(MqttClientSubscribeOptions options, CancellationToken cancellationToken);
        Task<MqttClientUnsubscribeResult> UnsubscribeAsync(MqttClientUnsubscribeOptions options, CancellationToken cancellationToken);
    }
@@ -5,6 +5,8 @@ namespace MQTTnet.Client
 {
    public interface IMqttClientFactory
    {
+        IMqttFactory UseClientAdapterFactory(IMqttClientAdapterFactory clientAdapterFactory);
+
        IMqttClient CreateMqttClient();

        IMqttClient CreateMqttClient(IMqttNetLogger logger);
@@ -5,6 +5,7 @@ using System.Threading.Tasks;
 using MQTTnet.Adapter;
 using MQTTnet.Client.Connecting;
 using MQTTnet.Client.Disconnecting;
+using MQTTnet.Client.ExtendedAuthenticationExchange;
 using MQTTnet.Client.Options;
 using MQTTnet.Client.Publishing;
 using MQTTnet.Client.Receiving;
@@ -12,6 +13,7 @@ using MQTTnet.Client.Subscribing;
 using MQTTnet.Client.Unsubscribing;
 using MQTTnet.Diagnostics;
 using MQTTnet.Exceptions;
+using MQTTnet.Internal;
 using MQTTnet.PacketDispatcher;
 using MQTTnet.Packets;
 using MQTTnet.Protocol;
@@ -138,6 +140,23 @@ namespace MQTTnet.Client
            }
        }

+        public Task SendExtendedAuthenticationExchangeDataAsync(MqttExtendedAuthenticationExchangeData data, CancellationToken cancellationToken)
+        {
+            if (data == null) throw new ArgumentNullException(nameof(data));
+
+            return SendAsync(new MqttAuthPacket
+            {
+                Properties = new MqttAuthPacketProperties
+                {
+                    // This must always be equal to the value from the CONNECT packet. So we use it here to ensure that.
+                    AuthenticationMethod = Options.AuthenticationMethod, 
+                    AuthenticationData = data.AuthenticationData,
+                    ReasonString = data.ReasonString,
+                    UserProperties = data.UserProperties
+                }
+            }, cancellationToken);
+        }
+
        public async Task<MqttClientSubscribeResult> SubscribeAsync(MqttClientSubscribeOptions options, CancellationToken cancellationToken)
        {
            if (options == null) throw new ArgumentNullException(nameof(options));
@@ -238,12 +257,12 @@ namespace MQTTnet.Client
        {
            var clientWasConnected = IsConnected;

-            InitiateDisconnect();
-
-            IsConnected = false;
+            TryInitiateDisconnect();

            try
            {
+                IsConnected = false;
+
                if (_adapter != null)
                {
                    _logger.Verbose("Disconnecting [Timeout={0}]", Options.CommunicationTimeout);
@@ -269,12 +288,14 @@ namespace MQTTnet.Client
                var disconnectedHandler = DisconnectedHandler;
                if (disconnectedHandler != null)
                {
-                    await disconnectedHandler.HandleDisconnectedAsync(new MqttClientDisconnectedEventArgs(clientWasConnected, exception, authenticateResult)).ConfigureAwait(false);
+                    // This handler must be executed in a new thread because otherwise a dead lock may happen
+                    // when trying to reconnect in that handler etc.
+                    Task.Run(() => disconnectedHandler.HandleDisconnectedAsync(new MqttClientDisconnectedEventArgs(clientWasConnected, exception, authenticateResult))).Forget(_logger);
                }
            }
        }

-        private void InitiateDisconnect()
+        private void TryInitiateDisconnect()
        {
            lock (_disconnectLock)
            {
@@ -341,6 +362,7 @@ namespace MQTTnet.Client

                while (!cancellationToken.IsCancellationRequested)
                {
+                    // Values described here: [MQTT-3.1.2-24].
                    var keepAliveSendInterval = TimeSpan.FromSeconds(Options.KeepAlivePeriod.TotalSeconds * 0.75);
                    if (Options.KeepAliveSendInterval.HasValue)
                    {
@@ -469,8 +491,19 @@ namespace MQTTnet.Client
                }
                else if (packet is MqttDisconnectPacket)
                {
+                    // Also dispatch disconnect to waiting threads to generate a proper exception.
+                    _packetDispatcher.Dispatch(packet);
+
                    await DisconnectAsync(null, cancellationToken).ConfigureAwait(false);
                }
+                else if (packet is MqttAuthPacket authPacket)
+                {
+                    var extendedAuthenticationExchangeHandler = Options.ExtendedAuthenticationExchangeHandler;
+                    if (extendedAuthenticationExchangeHandler != null)
+                    {
+                        await extendedAuthenticationExchangeHandler.HandleRequestAsync(new MqttExtendedAuthenticationExchangeContext(authPacket, this)).ConfigureAwait(false);
+                    }
+                }
                else
                {
                    _packetDispatcher.Dispatch(packet);
@@ -619,4 +652,4 @@ namespace MQTTnet.Client
            return Interlocked.CompareExchange(ref _disconnectGate, 1, 0) != 0;
        }
    }
-}
+}
@@ -4,6 +4,7 @@ using System.Threading;
 using System.Threading.Tasks;
 using MQTTnet.Client.Connecting;
 using MQTTnet.Client.Disconnecting;
+using MQTTnet.Client.ExtendedAuthenticationExchange;
 using MQTTnet.Client.Options;
 using MQTTnet.Client.Publishing;
 using MQTTnet.Client.Receiving;
@@ -170,21 +171,36 @@ namespace MQTTnet.Client

        public static Task<MqttClientAuthenticateResult> ConnectAsync(this IMqttClient client, IMqttClientOptions options)
        {
+            if (client == null) throw new ArgumentNullException(nameof(client));
+
            return client.ConnectAsync(options, CancellationToken.None);
        }

        public static Task DisconnectAsync(this IMqttClient client, MqttClientDisconnectOptions options)
        {
+            if (client == null) throw new ArgumentNullException(nameof(client));
+
            return client.DisconnectAsync(options, CancellationToken.None);
        }

+        public static Task SendExtendedAuthenticationExchangeDataAsync(this IMqttClient client, MqttExtendedAuthenticationExchangeData data)
+        {
+            if (client == null) throw new ArgumentNullException(nameof(client));
+
+            return client.SendExtendedAuthenticationExchangeDataAsync(data, CancellationToken.None);
+        }
+
        public static Task<MqttClientSubscribeResult> SubscribeAsync(this IMqttClient client, MqttClientSubscribeOptions options)
        {
+            if (client == null) throw new ArgumentNullException(nameof(client));
+
            return client.SubscribeAsync(options, CancellationToken.None);
        }

        public static Task<MqttClientUnsubscribeResult> UnsubscribeAsync(this IMqttClient client, MqttClientUnsubscribeOptions options)
        {
+            if (client == null) throw new ArgumentNullException(nameof(client));
+
            return client.UnsubscribeAsync(options, CancellationToken.None);
        }

@@ -2,7 +2,7 @@
 {
    public interface IMqttClientCredentials
    {
-        string Password { get; }
        string Username { get; }
+        byte[] Password { get; }
    }
 }
@@ -1,4 +1,5 @@
 using System;
+using MQTTnet.Client.ExtendedAuthenticationExchange;
 using MQTTnet.Formatter;

 namespace MQTTnet.Client.Options
@@ -8,6 +9,7 @@ namespace MQTTnet.Client.Options
        string ClientId { get; }
        bool CleanSession { get; }
        IMqttClientCredentials Credentials { get; }
+        IMqttExtendedAuthenticationExchangeHandler ExtendedAuthenticationExchangeHandler { get; }
        MqttProtocolVersion ProtocolVersion { get; }
        IMqttClientChannelOptions ChannelOptions { get; }
        
@@ -4,6 +4,6 @@
    {
        public string Username { get; set; }

-        public string Password { get; set; }
+        public byte[] Password { get; set; }
    }
 }
@@ -1,4 +1,5 @@
 using System;
+using MQTTnet.Client.ExtendedAuthenticationExchange;
 using MQTTnet.Formatter;

 namespace MQTTnet.Client.Options
@@ -8,6 +9,7 @@ namespace MQTTnet.Client.Options
        public string ClientId { get; set; } = Guid.NewGuid().ToString("N");
        public bool CleanSession { get; set; } = true;
        public IMqttClientCredentials Credentials { get; set; }
+        public IMqttExtendedAuthenticationExchangeHandler ExtendedAuthenticationExchangeHandler { get; set; }
        public MqttProtocolVersion ProtocolVersion { get; set; } = MqttProtocolVersion.V311;

        public IMqttClientChannelOptions ChannelOptions { get; set; }
@@ -1,5 +1,7 @@
 using System;
 using System.Linq;
+using System.Text;
+using MQTTnet.Client.ExtendedAuthenticationExchange;
 using MQTTnet.Formatter;

 namespace MQTTnet.Client.Options
@@ -115,6 +117,18 @@ namespace MQTTnet.Client.Options
        }

        public MqttClientOptionsBuilder WithCredentials(string username, string password = null)
+        {
+            byte[] passwordBuffer = null;
+
+            if (password != null)
+            {
+                passwordBuffer = Encoding.UTF8.GetBytes(password);
+            }
+
+            return WithCredentials(username, passwordBuffer);
+        }
+
+        public MqttClientOptionsBuilder WithCredentials(string username, byte[] password = null)
        {
            _options.Credentials = new MqttClientCredentials
            {
@@ -125,6 +139,19 @@ namespace MQTTnet.Client.Options
            return this;
        }

+        public MqttClientOptionsBuilder WithCredentials(IMqttClientCredentials credentials)
+        {
+            _options.Credentials = credentials;
+
+            return this;
+        }
+
+        public MqttClientOptionsBuilder WithExtendedAuthenticationExchangeHandler(IMqttExtendedAuthenticationExchangeHandler handler)
+        {
+            _options.ExtendedAuthenticationExchangeHandler = handler;
+            return this;
+        }
+
        public MqttClientOptionsBuilder WithTcpServer(string server, int? port = null)
        {
            _tcpOptions = new MqttClientTcpOptions
@@ -136,6 +163,7 @@ namespace MQTTnet.Client.Options
            return this;
        }

+        // TODO: Consider creating _MqttClientTcpOptionsBuilder_ as overload.
        public MqttClientOptionsBuilder WithTcpServer(Action<MqttClientTcpOptions> optionsBuilder)
        {
            if (optionsBuilder == null) throw new ArgumentNullException(nameof(optionsBuilder));
@@ -10,7 +10,7 @@ namespace MQTTnet.Client.Options

        public int BufferSize { get; set; } = 65536;

-        public bool DualMode { get; set; } = true;
+        public bool? DualMode { get; set; }

        public bool NoDelay { get; set; } = true;

@@ -7,6 +7,8 @@ namespace MQTTnet.Client.Subscribing
    {
        public List<TopicFilter> TopicFilters { get; set; } = new List<TopicFilter>();

-        public List<MqttUserProperty> UserProperties { get; set; } = new List<MqttUserProperty>();
+        public uint? SubscriptionIdentifier { get; set; }
+
+        public List<MqttUserProperty> UserProperties { get; set; }
    }
 }
@@ -0,0 +1,87 @@
+using System;
+using System.Collections.Generic;
+using MQTTnet.Packets;
+using MQTTnet.Protocol;
+
+namespace MQTTnet.Client.Subscribing
+{
+    public class MqttClientSubscribeOptionsBuilder
+    {
+        private readonly MqttClientSubscribeOptions _subscribeOptions = new MqttClientSubscribeOptions();
+
+        public MqttClientSubscribeOptionsBuilder WithUserProperty(string name, string value)
+        {
+            if (name == null) throw new ArgumentNullException(nameof(name));
+            if (value == null) throw new ArgumentNullException(nameof(value));
+
+            if (_subscribeOptions.UserProperties == null)
+            {
+                _subscribeOptions.UserProperties = new List<MqttUserProperty>();
+            }
+
+            _subscribeOptions.UserProperties.Add(new MqttUserProperty(name, value));
+
+            return this;
+        }
+
+        public MqttClientSubscribeOptionsBuilder WithSubscriptionIdentifier(uint? subscriptionIdentifier)
+        {
+            _subscribeOptions.SubscriptionIdentifier = subscriptionIdentifier;
+
+            return this;
+        }
+
+        public MqttClientSubscribeOptionsBuilder WithTopicFilter(
+            string topic,
+            MqttQualityOfServiceLevel qualityOfServiceLevel = MqttQualityOfServiceLevel.AtMostOnce,
+            bool? noLocal = null,
+            bool? retainAsPublished = null,
+            MqttRetainHandling? retainHandling = null)
+        {
+            return WithTopicFilter(new TopicFilter
+            {
+                Topic = topic,
+                QualityOfServiceLevel = qualityOfServiceLevel,
+                NoLocal = noLocal,
+                RetainAsPublished = retainAsPublished,
+                RetainHandling = retainHandling
+            });
+        }
+
+        public MqttClientSubscribeOptionsBuilder WithTopicFilter(Action<TopicFilterBuilder> topicFilterBuilder)
+        {
+            if (topicFilterBuilder == null) throw new ArgumentNullException(nameof(topicFilterBuilder));
+
+            var internalTopicFilterBuilder = new TopicFilterBuilder();
+            topicFilterBuilder(internalTopicFilterBuilder);
+
+            return WithTopicFilter(internalTopicFilterBuilder);
+        }
+
+        public MqttClientSubscribeOptionsBuilder WithTopicFilter(TopicFilterBuilder topicFilterBuilder)
+        {
+            if (topicFilterBuilder == null) throw new ArgumentNullException(nameof(topicFilterBuilder));
+
+            return WithTopicFilter(topicFilterBuilder.Build());
+        }
+
+        public MqttClientSubscribeOptionsBuilder WithTopicFilter(TopicFilter topicFilter)
+        {
+            if (topicFilter == null) throw new ArgumentNullException(nameof(topicFilter));
+
+            if (_subscribeOptions.TopicFilters == null)
+            {
+                _subscribeOptions.TopicFilters = new List<TopicFilter>();
+            }
+
+            _subscribeOptions.TopicFilters.Add(topicFilter);
+
+            return this;
+        }
+
+        public MqttClientSubscribeOptions Build()
+        {
+            return _subscribeOptions;
+        }
+    }
+}
@@ -0,0 +1,29 @@
+using System.Collections.Generic;
+using MQTTnet.Packets;
+using MQTTnet.Protocol;
+
+namespace MQTTnet.Exceptions
+{
+    public class MqttUnexpectedDisconnectReceivedException : MqttCommunicationException
+    {
+        public MqttUnexpectedDisconnectReceivedException(MqttDisconnectPacket disconnectPacket) 
+            : base($"Unexpected DISCONNECT (Reason code={disconnectPacket.ReasonCode}) received.")
+        {
+            ReasonCode = disconnectPacket.ReasonCode;
+            SessionExpiryInterval = disconnectPacket.Properties?.SessionExpiryInterval;
+            ReasonString = disconnectPacket.Properties?.ReasonString;
+            ServerReference = disconnectPacket.Properties?.ServerReference;
+            UserProperties = disconnectPacket.Properties?.UserProperties;
+        }
+
+        public MqttDisconnectReasonCode? ReasonCode { get; }
+
+        public uint? SessionExpiryInterval { get; }
+
+        public string ReasonString { get; }
+
+        public List<MqttUserProperty> UserProperties { get; }
+
+        public string ServerReference { get; }
+    }
+}
@@ -5,6 +5,8 @@ using MQTTnet.Client.Publishing;
 using MQTTnet.Client.Subscribing;
 using MQTTnet.Client.Unsubscribing;
 using MQTTnet.Packets;
+using MQTTnet.Server;
+using MqttClientSubscribeResult = MQTTnet.Client.Subscribing.MqttClientSubscribeResult;

 namespace MQTTnet.Formatter
 {
@@ -20,6 +22,8 @@ namespace MQTTnet.Formatter

        MqttConnectPacket CreateConnectPacket(MqttApplicationMessage willApplicationMessage, IMqttClientOptions options);

+        MqttConnAckPacket CreateConnAckPacket(MqttConnectionValidatorContext connectionValidatorContext);
+
        MqttClientSubscribeResult CreateClientSubscribeResult(MqttSubscribePacket subscribePacket, MqttSubAckPacket subAckPacket);

        MqttClientUnsubscribeResult CreateClientUnsubscribeResult(MqttUnsubscribePacket unsubscribePacket, MqttUnsubAckPacket unsubAckPacket);
@@ -4,9 +4,9 @@ namespace MQTTnet.Formatter
 {
    public interface IMqttPacketBodyReader
    {
-        ulong Length { get; }
+        int Length { get; }

-        ulong Offset { get; }
+        int Offset { get; }

        bool EndOfStream { get; }

@@ -26,6 +26,6 @@ namespace MQTTnet.Formatter

        bool ReadBoolean();

-        void Seek(ulong position);
+        void Seek(int position);
    }
 }
@@ -8,7 +8,6 @@
        void Write(byte returnCode);
        void WriteWithLengthPrefix(byte[] payload);
        void Write(ushort keepAlivePeriod);
-
        void Write(IMqttPacketWriter propertyWriter);
        void WriteVariableLengthInteger(uint length);
        void Write(byte[] payload, int v, int length);
@@ -9,52 +9,42 @@ namespace MQTTnet.Formatter
    public class MqttPacketBodyReader : IMqttPacketBodyReader
    {
        private readonly byte[] _buffer;
-        private readonly ulong _initialOffset;
-        private readonly ulong _length;
+        private readonly int _initialOffset;
+        private readonly int _length;
+
+        private int _offset;

        public MqttPacketBodyReader(byte[] buffer, int offset, int length)
-         : this(buffer, (ulong)offset, (ulong)length)
-        {
-        }
-
-        public MqttPacketBodyReader(byte[] buffer, ulong offset, ulong length)
        {
            _buffer = buffer;
            _initialOffset = offset;
-            Offset = offset;
+            _offset = offset;
            _length = length;
        }

-        public ulong Offset { get; private set; }
+        public int Offset => _offset;

-        public ulong Length => _length - Offset;
+        public int Length => _length - _offset;

-        public bool EndOfStream => Offset == _length;
+        public bool EndOfStream => _offset == _length;

-        public void Seek(ulong position)
+        public void Seek(int position)
        {
-            Offset = _initialOffset + position;
-        }
-
-        public ArraySegment<byte> Read(uint length)
-        {
-            ValidateReceiveBuffer(length);
-
-            var buffer = new ArraySegment<byte>(_buffer, (int)Offset, (int)length);
-            Offset += length;
-            return buffer;
+            _offset = _initialOffset + position;
        }

        public byte ReadByte()
        {
            ValidateReceiveBuffer(1);
-            return _buffer[Offset++];
-        }

+            return _buffer[_offset++];
+        }
+        
        public bool ReadBoolean()
        {
            ValidateReceiveBuffer(1);
-            var buffer = _buffer[Offset++];
+
+            var buffer = _buffer[_offset++];

            if (buffer == 0)
            {
@@ -71,15 +61,19 @@ namespace MQTTnet.Formatter

        public byte[] ReadRemainingData()
        {
-            return new ArraySegment<byte>(_buffer, (int)Offset, (int)(_length - Offset)).ToArray();
+            var bufferLength = _length - _offset;
+            var buffer = new byte[bufferLength];
+            Array.Copy(_buffer, _offset, buffer, 0, bufferLength);
+
+            return buffer;
        }

        public ushort ReadTwoByteInteger()
        {
            ValidateReceiveBuffer(2);

-            var msb = _buffer[Offset++];
-            var lsb = _buffer[Offset++];
+            var msb = _buffer[_offset++];
+            var lsb = _buffer[_offset++];
            
            return (ushort)(msb << 8 | lsb);
        }
@@ -88,31 +82,14 @@ namespace MQTTnet.Formatter
        {
            ValidateReceiveBuffer(4);

-            var byte0 = _buffer[Offset++];
-            var byte1 = _buffer[Offset++];
-            var byte2 = _buffer[Offset++];
-            var byte3 = _buffer[Offset++];
+            var byte0 = _buffer[_offset++];
+            var byte1 = _buffer[_offset++];
+            var byte2 = _buffer[_offset++];
+            var byte3 = _buffer[_offset++];

            return (uint)(byte0 << 24 | byte1 << 16 | byte2 << 8 | byte3);
        }

-        public byte[] ReadWithLengthPrefix()
-        {
-            return ReadSegmentWithLengthPrefix().ToArray();
-        }
-
-        private ArraySegment<byte> ReadSegmentWithLengthPrefix()
-        {
-            var length = ReadTwoByteInteger();
-
-            ValidateReceiveBuffer(length);
-
-            var result = new ArraySegment<byte>(_buffer, (int)Offset, length);
-            Offset += length;
-
-            return result;
-        }
-
        public uint ReadVariableLengthInteger()
        {
            var multiplier = 1;
@@ -134,13 +111,30 @@ namespace MQTTnet.Formatter

            return value;
        }
+        
+        public byte[] ReadWithLengthPrefix()
+        {
+            return ReadSegmentWithLengthPrefix().ToArray();
+        }
+
+        private ArraySegment<byte> ReadSegmentWithLengthPrefix()
+        {
+            var length = ReadTwoByteInteger();
+
+            ValidateReceiveBuffer(length);
+
+            var result = new ArraySegment<byte>(_buffer, _offset, length);
+            _offset += length;
+
+            return result;
+        }

        [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        private void ValidateReceiveBuffer(uint length)
+        private void ValidateReceiveBuffer(int length)
        {
-            if (_length < Offset + length)
+            if (_length < _offset + length)
            {
-                throw new ArgumentOutOfRangeException(nameof(_buffer), $"Expected at least {Offset + length} bytes but there are only {_length} bytes");
+                throw new ArgumentOutOfRangeException(nameof(_buffer), $"Expected at least {_offset + length} bytes but there are only {_length} bytes");
            }
        }

@@ -9,6 +9,8 @@ using MQTTnet.Client.Unsubscribing;
 using MQTTnet.Exceptions;
 using MQTTnet.Packets;
 using MQTTnet.Protocol;
+using MQTTnet.Server;
+using MqttClientSubscribeResult = MQTTnet.Client.Subscribing.MqttClientSubscribeResult;

 namespace MQTTnet.Formatter.V3
 {
@@ -124,6 +126,16 @@ namespace MQTTnet.Formatter.V3
            };
        }

+        public MqttConnAckPacket CreateConnAckPacket(MqttConnectionValidatorContext connectionValidatorContext)
+        {
+            if (connectionValidatorContext == null) throw new ArgumentNullException(nameof(connectionValidatorContext));
+
+            return new MqttConnAckPacket
+            {
+                ReturnCode = new MqttConnectReasonCodeConverter().ToConnectReturnCode(connectionValidatorContext.ReasonCode)
+            };
+        }
+
        public MqttClientSubscribeResult CreateClientSubscribeResult(MqttSubscribePacket subscribePacket, MqttSubAckPacket subAckPacket)
        {
            if (subscribePacket == null) throw new ArgumentNullException(nameof(subscribePacket));
@@ -10,7 +10,11 @@ namespace MQTTnet.Formatter.V3
    public class MqttV310PacketFormatter : IMqttPacketFormatter
    {
        private const int FixedHeaderSize = 1;
-        
+
+        private static readonly MqttPingReqPacket PingReqPacket = new MqttPingReqPacket();
+        private static readonly MqttPingRespPacket PingRespPacket = new MqttPingRespPacket();
+        private static readonly MqttDisconnectPacket DisconnectPacket = new MqttDisconnectPacket();
+
        private readonly IMqttPacketWriter _packetWriter;

        public MqttV310PacketFormatter()
@@ -67,14 +71,14 @@ namespace MQTTnet.Formatter.V3
            {
                case MqttControlPacketType.Connect: return DecodeConnectPacket(receivedMqttPacket.Body);
                case MqttControlPacketType.ConnAck: return DecodeConnAckPacket(receivedMqttPacket.Body);
-                case MqttControlPacketType.Disconnect: return new MqttDisconnectPacket();
+                case MqttControlPacketType.Disconnect: return DisconnectPacket;
                case MqttControlPacketType.Publish: return DecodePublishPacket(receivedMqttPacket);
                case MqttControlPacketType.PubAck: return DecodePubAckPacket(receivedMqttPacket.Body);
                case MqttControlPacketType.PubRec: return DecodePubRecPacket(receivedMqttPacket.Body);
                case MqttControlPacketType.PubRel: return DecodePubRelPacket(receivedMqttPacket.Body);
                case MqttControlPacketType.PubComp: return DecodePubCompPacket(receivedMqttPacket.Body);
-                case MqttControlPacketType.PingReq: return new MqttPingReqPacket();
-                case MqttControlPacketType.PingResp: return new MqttPingRespPacket();
+                case MqttControlPacketType.PingReq: return PingReqPacket;
+                case MqttControlPacketType.PingResp: return PingRespPacket;
                case MqttControlPacketType.Subscribe: return DecodeSubscribePacket(receivedMqttPacket.Body);
                case MqttControlPacketType.SubAck: return DecodeSubAckPacket(receivedMqttPacket.Body);
                case MqttControlPacketType.Unsubscibe: return DecodeUnsubscribePacket(receivedMqttPacket.Body);
@@ -229,7 +233,7 @@ namespace MQTTnet.Formatter.V3

            if (!receivedMqttPacket.Body.EndOfStream)
            {
-                packet.Payload = receivedMqttPacket.Body.ReadRemainingData().ToArray();
+                packet.Payload = receivedMqttPacket.Body.ReadRemainingData();
            }

            return packet;
@@ -289,7 +293,7 @@ namespace MQTTnet.Formatter.V3

            if (passwordFlag)
            {
-                packet.Password = body.ReadStringWithLengthPrefix();
+                packet.Password = body.ReadWithLengthPrefix();
            }

            ValidateConnectPacket(packet);
@@ -10,6 +10,9 @@ using MQTTnet.Client.Unsubscribing;
 using MQTTnet.Exceptions;
 using MQTTnet.Packets;
 using MQTTnet.Protocol;
+using MQTTnet.Server;
+
+using MqttClientSubscribeResult = MQTTnet.Client.Subscribing.MqttClientSubscribeResult;

 namespace MQTTnet.Formatter.V5
 {
@@ -33,13 +36,14 @@ namespace MQTTnet.Formatter.V5
                    MessageExpiryInterval = applicationMessage.MessageExpiryInterval,
                    PayloadFormatIndicator = applicationMessage.PayloadFormatIndicator,
                    ResponseTopic = applicationMessage.ResponseTopic,
-                    SubscriptionIdentifier = applicationMessage.SubscriptionIdentifier,
+                    SubscriptionIdentifiers = applicationMessage.SubscriptionIdentifiers,
                    TopicAlias = applicationMessage.TopicAlias
                }
            };

            if (applicationMessage.UserProperties != null)
            {
+                packet.Properties.UserProperties = new List<MqttUserProperty>();
                packet.Properties.UserProperties.AddRange(applicationMessage.UserProperties);
            }

@@ -67,7 +71,7 @@ namespace MQTTnet.Formatter.V5
                ContentType = publishPacket.Properties?.ContentType,
                CorrelationData = publishPacket.Properties?.CorrelationData,
                MessageExpiryInterval = publishPacket.Properties?.MessageExpiryInterval,
-                SubscriptionIdentifier = publishPacket.Properties?.SubscriptionIdentifier,
+                SubscriptionIdentifiers = publishPacket.Properties?.SubscriptionIdentifiers,
                TopicAlias = publishPacket.Properties?.TopicAlias,
                PayloadFormatIndicator = publishPacket.Properties?.PayloadFormatIndicator,
                UserProperties = publishPacket.Properties?.UserProperties ?? new List<MqttUserProperty>()
@@ -81,7 +85,23 @@ namespace MQTTnet.Formatter.V5
            return new MqttClientAuthenticateResult
            {
                IsSessionPresent = connAckPacket.IsSessionPresent,
-                ResultCode = (MqttClientConnectResultCode)connAckPacket.ReasonCode.Value
+                ResultCode = (MqttClientConnectResultCode)connAckPacket.ReasonCode.Value,
+                WildcardSubscriptionAvailable = connAckPacket.Properties?.WildcardSubscriptionAvailable,
+                RetainAvailable = connAckPacket.Properties?.RetainAvailable,
+                AssignedClientIdentifier = connAckPacket.Properties?.AssignedClientIdentifier,
+                AuthenticationMethod = connAckPacket.Properties?.AuthenticationMethod,
+                AuthenticationData = connAckPacket.Properties?.AuthenticationData,
+                MaximumPacketSize = connAckPacket.Properties?.MaximumPacketSize,
+                ReasonString = connAckPacket.Properties?.ReasonString,
+                ReceiveMaximum = connAckPacket.Properties?.ReceiveMaximum,
+                ResponseInformation = connAckPacket.Properties?.ResponseInformation,
+                TopicAliasMaximum = connAckPacket.Properties?.TopicAliasMaximum,
+                ServerReference = connAckPacket.Properties?.ServerReference,
+                ServerKeepAlive = connAckPacket.Properties?.ServerKeepAlive,
+                SessionExpiryInterval = connAckPacket.Properties?.SessionExpiryInterval,
+                SubscriptionIdentifiersAvailable = connAckPacket.Properties?.SubscriptionIdentifiersAvailable,
+                SharedSubscriptionAvailable = connAckPacket.Properties?.SharedSubscriptionAvailable,
+                UserProperties = connAckPacket.Properties?.UserProperties
            };
        }

@@ -112,6 +132,22 @@ namespace MQTTnet.Formatter.V5
            };
        }

+        public MqttConnAckPacket CreateConnAckPacket(MqttConnectionValidatorContext connectionValidatorContext)
+        {
+            return new MqttConnAckPacket
+            {
+                ReasonCode = connectionValidatorContext.ReasonCode,
+                Properties = new MqttConnAckPacketProperties
+                {
+                    UserProperties = connectionValidatorContext.UserProperties,
+                    AuthenticationMethod = connectionValidatorContext.AuthenticationMethod,
+                    AuthenticationData = connectionValidatorContext.ResponseAuthenticationData,
+                    AssignedClientIdentifier = connectionValidatorContext.AssignedClientIdentifier,
+                    ReasonString = connectionValidatorContext.ReasonString
+                }
+            };
+        }
+
        public MqttClientSubscribeResult CreateClientSubscribeResult(MqttSubscribePacket subscribePacket, MqttSubAckPacket subAckPacket)
        {
            if (subscribePacket == null) throw new ArgumentNullException(nameof(subscribePacket));
@@ -158,7 +194,8 @@ namespace MQTTnet.Formatter.V5
            };

            packet.TopicFilters.AddRange(options.TopicFilters);
-            packet.Properties.UserProperties.AddRange(options.UserProperties);
+            packet.Properties.SubscriptionIdentifier = options.SubscriptionIdentifier;
+            packet.Properties.UserProperties = options.UserProperties;

            return packet;
        }
@@ -173,7 +210,7 @@ namespace MQTTnet.Formatter.V5
            };

            packet.TopicFilters.AddRange(options.TopicFilters);
-            packet.Properties.UserProperties.AddRange(options.UserProperties);
+            packet.Properties.UserProperties = options.UserProperties;

            return packet;
        }
@@ -1,5 +1,5 @@
 using System;
-using System.Linq;
+using System.Collections.Generic;
 using MQTTnet.Adapter;
 using MQTTnet.Exceptions;
 using MQTTnet.Packets;
@@ -9,6 +9,10 @@ namespace MQTTnet.Formatter.V5
 {
    public class MqttV500PacketDecoder
    {
+        private static readonly MqttPingReqPacket PingReqPacket = new MqttPingReqPacket();
+
+        private static readonly MqttPingRespPacket PingRespPacket = new MqttPingRespPacket();
+
        public MqttBasePacket Decode(ReceivedMqttPacket receivedMqttPacket)
        {
            if (receivedMqttPacket == null) throw new ArgumentNullException(nameof(receivedMqttPacket));
@@ -45,10 +49,7 @@ namespace MQTTnet.Formatter.V5
        {
            ThrowIfBodyIsEmpty(body);

-            var packet = new MqttConnectPacket
-            {
-                Properties = new MqttConnectPacketProperties()
-            };
+            var packet = new MqttConnectPacket();

            var protocolName = body.ReadStringWithLengthPrefix();
            var protocolVersion = body.ReadByte();
@@ -83,6 +84,11 @@ namespace MQTTnet.Formatter.V5
            var propertiesReader = new MqttV500PropertiesReader(body);
            while (propertiesReader.MoveNext())
            {
+                if (packet.Properties == null)
+                {
+                    packet.Properties = new MqttConnectPacketProperties();
+                }
+
                if (propertiesReader.CurrentPropertyId == MqttPropertyId.SessionExpiryInterval)
                {
                    packet.Properties.SessionExpiryInterval = propertiesReader.ReadSessionExpiryInterval();
@@ -91,10 +97,6 @@ namespace MQTTnet.Formatter.V5
                {
                    packet.Properties.AuthenticationMethod = propertiesReader.ReadAuthenticationMethod();
                }
-                else if (propertiesReader.CurrentPropertyId == MqttPropertyId.WillDelayInterval)
-                {
-                    packet.Properties.WillDelayInterval = propertiesReader.ReadWillDelayInterval();
-                }
                else if (propertiesReader.CurrentPropertyId == MqttPropertyId.AuthenticationData)
                {
                    packet.Properties.AuthenticationData = propertiesReader.ReadAuthenticationData();
@@ -121,11 +123,16 @@ namespace MQTTnet.Formatter.V5
                }
                else if (propertiesReader.CurrentPropertyId == MqttPropertyId.UserProperty)
                {
-                    propertiesReader.FillUserProperties(packet.Properties.UserProperties);
+                    if (packet.Properties.UserProperties == null)
+                    {
+                        packet.Properties.UserProperties = new List<MqttUserProperty>();
+                    }
+
+                    propertiesReader.AddUserPropertyTo(packet.Properties.UserProperties);
                }
                else
                {
-                    propertiesReader.ThrowInvalidPropertyIdException(typeof(MqttConnAckPacket));
+                    propertiesReader.ThrowInvalidPropertyIdException(typeof(MqttConnectPacket));
                }
            }

@@ -133,6 +140,63 @@ namespace MQTTnet.Formatter.V5

            if (packet.WillMessage != null)
            {
+                var willPropertiesReader = new MqttV500PropertiesReader(body);
+
+                while (willPropertiesReader.MoveNext())
+                {
+                    if (willPropertiesReader.CurrentPropertyId == MqttPropertyId.PayloadFormatIndicator)
+                    {
+                        packet.WillMessage.PayloadFormatIndicator = propertiesReader.ReadPayloadFormatIndicator();
+                    }
+                    else if (willPropertiesReader.CurrentPropertyId == MqttPropertyId.MessageExpiryInterval)
+                    {
+                        packet.WillMessage.MessageExpiryInterval = propertiesReader.ReadMessageExpiryInterval();
+                    }
+                    else if (willPropertiesReader.CurrentPropertyId == MqttPropertyId.TopicAlias)
+                    {
+                        packet.WillMessage.TopicAlias = propertiesReader.ReadTopicAlias();
+                    }
+                    else if (willPropertiesReader.CurrentPropertyId == MqttPropertyId.ResponseTopic)
+                    {
+                        packet.WillMessage.ResponseTopic = propertiesReader.ReadResponseTopic();
+                    }
+                    else if (willPropertiesReader.CurrentPropertyId == MqttPropertyId.CorrelationData)
+                    {
+                        packet.WillMessage.CorrelationData = propertiesReader.ReadCorrelationData();
+                    }
+                    else if (willPropertiesReader.CurrentPropertyId == MqttPropertyId.SubscriptionIdentifier)
+                    {
+                        if (packet.WillMessage.SubscriptionIdentifiers == null)
+                        {
+                            packet.WillMessage.SubscriptionIdentifiers = new List<uint>();
+                        }
+
+                        packet.WillMessage.SubscriptionIdentifiers.Add(propertiesReader.ReadSubscriptionIdentifier());
+                    }
+                    else if (willPropertiesReader.CurrentPropertyId == MqttPropertyId.ContentType)
+                    {
+                        packet.WillMessage.ContentType = propertiesReader.ReadContentType();
+                    }
+                    else if (willPropertiesReader.CurrentPropertyId == MqttPropertyId.WillDelayInterval)
+                    {
+                        // This is a special case!
+                        packet.Properties.WillDelayInterval = propertiesReader.ReadWillDelayInterval();
+                    }
+                    else if (willPropertiesReader.CurrentPropertyId == MqttPropertyId.UserProperty)
+                    {
+                        if (packet.WillMessage.UserProperties == null)
+                        {
+                            packet.WillMessage.UserProperties = new List<MqttUserProperty>();
+                        }
+
+                        propertiesReader.AddUserPropertyTo(packet.Properties.UserProperties);
+                    }
+                    else
+                    {
+                        propertiesReader.ThrowInvalidPropertyIdException(typeof(MqttPublishPacket));
+                    }
+                }
+
                packet.WillMessage.Topic = body.ReadStringWithLengthPrefix();
                packet.WillMessage.Payload = body.ReadWithLengthPrefix();
            }
@@ -144,7 +208,7 @@ namespace MQTTnet.Formatter.V5

            if (passwordFlag)
            {
-                packet.Password = body.ReadStringWithLengthPrefix();
+                packet.Password = body.ReadWithLengthPrefix();
            }

            return packet;
@@ -159,13 +223,17 @@ namespace MQTTnet.Formatter.V5
            var packet = new MqttConnAckPacket
            {
                IsSessionPresent = (acknowledgeFlags & 0x1) > 0,
-                ReasonCode = (MqttConnectReasonCode)body.ReadByte(),
-                Properties = new MqttConnAckPacketProperties()
+                ReasonCode = (MqttConnectReasonCode)body.ReadByte()
            };

            var propertiesReader = new MqttV500PropertiesReader(body);
            while (propertiesReader.MoveNext())
            {
+                if (packet.Properties == null)
+                {
+                    packet.Properties = new MqttConnAckPacketProperties();
+                }
+
                if (propertiesReader.CurrentPropertyId == MqttPropertyId.SessionExpiryInterval)
                {
                    packet.Properties.SessionExpiryInterval = propertiesReader.ReadSessionExpiryInterval();
@@ -186,7 +254,7 @@ namespace MQTTnet.Formatter.V5
                {
                    packet.Properties.ReceiveMaximum = propertiesReader.ReadReceiveMaximum();
                }
-                else if (propertiesReader.CurrentPropertyId == MqttPropertyId.AssignedClientIdentifer)
+                else if (propertiesReader.CurrentPropertyId == MqttPropertyId.AssignedClientIdentifier)
                {
                    packet.Properties.AssignedClientIdentifier = propertiesReader.ReadAssignedClientIdentifier();
                }
@@ -228,7 +296,12 @@ namespace MQTTnet.Formatter.V5
                }
                else if (propertiesReader.CurrentPropertyId == MqttPropertyId.UserProperty)
                {
-                    propertiesReader.FillUserProperties(packet.Properties.UserProperties);
+                    if (packet.Properties.UserProperties == null)
+                    {
+                        packet.Properties.UserProperties = new List<MqttUserProperty>();
+                    }
+
+                    propertiesReader.AddUserPropertyTo(packet.Properties.UserProperties);
                }
                else
                {
@@ -245,13 +318,17 @@ namespace MQTTnet.Formatter.V5

            var packet = new MqttDisconnectPacket
            {
-                ReasonCode = (MqttDisconnectReasonCode)body.ReadByte(),
-                Properties = new MqttDisconnectPacketProperties()
+                ReasonCode = (MqttDisconnectReasonCode)body.ReadByte()
            };

            var propertiesReader = new MqttV500PropertiesReader(body);
            while (propertiesReader.MoveNext())
            {
+                if (packet.Properties == null)
+                {
+                    packet.Properties = new MqttDisconnectPacketProperties();
+                }
+
                if (propertiesReader.CurrentPropertyId == MqttPropertyId.SessionExpiryInterval)
                {
                    packet.Properties.SessionExpiryInterval = propertiesReader.ReadSessionExpiryInterval();
@@ -266,7 +343,12 @@ namespace MQTTnet.Formatter.V5
                }
                else if (propertiesReader.CurrentPropertyId == MqttPropertyId.UserProperty)
                {
-                    propertiesReader.FillUserProperties(packet.Properties.UserProperties);
+                    if (packet.Properties.UserProperties == null)
+                    {
+                        packet.Properties.UserProperties = new List<MqttUserProperty>();
+                    }
+
+                    propertiesReader.AddUserPropertyTo(packet.Properties.UserProperties);
                }
                else
                {
@@ -283,20 +365,29 @@ namespace MQTTnet.Formatter.V5

            var packet = new MqttSubscribePacket
            {
-                PacketIdentifier = body.ReadTwoByteInteger(),
-                Properties = new MqttSubscribePacketProperties()
+                PacketIdentifier = body.ReadTwoByteInteger()
            };

            var propertiesReader = new MqttV500PropertiesReader(body);
            while (propertiesReader.MoveNext())
            {
+                if (packet.Properties == null)
+                {
+                    packet.Properties = new MqttSubscribePacketProperties();
+                }
+
                if (propertiesReader.CurrentPropertyId == MqttPropertyId.SubscriptionIdentifier)
                {
                    packet.Properties.SubscriptionIdentifier = propertiesReader.ReadSubscriptionIdentifier();
                }
                else if (propertiesReader.CurrentPropertyId == MqttPropertyId.UserProperty)
                {
-                    propertiesReader.FillUserProperties(packet.Properties.UserProperties);
+                    if (packet.Properties.UserProperties == null)
+                    {
+                        packet.Properties.UserProperties = new List<MqttUserProperty>();
+                    }
+
+                    propertiesReader.AddUserPropertyTo(packet.Properties.UserProperties);
                }
                else
                {
@@ -333,20 +424,29 @@ namespace MQTTnet.Formatter.V5

            var packet = new MqttSubAckPacket
            {
-                PacketIdentifier = body.ReadTwoByteInteger(),
-                Properties = new MqttSubAckPacketProperties()
+                PacketIdentifier = body.ReadTwoByteInteger()
            };

            var propertiesReader = new MqttV500PropertiesReader(body);
            while (propertiesReader.MoveNext())
            {
+                if (packet.Properties == null)
+                {
+                    packet.Properties = new MqttSubAckPacketProperties();
+                }
+
                if (propertiesReader.CurrentPropertyId == MqttPropertyId.ReasonString)
                {
                    packet.Properties.ReasonString = propertiesReader.ReadReasonString();
                }
                else if (propertiesReader.CurrentPropertyId == MqttPropertyId.UserProperty)
                {
-                    propertiesReader.FillUserProperties(packet.Properties.UserProperties);
+                    if (packet.Properties.UserProperties == null)
+                    {
+                        packet.Properties.UserProperties = new List<MqttUserProperty>();
+                    }
+
+                    propertiesReader.AddUserPropertyTo(packet.Properties.UserProperties);
                }
                else
                {
@@ -369,16 +469,25 @@ namespace MQTTnet.Formatter.V5

            var packet = new MqttUnsubscribePacket
            {
-                PacketIdentifier = body.ReadTwoByteInteger(),
-                Properties = new MqttUnsubscribePacketProperties()
+                PacketIdentifier = body.ReadTwoByteInteger()
            };

            var propertiesReader = new MqttV500PropertiesReader(body);
            while (propertiesReader.MoveNext())
            {
+                if (packet.Properties == null)
+                {
+                    packet.Properties = new MqttUnsubscribePacketProperties();
+                }
+
                if (propertiesReader.CurrentPropertyId == MqttPropertyId.UserProperty)
                {
-                    propertiesReader.FillUserProperties(packet.Properties.UserProperties);
+                    if (packet.Properties.UserProperties == null)
+                    {
+                        packet.Properties.UserProperties = new List<MqttUserProperty>();
+                    }
+
+                    propertiesReader.AddUserPropertyTo(packet.Properties.UserProperties);
                }
                else
                {
@@ -400,20 +509,29 @@ namespace MQTTnet.Formatter.V5

            var packet = new MqttUnsubAckPacket
            {
-                PacketIdentifier = body.ReadTwoByteInteger(),
-                Properties = new MqttUnsubAckPacketProperties()
+                PacketIdentifier = body.ReadTwoByteInteger()
            };

            var propertiesReader = new MqttV500PropertiesReader(body);
            while (propertiesReader.MoveNext())
            {
+                if (packet.Properties == null)
+                {
+                    packet.Properties = new MqttUnsubAckPacketProperties();
+                }
+
                if (propertiesReader.CurrentPropertyId == MqttPropertyId.ReasonString)
                {
                    packet.Properties.ReasonString = propertiesReader.ReadReasonString();
                }
                else if (propertiesReader.CurrentPropertyId == MqttPropertyId.UserProperty)
                {
-                    propertiesReader.FillUserProperties(packet.Properties.UserProperties);
+                    if (packet.Properties.UserProperties == null)
+                    {
+                        packet.Properties.UserProperties = new List<MqttUserProperty>();
+                    }
+
+                    propertiesReader.AddUserPropertyTo(packet.Properties.UserProperties);
                }
                else
                {
@@ -432,12 +550,12 @@ namespace MQTTnet.Formatter.V5

        private static MqttBasePacket DecodePingReqPacket()
        {
-            return new MqttPingReqPacket();
+            return PingReqPacket;
        }

        private static MqttBasePacket DecodePingRespPacket()
        {
-            return new MqttPingRespPacket();
+            return PingRespPacket;
        }

        private static MqttBasePacket DecodePublishPacket(byte header, IMqttPacketBodyReader body)
@@ -453,8 +571,7 @@ namespace MQTTnet.Formatter.V5
                Topic = body.ReadStringWithLengthPrefix(),
                Retain = retain,
                QualityOfServiceLevel = qos,
-                Dup = dup,
-                Properties = new MqttPublishPacketProperties()
+                Dup = dup
            };

            if (qos > 0)
@@ -465,6 +582,11 @@ namespace MQTTnet.Formatter.V5
            var propertiesReader = new MqttV500PropertiesReader(body);
            while (propertiesReader.MoveNext())
            {
+                if (packet.Properties == null)
+                {
+                    packet.Properties = new MqttPublishPacketProperties();
+                }
+
                if (propertiesReader.CurrentPropertyId == MqttPropertyId.PayloadFormatIndicator)
                {
                    packet.Properties.PayloadFormatIndicator = propertiesReader.ReadPayloadFormatIndicator();
@@ -487,7 +609,12 @@ namespace MQTTnet.Formatter.V5
                }
                else if (propertiesReader.CurrentPropertyId == MqttPropertyId.SubscriptionIdentifier)
                {
-                    packet.Properties.SubscriptionIdentifier = propertiesReader.ReadSubscriptionIdentifier();
+                    if (packet.Properties.SubscriptionIdentifiers == null)
+                    {
+                        packet.Properties.SubscriptionIdentifiers = new List<uint>();
+                    }
+
+                    packet.Properties.SubscriptionIdentifiers.Add(propertiesReader.ReadSubscriptionIdentifier());
                }
                else if (propertiesReader.CurrentPropertyId == MqttPropertyId.ContentType)
                {
@@ -495,7 +622,12 @@ namespace MQTTnet.Formatter.V5
                }
                else if (propertiesReader.CurrentPropertyId == MqttPropertyId.UserProperty)
                {
-                    propertiesReader.FillUserProperties(packet.Properties.UserProperties);
+                    if (packet.Properties.UserProperties == null)
+                    {
+                        packet.Properties.UserProperties = new List<MqttUserProperty>();
+                    }
+
+                    propertiesReader.AddUserPropertyTo(packet.Properties.UserProperties);
                }
                else
                {
@@ -505,7 +637,7 @@ namespace MQTTnet.Formatter.V5

            if (!body.EndOfStream)
            {
-                packet.Payload = body.ReadRemainingData().ToArray();
+                packet.Payload = body.ReadRemainingData();
            }

            return packet;
@@ -517,8 +649,7 @@ namespace MQTTnet.Formatter.V5

            var packet = new MqttPubAckPacket
            {
-                PacketIdentifier = body.ReadTwoByteInteger(),
-                Properties = new MqttPubAckPacketProperties()
+                PacketIdentifier = body.ReadTwoByteInteger()
            };

            if (body.EndOfStream)
@@ -532,13 +663,23 @@ namespace MQTTnet.Formatter.V5
            var propertiesReader = new MqttV500PropertiesReader(body);
            while (propertiesReader.MoveNext())
            {
+                if (packet.Properties == null)
+                {
+                    packet.Properties = new MqttPubAckPacketProperties();
+                }
+
                if (propertiesReader.CurrentPropertyId == MqttPropertyId.ReasonString)
                {
                    packet.Properties.ReasonString = propertiesReader.ReadReasonString();
                }
                else if (propertiesReader.CurrentPropertyId == MqttPropertyId.UserProperty)
                {
-                    propertiesReader.FillUserProperties(packet.Properties.UserProperties);
+                    if (packet.Properties.UserProperties == null)
+                    {
+                        packet.Properties.UserProperties = new List<MqttUserProperty>();
+                    }
+
+                    propertiesReader.AddUserPropertyTo(packet.Properties.UserProperties);
                }
                else
                {
@@ -555,8 +696,7 @@ namespace MQTTnet.Formatter.V5

            var packet = new MqttPubRecPacket
            {
-                PacketIdentifier = body.ReadTwoByteInteger(),
-                Properties = new MqttPubRecPacketProperties()
+                PacketIdentifier = body.ReadTwoByteInteger()
            };

            if (body.EndOfStream)
@@ -570,13 +710,23 @@ namespace MQTTnet.Formatter.V5
            var propertiesReader = new MqttV500PropertiesReader(body);
            while (propertiesReader.MoveNext())
            {
+                if (packet.Properties == null)
+                {
+                    packet.Properties = new MqttPubRecPacketProperties();
+                }
+
                if (propertiesReader.CurrentPropertyId == MqttPropertyId.ReasonString)
                {
                    packet.Properties.ReasonString = propertiesReader.ReadReasonString();
                }
                else if (propertiesReader.CurrentPropertyId == MqttPropertyId.UserProperty)
                {
-                    propertiesReader.FillUserProperties(packet.Properties.UserProperties);
+                    if (packet.Properties.UserProperties == null)
+                    {
+                        packet.Properties.UserProperties = new List<MqttUserProperty>();
+                    }
+
+                    propertiesReader.AddUserPropertyTo(packet.Properties.UserProperties);
                }
                else
                {
@@ -593,8 +743,7 @@ namespace MQTTnet.Formatter.V5

            var packet = new MqttPubRelPacket
            {
-                PacketIdentifier = body.ReadTwoByteInteger(),
-                Properties = new MqttPubRelPacketProperties()
+                PacketIdentifier = body.ReadTwoByteInteger()
            };

            if (body.EndOfStream)
@@ -608,13 +757,23 @@ namespace MQTTnet.Formatter.V5
            var propertiesReader = new MqttV500PropertiesReader(body);
            while (propertiesReader.MoveNext())
            {
+                if (packet.Properties == null)
+                {
+                    packet.Properties = new MqttPubRelPacketProperties();
+                }
+
                if (propertiesReader.CurrentPropertyId == MqttPropertyId.ReasonString)
                {
                    packet.Properties.ReasonString = propertiesReader.ReadReasonString();
                }
                else if (propertiesReader.CurrentPropertyId == MqttPropertyId.UserProperty)
                {
-                    propertiesReader.FillUserProperties(packet.Properties.UserProperties);
+                    if (packet.Properties.UserProperties == null)
+                    {
+                        packet.Properties.UserProperties = new List<MqttUserProperty>();
+                    }
+
+                    propertiesReader.AddUserPropertyTo(packet.Properties.UserProperties);
                }
                else
                {
@@ -631,8 +790,7 @@ namespace MQTTnet.Formatter.V5

            var packet = new MqttPubCompPacket
            {
-                PacketIdentifier = body.ReadTwoByteInteger(),
-                Properties = new MqttPubCompPacketProperties()
+                PacketIdentifier = body.ReadTwoByteInteger()
            };

            if (body.EndOfStream)
@@ -646,13 +804,23 @@ namespace MQTTnet.Formatter.V5
            var propertiesReader = new MqttV500PropertiesReader(body);
            while (propertiesReader.MoveNext())
            {
+                if (packet.Properties == null)
+                {
+                    packet.Properties = new MqttPubCompPacketProperties();
+                }
+
                if (propertiesReader.CurrentPropertyId == MqttPropertyId.ReasonString)
                {
                    packet.Properties.ReasonString = propertiesReader.ReadReasonString();
                }
                else if (propertiesReader.CurrentPropertyId == MqttPropertyId.UserProperty)
                {
-                    propertiesReader.FillUserProperties(packet.Properties.UserProperties);
+                    if (packet.Properties.UserProperties == null)
+                    {
+                        packet.Properties.UserProperties = new List<MqttUserProperty>();
+                    }
+
+                    propertiesReader.AddUserPropertyTo(packet.Properties.UserProperties);
                }
                else
                {
@@ -667,10 +835,7 @@ namespace MQTTnet.Formatter.V5
        {
            ThrowIfBodyIsEmpty(body);

-            var packet = new MqttAuthPacket
-            {
-                Properties = new MqttAuthPacketProperties()
-            };
+            var packet = new MqttAuthPacket();

            if (body.EndOfStream)
            {
@@ -683,6 +848,11 @@ namespace MQTTnet.Formatter.V5
            var propertiesReader = new MqttV500PropertiesReader(body);
            while (propertiesReader.MoveNext())
            {
+                if (packet.Properties == null)
+                {
+                    packet.Properties = new MqttAuthPacketProperties();
+                }
+
                if (propertiesReader.CurrentPropertyId == MqttPropertyId.AuthenticationMethod)
                {
                    packet.Properties.AuthenticationMethod = propertiesReader.ReadAuthenticationMethod();
@@ -697,7 +867,12 @@ namespace MQTTnet.Formatter.V5
                }
                else if (propertiesReader.CurrentPropertyId == MqttPropertyId.UserProperty)
                {
-                    propertiesReader.FillUserProperties(packet.Properties.UserProperties);
+                    if (packet.Properties.UserProperties == null)
+                    {
+                        packet.Properties.UserProperties = new List<MqttUserProperty>();
+                    }
+
+                    propertiesReader.AddUserPropertyTo(packet.Properties.UserProperties);
                }
                else
                {
@@ -127,24 +127,38 @@ namespace MQTTnet.Formatter.V5
            var propertiesWriter = new MqttV500PropertiesWriter();
            if (packet.Properties != null)
            {
-                propertiesWriter.WriteWillDelayInterval(packet.Properties.WillDelayInterval);
                propertiesWriter.WriteSessionExpiryInterval(packet.Properties.SessionExpiryInterval);
                propertiesWriter.WriteAuthenticationMethod(packet.Properties.AuthenticationMethod);
                propertiesWriter.WriteAuthenticationData(packet.Properties.AuthenticationData);
                propertiesWriter.WriteRequestProblemInformation(packet.Properties.RequestProblemInformation);
                propertiesWriter.WriteRequestResponseInformation(packet.Properties.RequestResponseInformation);
                propertiesWriter.WriteReceiveMaximum(packet.Properties.ReceiveMaximum);
-                propertiesWriter.WriteTopicAlias(packet.Properties.TopicAliasMaximum);
+                propertiesWriter.WriteTopicAliasMaximum(packet.Properties.TopicAliasMaximum);
                propertiesWriter.WriteMaximumPacketSize(packet.Properties.MaximumPacketSize);
                propertiesWriter.WriteUserProperties(packet.Properties.UserProperties);
            }

-            propertiesWriter.WriteToPacket(packetWriter);
+            propertiesWriter.WriteTo(packetWriter);

            packetWriter.WriteWithLengthPrefix(packet.ClientId);
-
+            
            if (packet.WillMessage != null)
            {
+                var willPropertiesWriter = new MqttV500PropertiesWriter();
+                willPropertiesWriter.WritePayloadFormatIndicator(packet.WillMessage.PayloadFormatIndicator);
+                willPropertiesWriter.WriteMessageExpiryInterval(packet.WillMessage.MessageExpiryInterval);
+                willPropertiesWriter.WriteTopicAlias(packet.WillMessage.TopicAlias);
+                willPropertiesWriter.WriteResponseTopic(packet.WillMessage.ResponseTopic);
+                willPropertiesWriter.WriteCorrelationData(packet.WillMessage.CorrelationData);
+                willPropertiesWriter.WriteSubscriptionIdentifiers(packet.WillMessage.SubscriptionIdentifiers);
+                willPropertiesWriter.WriteContentType(packet.WillMessage.ContentType);
+                willPropertiesWriter.WriteUserProperties(packet.WillMessage.UserProperties);
+                
+                // This is a special case!
+                willPropertiesWriter.WriteWillDelayInterval(packet.Properties?.WillDelayInterval);
+
+                willPropertiesWriter.WriteTo(packetWriter);
+
                packetWriter.WriteWithLengthPrefix(packet.WillMessage.Topic);
                packetWriter.WriteWithLengthPrefix(packet.WillMessage.Payload);
            }
@@ -202,7 +216,7 @@ namespace MQTTnet.Formatter.V5
                propertiesWriter.WriteUserProperties(packet.Properties.UserProperties);
            }

-            propertiesWriter.WriteToPacket(packetWriter);
+            propertiesWriter.WriteTo(packetWriter);

            return MqttPacketWriter.BuildFixedHeader(MqttControlPacketType.ConnAck);
        }
@@ -244,12 +258,12 @@ namespace MQTTnet.Formatter.V5
                propertiesWriter.WriteTopicAlias(packet.Properties.TopicAlias);
                propertiesWriter.WriteResponseTopic(packet.Properties.ResponseTopic);
                propertiesWriter.WriteCorrelationData(packet.Properties.CorrelationData);
-                propertiesWriter.WriteSubscriptionIdentifier(packet.Properties.SubscriptionIdentifier);
+                propertiesWriter.WriteSubscriptionIdentifiers(packet.Properties.SubscriptionIdentifiers);
                propertiesWriter.WriteContentType(packet.Properties.ContentType);
                propertiesWriter.WriteUserProperties(packet.Properties.UserProperties);
            }

-            propertiesWriter.WriteToPacket(packetWriter);
+            propertiesWriter.WriteTo(packetWriter);

            if (packet.Payload?.Length > 0)
            {
@@ -300,7 +314,7 @@ namespace MQTTnet.Formatter.V5
            if (packetWriter.Length > 0 || packet.ReasonCode.Value != MqttPubAckReasonCode.Success)
            {
                packetWriter.Write((byte)packet.ReasonCode.Value);
-                propertiesWriter.WriteToPacket(packetWriter);
+                propertiesWriter.WriteTo(packetWriter);
            }
            
            return MqttPacketWriter.BuildFixedHeader(MqttControlPacketType.PubAck);
@@ -328,7 +342,7 @@ namespace MQTTnet.Formatter.V5
            if (packetWriter.Length > 0 || packet.ReasonCode.Value != MqttPubRecReasonCode.Success)
            {
                packetWriter.Write((byte)packet.ReasonCode.Value);
-                propertiesWriter.WriteToPacket(packetWriter);
+                propertiesWriter.WriteTo(packetWriter);
            }

            return MqttPacketWriter.BuildFixedHeader(MqttControlPacketType.PubRec);
@@ -355,7 +369,7 @@ namespace MQTTnet.Formatter.V5
            if (propertiesWriter.Length > 0 || packet.ReasonCode.Value != MqttPubRelReasonCode.Success)
            {
                packetWriter.Write((byte)packet.ReasonCode.Value);
-                propertiesWriter.WriteToPacket(packetWriter);
+                propertiesWriter.WriteTo(packetWriter);
            }

            return MqttPacketWriter.BuildFixedHeader(MqttControlPacketType.PubRel, 0x02);
@@ -382,7 +396,7 @@ namespace MQTTnet.Formatter.V5
            if (propertiesWriter.Length > 0 || packet.ReasonCode.Value != MqttPubCompReasonCode.Success)
            {
                packetWriter.Write((byte)packet.ReasonCode.Value);
-                propertiesWriter.WriteToPacket(packetWriter);
+                propertiesWriter.WriteTo(packetWriter);
            }

            return MqttPacketWriter.BuildFixedHeader(MqttControlPacketType.PubComp);
@@ -403,7 +417,7 @@ namespace MQTTnet.Formatter.V5
                propertiesWriter.WriteUserProperties(packet.Properties.UserProperties);
            }

-            propertiesWriter.WriteToPacket(packetWriter);
+            propertiesWriter.WriteTo(packetWriter);

            if (packet.TopicFilters?.Count > 0)
            {
@@ -450,7 +464,7 @@ namespace MQTTnet.Formatter.V5
                propertiesWriter.WriteUserProperties(packet.Properties.UserProperties);
            }

-            propertiesWriter.WriteToPacket(packetWriter);
+            propertiesWriter.WriteTo(packetWriter);

            foreach (var reasonCode in packet.ReasonCodes)
            {
@@ -474,7 +488,7 @@ namespace MQTTnet.Formatter.V5
                propertiesWriter.WriteUserProperties(packet.Properties.UserProperties);
            }

-            propertiesWriter.WriteToPacket(packetWriter);
+            propertiesWriter.WriteTo(packetWriter);

            foreach (var topicFilter in packet.TopicFilters)
            {
@@ -499,7 +513,7 @@ namespace MQTTnet.Formatter.V5
                propertiesWriter.WriteUserProperties(packet.Properties.UserProperties);
            }

-            propertiesWriter.WriteToPacket(packetWriter);
+            propertiesWriter.WriteTo(packetWriter);

            foreach (var reasonCode in packet.ReasonCodes)
            {
@@ -527,7 +541,7 @@ namespace MQTTnet.Formatter.V5
                propertiesWriter.WriteUserProperties(packet.Properties.UserProperties);
            }

-            propertiesWriter.WriteToPacket(packetWriter);
+            propertiesWriter.WriteTo(packetWriter);

            return MqttPacketWriter.BuildFixedHeader(MqttControlPacketType.Disconnect);
        }
@@ -555,7 +569,7 @@ namespace MQTTnet.Formatter.V5
                propertiesWriter.WriteUserProperties(packet.Properties.UserProperties);
            }

-            propertiesWriter.WriteToPacket(packetWriter);
+            propertiesWriter.WriteTo(packetWriter);

            return MqttPacketWriter.BuildFixedHeader(MqttControlPacketType.Auth);
        }
@@ -1,6 +1,5 @@
 using System;
 using System.Collections.Generic;
-using System.Linq;
 using MQTTnet.Exceptions;
 using MQTTnet.Packets;
 using MQTTnet.Protocol;
@@ -10,8 +9,8 @@ namespace MQTTnet.Formatter.V5
    public class MqttV500PropertiesReader
    {
        private readonly IMqttPacketBodyReader _body;
-        private readonly uint _length;
-        private readonly ulong _targetOffset;
+        private readonly int _length;
+        private readonly int _targetOffset;

        public MqttV500PropertiesReader(IMqttPacketBodyReader body)
        {
@@ -19,7 +18,7 @@ namespace MQTTnet.Formatter.V5

            if (!body.EndOfStream)
            {
-                _length = body.ReadVariableLengthInteger();
+                _length = (int)body.ReadVariableLengthInteger();
            }

            _targetOffset = body.Offset + _length;
@@ -43,24 +42,14 @@ namespace MQTTnet.Formatter.V5
            return true;
        }

-        public void FillUserProperties(List<MqttUserProperty> userProperties)
+        public void AddUserPropertyTo(List<MqttUserProperty> userProperties)
        {
            if (userProperties == null) throw new ArgumentNullException(nameof(userProperties));

-            var userPropertiesLength = _body.ReadVariableLengthInteger();
-            if (userPropertiesLength == 0)
-            {
-                return;
-            }
+            var name = _body.ReadStringWithLengthPrefix();
+            var value = _body.ReadStringWithLengthPrefix();

-            var targetPosition = _body.Offset + userPropertiesLength;
-            while (_body.Offset < targetPosition)
-            {
-                var name = _body.ReadStringWithLengthPrefix();
-                var value = _body.ReadStringWithLengthPrefix();
-
-                userProperties.Add(new MqttUserProperty(name, value));
-            }
+            userProperties.Add(new MqttUserProperty(name, value));
        }

        public string ReadReasonString()
@@ -78,17 +67,17 @@ namespace MQTTnet.Formatter.V5
            return _body.ReadWithLengthPrefix();
        }

-        public bool? ReadRetainAvailable()
+        public bool ReadRetainAvailable()
        {
            return _body.ReadBoolean();
        }

-        public uint? ReadSessionExpiryInterval()
+        public uint ReadSessionExpiryInterval()
        {
            return _body.ReadFourByteInteger();
        }

-        public ushort? ReadReceiveMaximum()
+        public ushort ReadReceiveMaximum()
        {
            return _body.ReadTwoByteInteger();
        }
@@ -103,17 +92,17 @@ namespace MQTTnet.Formatter.V5
            return _body.ReadStringWithLengthPrefix();
        }

-        public ushort? ReadTopicAliasMaximum()
+        public ushort ReadTopicAliasMaximum()
        {
            return _body.ReadTwoByteInteger();
        }

-        public uint? ReadMaximumPacketSize()
+        public uint ReadMaximumPacketSize()
        {
            return _body.ReadFourByteInteger();
        }

-        public ushort? ReadServerKeepAlive()
+        public ushort ReadServerKeepAlive()
        {
            return _body.ReadTwoByteInteger();
        }
@@ -123,22 +112,22 @@ namespace MQTTnet.Formatter.V5
            return _body.ReadStringWithLengthPrefix();
        }

-        public bool? ReadSharedSubscriptionAvailable()
+        public bool ReadSharedSubscriptionAvailable()
        {
            return _body.ReadBoolean();
        }

-        public bool? ReadSubscriptionIdentifiersAvailable()
+        public bool ReadSubscriptionIdentifiersAvailable()
        {
            return _body.ReadBoolean();
        }

-        public bool? ReadWildcardSubscriptionAvailable()
+        public bool ReadWildcardSubscriptionAvailable()
        {
            return _body.ReadBoolean();
        }

-        public uint? ReadSubscriptionIdentifier()
+        public uint ReadSubscriptionIdentifier()
        {
            return _body.ReadVariableLengthInteger();
        }
@@ -148,12 +137,12 @@ namespace MQTTnet.Formatter.V5
            return (MqttPayloadFormatIndicator)_body.ReadByte();
        }

-        public uint? ReadMessageExpiryInterval()
+        public uint ReadMessageExpiryInterval()
        {
            return _body.ReadFourByteInteger();
        }

-        public ushort? ReadTopicAlias()
+        public ushort ReadTopicAlias()
        {
            return _body.ReadTwoByteInteger();
        }
@@ -173,17 +162,17 @@ namespace MQTTnet.Formatter.V5
            return _body.ReadStringWithLengthPrefix();
        }

-        public uint? ReadWillDelayInterval()
+        public uint ReadWillDelayInterval()
        {
            return _body.ReadFourByteInteger();
        }

-        public bool? RequestResponseInformation()
+        public bool RequestResponseInformation()
        {
            return _body.ReadBoolean();
        }

-        public bool? RequestProblemInformation()
+        public bool RequestProblemInformation()
        {
            return _body.ReadBoolean();
        }
@@ -19,16 +19,12 @@ namespace MQTTnet.Formatter.V5
                return;
            }

-            var propertyWriter = new MqttPacketWriter();
            foreach (var property in userProperties)
            {
-                propertyWriter.WriteWithLengthPrefix(property.Name);
-                propertyWriter.WriteWithLengthPrefix(property.Value);
+                _packetWriter.Write((byte)MqttPropertyId.UserProperty);
+                _packetWriter.WriteWithLengthPrefix(property.Name);
+                _packetWriter.WriteWithLengthPrefix(property.Value);
            }
-
-            _packetWriter.Write((byte)MqttPropertyId.UserProperty);
-            _packetWriter.WriteVariableLengthInteger((uint)propertyWriter.Length);
-            _packetWriter.Write(propertyWriter);
        }

        public void WriteCorrelationData(byte[] value)
@@ -66,7 +62,7 @@ namespace MQTTnet.Formatter.V5
            Write(MqttPropertyId.AuthenticationMethod, value);
        }

-        public void WriteToPacket(IMqttPacketWriter packetWriter)
+        public void WriteTo(IMqttPacketWriter packetWriter)
        {
            if (packetWriter == null) throw new ArgumentNullException(nameof(packetWriter));

@@ -84,6 +80,19 @@ namespace MQTTnet.Formatter.V5
            WriteAsVariableLengthInteger(MqttPropertyId.SubscriptionIdentifier, value);
        }

+        public void WriteSubscriptionIdentifiers(IEnumerable<uint> value)
+        {
+            if (value == null)
+            {
+                return;
+            }
+
+            foreach (var subscriptionIdentifier in value)
+            {
+                WriteAsVariableLengthInteger(MqttPropertyId.SubscriptionIdentifier, subscriptionIdentifier);
+            }
+        }
+
        public void WriteTopicAlias(ushort? value)
        {
            Write(MqttPropertyId.TopicAlias, value);
@@ -121,7 +130,7 @@ namespace MQTTnet.Formatter.V5

        public void WriteReceiveMaximum(ushort? value)
        {
-            Write(MqttPropertyId.RequestResponseInformation, value);
+            Write(MqttPropertyId.ReceiveMaximum, value);
        }

        public void WriteMaximumPacketSize(uint? value)
@@ -136,7 +145,7 @@ namespace MQTTnet.Formatter.V5

        public void WriteAssignedClientIdentifier(string value)
        {
-            Write(MqttPropertyId.AssignedClientIdentifer, value);
+            Write(MqttPropertyId.AssignedClientIdentifier, value);
        }

        public void WriteTopicAliasMaximum(ushort? value)
@@ -180,6 +189,17 @@ namespace MQTTnet.Formatter.V5
            _packetWriter.Write(value.Value ? (byte)0x1 : (byte)0x0);
        }

+        private void Write(MqttPropertyId id, byte? value)
+        {
+            if (!value.HasValue)
+            {
+                return;
+            }
+
+            _packetWriter.Write((byte)id);
+            _packetWriter.Write(value.Value);
+        }
+
        private void Write(MqttPropertyId id, ushort? value)
        {
            if (!value.HasValue)
@@ -5,6 +5,7 @@ using System.IO;
 using System.Linq;
 using System.Runtime.InteropServices.WindowsRuntime;
 using System.Security.Authentication;
+using System.Security.Cryptography.X509Certificates;
 using System.Threading;
 using System.Threading.Tasks;
 using Windows.Networking;
@@ -31,7 +32,7 @@ namespace MQTTnet.Implementations
            _bufferSize = _options.BufferSize;
        }

-        public MqttTcpChannel(StreamSocket socket, IMqttServerOptions serverOptions)
+        public MqttTcpChannel(StreamSocket socket, X509Certificate2 clientCertificate, IMqttServerOptions serverOptions)
        {
            _socket = socket ?? throw new ArgumentNullException(nameof(socket));
            _bufferSize = serverOptions.DefaultEndpointOptions.BufferSize;
@@ -39,6 +40,7 @@ namespace MQTTnet.Implementations
            CreateStreams();

            IsSecureConnection = socket.Information.ProtectionLevel >= SocketProtectionLevel.Tls12;
+            ClientCertificate = clientCertificate;

            Endpoint = _socket.Information.RemoteAddress + ":" + _socket.Information.RemotePort;
        }
@@ -49,6 +51,8 @@ namespace MQTTnet.Implementations

        public bool IsSecureConnection { get; }

+        public X509Certificate2 ClientCertificate { get; }
+
        public async Task ConnectAsync(CancellationToken cancellationToken)
        {
            if (_socket == null)
@@ -28,18 +28,22 @@ namespace MQTTnet.Implementations
            IsSecureConnection = clientOptions.ChannelOptions?.TlsOptions?.UseTls == true;
        }

-        public MqttTcpChannel(Stream stream, string endpoint)
+        public MqttTcpChannel(Stream stream, string endpoint, X509Certificate2 clientCertificate)
        {
            _stream = stream ?? throw new ArgumentNullException(nameof(stream));

-            IsSecureConnection = stream is SslStream;
            Endpoint = endpoint;
+
+            IsSecureConnection = stream is SslStream;
+            ClientCertificate = clientCertificate;
        }

        public string Endpoint { get; private set; }

        public bool IsSecureConnection { get; }

+        public X509Certificate2 ClientCertificate { get; }
+
        public async Task ConnectAsync(CancellationToken cancellationToken)
        {
            Socket socket;
@@ -55,9 +59,16 @@ namespace MQTTnet.Implementations

            socket.ReceiveBufferSize = _options.BufferSize;
            socket.SendBufferSize = _options.BufferSize;
-            socket.DualMode = _options.DualMode;
            socket.NoDelay = _options.NoDelay;

+            if (_options.DualMode.HasValue)
+            {
+                // It is important to avoid setting the flag if no specific value is set by the user
+                // because on IPv4 only networks the setter will always throw an exception. Regardless
+                // of the actual value.
+                socket.DualMode = _options.DualMode.Value;
+            }
+            
            // Workaround for: workaround for https://github.com/dotnet/corefx/issues/24430
            using (cancellationToken.Register(() => socket.Dispose()))
            {
@@ -73,9 +84,9 @@ namespace MQTTnet.Implementations
            if (_options.TlsOptions.UseTls)
            {
                var sslStream = new SslStream(networkStream, false, InternalUserCertificateValidationCallback);
-                await sslStream.AuthenticateAsClientAsync(_options.Server, LoadCertificates(), _options.TlsOptions.SslProtocol, _options.TlsOptions.IgnoreCertificateRevocationErrors).ConfigureAwait(false);
-
                _stream = sslStream;
+
+                await sslStream.AuthenticateAsClientAsync(_options.Server, LoadCertificates(), _options.TlsOptions.SslProtocol, _options.TlsOptions.IgnoreCertificateRevocationErrors).ConfigureAwait(false);                
            }
            else
            {
@@ -1,11 +1,13 @@
 #if WINDOWS_UWP
-using System;
-using System.Threading.Tasks;
 using Windows.Networking.Sockets;
 using MQTTnet.Adapter;
 using MQTTnet.Diagnostics;
 using MQTTnet.Formatter;
 using MQTTnet.Server;
+using System;
+using System.Runtime.InteropServices.WindowsRuntime;
+using System.Security.Cryptography.X509Certificates;
+using System.Threading.Tasks;

 namespace MQTTnet.Implementations
 {
@@ -73,7 +75,21 @@ namespace MQTTnet.Implementations
                var clientHandler = ClientHandler;
                if (clientHandler != null)
                {
-                    using (var clientAdapter = new MqttChannelAdapter(new MqttTcpChannel(args.Socket, _options), new MqttPacketFormatterAdapter(), _logger))
+                    X509Certificate2 clientCertificate = null;
+
+                    if (args.Socket.Control.ClientCertificate != null)
+                    {
+                        try
+                        {
+                            clientCertificate = new X509Certificate2(args.Socket.Control.ClientCertificate.GetCertificateBlob().ToArray());
+                        }
+                        catch (Exception exception)
+                        {
+                            _logger.Warning(exception, "Unable to convert UWP certificate to X509Certificate2.");
+                        }
+                    }
+                    
+                    using (var clientAdapter = new MqttChannelAdapter(new MqttTcpChannel(args.Socket, clientCertificate, _options), new MqttPacketFormatterAdapter(), _logger))
                    {
                        await clientHandler(clientAdapter).ConfigureAwait(false);
                    }
@@ -28,6 +28,8 @@ namespace MQTTnet.Implementations

        public Func<IMqttChannelAdapter, Task> ClientHandler { get; set; }

+        public bool TreatSocketOpeningErrorAsWarning { get; set; }
+
        public Task StartAsync(IMqttServerOptions options)
        {
            if (_cancellationTokenSource != null) throw new InvalidOperationException("Server is already started.");
@@ -36,7 +38,7 @@ namespace MQTTnet.Implementations

            if (options.DefaultEndpointOptions.IsEnabled)
            {
-                RegisterListeners(options.DefaultEndpointOptions, null);
+                RegisterListeners(options.DefaultEndpointOptions, null, _cancellationTokenSource.Token);
            }

            if (options.TlsEndpointOptions.IsEnabled)
@@ -46,13 +48,13 @@ namespace MQTTnet.Implementations
                    throw new ArgumentException("TLS certificate is not set.");
                }

-                var tlsCertificate = new X509Certificate2(options.TlsEndpointOptions.Certificate);
+                var tlsCertificate = new X509Certificate2(options.TlsEndpointOptions.Certificate, options.TlsEndpointOptions.CertificateCredentials.Password);
                if (!tlsCertificate.HasPrivateKey)
                {
                    throw new InvalidOperationException("The certificate for TLS encryption must contain the private key.");
                }

-                RegisterListeners(options.TlsEndpointOptions, tlsCertificate);
+                RegisterListeners(options.TlsEndpointOptions, tlsCertificate, _cancellationTokenSource.Token);
            }

            return Task.FromResult(0);
@@ -78,7 +80,7 @@ namespace MQTTnet.Implementations
            _listeners.Clear();
        }

-        private void RegisterListeners(MqttServerTcpEndpointBaseOptions options, X509Certificate2 tlsCertificate)
+        private void RegisterListeners(MqttServerTcpEndpointBaseOptions options, X509Certificate2 tlsCertificate, CancellationToken cancellationToken)
        {
            if (!options.BoundInterNetworkAddress.Equals(IPAddress.None))
            {
@@ -86,14 +88,15 @@ namespace MQTTnet.Implementations
                    AddressFamily.InterNetwork,
                    options,
                    tlsCertificate,
-                    _cancellationTokenSource.Token,
                    _logger)
                {
                    ClientHandler = OnClientAcceptedAsync
                };

-                listenerV4.Start();
-                _listeners.Add(listenerV4);
+                if (listenerV4.Start(TreatSocketOpeningErrorAsWarning, cancellationToken))
+                {
+                    _listeners.Add(listenerV4);
+                }
            }

            if (!options.BoundInterNetworkV6Address.Equals(IPAddress.None))
@@ -102,14 +105,15 @@ namespace MQTTnet.Implementations
                    AddressFamily.InterNetworkV6,
                    options,
                    tlsCertificate,
-                    _cancellationTokenSource.Token,
                    _logger)
                {
                    ClientHandler = OnClientAcceptedAsync
                };

-                listenerV6.Start();
-                _listeners.Add(listenerV6);
+                if (listenerV6.Start(TreatSocketOpeningErrorAsWarning, cancellationToken))
+                {
+                    _listeners.Add(listenerV6);
+                }
            }
        }

@@ -10,6 +10,7 @@ using System.Threading.Tasks;
 using MQTTnet.Adapter;
 using MQTTnet.Diagnostics;
 using MQTTnet.Formatter;
+using MQTTnet.Internal;
 using MQTTnet.Server;

 namespace MQTTnet.Implementations
@@ -17,24 +18,23 @@ namespace MQTTnet.Implementations
    public class MqttTcpServerListener : IDisposable
    {
        private readonly IMqttNetChildLogger _logger;
-        private readonly CancellationToken _cancellationToken;
        private readonly AddressFamily _addressFamily;
        private readonly MqttServerTcpEndpointBaseOptions _options;
        private readonly MqttServerTlsTcpEndpointOptions _tlsOptions;
        private readonly X509Certificate2 _tlsCertificate;
+
        private Socket _socket;
+        private IPEndPoint _localEndPoint;

        public MqttTcpServerListener(
            AddressFamily addressFamily,
            MqttServerTcpEndpointBaseOptions options,
            X509Certificate2 tlsCertificate,
-            CancellationToken cancellationToken,
            IMqttNetChildLogger logger)
        {
            _addressFamily = addressFamily;
            _options = options;
            _tlsCertificate = tlsCertificate;
-            _cancellationToken = cancellationToken;
            _logger = logger.CreateChildLogger(nameof(MqttTcpServerListener));

            if (_options is MqttServerTlsTcpEndpointOptions tlsOptions)
@@ -45,21 +45,51 @@ namespace MQTTnet.Implementations

        public Func<IMqttChannelAdapter, Task> ClientHandler { get; set; }

-        public void Start()
+        public bool Start(bool treatErrorsAsWarning, CancellationToken cancellationToken)
        {
-            var boundIp = _options.BoundInterNetworkAddress;
-            if (_addressFamily == AddressFamily.InterNetworkV6)
+            try
            {
-                boundIp = _options.BoundInterNetworkV6Address;
+                var boundIp = _options.BoundInterNetworkAddress;
+                if (_addressFamily == AddressFamily.InterNetworkV6)
+                {
+                    boundIp = _options.BoundInterNetworkV6Address;
+                }
+
+                _localEndPoint = new IPEndPoint(boundIp, _options.Port);
+
+                _logger.Info($"Starting TCP listener for {_localEndPoint} TLS={_tlsCertificate != null}.");
+
+                _socket = new Socket(_addressFamily, SocketType.Stream, ProtocolType.Tcp);
+
+                // Usage of socket options is described here: https://docs.microsoft.com/en-us/dotnet/api/system.net.sockets.socket.setsocketoption?view=netcore-2.2
+
+                if (_options.ReuseAddress)
+                {
+                    _socket.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.ReuseAddress, true);
+                }
+                
+                if (_options.NoDelay)
+                {
+                    _socket.SetSocketOption(SocketOptionLevel.Tcp, SocketOptionName.NoDelay, true);
+                }
+                
+                _socket.Bind(_localEndPoint);
+                _socket.Listen(_options.ConnectionBacklog);
+
+                Task.Run(() => AcceptClientConnectionsAsync(cancellationToken), cancellationToken).Forget(_logger);
+
+                return true;
            }
+            catch (Exception exception)
+            {
+                if (!treatErrorsAsWarning)
+                {
+                    throw;
+                }

-            _socket = new Socket(_addressFamily, SocketType.Stream, ProtocolType.Tcp);
-            _socket.Bind(new IPEndPoint(boundIp, _options.Port));
-
-            _logger.Info($"Starting TCP listener for {_socket.LocalEndPoint} TLS={_tlsCertificate != null}.");
-
-            _socket.Listen(_options.ConnectionBacklog);
-            Task.Run(() => AcceptClientConnectionsAsync(_cancellationToken), _cancellationToken);
+                _logger.Warning(exception,"Error while creating listener socket for local end point '{0}'.", _localEndPoint);
+                return false;
+            }
        }

        public void Dispose()
@@ -82,13 +112,29 @@ namespace MQTTnet.Implementations
 #else
                    var clientSocket = await _socket.AcceptAsync().ConfigureAwait(false);
 #endif
-#pragma warning disable 4014
-                    Task.Run(() => TryHandleClientConnectionAsync(clientSocket), cancellationToken);
-#pragma warning restore 4014
+
+                    if (clientSocket == null)
+                    {
+                        continue;
+                    }
+
+                    Task.Run(() => TryHandleClientConnectionAsync(clientSocket), cancellationToken).Forget(_logger);
+                }
+                catch (OperationCanceledException)
+                {  
                }
                catch (Exception exception)
                {
-                    _logger.Error(exception, $"Error while accepting connection at TCP listener {_socket.LocalEndPoint} TLS={_tlsCertificate != null}.");
+                    if (exception is SocketException socketException)
+                    {
+                        if (socketException.SocketErrorCode == SocketError.ConnectionAborted ||
+                            socketException.SocketErrorCode == SocketError.OperationAborted)
+                        {
+                            continue;
+                        }
+                    }
+                   
+                    _logger.Error(exception, $"Error while accepting connection at TCP listener {_localEndPoint} TLS={_tlsCertificate != null}.");
                    await Task.Delay(TimeSpan.FromSeconds(1), cancellationToken).ConfigureAwait(false);
                }
            }
@@ -105,24 +151,39 @@ namespace MQTTnet.Implementations

                _logger.Verbose("Client '{0}' accepted by TCP listener '{1}, {2}'.",
                    remoteEndPoint,
-                    _socket.LocalEndPoint,
+                    _localEndPoint,
                    _addressFamily == AddressFamily.InterNetwork ? "ipv4" : "ipv6");

                clientSocket.NoDelay = _options.NoDelay;

                stream = new NetworkStream(clientSocket, true);

+                X509Certificate2 clientCertificate = null;
+
                if (_tlsCertificate != null)
                {
-                    var sslStream = new SslStream(stream, false);
-                    await sslStream.AuthenticateAsServerAsync(_tlsCertificate, false, _tlsOptions.SslProtocol, false).ConfigureAwait(false);
+                    var sslStream = new SslStream(stream, false, _tlsOptions.RemoteCertificateValidationCallback);
+
+                    await sslStream.AuthenticateAsServerAsync(
+                        _tlsCertificate, 
+                        _tlsOptions.ClientCertificateRequired, 
+                        _tlsOptions.SslProtocol, 
+                        _tlsOptions.CheckCertificateRevocation).ConfigureAwait(false);
+
                    stream = sslStream;
+
+                    clientCertificate = sslStream.RemoteCertificate as X509Certificate2;
+
+                    if (clientCertificate == null && sslStream.RemoteCertificate != null)
+                    {
+                        clientCertificate = new X509Certificate2(sslStream.RemoteCertificate.Export(X509ContentType.Cert));
+                    }
                }

                var clientHandler = ClientHandler;
                if (clientHandler != null)
                {
-                    using (var clientAdapter = new MqttChannelAdapter(new MqttTcpChannel(stream, remoteEndPoint), new MqttPacketFormatterAdapter(), _logger))
+                    using (var clientAdapter = new MqttChannelAdapter(new MqttTcpChannel(stream, remoteEndPoint, clientCertificate), new MqttPacketFormatterAdapter(), _logger))
                    {
                        await clientHandler(clientAdapter).ConfigureAwait(false);
                    }
@@ -153,7 +214,7 @@ namespace MQTTnet.Implementations

                    _logger.Verbose("Client '{0}' disconnected at TCP listener '{1}, {2}'.",
                        remoteEndPoint,
-                        _socket.LocalEndPoint,
+                        _localEndPoint,
                        _addressFamily == AddressFamily.InterNetwork ? "ipv4" : "ipv6");
                }
                catch (Exception disposeException)
@@ -11,9 +11,9 @@ namespace MQTTnet.Implementations
 {
    public class MqttWebSocketChannel : IMqttChannel
    {
-        private readonly SemaphoreSlim _sendLock = new SemaphoreSlim(1, 1);
        private readonly MqttClientWebSocketOptions _options;

+        private SemaphoreSlim _sendLock = new SemaphoreSlim(1, 1);
        private WebSocket _webSocket;

        public MqttWebSocketChannel(MqttClientWebSocketOptions options)
@@ -21,18 +21,21 @@ namespace MQTTnet.Implementations
            _options = options ?? throw new ArgumentNullException(nameof(options));
        }

-        public MqttWebSocketChannel(WebSocket webSocket, string endpoint, bool isSecureConnection)
+        public MqttWebSocketChannel(WebSocket webSocket, string endpoint, bool isSecureConnection, X509Certificate2 clientCertificate)
        {
            _webSocket = webSocket ?? throw new ArgumentNullException(nameof(webSocket));

            Endpoint = endpoint;
            IsSecureConnection = isSecureConnection;
+            ClientCertificate = clientCertificate;
        }

        public string Endpoint { get; }

        public bool IsSecureConnection { get; private set; }

+        public X509Certificate2 ClientCertificate { get; private set; }
+
        public async Task ConnectAsync(CancellationToken cancellationToken)
        {
            var uri = _options.Uri;
@@ -114,9 +117,14 @@ namespace MQTTnet.Implementations

        public async Task WriteAsync(byte[] buffer, int offset, int count, CancellationToken cancellationToken)
        {
-            // This lock is required because the client will throw an exception if _SendAsync_ is 
+            // The lock is required because the client will throw an exception if _SendAsync_ is 
            // called from multiple threads at the same time. But this issue only happens with several
            // framework versions.
+            if (_sendLock == null)
+            {
+                return;
+            }
+
            await _sendLock.WaitAsync(cancellationToken).ConfigureAwait(false);
            try
            {
@@ -124,13 +132,14 @@ namespace MQTTnet.Implementations
            }
            finally
            {
-                _sendLock.Release();
+                _sendLock?.Release();
            }
        }

        public void Dispose()
        {
            _sendLock?.Dispose();
+            _sendLock = null;

            try
            {
--- a/Show More
+++ b/Show More
Author	SHA1	Message	Date
Christian Kratky	f54598c201	Merge branch 'develop'	2019-08-11 16:33:40 +02:00
Christian Kratky	2300e68fff	Add UnitTests for RPC.	2019-08-11 10:41:36 +02:00
Christian Kratky	6996824157	Merge branch 'master' into develop	2019-08-11 10:17:51 +02:00
Christian Kratky	524f695829	Update docs.	2019-08-09 22:21:42 +02:00
Christian	72faa067cc	Merge pull request #729 from cslutgen/clientcerts Add Server certificate password and client certificate builders	2019-08-09 22:07:26 +02:00
SeppPenner	01aa75471c	Updated description of issue templates.	2019-08-09 11:20:28 +02:00
HansM	048206eb1e	Fixed my spelling mistake from before.	2019-08-09 11:14:52 +02:00
HansM	ad5b0caa4d	Fixed spelling issue in feature request issue template.	2019-08-09 11:13:40 +02:00
HansM	0f14ddcf79	Updated bug report issue template.	2019-08-09 11:13:06 +02:00
Craig Lutgen	59d2a8e551	Changed server crentials property name from password to certificateCredentials	2019-08-08 13:35:14 -05:00
HansM	8607ceb3b7	Fixed feature request issue template.	2019-08-02 08:47:09 +02:00
HansM	b82e5a48a4	Fixed custom issue template.	2019-08-02 08:46:35 +02:00
HansM	30c5147c62	Fixed bug reports issue template.	2019-08-02 08:46:12 +02:00
Craig Lutgen	9d63500f95	Fix build issue with UWP	2019-07-31 13:27:33 -05:00
Craig Lutgen	a03bdc7616	Expose server certificate password and client certificate options to MqttServerOptionsBuilder	2019-07-31 13:04:03 -05:00
Christian Kratky	413daee551	Merge branch 'master' into develop	2019-07-30 20:35:48 +02:00
Christian Kratky	f3ea7008e5	Merge remote-tracking branch 'origin/develop' into develop	2019-07-30 20:35:39 +02:00
Christian Kratky	8bfbbd2b29	Refactoring.	2019-07-30 20:35:33 +02:00
Christian Kratky	ab8c7df0b9	Add unit Tests.	2019-07-30 20:35:22 +02:00
Christian Kratky	975eb60e90	Fix memory leak when SSL is not working properly.	2019-07-30 20:02:46 +02:00
Christian Kratky	6076151222	Update docs.	2019-07-30 20:01:57 +02:00
Christian Kratky	9cc96f1888	Refactor log messages.	2019-07-30 20:01:45 +02:00
HansM	7aa4d5159c	Fixed styling in feature request template.	2019-07-30 09:56:00 +02:00
Christian	9b021c4093	Update README.md	2019-07-27 09:57:36 +02:00
Christian	54c303369e	Update README.md	2019-07-27 09:56:59 +02:00
Christian	8f30042e49	Update README.md	2019-07-27 09:56:46 +02:00
Christian	4c33270d26	Merge pull request #718 from PaulFake/patch-3 Fixed AsyncLock::WaitAsync cancellation bug	2019-07-26 21:23:29 +02:00
Paul Fake	5c40577bec	Fixed AsyncLock::WaitAsync cancellation bug There isn't any code in MQTTnet that actually uses a cancellation token in WaitAsync, so this is more of a preventative thing than a bug fix. The original code just checks if the task was completed, not whether it was cancelled. If the process is cancelled immediately before the call to WaitAsync, it'll return as normal (https://referencesource.microsoft.com/#mscorlib/system/threading/SemaphoreSlim.cs,612) rather than throw a cancellation exception. This change will ensure we only return the releaser if the wait actually ran to completion rather than exited early due to cancellation. I've tested this, and it properly throws a cancellation exception later on.	2019-07-23 16:20:36 -04:00
Christian Kratky	3d404f9755	Fixed build.	2019-07-23 22:08:51 +02:00
Christian Kratky	1b5e0197e4	Update docs.	2019-07-23 21:56:14 +02:00
Christian	1dab729d84	Merge pull request #717 from PaulFake/patch-2 Storage queue drain test	2019-07-23 21:54:48 +02:00
Christian	3eac5bcaf3	Merge pull request #709 from PaulFake/patch-1 Fixed storage queue race condition	2019-07-23 21:54:21 +02:00
Paul Fake	8eb23f0f1d	Storage queue drain test It's a unit test to ensure the storage queue is drained.	2019-07-23 15:45:50 -04:00
Christian	1fd1a12fce	Merge pull request #715 from mseyock/change-icon Remove shadow and made text bold	2019-07-23 19:59:32 +02:00
Matthias Seyock	349d506b37	Remove shadow and made text bold	2019-07-23 16:03:18 +02:00
Christian	a981b05aa7	Merge pull request #712 from mseyock/change-icon fix typo in icon	2019-07-19 22:12:59 +02:00
Matthias Seyock	654f06d20d	fix typo in icon	2019-07-19 20:34:39 +02:00
Christian	c92cd10499	Merge pull request #711 from mseyock/change-icon Replace icon	2019-07-19 19:33:32 +02:00
Christian Kratky	ed06ea6bc9	Add version information to MQTTnet.Server.	2019-07-19 19:32:33 +02:00
Matthias Seyock	3d531151c6	Replace icon	2019-07-19 16:52:58 +02:00
Paul Fake	e1590fc0c8	Fixed storage queue race condition Sometimes, TryPublishQueuedMessageAsync would try to remove a message from the storage queue before PublishAsync added it to the storage queue, resulting in a message being stuck in the storage queue forever. Switched the message queue lock to an async lock and synchronized the storage queue updates with the message queue updates.	2019-07-17 16:55:56 -04:00
Christian Kratky	dbb227406b	Added UnitTests.	2019-07-17 21:58:37 +02:00
Christian	b891e1d1f4	Update issue templates	2019-07-17 19:45:08 +02:00
Christian	1d697e3b87	Merge pull request #702 from rudacs/clientCertificate-is-null X509Certificate convert to X509Certificate2 in ClientCertificate	2019-07-15 19:18:03 +02:00
Rudá Cunha	128484c55a	X509Certificate convert to X509Certificate2 in ClientCertificate	2019-07-15 10:46:45 -03:00
Christian Kratky	ff22c34bb2	Add first classes for persisted session support.	2019-07-12 20:36:46 +02:00
Christian Kratky	e7ba3f76dc	Add options builder methods for remote certificate validation callback.	2019-07-11 23:03:56 +02:00
Christian	1ae3324581	Merge pull request #697 from rudacs/add-server-remove-validation-callback Add remote certificate validation callback on server	2019-07-11 22:56:36 +02:00
Rudá Cunha	ba8ce15ab4	Add remote certificate validation callback on server	2019-07-11 16:28:09 -03:00
Christian Kratky	87b4ce5185	Extend build and upload script to publish symbols as well.	2019-07-11 21:28:07 +02:00
Christian Kratky	4eb2b77138	Fix wrong NoDelay usage in server implementation.	2019-07-11 21:11:11 +02:00
Christian Kratky	70ee49f3c6	Merge remote-tracking branch 'origin/develop' into develop	2019-07-09 22:42:50 +02:00
Christian Kratky	f223a26748	Update docs.	2019-07-09 22:42:44 +02:00
Christian	4574fdc951	Merge pull request #693 from JanEggers/pr/fix691 fixed #691	2019-07-09 22:39:48 +02:00
Jan Eggers	4f66614cdd	fixed #691	2019-07-09 14:15:46 +02:00
Christian Kratky	6608172719	MQTTnet.Server: Extend messages API.	2019-07-07 21:26:07 +02:00
Christian Kratky	6c8db47e25	Remove dedicated values from contexts and only provide session items.	2019-07-05 18:28:18 +02:00
Christian Kratky	3eb5e82d10	Expose connect packet in application message interceptor and subscription interceptor.	2019-07-04 23:06:37 +02:00
Christian Kratky	8563230f9c	Update docs.	2019-07-04 20:38:01 +02:00
Christian Kratky	019f428f0a	MQTTnet.Server: Add HTTP API for publishing of messages.	2019-07-04 20:27:48 +02:00
Christian Kratky	1847af13d2	Merge branch 'develop'	2019-06-28 10:20:51 +02:00
Christian Kratky	8916df8d7b	Move ReuseAddress to server options.	2019-06-27 15:20:27 +02:00
Christian Kratky	f66da92299	Merge branch 'develop'	2019-06-27 10:02:59 +02:00
Christian Kratky	979df5f17e	Fix broken nuget builds.	2019-06-27 10:02:47 +02:00
Christian Kratky	d50c8153b2	Merge branch 'master' into develop	2019-06-26 11:42:44 +02:00
Christian Kratky	b3ab7a1069	Set socket options to allow reusing address.	2019-06-24 13:46:51 +02:00
Christian Kratky	6af58ad90d	Fix MQTTnet.Server startup colors.	2019-06-24 13:46:27 +02:00
Christian	5c36a2d402	Merge pull request #671 from SeppPenner/patch-1 Added dependents and MIT license badge to the readme.	2019-06-24 13:40:26 +02:00
HansM	6df70cc5ed	Added dependents and MIT license badge to the readme.	2019-06-24 11:21:24 +02:00
Christian Kratky	d5b0893e90	Merge branch 'master' into develop	2019-06-23 21:50:42 +02:00
Christian Kratky	2ed8e55394	Fix upload script.	2019-06-23 21:46:06 +02:00
Christian Kratky	c5b6ca204d	Merge branch 'develop'	2019-06-23 21:37:35 +02:00
Christian Kratky	7a767c7d2f	Improve logging and exception handling when stopping the server.	2019-06-23 15:58:21 +02:00
Christian Kratky	dd96cf98a8	Make storage update for managed client async.	2019-06-23 15:57:48 +02:00
Christian Kratky	6ee3d1640f	Improve logging.	2019-06-23 15:57:12 +02:00
Christian Kratky	6f8272210c	Fix MQTTnet.Server app settings to allow external connections.	2019-06-23 15:39:50 +02:00
Christian Kratky	ce05cc9936	Fix MQTTnet.Server connection validation.	2019-06-23 15:39:07 +02:00
Christian Kratky	985c3084a8	Performance refactoring.	2019-06-23 12:37:55 +02:00
Christian Kratky	7b3be3a64f	Update docs.	2019-06-23 12:37:41 +02:00
Christian Kratky	c50fb740fc	Add UnitTests.	2019-06-23 12:37:33 +02:00
Christian Kratky	5895a73f85	Merge remote-tracking branch 'origin/develop' into develop	2019-06-23 11:32:11 +02:00
Christian Kratky	961a497798	Performance refactoring.	2019-06-23 11:32:09 +02:00
Christian	6a90864c44	Merge pull request #666 from vbBerni/develop fix Managed Client removes failed messages from message queue but not from storage manager	2019-06-23 11:30:31 +02:00
vbBerni	a9017b8795	handle storage manager null	2019-06-22 22:31:48 +02:00
vbBerni	f76e130283	fix for failed publishing messages get removed from the message queue but not from the storage manager	2019-06-19 16:33:54 +02:00
Christian Kratky	5a48b146b4	Merge branch 'master' into develop	2019-06-14 20:53:24 +02:00
Christian Kratky	1d1def3275	Remove nuget binary from repo.	2019-06-14 20:52:56 +02:00
Christian Kratky	bd75a2440e	Merge branch 'master' into develop	2019-06-14 20:43:33 +02:00
Christian Kratky	7a642802ed	Merge branch 'develop'	2019-06-14 20:43:18 +02:00
Christian Kratky	a8f8601bc5	Update docs.	2019-06-14 20:38:44 +02:00
Christian Kratky	0c7a5a992b	Expose more properties of the connection validator context in MQTTnet.Server. Migrate return code to reason code.	2019-06-14 20:38:07 +02:00
Christian Kratky	bd665c3d56	Expose more properties to connection validator context.	2019-06-14 20:37:06 +02:00
Christian Kratky	7e7b36aadf	Update docs.	2019-06-14 20:35:45 +02:00
Christian Kratky	a79c2484b3	Add MQTTnet.Server build for ARM.	2019-06-14 20:35:33 +02:00
Christian Kratky	e4e46f0094	Add comments.	2019-06-11 20:51:23 +02:00
Christian Kratky	5a4c735b85	Refactor code.	2019-06-11 20:50:11 +02:00
Christian Kratky	42516942ac	Update docs.	2019-06-09 14:14:40 +02:00
Christian Kratky	591ccfec29	Update authentication.	2019-06-09 14:13:50 +02:00
Christian Kratky	ffc1d950da	Add authorization for MQTTnet.Server	2019-06-09 00:10:26 +02:00
Christian Kratky	1c004ead6d	Add support for altering the TopicFilter in subscription interceptor.	2019-06-07 20:40:24 +02:00
Christian Kratky	b0ad6bda70	Add support for reset of connection statistics. Refactor keep alive monitor.	2019-06-06 21:12:32 +02:00
Christian Kratky	6262a16504	Add version to MQTTnet.Server.	2019-06-06 21:11:47 +02:00
Christian Kratky	0de683979d	Fix versions in build script.	2019-06-06 21:11:20 +02:00
Christian Kratky	0a6f564446	Add self contained builds in build script.	2019-06-06 20:26:41 +02:00
Christian Kratky	f0be3ef0cf	Add UnitTests.	2019-06-06 20:26:21 +02:00
Christian Kratky	f79eebdf64	Update docs.	2019-06-06 19:32:06 +02:00
Christian Kratky	c3c0dcf313	Execute disconnected handler in new task.	2019-06-06 19:32:00 +02:00
Christian Kratky	60c6074953	Expose client certificate at MQTT connection validator. Make DualMode optional.	2019-06-06 19:31:43 +02:00
Christian Kratky	2b9b22def6	Expose new options in server TLS options.	2019-06-06 19:27:25 +02:00
Christian Kratky	5cfb092449	Add UnitTests.	2019-06-06 19:26:43 +02:00
Christian Kratky	a450fc4e01	Add UnitTests.	2019-05-31 09:55:23 +02:00
Christian Kratky	ffe9c57ae8	Add overload for setting message payload.	2019-05-27 22:45:56 +02:00
Christian Kratky	0257e31910	Add UnitTests.	2019-05-27 20:06:51 +02:00
Christian Kratky	7fe5f521dc	Update docs.	2019-05-27 20:02:30 +02:00
Christian Kratky	2d03c267e4	Expose binary password to MqttConnectionValidatorContext.	2019-05-27 19:57:36 +02:00
Christian Kratky	ccfe67e6a6	Fix wrong password handling (string -> byte[])	2019-05-27 00:21:55 +02:00
Christian Kratky	98e17903ea	Merge remote-tracking branch 'origin/develop' into develop	2019-05-26 23:53:19 +02:00
Christian	c7d56a78f3	Merge pull request #628 from hezlog/develop Fixed MQTTnet.noUWP.sln build issue.	2019-05-26 23:53:07 +02:00
Christian Kratky	b491c74228	Merge remote-tracking branch 'origin/develop' into develop	2019-05-26 23:45:02 +02:00
Christian Kratky	a2414f48ca	Update Wiki samples.	2019-05-26 23:44:50 +02:00
Christian Kratky	396e0e1697	Add connected timestamp to connection status API.	2019-05-26 23:44:50 +02:00
Christian Kratky	01f6c959e1	Update publish profile.	2019-05-26 23:44:50 +02:00
Christian Kratky	f425d87562	Add publish profiles.	2019-05-26 23:44:50 +02:00
Christian Kratky	6614b23ab8	Add extension library for WebSocket4Net usage.	2019-05-26 23:44:50 +02:00
Christian Kratky	02c9133a1c	Update splash screen for MQTTnet.Server.	2019-05-26 23:44:50 +02:00
Christian Kratky	913afa3977	Add connack properties to authenticate result.	2019-05-26 23:44:50 +02:00
Christian Kratky	e068286f15	Add subscribe options builder.	2019-05-26 23:44:50 +02:00
Christian Kratky	373fe8c72c	Add connack properties to connect result.	2019-05-26 23:44:50 +02:00
Christian Kratky	396f040aae	Add support for extended authentication exchange.	2019-05-26 23:44:50 +02:00
Christian Kratky	c90b5f6fb2	Update UnitTests.	2019-05-26 23:44:50 +02:00
Christian Kratky	744b1b302b	Create MQTTnet.Server package from publish output instead build files.	2019-05-26 23:44:50 +02:00
Christian Kratky	78e504dc2c	Update Wiki samples.	2019-05-26 23:44:42 +02:00
Christian	79518d4a35	Merge pull request #634 from gitter-badger/gitter-badge Add a Gitter chat badge to README.md	2019-05-23 19:04:55 +02:00
The Gitter Badger	a50fb2a320	Add Gitter badge	2019-05-22 08:19:32 +00:00
hezlog	9fa9d22097	Fixed MQTTnet.noUWP.sln build issue.	2019-05-20 23:17:32 +08:00
Christian Kratky	e4351b73bd	Add connected timestamp to connection status API.	2019-05-19 22:23:10 +02:00
Christian Kratky	2d3fdd4faf	Update publish profile.	2019-05-18 20:51:19 +02:00
Christian Kratky	0a509fd685	Add publish profiles.	2019-05-18 20:50:29 +02:00
Christian Kratky	d1a17314ef	Add extension library for WebSocket4Net usage.	2019-05-18 09:48:44 +02:00
Christian Kratky	e96b66e9f8	Update splash screen for MQTTnet.Server.	2019-05-17 20:57:56 +02:00
Christian Kratky	80b05a8944	Add connack properties to authenticate result.	2019-05-17 20:57:40 +02:00
Christian Kratky	ab3df2ba65	Add subscribe options builder.	2019-05-17 20:57:15 +02:00
Christian Kratky	f169aaa79b	Add connack properties to connect result.	2019-05-17 20:56:58 +02:00
Christian Kratky	231001850a	Add support for extended authentication exchange.	2019-05-14 20:45:45 +02:00
Christian Kratky	6839970d41	Update UnitTests.	2019-05-14 20:40:58 +02:00
Christian Kratky	4df29be155	Create MQTTnet.Server package from publish output instead build files.	2019-05-14 20:40:44 +02:00
Christian Kratky	c5cfede231	Merge branch 'master' into develop	2019-05-13 07:25:56 +02:00
Christian Kratky	c22b6033e3	Accept multiple SubscriptionIdentifiers for PUBLISH packets.	2019-05-12 17:26:36 +02:00
Christian Kratky	27476a9194	Merge remote-tracking branch 'origin/master'	2019-05-12 00:18:54 +02:00
Christian Kratky	12973a4179	Fix issues in MQTTv5 packet encoding and decoding.	2019-05-12 00:18:48 +02:00
Christian	01b437dc08	Set theme jekyll-theme-hacker	2019-05-11 09:50:41 +02:00
				`@@ -1 +0,0 @@`
				[{"Topic":"a","Payload":"YWFzYXNhc2E=","QualityOfServiceLevel":0,"Retain":true,"UserProperties":[],"ContentType":null,"ResponseTopic":null,"PayloadFormatIndicator":null,"MessageExpiryInterval":null,"TopicAlias":null,"CorrelationData":null,"SubscriptionIdentifier":null},{"Topic":"fgdfgd","Payload":"YWFzYXNhc2E=","QualityOfServiceLevel":0,"Retain":true,"UserProperties":[],"ContentType":null,"ResponseTopic":null,"PayloadFormatIndicator":null,"MessageExpiryInterval":null,"TopicAlias":null,"CorrelationData":null,"SubscriptionIdentifier":null}]