Adding basic middleware sample

FunctionApp/FunctionApp.csproj

@@ -6,7 +6,7 @@
     <OutputType>Exe</OutputType>
     <_FunctionsSkipCleanOutput>true</_FunctionsSkipCleanOutput>
   </PropertyGroup>
-  <Target Name="CopyRuntimes" AfterTargets="AfterBuild"  Condition=" '$(OS)' == 'UNIX' ">
+  <Target Name="CopyRuntimes" AfterTargets="AfterBuild" Condition=" '$(OS)' == 'UNIX' ">
     <!-- To workaround a bug where the files aren't copied correctly for non-Windows platforms -->
     <Exec Command="rm -rf $(OutDir)bin/runtimes/* &amp;&amp; mkdir -p $(OutDir)bin/runtimes &amp;&amp; cp -R $(OutDir)runtimes/* $(OutDir)bin/runtimes/" />
   </Target>
@@ -17,7 +17,7 @@
     <PackageReference Include="Microsoft.Azure.WebJobs.Extensions.Http" Version="3.0.2" />
     <PackageReference Include="Microsoft.Azure.WebJobs.Extensions.Storage" Version="4.0.3" />
     <PackageReference Include="Microsoft.Azure.WebJobs.Script.ExtensionsMetadataGenerator" Version="1.2.0" />
-    <PackageReference Include="Microsoft.Azure.Functions.Worker.Sdk" Version="1.0.0-preview1" OutputItemType="Analyzer"/>
+    <PackageReference Include="Microsoft.Azure.Functions.Worker.Sdk" Version="1.0.0-preview1" OutputItemType="Analyzer" />
     <PackageReference Include="Microsoft.Azure.Functions.Worker" Version="1.0.0-preview1" />
     <PackageReference Include="Newtonsoft.Json" Version="12.0.3" />
     <PackageReference Include="System.Net.NameResolution" Version="4.3.0" />

FunctionApp/Middleware/ApplicationBuilderExtensions.cs

@@ -0,0 +1,30 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using Microsoft.Azure.Functions.Worker.Configuration;
+using Microsoft.Extensions.DependencyInjection;
+
+namespace FunctionApp.Middleware
+{
+    public static class ApplicationBuilderExtensions
+    {
+        public static IFunctionsWorkerApplicationBuilder UseSampleMiddleware(this IFunctionsWorkerApplicationBuilder builder)
+        {
+            builder.Services.AddSingleton<SampleMiddleware>();
+
+            builder.Use(next =>
+            {
+                return context =>
+                {
+                    var middleware = context.InstanceServices.GetRequiredService<SampleMiddleware>();
+
+                    return middleware.Invoke(context, next);
+                };
+            });
+
+            return builder;
+        }
+    }
+}

FunctionApp/Middleware/SampleMiddleware.cs

@@ -0,0 +1,14 @@
+using Microsoft.Azure.Functions.Worker.Pipeline;
+using System.Threading.Tasks;
+
+namespace FunctionApp
+{
+    public class SampleMiddleware
+    {
+        public Task Invoke(FunctionExecutionContext context, FunctionExecutionDelegate next)
+        {
+            context.Items.Add("Greeting", "Hello from our middleware");
+            return next(context);
+        }
+    }
+}

FunctionApp/Program.cs

@@ -4,6 +4,7 @@ using System.Diagnostics;
 using Microsoft.Extensions.Hosting;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Azure.Functions.Worker.Configuration;
+using FunctionApp.Middleware;
 
 namespace FunctionApp
 {
@@ -21,6 +22,7 @@ namespace FunctionApp
                 })
                 .ConfigureFunctionsWorker((c, b) =>
                 {
+                    b.UseSampleMiddleware();
                     b.UseFunctionExecutionMiddleware();
                 })
                 .ConfigureServices(s =>