.NET Core service worker DI example (#951)

* Added example source code

* Fix namespace name

* Added example source code

* Fix namespace name

* Fix sln file

* Update Program.cs

* Updated IKubernetes DI registration

examples/webApiDependencyInjection/Program.cs

@@ -6,7 +6,7 @@ var builder = WebApplication.CreateBuilder(args);
 var kubernetesClientConfig = KubernetesClientConfiguration.BuildDefaultConfig();
 
 // Register Kubernetes client interface as sigleton
-builder.Services.AddSingleton<IKubernetes>(new Kubernetes(kubernetesClientConfig));
+builder.Services.AddSingleton<IKubernetes>(_ => new Kubernetes(kubernetesClientConfig));
 
 // Add services to the container.
 builder.Services.AddEndpointsApiExplorer();

examples/workerServiceDependencyInjection/Program.cs

@@ -0,0 +1,17 @@
+using k8s;
+using workerServiceDependencyInjection;
+
+IHost host = Host.CreateDefaultBuilder(args)
+    .ConfigureServices(services =>
+    {
+        // Load kubernetes configuration
+        var kubernetesClientConfig = KubernetesClientConfiguration.BuildDefaultConfig();
+
+        // Register Kubernetes client interface as sigleton
+        services.AddSingleton<IKubernetes>(_ => new Kubernetes(kubernetesClientConfig));
+
+        services.AddHostedService<Worker>();
+    })
+    .Build();
+
+await host.RunAsync();

examples/workerServiceDependencyInjection/Worker.cs

@@ -0,0 +1,40 @@
+using k8s;
+
+namespace workerServiceDependencyInjection
+{
+    public class Worker : BackgroundService
+    {
+        private readonly ILogger<Worker> logger;
+        private readonly IKubernetes kubernetesClient;
+
+        /// <summary>
+        /// Inject in the constructor the IKubernetes interface.
+        /// </summary>
+        /// <param name="logger"></param>
+        /// <param name="kubernetesClient"></param>
+        public Worker(ILogger<Worker> logger, IKubernetes kubernetesClient)
+        {
+            this.logger = logger;
+            this.kubernetesClient = kubernetesClient;
+        }
+
+        protected override async Task ExecuteAsync(CancellationToken stoppingToken)
+        {
+            while (!stoppingToken.IsCancellationRequested)
+            {
+                logger.LogInformation("Worker running at: {time}", DateTimeOffset.Now);
+
+                // Read the list of pods contained in default namespace
+                var podList = kubernetesClient.CoreV1.ListNamespacedPod("default");
+
+                // Print pods names
+                foreach (var pod in podList.Items)
+                {
+                    Console.WriteLine(pod.Metadata.Name);
+                }
+
+                await Task.Delay(1000, stoppingToken);
+            }
+        }
+    }
+}

examples/workerServiceDependencyInjection/appsettings.Development.json

@@ -0,0 +1,8 @@
+{
+  "Logging": {
+    "LogLevel": {
+      "Default": "Information",
+      "Microsoft.Hosting.Lifetime": "Information"
+    }
+  }
+}

examples/workerServiceDependencyInjection/appsettings.json

@@ -0,0 +1,8 @@
+{
+  "Logging": {
+    "LogLevel": {
+      "Default": "Information",
+      "Microsoft.Hosting.Lifetime": "Information"
+    }
+  }
+}

examples/workerServiceDependencyInjection/workerServiceDependencyInjection.csproj

@@ -0,0 +1,11 @@
+<Project Sdk="Microsoft.NET.Sdk.Worker">
+
+  <PropertyGroup>
+    <Nullable>enable</Nullable>
+    <ImplicitUsings>enable</ImplicitUsings>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.Extensions.Hosting" Version="6.0.1" />
+  </ItemGroup>
+</Project>