URLs in a hosted service example

Author: andrewlock

urls-in-a-hosted-service/Program.cs

@@ -0,0 +1,58 @@
+using Microsoft.AspNetCore.Hosting.Server;
+using Microsoft.AspNetCore.Hosting.Server.Features;
+
+var builder = WebApplication.CreateBuilder(args);
+builder.Services.AddHostedService<TestHostedService>();
+var app = builder.Build();
+
+app.MapGet("/", () => "Hello World!");
+
+app.Run();
+
+public class TestHostedService: BackgroundService
+{
+    private readonly IServiceProvider _services;
+    private readonly IHostApplicationLifetime _lifetime;
+    public TestHostedService(IServiceProvider services, IHostApplicationLifetime lifetime)
+    {
+        _services = services;
+        _lifetime = lifetime;
+
+    }
+
+    protected override async Task ExecuteAsync(CancellationToken stoppingToken)
+    {
+        if (!await WaitForAppStartup(_lifetime, stoppingToken))
+        {
+            return;
+        }
+
+        PrintAddresses(_services);
+
+        _lifetime.StopApplication();
+    }
+
+    static async Task<bool> WaitForAppStartup(IHostApplicationLifetime lifetime, CancellationToken stoppingToken)
+    {
+        var startedSource = new TaskCompletionSource();
+        var cancelledSource = new TaskCompletionSource();
+        using var reg1 = lifetime.ApplicationStarted.Register(() => startedSource.SetResult());
+        using var reg2 = stoppingToken.Register(() => cancelledSource.SetResult());
+
+        Task completedTask = await Task.WhenAny(startedSource.Task, cancelledSource.Task).ConfigureAwait(false);
+
+        return completedTask == startedSource.Task;
+    }
+
+    void PrintAddresses(IServiceProvider services)
+    {
+        Console.WriteLine("Checking addresses...");
+        var server = services.GetRequiredService<IServer>();
+        var addressFeature = server.Features.Get<IServerAddressesFeature>();
+        foreach(var address in addressFeature!.Addresses)
+        {
+            Console.WriteLine("Listing on address: " + address);
+        }
+    }
+
+}

urls-in-a-hosted-service/Properties/launchSettings.json

@@ -0,0 +1,13 @@
+{
+  "profiles": {
+    "urls_in_a_hosted_service": {
+      "commandName": "Project",
+      "dotnetRunMessages": true,
+      "launchBrowser": true,
+      "applicationUrl": "https://[::1]:0;http://[::1]:0",
+      "environmentVariables": {
+        "ASPNETCORE_ENVIRONMENT": "Development"
+      }
+    },
+  }
+}

urls-in-a-hosted-service/appsettings.Development.json

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

urls-in-a-hosted-service/appsettings.json

@@ -0,0 +1,9 @@
+{
+  "Logging": {
+    "LogLevel": {
+      "Default": "Information",
+      "Microsoft.AspNetCore": "Warning"
+    }
+  },
+  "AllowedHosts": "*"
+}

urls-in-a-hosted-service/urls-in-a-hosted-service.csproj

@@ -0,0 +1,10 @@
+<Project Sdk="Microsoft.NET.Sdk.Web">
+
+  <PropertyGroup>
+    <TargetFramework>net6.0</TargetFramework>
+    <Nullable>enable</Nullable>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <RootNamespace>urls_in_a_hosted_service</RootNamespace>
+  </PropertyGroup>
+
+</Project>

urls-in-a-hosted-service/urls-in-a-hosted-service.sln

@@ -0,0 +1,22 @@
+
+Microsoft Visual Studio Solution File, Format Version 12.00
+# Visual Studio Version 16
+VisualStudioVersion = 16.0.30114.105
+MinimumVisualStudioVersion = 10.0.40219.1
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "urls-in-a-hosted-service", "urls-in-a-hosted-service.csproj", "{D16B9DA4-DBBE-4569-A695-58E7A97CCBBE}"
+EndProject
+Global
+	GlobalSection(SolutionConfigurationPlatforms) = preSolution
+		Debug|Any CPU = Debug|Any CPU
+		Release|Any CPU = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(SolutionProperties) = preSolution
+		HideSolutionNode = FALSE
+	EndGlobalSection
+	GlobalSection(ProjectConfigurationPlatforms) = postSolution
+		{D16B9DA4-DBBE-4569-A695-58E7A97CCBBE}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{D16B9DA4-DBBE-4569-A695-58E7A97CCBBE}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{D16B9DA4-DBBE-4569-A695-58E7A97CCBBE}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{D16B9DA4-DBBE-4569-A695-58E7A97CCBBE}.Release|Any CPU.Build.0 = Release|Any CPU
+	EndGlobalSection
+EndGlobal