Unable to resolve service: retarget net10.0, drop Swashbuckle, add string and HttpClient scenarios

dotnet-dependency-injection/FixUnableToResolveServiceIssue/FixUnableToResolveServiceIssue.Tests/Controllers/UserControllerIntegrationTest.cs

@@ -5,14 +5,22 @@
 
 namespace FixUnableToResolveServiceIssue.Tests.Controllers
 {
-    internal class UserControllerIntegrationTest
+    public class UserControllerIntegrationTest
     {
+        private readonly WebApplicationFactory<Program> _application;
         private readonly HttpClient _httpClient;
-        
+
         public UserControllerIntegrationTest()
         {
-            var application = new WebApplicationFactory<Program>();
-            _httpClient = application.CreateClient();
+            _application = new WebApplicationFactory<Program>();
+            _httpClient = _application.CreateClient();
+        }
+
+        [OneTimeTearDown]
+        public void OneTimeTearDown()
+        {
+            _httpClient.Dispose();
+            _application.Dispose();
         }
 
         [Test]

dotnet-dependency-injection/FixUnableToResolveServiceIssue/FixUnableToResolveServiceIssue.Tests/FixUnableToResolveServiceIssue.Tests.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>net7.0</TargetFramework>
+    <TargetFramework>net10.0</TargetFramework>
     <ImplicitUsings>enable</ImplicitUsings>
     <Nullable>enable</Nullable>
 
@@ -10,12 +10,12 @@
   </PropertyGroup>
 
   <ItemGroup>
-	  <PackageReference Include="Microsoft.AspNetCore.Mvc.Testing" Version="7.0.8" />
-	  <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.3.2" />
-    <PackageReference Include="NUnit" Version="3.13.3" />
-    <PackageReference Include="NUnit3TestAdapter" Version="4.3.0" />
-    <PackageReference Include="NUnit.Analyzers" Version="3.5.0" />
-    <PackageReference Include="coverlet.collector" Version="3.1.2" />
+	  <PackageReference Include="Microsoft.AspNetCore.Mvc.Testing" Version="10.0.12" />
+	  <PackageReference Include="Microsoft.NET.Test.Sdk" Version="18.10.1" />
+    <PackageReference Include="NUnit" Version="4.6.1" />
+    <PackageReference Include="NUnit3TestAdapter" Version="6.3.0" />
+    <PackageReference Include="NUnit.Analyzers" Version="4.15.0" />
+    <PackageReference Include="coverlet.collector" Version="10.0.1" />
   </ItemGroup>
 
   <ItemGroup>

dotnet-dependency-injection/FixUnableToResolveServiceIssue/FixUnableToResolveServiceIssue.Tests/Services/ServiceResolutionTest.cs

@@ -0,0 +1,56 @@
+using FixUnableToResolveServiceIssue.Services;
+using Microsoft.AspNetCore.Mvc.Testing;
+using Microsoft.Extensions.DependencyInjection;
+
+namespace FixUnableToResolveServiceIssue.Tests.Services
+{
+    public class ServiceResolutionTest
+    {
+        private WebApplicationFactory<Program> _factory = null!;
+
+        [OneTimeSetUp]
+        public void OneTimeSetUp()
+        {
+            _factory = new WebApplicationFactory<Program>();
+        }
+
+        [OneTimeTearDown]
+        public void OneTimeTearDown()
+        {
+            _factory.Dispose();
+        }
+
+        [Test]
+        public void WhenSmtpSettingsAreBoundToOptions_EmailServiceResolvesWithConfiguredValues()
+        {
+            //Arrange
+            using var scope = _factory.Services.CreateScope();
+
+            //Act
+            var emailService = scope.ServiceProvider.GetRequiredService<EmailService>();
+
+            //Assert
+            Assert.That(emailService.GetServerAddress(), Is.EqualTo("smtp.example.com:587"));
+        }
+
+        [Test]
+        public void WhenAddHttpClientIsRegistered_HttpClientTypesResolve()
+        {
+            //Arrange
+            using var scope = _factory.Services.CreateScope();
+            var provider = scope.ServiceProvider;
+
+            //Act
+            var httpClientFactory = provider.GetService<IHttpClientFactory>();
+            var httpClient = provider.GetService<HttpClient>();
+            var weatherClient = provider.GetService<WeatherClient>();
+
+            //Assert
+            Assert.That(httpClientFactory, Is.Not.Null);
+            Assert.That(httpClient, Is.Not.Null);
+            Assert.That(weatherClient, Is.Not.Null);
+            Assert.That(httpClientFactory!.CreateClient(nameof(WeatherClient)).BaseAddress,
+                Is.EqualTo(new Uri("https://api.example.com/")));
+        }
+    }
+}

dotnet-dependency-injection/FixUnableToResolveServiceIssue/FixUnableToResolveServiceIssue/FixUnableToResolveServiceIssue.csproj

@@ -1,14 +1,13 @@
 <Project Sdk="Microsoft.NET.Sdk.Web">
 
   <PropertyGroup>
-    <TargetFramework>net7.0</TargetFramework>
+    <TargetFramework>net10.0</TargetFramework>
     <Nullable>enable</Nullable>
     <ImplicitUsings>enable</ImplicitUsings>
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="Microsoft.AspNetCore.OpenApi" Version="7.0.4" />
-    <PackageReference Include="Swashbuckle.AspNetCore" Version="6.4.0" />
+    <PackageReference Include="Microsoft.AspNetCore.OpenApi" Version="10.0.12" />
   </ItemGroup>
 
 </Project>

dotnet-dependency-injection/FixUnableToResolveServiceIssue/FixUnableToResolveServiceIssue/Program.cs

@@ -1,24 +1,38 @@
 using FixUnableToResolveServiceIssue.Interfaces;
 using FixUnableToResolveServiceIssue.Services;
+using FixUnableToResolveServiceIssue.Settings;
 
 var builder = WebApplication.CreateBuilder(args);
 
 // Add services to the container.
 
 builder.Services.AddControllers();
-// Learn more about configuring Swagger/OpenAPI at https://aka.ms/aspnetcore/swashbuckle
-builder.Services.AddEndpointsApiExplorer();
-builder.Services.AddSwaggerGen();
+// Learn more about configuring OpenAPI at https://aka.ms/aspnet/openapi
+builder.Services.AddOpenApi();
 
-//Add this line to register the service as a singleton in the dependency injection container:
+//Add this line to register the service with a scoped lifetime in the dependency injection container:
 builder.Services.AddScoped<IUserService, UserService>();
+
+// A plain string cannot be resolved by type, so the SMTP values are bound to an options class
+// and EmailService asks for IOptions<SmtpSettings> instead:
+builder.Services.Configure<SmtpSettings>(builder.Configuration.GetSection("Smtp"));
+builder.Services.AddScoped<EmailService>();
+
+// Registers IHttpClientFactory and makes a plain HttpClient injectable:
+builder.Services.AddHttpClient();
+
+// Registers WeatherClient as a typed client with its own configured HttpClient:
+builder.Services.AddHttpClient<WeatherClient>(client =>
+{
+    client.BaseAddress = new Uri("https://api.example.com/");
+});
+
 var app = builder.Build();
 
 // Configure the HTTP request pipeline.
 if (app.Environment.IsDevelopment())
 {
-    app.UseSwagger();
-    app.UseSwaggerUI();
+    app.MapOpenApi();
 }
 
 app.UseHttpsRedirection();

dotnet-dependency-injection/FixUnableToResolveServiceIssue/FixUnableToResolveServiceIssue/Properties/launchSettings.json

@@ -13,7 +13,7 @@
       "commandName": "Project",
       "dotnetRunMessages": true,
       "launchBrowser": true,
-      "launchUrl": "swagger",
+      "launchUrl": "api/User",
       "applicationUrl": "https://localhost:7027;http://localhost:5073",
       "environmentVariables": {
         "ASPNETCORE_ENVIRONMENT": "Development"

dotnet-dependency-injection/FixUnableToResolveServiceIssue/FixUnableToResolveServiceIssue/Services/EmailService.cs

@@ -0,0 +1,20 @@
+using FixUnableToResolveServiceIssue.Settings;
+using Microsoft.Extensions.Options;
+
+namespace FixUnableToResolveServiceIssue.Services
+{
+    public class EmailService
+    {
+        private readonly SmtpSettings _settings;
+
+        // Asking for "string host" here instead would throw
+        // "Unable to resolve service for type 'System.String'", because the container
+        // cannot tell which string we mean. IOptions<SmtpSettings> is a type it can resolve.
+        public EmailService(IOptions<SmtpSettings> options)
+        {
+            _settings = options.Value;
+        }
+
+        public string GetServerAddress() => $"{_settings.Host}:{_settings.Port}";
+    }
+}

dotnet-dependency-injection/FixUnableToResolveServiceIssue/FixUnableToResolveServiceIssue/Services/WeatherClient.cs

@@ -0,0 +1,7 @@
+namespace FixUnableToResolveServiceIssue.Services
+{
+    public class WeatherClient(HttpClient httpClient)
+    {
+        public Task<string> GetForecastAsync() => httpClient.GetStringAsync("forecast");
+    }
+}

dotnet-dependency-injection/FixUnableToResolveServiceIssue/FixUnableToResolveServiceIssue/Settings/SmtpSettings.cs

@@ -0,0 +1,8 @@
+namespace FixUnableToResolveServiceIssue.Settings
+{
+    public class SmtpSettings
+    {
+        public string Host { get; set; } = string.Empty;
+        public int Port { get; set; }
+    }
+}

dotnet-dependency-injection/FixUnableToResolveServiceIssue/FixUnableToResolveServiceIssue/appsettings.json

@@ -5,5 +5,9 @@
       "Microsoft.AspNetCore": "Warning"
     }
   },
-  "AllowedHosts": "*"
+  "AllowedHosts": "*",
+  "Smtp": {
+    "Host": "smtp.example.com",
+    "Port": 587
+  }
 }