.

README.md

@@ -11,8 +11,13 @@
 ```csharp
 var builder = WebApplication.CreateBuilder(args);
 
+builder.Services.Configure<RouteHandlerOptions>(o => o.ThrowOnBadRequest = true);
+builder.Services.AddExceptionHandler<BadRequestExceptionHandler>();
 builder.Services.AddExceptionHandler<GlobalExceptionHandler>();
-builder.Services.AddProblemDetails();
+builder.Services.AddProblemDetails(options =>
+    options.CustomizeProblemDetails = context =>
+        context.ProblemDetails.Extensions["traceId"] =
+            Activity.Current?.Id ?? context.HttpContext.TraceIdentifier);
 
 var app = builder.Build();
 
@@ -23,7 +28,10 @@ app.UseExceptionHandler();
 * https://github.com/Carl-Hugo/FluentValidation.AspNetCore.Http
 * `dotnet add package ForEvolve.FluentValidation.AspNetCore.Http`
 ```csharp
+var root = app.MapGroup("/")
+              .AddFluentValidationFilter();
 
+root.MapPost(...)
 ```
 
 ## Swagger Request Exapmle 작성
@@ -116,3 +124,11 @@ For methods not supported 405
 Generic server error 500
 ```
 
+## HttpClient의 올바른 사용방법
+* https://devblogs.microsoft.com/dotnet/author/martintomka/
+* https://learn.microsoft.com/ko-kr/dotnet/core/resilience/http-resilience
+* `Microsoft.Extensions.Http.Resilience` 패키지 사용(암시적으로 polly를 사용함)
+* `Chaos Engineering`
+```
+
+```

src/WebApplicationMinimalApi8/ExceptionHandlers/BadRequestExceptionHandler.cs

@@ -0,0 +1,23 @@
+using Microsoft.AspNetCore.Diagnostics;
+using Microsoft.AspNetCore.Http.HttpResults;
+
+namespace WebApplicationMinimalApi8.ExceptionHandlers;
+
+public sealed class BadRequestExceptionHandler(ILogger<GlobalExceptionHandler> logger) : IExceptionHandler
+{
+    public async ValueTask<bool> TryHandleAsync(HttpContext httpContext, Exception exception, CancellationToken cancellationToken)
+    {
+        if (exception is BadHttpRequestException ex)
+        {
+            logger.LogError(exception, "Exception occurred: {Message}", exception.Message);
+
+            await Results.Problem(
+                title: exception.Message,
+                statusCode: StatusCodes.Status400BadRequest
+            ).ExecuteAsync(httpContext);
+
+            return true;
+        }
+        return false;
+    }
+}

src/WebApplicationMinimalApi8/Program.cs

@@ -27,21 +27,24 @@
     };
 });
 builder.Services.AddValidatorsFromAssemblyContaining<Program>();
+
 builder.AddFluentValidationEndpointFilter();
 
+
+builder.Services.AddHttpClient("echo", client =>
+{
+    client.BaseAddress = new("https://httpbin.org");
+});
+
 if (builder.Environment.IsEnvironment("Best"))
 {
+    builder.Services.Configure<RouteHandlerOptions>(o => o.ThrowOnBadRequest = true);
+    builder.Services.AddExceptionHandler<BadRequestExceptionHandler>();
     builder.Services.AddExceptionHandler<GlobalExceptionHandler>();
     builder.Services.AddProblemDetails(options =>
-        options.CustomizeProblemDetails = (context) =>
-    {
-        if (!context.ProblemDetails.Extensions.ContainsKey("traceId"))
-        {
-            string? traceId = Activity.Current?.Id ?? context.HttpContext.TraceIdentifier;
-            context.ProblemDetails.Extensions.Add(new KeyValuePair<string, object?>("traceId", traceId));
-        }
-    }
-);
+        options.CustomizeProblemDetails = context =>
+            context.ProblemDetails.Extensions["traceId"] =
+                Activity.Current?.Id ?? context.HttpContext.TraceIdentifier);
 }
 
 var app = builder.Build();
@@ -79,9 +82,9 @@
     .WithDescription("사람을 생성합니다.")
     .WithOpenApi();
 
-root.MapPut("/Persons", (PersonDto person) => Results.Created("/Persons/1", new
+root.MapPut("/Persons/{id}", (PersonDto person, int id) => Results.Ok(new
     {
-        Id = 1,
+        Id = id,
         person.Name,
         person.Age,
         person.Emails

src/WebApplicationMinimalApi8/WebApplicationMinimalApi8.csproj

@@ -11,6 +11,7 @@
     <PackageReference Include="FluentValidation.AspNetCore" Version="11.3.0" />
     <PackageReference Include="ForEvolve.FluentValidation.AspNetCore.Http" Version="1.0.26" />
     <PackageReference Include="Microsoft.AspNetCore.OpenApi" Version="8.0.2" />
+    <PackageReference Include="Microsoft.Extensions.Http.Resilience" Version="8.2.0" />
     <PackageReference Include="Swashbuckle.AspNetCore" Version="6.5.0" />
     <PackageReference Include="Swashbuckle.AspNetCore.Filters" Version="8.0.1" />
   </ItemGroup>