Code half: one API project owns domain, infrastructure, and health

Directory.Packages.props

@@ -20,12 +20,12 @@
     <PackageVersion Include="Microsoft.EntityFrameworkCore" Version="10.0.10" />
     <PackageVersion Include="Microsoft.EntityFrameworkCore.Design" Version="10.0.10" />
     <PackageVersion Include="Microsoft.EntityFrameworkCore.Relational" Version="10.0.10" />
+    <PackageVersion Include="Microsoft.Extensions.Diagnostics.HealthChecks.EntityFrameworkCore" Version="10.0.10" />
     <PackageVersion Include="Npgsql.EntityFrameworkCore.PostgreSQL" Version="10.0.3" />
     <PackageVersion Include="Swashbuckle.AspNetCore" Version="10.2.3" />
 
-    <!-- ServiceDefaults -->
+    <!-- Observability + outgoing HTTP -->
     <PackageVersion Include="Microsoft.Extensions.Http.Resilience" Version="10.8.0" />
-    <PackageVersion Include="Microsoft.Extensions.ServiceDiscovery" Version="10.8.0" />
     <PackageVersion Include="OpenTelemetry.Exporter.OpenTelemetryProtocol" Version="1.16.0" />
     <PackageVersion Include="OpenTelemetry.Extensions.Hosting" Version="1.16.0" />
     <PackageVersion Include="OpenTelemetry.Instrumentation.AspNetCore" Version="1.16.0" />

ProductReviews.slnx

@@ -2,11 +2,9 @@
   <Folder Name="/src/">
     <Project Path="src/ProductReviews.Api/ProductReviews.Api.csproj" />
     <Project Path="src/ProductReviews.AppHost/ProductReviews.AppHost.csproj" />
-    <Project Path="src/ProductReviews.Domain/ProductReviews.Domain.csproj" />
-    <Project Path="src/ProductReviews.ServiceDefaults/ProductReviews.ServiceDefaults.csproj" />
   </Folder>
   <Folder Name="/tests/">
     <Project Path="tests/ProductReviews.Api.IntegrationTests/ProductReviews.Api.IntegrationTests.csproj" />
-    <Project Path="tests/ProductReviews.Domain.Tests/ProductReviews.Domain.Tests.csproj" />
+    <Project Path="tests/ProductReviews.Api.UnitTests/ProductReviews.Api.UnitTests.csproj" />
   </Folder>
 </Solution>

src/ProductReviews.Api/Features/Catalog/CatalogContracts.cs

@@ -1,4 +1,3 @@
-using ProductReviews.Domain.Catalog;
 using StrongTypes;
 
 namespace ProductReviews.Api.Features.Catalog;

src/ProductReviews.Api/Features/Catalog/CatalogController.cs

@@ -1,7 +1,6 @@
 using Microsoft.AspNetCore.Authorization;
 using Microsoft.AspNetCore.Mvc;
 using ProductReviews.Api.Infrastructure;
-using ProductReviews.Domain.Catalog;
 using StrongTypes;
 
 namespace ProductReviews.Api.Features.Catalog;

src/ProductReviews.Domain/Catalog/GetCatalog.cs → src/ProductReviews.Api/Features/Catalog/GetCatalog.cs

@@ -1,7 +1,7 @@
 using Microsoft.EntityFrameworkCore;
-using ProductReviews.Domain.Persistence;
+using ProductReviews.Api.Persistence;
 
-namespace ProductReviews.Domain.Catalog;
+namespace ProductReviews.Api.Features.Catalog;
 
 public sealed class GetCatalogHandler(ReviewsDbContext dbContext)
 {

src/ProductReviews.Domain/Catalog/GetProductDetail.cs → src/ProductReviews.Api/Features/Catalog/GetProductDetail.cs

@@ -1,8 +1,8 @@
 using Microsoft.EntityFrameworkCore;
-using ProductReviews.Domain.Persistence;
+using ProductReviews.Api.Persistence;
 using StrongTypes;
 
-namespace ProductReviews.Domain.Catalog;
+namespace ProductReviews.Api.Features.Catalog;
 
 /// <summary>ViewerReviewId is the signed-in viewer's own review of this product, when they have one.</summary>
 public sealed record ProductDetailModel(Product Product, Guid? ViewerReviewId);

src/ProductReviews.Domain/Catalog/Product.cs → src/ProductReviews.Api/Features/Catalog/Product.cs

@@ -1,7 +1,7 @@
-using ProductReviews.Domain.Reviews;
+using ProductReviews.Api.Features.Reviews;
 using StrongTypes;
 
-namespace ProductReviews.Domain.Catalog;
+namespace ProductReviews.Api.Features.Catalog;
 
 public sealed class Product
 {

src/ProductReviews.Domain/Catalog/ProductWithReviews.cs → src/ProductReviews.Api/Features/Catalog/ProductWithReviews.cs

@@ -1,6 +1,6 @@
-using ProductReviews.Domain.Reviews;
+using ProductReviews.Api.Features.Reviews;
 
-namespace ProductReviews.Domain.Catalog;
+namespace ProductReviews.Api.Features.Catalog;
 
 /// <summary>Proof-of-loading aggregate: it can only be constructed with the product's
 /// reviews in hand, so code holding one never meets an unloaded navigation.

src/ProductReviews.Domain/Reviews/DeleteReview.cs → src/ProductReviews.Api/Features/Reviews/DeleteReview.cs

@@ -1,7 +1,7 @@
 using Microsoft.EntityFrameworkCore;
-using ProductReviews.Domain.Persistence;
+using ProductReviews.Api.Persistence;
 
-namespace ProductReviews.Domain.Reviews;
+namespace ProductReviews.Api.Features.Reviews;
 
 public enum DeleteReviewError
 {

src/ProductReviews.Domain/Reviews/EditReview.cs → src/ProductReviews.Api/Features/Reviews/EditReview.cs

@@ -1,8 +1,8 @@
 using Microsoft.EntityFrameworkCore;
-using ProductReviews.Domain.Persistence;
+using ProductReviews.Api.Persistence;
 using StrongTypes;
 
-namespace ProductReviews.Domain.Reviews;
+namespace ProductReviews.Api.Features.Reviews;
 
 public enum EditReviewError
 {

src/ProductReviews.Domain/Reviews/GetReviewsPage.cs → src/ProductReviews.Api/Features/Reviews/GetReviewsPage.cs

@@ -1,8 +1,8 @@
 using Microsoft.EntityFrameworkCore;
-using ProductReviews.Domain.Persistence;
+using ProductReviews.Api.Persistence;
 using StrongTypes;
 
-namespace ProductReviews.Domain.Reviews;
+namespace ProductReviews.Api.Features.Reviews;
 
 /// <summary>A review as one specific viewer sees it: with whether it is their own
 /// and which way they voted on it. Constructed only by the page query, so both

src/ProductReviews.Domain/Reviews/Rating.cs → src/ProductReviews.Api/Features/Reviews/Rating.cs

@@ -2,7 +2,7 @@
 using System.Text.Json.Serialization;
 using StrongTypes;
 
-namespace ProductReviews.Domain.Reviews;
+namespace ProductReviews.Api.Features.Reviews;
 
 /// <summary>A whole-star product rating, 1–5. Declared with the same three-line
 /// recipe the library's own numeric wrappers use: <c>[NumericWrapper]</c> plus a

src/ProductReviews.Domain/Reviews/Review.cs → src/ProductReviews.Api/Features/Reviews/Review.cs

@@ -1,7 +1,7 @@
-using ProductReviews.Domain.Votes;
+using ProductReviews.Api.Features.Votes;
 using StrongTypes;
 
-namespace ProductReviews.Domain.Reviews;
+namespace ProductReviews.Api.Features.Reviews;
 
 public sealed class Review
 {

src/ProductReviews.Domain/Reviews/ReviewAuthor.cs → src/ProductReviews.Api/Features/Reviews/ReviewAuthor.cs

@@ -1,8 +1,8 @@
 using StrongTypes;
 
-namespace ProductReviews.Domain.Reviews;
+namespace ProductReviews.Api.Features.Reviews;
 
 /// <summary>The acting reviewer, as the domain sees them: an opaque stable id
-/// (derived from the identity provider's subject, see ADR-0005) and the display
+/// (derived from the identity provider's subject, see ADR-0003) and the display
 /// name snapshotted onto anything they write.</summary>
 public sealed record ReviewAuthor(Guid AuthorId, NonEmptyString DisplayName);

src/ProductReviews.Api/Features/Reviews/ReviewContracts.cs

@@ -1,5 +1,4 @@
 using System.Text.Json.Serialization;
-using ProductReviews.Domain.Reviews;
 using StrongTypes;
 
 namespace ProductReviews.Api.Features.Reviews;

src/ProductReviews.Domain/Reviews/ReviewSort.cs → src/ProductReviews.Api/Features/Reviews/ReviewSort.cs

@@ -1,4 +1,4 @@
-namespace ProductReviews.Domain.Reviews;
+namespace ProductReviews.Api.Features.Reviews;
 
 public enum ReviewSort
 {

src/ProductReviews.Api/Features/Reviews/ReviewsController.cs

@@ -2,7 +2,6 @@
 using Microsoft.AspNetCore.Mvc;
 using Microsoft.AspNetCore.RateLimiting;
 using ProductReviews.Api.Infrastructure;
-using ProductReviews.Domain.Reviews;
 using StrongTypes;
 
 namespace ProductReviews.Api.Features.Reviews;

src/ProductReviews.Domain/Reviews/SubmitReview.cs → src/ProductReviews.Api/Features/Reviews/SubmitReview.cs

@@ -1,7 +1,7 @@
-using ProductReviews.Domain.Persistence;
+using ProductReviews.Api.Persistence;
 using StrongTypes;
 
-namespace ProductReviews.Domain.Reviews;
+namespace ProductReviews.Api.Features.Reviews;
 
 public enum SubmitReviewError
 {

src/ProductReviews.Domain/Votes/CastVote.cs → src/ProductReviews.Api/Features/Votes/CastVote.cs

@@ -1,7 +1,7 @@
-using ProductReviews.Domain.Persistence;
+using ProductReviews.Api.Persistence;
 using StrongTypes;
 
-namespace ProductReviews.Domain.Votes;
+namespace ProductReviews.Api.Features.Votes;
 
 public enum CastVoteError
 {

src/ProductReviews.Domain/Votes/RemoveVote.cs → src/ProductReviews.Api/Features/Votes/RemoveVote.cs

@@ -1,7 +1,7 @@
-using ProductReviews.Domain.Persistence;
+using ProductReviews.Api.Persistence;
 using StrongTypes;
 
-namespace ProductReviews.Domain.Votes;
+namespace ProductReviews.Api.Features.Votes;
 
 public enum RemoveVoteError
 {

src/ProductReviews.Domain/Votes/ReviewVote.cs → src/ProductReviews.Api/Features/Votes/ReviewVote.cs

@@ -1,4 +1,4 @@
-namespace ProductReviews.Domain.Votes;
+namespace ProductReviews.Api.Features.Votes;
 
 /// <summary>One reviewer's helpful/not-helpful verdict on one review.
 /// The composite key (ReviewId, VoterId) makes "one vote per reviewer per review" structural.</summary>

src/ProductReviews.Domain/Votes/ReviewWithVotes.cs → src/ProductReviews.Api/Features/Votes/ReviewWithVotes.cs

@@ -1,6 +1,6 @@
-using ProductReviews.Domain.Reviews;
+using ProductReviews.Api.Features.Reviews;
 
-namespace ProductReviews.Domain.Votes;
+namespace ProductReviews.Api.Features.Votes;
 
 /// <summary>Proof-of-loading aggregate: a review together with all its votes, so the
 /// helpfulness score can be recomputed without trusting a lazily-loaded navigation.

src/ProductReviews.Api/Features/Votes/VoteContracts.cs

@@ -1,4 +1,3 @@
-using ProductReviews.Domain.Votes;
 
 namespace ProductReviews.Api.Features.Votes;
 

src/ProductReviews.Domain/Votes/VoteSummary.cs → src/ProductReviews.Api/Features/Votes/VoteSummary.cs

@@ -1,4 +1,4 @@
-namespace ProductReviews.Domain.Votes;
+namespace ProductReviews.Api.Features.Votes;
 
 /// <summary>The state a voter sees after a vote operation: the review's recomputed
 /// score and their own current vote (null = no vote).</summary>

src/ProductReviews.Api/Features/Votes/VotesController.cs

@@ -2,7 +2,6 @@
 using Microsoft.AspNetCore.Mvc;
 using Microsoft.AspNetCore.RateLimiting;
 using ProductReviews.Api.Infrastructure;
-using ProductReviews.Domain.Votes;
 using StrongTypes;
 
 namespace ProductReviews.Api.Features.Votes;

src/ProductReviews.Api/Infrastructure/AppVersion.cs

@@ -0,0 +1,18 @@
+using System.Reflection;
+
+namespace ProductReviews.Api.Infrastructure;
+
+public static class AppVersion
+{
+    // The SDK embeds the git commit as the SourceRevisionId ("<version>+<sha>") when
+    // building from a checkout; a deploy gate reads it back out of /health.
+    public static readonly string InformationalVersion =
+        Assembly.GetEntryAssembly()
+            ?.GetCustomAttribute<AssemblyInformationalVersionAttribute>()
+            ?.InformationalVersion ?? "unknown";
+
+    public static readonly string CommitHash =
+        InformationalVersion.Contains('+')
+            ? InformationalVersion[(InformationalVersion.IndexOf('+') + 1)..]
+            : InformationalVersion;
+}

src/ProductReviews.Api/Infrastructure/Authentication.cs

@@ -20,7 +20,8 @@ public static void Configure(WebApplicationBuilder builder)
         var audience = builder.Configuration["Oidc:Audience"];
 
         builder.Services.AddMemoryCache();
-        builder.Services.AddHttpClient(UserinfoClientName);
+        // Per-client resilience, not ConfigureHttpClientDefaults — nothing blanket-global.
+        builder.Services.AddHttpClient(UserinfoClientName).AddStandardResilienceHandler();
 
         builder.Services
             .AddAuthentication(JwtBearerDefaults.AuthenticationScheme)

src/ProductReviews.Api/Infrastructure/CommitHashHealthCheck.cs

@@ -0,0 +1,12 @@
+using Microsoft.Extensions.Diagnostics.HealthChecks;
+
+namespace ProductReviews.Api.Infrastructure;
+
+internal sealed class CommitHashHealthCheck : IHealthCheck
+{
+    public Task<HealthCheckResult> CheckHealthAsync(HealthCheckContext context, CancellationToken cancellationToken = default)
+        => Task.FromResult(new HealthCheckResult(HealthStatus.Healthy, data: new Dictionary<string, object>
+        {
+            ["commit"] = AppVersion.CommitHash,
+        }));
+}

src/ProductReviews.Api/Infrastructure/CurrentUser.cs

@@ -1,14 +1,14 @@
 using System.Security.Claims;
 using System.Security.Cryptography;
 using System.Text;
-using ProductReviews.Domain.Reviews;
+using ProductReviews.Api.Features.Reviews;
 using StrongTypes;
 
 namespace ProductReviews.Api.Infrastructure;
 
 /// <summary>Maps the authenticated principal to the domain's <see cref="ReviewAuthor"/>.
 /// AuthorId is the SHA-256 of the OIDC <c>sub</c> claim (first 16 bytes as a Guid), so the
-/// database stays Guid-keyed whatever shape the identity provider's ids have (ADR-0005).</summary>
+/// database stays Guid-keyed whatever shape the identity provider's ids have (ADR-0003).</summary>
 public static class CurrentUser
 {
     public static ReviewAuthor Author(this ClaimsPrincipal user)

src/ProductReviews.Domain/DomainServices.cs → src/ProductReviews.Api/Infrastructure/DomainServices.cs

@@ -1,10 +1,9 @@
-using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.DependencyInjection.Extensions;
-using ProductReviews.Domain.Catalog;
-using ProductReviews.Domain.Reviews;
-using ProductReviews.Domain.Votes;
+using ProductReviews.Api.Features.Catalog;
+using ProductReviews.Api.Features.Reviews;
+using ProductReviews.Api.Features.Votes;
 
-namespace ProductReviews.Domain;
+namespace ProductReviews.Api.Infrastructure;
 
 public static class DomainServices
 {

src/ProductReviews.Api/Infrastructure/ErrorHandling.cs

@@ -1,7 +1,7 @@
 namespace ProductReviews.Api.Infrastructure;
 
 /// <summary>Unhandled exceptions become RFC 7807 responses. Business failures never get
-/// here — they travel as Result error enums and are mapped by controllers (ADR-0003).</summary>
+/// here — they travel as Result error enums and are mapped by controllers (ADR-0001).</summary>
 public static class ErrorHandling
 {
     public static void Configure(WebApplicationBuilder builder)

src/ProductReviews.Api/Infrastructure/Health.cs

@@ -0,0 +1,45 @@
+using Microsoft.AspNetCore.Diagnostics.HealthChecks;
+using Microsoft.Extensions.Diagnostics.HealthChecks;
+using ProductReviews.Api.Persistence;
+
+namespace ProductReviews.Api.Infrastructure;
+
+/// <summary>/alive = process up + which build, no dependencies — a shared Postgres or
+/// Zitadel outage must never read as a dead process. /health = full readiness, every
+/// dependency included. Both bodies carry the running commit for a deploy gate to grep.</summary>
+public static class Health
+{
+    public const string HealthEndpointPath = "/health";
+    public const string AlivenessEndpointPath = "/alive";
+
+    public static void Configure(WebApplicationBuilder builder)
+    {
+        builder.Services.AddHttpClient(ZitadelHealthCheck.ClientName, client => client.Timeout = TimeSpan.FromSeconds(5));
+
+        builder.Services.AddHealthChecks()
+            .AddCheck<CommitHashHealthCheck>("version", tags: ["live"])
+            .AddDbContextCheck<ReviewsDbContext>("database")
+            .AddCheck<ZitadelHealthCheck>("zitadel");
+    }
+
+    public static void Use(WebApplication app)
+    {
+        app.MapHealthChecks(AlivenessEndpointPath, new HealthCheckOptions
+        {
+            Predicate = registration => registration.Tags.Contains("live"),
+            ResponseWriter = WriteStatusAndCommitAsync,
+        });
+
+        app.MapHealthChecks(HealthEndpointPath, new HealthCheckOptions
+        {
+            ResponseWriter = WriteStatusAndCommitAsync,
+        });
+    }
+
+    // "<status> <commit>" — greppable by a deploy gate, no per-check detail to leak.
+    private static Task WriteStatusAndCommitAsync(HttpContext context, HealthReport report)
+    {
+        context.Response.ContentType = "text/plain";
+        return context.Response.WriteAsync($"{report.Status} {AppVersion.CommitHash}", context.RequestAborted);
+    }
+}

src/ProductReviews.Api/Infrastructure/Observability.cs

@@ -1,11 +1,37 @@
-using ProductReviews.Domain.Persistence;
+using OpenTelemetry;
+using OpenTelemetry.Metrics;
+using OpenTelemetry.Trace;
 
 namespace ProductReviews.Api.Infrastructure;
 
-/// <summary>API-specific health checks. Tracing, metrics, and the /health endpoints
-/// themselves come from ServiceDefaults.</summary>
+/// <summary>OpenTelemetry logging, metrics, and tracing, exported over OTLP when an
+/// endpoint is configured (the Aspire dashboard sets one).</summary>
 public static class Observability
 {
     public static void Configure(WebApplicationBuilder builder)
-        => builder.Services.AddHealthChecks().AddDbContextCheck<ReviewsDbContext>("database");
+    {
+        builder.Logging.AddOpenTelemetry(logging =>
+        {
+            logging.IncludeFormattedMessage = true;
+            logging.IncludeScopes = true;
+        });
+
+        builder.Services.AddOpenTelemetry()
+            .WithMetrics(metrics => metrics
+                .AddAspNetCoreInstrumentation()
+                .AddHttpClientInstrumentation()
+                .AddRuntimeInstrumentation())
+            .WithTracing(tracing => tracing
+                .AddSource(builder.Environment.ApplicationName)
+                .AddAspNetCoreInstrumentation(options =>
+                    options.Filter = context =>
+                        !context.Request.Path.StartsWithSegments(Health.HealthEndpointPath)
+                        && !context.Request.Path.StartsWithSegments(Health.AlivenessEndpointPath))
+                .AddHttpClientInstrumentation());
+
+        if (!string.IsNullOrWhiteSpace(builder.Configuration["OTEL_EXPORTER_OTLP_ENDPOINT"]))
+        {
+            builder.Services.AddOpenTelemetry().UseOtlpExporter();
+        }
+    }
 }