feat: Reviews aggregate + FluentValidation + Trellis.Testing + ServiceDefaults

[xavierjohn]

PR 5 — Reviews + FluentValidation + Trellis.Testing + Trellis.ServiceDefaults

Capstone of the 5-PR showcase arc. Adds the final aggregate (MenuReview), bundles
three previously-unwired Trellis features (AddTrellisFluentValidation,
Trellis.Testing matchers, Trellis.ServiceDefaults composition builder), and
collapses ~30 lines of services.Add*(...) calls in the composition root into one
fluent AddTrellis(t => t.Use*(...)) expression.

TL;DR

What	Where	Cookbook
MenuReview aggregate (Submit, UpdateContent)	Domain/src/MenuReview/Entities/MenuReview.cs	Recipe 1
2 domain events (MenuReviewSubmitted, MenuReviewUpdated)	Domain/src/MenuReview/Events/	Recipe 17
POST /menu-reviews · PUT /menu-reviews/{id} · GET /menu-reviews/{id} · GET /menu-reviews/for-menu/{menuId}	MenuReviewsController	Recipes 3 + 22
FluentValidation at the command boundary via AbstractValidator<TCommand> + auto-wired Mediator behavior	SubmitMenuReviewCommandValidator, UpdateMenuReviewCommandValidator	Mediator validation
Trellis.Testing matchers (.Should().BeSuccess() / .BeFailureOfType<>() / .Unwrap())	Domain/tests/MenuReviewTests.cs	trellis-api-testing.md
Trellis.ServiceDefaults composition builder — AddTrellis(t => t.Use*(...)) replaces 10+ individual Add* calls	Api/src/DependencyInjection.cs	trellis-api-servicedefaults.md
Stub cleanup: orphan MenuReviewId in the wrong namespace	Menu.cs, MenuDto.cs, MenuRepositoryTests.cs	—

FluentValidation kicking in at the wire

POST /menu-reviews
{ "menuId":"...", "dinnerId":"...", "rating":99, "comment":"" }

HTTP/1.1 422 Unprocessable Entity
Content-Type: application/problem+json
{
  "status": 422, "code": "invalid-input",
  "errors": {
    "Rating":  ["Rating must be between 1 and 5."],
    "Comment": ["Comment is required."]
  }
}

Both SubmitMenuReviewCommand and UpdateMenuReviewCommand have a matching
AbstractValidator<TCommand> in Application/MenuReviews/Validators/. Once
UseFluentValidation(typeof(SubmitMenuReviewCommandValidator).Assembly) is wired,
the framework scans the assembly, registers every IValidator<T> as scoped, and
plugs them into the existing ValidationBehavior<,> mediator slot. Failures
aggregate into a single Error.InvalidInput which the ASP boundary serialises as
RFC 4918 Problem Details. Per-handler AddScoped<IValidator<X>, XValidator>() is
also supported (AOT-safe variant).

The composition root before vs after

Before (PR 4 tip, ~70 lines of services.Add*(...) in Api/DependencyInjection.cs):

services.AddTrellisAspWithScalarValidation();
services.AddClaimsActorProvider(opts => opts.ActorIdClaim = "sub");
services.AddResourceAuthorization(typeof(UpdateMenuCommand).Assembly, typeof(HostResourceLoader).Assembly);
services.AddDomainEventDispatch();
services.AddDomainEventHandler<DinnerScheduled, LogDinnerScheduledHandler>();
// ... 5 more event handler registrations
services.AddTrellisIdempotency(opts => { ... });
services.AddInMemoryIdempotencyStore();
services.AddSingleton(TimeProvider.System);

After (PR 5, one fluent AddTrellis(...) expression):

services.AddTrellis(t => t
    .UseAsp()
    .UseScalarValueValidation()
    .UseProblemDetails()
    .UseMediator()
    .UseClaimsActorProvider(opts => opts.ActorIdClaim = "sub")
    .UseResourceAuthorization(typeof(UpdateMenuCommand).Assembly, typeof(HostResourceLoader).Assembly)
    .UseFluentValidation(typeof(SubmitMenuReviewCommandValidator).Assembly)
    .UseDomainEvents()
    .UseIdempotency(opts => { opts.Ttl = TimeSpan.FromHours(24); opts.MaxRequestBodyBytes = 256 * 1024; }));
services.AddInMemoryIdempotencyStore();

The builder fixes the mutually-required call order so misconfigurations fail at
startup, not at request time. Per-type registrations (AddTrellisRouteConstraint<HostId>,
AddDomainEventHandler<DinnerScheduled, LogDinnerScheduledHandler>,
AddInMemoryIdempotencyStore, AddSingleton(TimeProvider.System)) stay separate —
those are "application-owned" per the docs and not covered by the builder.

Test-side cleanup with Trellis.Testing matchers

// Before (PR 2-4 style — still works, kept for the existing tests):
result.IsSuccess.Should().BeTrue();
var error = result.Match(_ => null!, e => e).Should().BeOfType<Error.InvalidInput>().Subject;
error.Rules.Items.Should().ContainSingle().Which.ReasonCode.Should().Be("...");

// After (PR 5 MenuReviewTests):
result.Should().BeSuccess();
result.Should().BeFailureOfType<Error.InvalidInput>();
var review = result.Unwrap();  // test-only; doesn't leak into production code

Older Dinner/Reservation tests kept in their existing style to avoid churn — the 8
new MenuReviewTests use the new matchers exclusively so future authors have a
side-by-side reference.

Domain-aggregate cleanup (drive-by)

A pre-existing stub Domain/src/MenuReview/ValueObjects/MenuId.cs defined
MenuReviewId in the wrong namespace (BuberDinner.Domain.Menu.ValueObject
instead of BuberDinner.Domain.MenuReview.ValueObject). Menu.cs consumed it
through that wrong namespace, papering over the bug. PR 5 deletes the stub, adds
the canonical MenuReviewId.cs under the right namespace, and updates the 3
consumers.

Build, test

• 0 warnings / 0 errors
• Domain 45/45 (+8 new MenuReviewTests using Trellis.Testing matchers)
• Application 1/1 (unchanged)
• Api 69/69 (+7 new MenuReviewTests covering all wire scenarios)
• Infrastructure 0/2 (live-Cosmos baseline, pre-existing)

Wire scenarios covered by MenuReviewTests:

1. Submit happy path → 201 + ETag + Location
2. Submit rating=99 → 422 with errors.Rating (FluentValidation)
3. Submit comment="" → 422 with errors.Comment (FluentValidation)
4. Submit against missing menu → 404 (Recipe 22 fail-loud)
5. Update with rating=0 → 422 with errors.Rating (validator runs on Update too)
6. Cross-guest update → 404 (NotFound-leak-shield)
7. Paginated list — 7 items at limit=3 → 3+3+1, last page next=null

Commit walkthrough (7 commits)

#	sha	Scope
1	360a8a2	chore(deps): 3 new packages + FluentAssertions 6.12 → 7.2.2 (Trellis.Testing requirement)
2	073c298	feat(domain): MenuReview aggregate + 2 events + 8 tests + orphan stub cleanup
3	1dc771e	feat(infra+app): repo + 4 commands/queries + 2 FluentValidation rules + 2 log handlers
4	995e45a	feat(api): MenuReviewsController + DTOs
5	26828bf	refactor(api): collapse Add* composition into AddTrellis(t => t.Use*(...)) builder
6	6f2a336	test(api): 7 integration tests
7	f157b4e	docs: walkthrough + 4 .http demos + Aggregates.MenuReview.md

Roadmap complete

This is the final PR in the showcase arc. After merge, BuberDinner exercises every
Trellis V3 package shipped today except Trellis.EntityFrameworkCore:

• Trellis.Core · Trellis.Primitives (PR Migrate to Trellis 3.0.0-alpha.342 on .NET 10 (closed Error union, AddTrellisBehaviors, 3-of-3 framework regressions adopted) #26)
• Trellis.Asp · Trellis.Http.Abstractions · Trellis.Authorization (PR feat: ETag conditional requests + resource-based authorization + scalar VO route constraints #27)
• Trellis.Mediator · Trellis.StateMachine (PR feat: Dinner aggregate with Stateless state machine + per-transition domain events #28)
• Trellis.Mediator.FluentValidation · Trellis.Testing · Trellis.ServiceDefaults (PR feat: Reservations aggregate + IETF Idempotency-Key middleware + multi-aggregate fail-loud #30 + this)

In-memory persistence is intentional for the showcase. An EF Core swap is the obvious
clean follow-up — IRepository<T> is the only contact point the application layer
sees, so swapping the implementation requires no Application/Api changes.

[Copilot]

Pull request overview

This PR completes the showcase arc by adding the MenuReview aggregate and wiring additional Trellis V3 capabilities (Mediator FluentValidation integration, Trellis.Testing matchers, and the Trellis.ServiceDefaults composition builder). It extends the API surface with menu-review endpoints, adds in-memory persistence + pagination support for reviews, and updates docs and request samples to demonstrate the new behavior end-to-end.

Changes:

• Add MenuReview domain aggregate + domain events, plus supporting in-memory repository and persistence DTO adjustments.
• Introduce menu-review application commands/queries/handlers and FluentValidation validators wired into the Mediator pipeline.
• Add menu-review API endpoints + integration tests, and refactor the API composition root to use services.AddTrellis(t => t.Use*(...)) (ServiceDefaults).

Reviewed changes

Copilot reviewed 36 out of 36 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
Requests/MenuReviews/UpdateReview.http	Adds an update-review HTTP demo with expected responses.
Requests/MenuReviews/SubmitReview.http	Adds a submit-review HTTP demo request/response shape.
Requests/MenuReviews/SubmitReview-ValidationFailure.http	Adds validation-failure demo scenarios for submit review.
Requests/MenuReviews/ListReviewsForMenu.http	Adds paginated list-for-menu HTTP demo.
Infrastructure/tests/MenuRepositoryTests.cs	Updates test imports to reference moved MenuReviewId namespace.
Infrastructure/src/Persistence/Memory/MenuReviewInMemoryRepository.cs	Adds in-memory repository for MenuReview with ETag tracking and paging.
Infrastructure/src/Persistence/Dto/MenuDto.cs	Updates DTO mapping to use canonical MenuReviewId namespace.
Infrastructure/src/DependencyInjection.cs	Registers MenuReviewInMemoryRepository for both in-memory and Cosmos fallback wiring.
Domain/tests/MenuReviewTests.cs	Adds domain tests using Trellis.Testing matchers for MenuReview.
Domain/tests/BuberDinner.Domain.Tests.csproj	Adds Trellis.Testing package reference for domain tests.
Domain/src/MenuReview/ValueObjects/MenuReviewId.cs	Fixes MenuReviewId into the correct MenuReview namespace.
Domain/src/MenuReview/Events/MenuReviewEvents.cs	Adds MenuReviewSubmitted and MenuReviewUpdated domain events.
Domain/src/MenuReview/Entities/MenuReview.cs	Implements MenuReview aggregate with validation + update behavior.
Domain/src/Menu/Menu.cs	Updates imports for moved MenuReviewId namespace.
Docs/PR5_REVIEWS_FLUENTVALIDATION_TESTING_DEFAULTS.md	Adds PR5 walkthrough documentation (reviews + validation + testing + defaults).
Docs/DomainModels/Aggregates.MenuReview.md	Replaces stub with real aggregate documentation and wire shape.
Directory.Packages.props	Adds/bumps central package versions (ServiceDefaults, Testing, FV adapter, FluentAssertions).
Application/src/MenuReviews/Validators/MenuReviewValidators.cs	Adds FluentValidation validators for submit/update commands.
Application/src/MenuReviews/Queries/ListReviewsForMenuQuery.cs	Adds paginated list query/handler for reviews by menu.
Application/src/MenuReviews/Queries/GetMenuReviewQuery.cs	Adds get-by-id query/handler for reviews.
Application/src/MenuReviews/Events/MenuReviewEventHandlers.cs	Adds log-only domain event handlers for review submit/update.
Application/src/MenuReviews/Commands/UpdateMenuReviewCommand.cs	Adds update command/handler with ownership check + persistence update.
Application/src/MenuReviews/Commands/SubmitMenuReviewCommandHandler.cs	Adds submit handler (fail-loud on missing menu) + persistence add.
Application/src/MenuReviews/Commands/SubmitMenuReviewCommand.cs	Adds submit command type.
Application/src/BuberDinner.Application.csproj	Adds Trellis.Mediator.FluentValidation package reference.
Application/src/Abstractions/Persistence/IMenuReviewRepository.cs	Introduces IMenuReviewRepository contract with paging method.
Api/tests/BuberDinner.Api.Tests.csproj	Adds Trellis.Testing package reference for API tests.
Api/tests/2022-12-21/MenuReviewTests.cs	Adds end-to-end integration tests for submit/update/get/list review scenarios.
Api/src/Program.cs	Removes explanatory comment around middleware ordering (keeps behavior).
Api/src/DependencyInjection.cs	Refactors composition root to AddTrellis(...Use*...) + wires review route constraint + event handlers.
Api/src/BuberDinner.Api.csproj	Adds Trellis.ServiceDefaults package reference.
Api/src/2022-12-21/Models/MenuReviews/MenuReviewDtos.cs	Adds menu-review request/response DTOs + Mapster mapping config.
Api/src/2022-12-21/Controllers/MenuReviewsController.cs	Adds menu-review endpoints (submit/get/update/list) with ETag + pagination.
.github/trellis-api-testing.md	Adds Trellis.Testing API reference drop for repo-local guidance.
.github/trellis-api-servicedefaults.md	Adds Trellis.ServiceDefaults API reference drop for repo-local guidance.
.github/trellis-api-mediator-fluentvalidation.md	Adds Trellis.Mediator.FluentValidation API reference drop for repo-local guidance.

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