BookStore Cheat Sheet

IDs & Timestamps

csharp
1var id = Guid.CreateVersion7();           // ✅ UUIDv7
2var now = DateTimeOffset.UtcNow;          // ✅ UTC timestamp

Event (past tense, record)

csharp
1public record BookAdded(Guid Id, string Title, decimal Price);

Command (record)

csharp
1public record AddBookCommand(string Title, decimal Price);

Aggregate Apply Method

csharp
1public void Apply(BookAdded @event)
2{
3    Id = @event.Id;
4    Title = @event.Title;
5}

Handler (static, Wolverine)

csharp
1public static class AddBookHandler
2{
3    public static BookAdded Handle(AddBookCommand cmd) =>
4        new(Guid.CreateVersion7(), cmd.Title, cmd.Price);
5}

HybridCache Query

csharp
1var result = await cache.GetOrCreateAsync(
2    $"books:{culture}",
3    async ct => await session.Query<BookProjection>().ToListAsync(ct),
4    tags: [CacheTags.BookList],
5    cancellationToken: ct);

Cache Invalidation

csharp
1await cache.RemoveByTagAsync(CacheTags.BookList, ct);

SSE Notification

csharp
1public record BookUpdatedNotification(Guid Id) : IDomainEventNotification;

TUnit Test

csharp
1[Test]
2public async Task Should_Create_Book()
3{
4    var result = await client.CreateBookAsync(request);
5    await Assert.That(result.Id).IsNotNull();
6}

Namespace

csharp
1namespace BookStore.ApiService.Handlers;  // ✅ File-scoped

Related Skills

• /wolverine__guide - All Wolverine write operations (create, update, delete)
• /marten__guide - Aggregates, projections, and query endpoints