DKNet.SlimBus.Extensions 10.1.19

DKNet.SlimBus.Extensions

CQRS and messaging glue on top of SlimMessageBus, wired for EF Core — a lighter, result-based alternative to MediatR. Command/query handlers get fluent contracts, successful writes are auto-saved to your DbContext, and EF Core domain events are forwarded onto the bus.

Install

dotnet add package DKNet.SlimBus.Extensions

Features

• Command contracts — Fluents.Requests.INoResponse / IWitResponse<TResponse>, with matching IHandler<> interfaces; auto-saves the DbContext after a successful handler, skips it on failure or null.
• Query contracts — Fluents.Queries.IWitResponse<TResponse> and IWitPageResponse<TResponse> (paged, via X.PagedList.EF); queries never trigger auto-save.
• Event consumers — Fluents.EventsConsumers.IHandler<TEvent> for reacting to messages/domain events.
• Domain event publishing — SlimBusEventPublisher forwards events raised by DKNet.EfCore.Events onto the bus, copying event AdditionalData into message headers.
• Pluggable interceptors — auto-save is a standard SlimMessageBus IRequestHandlerInterceptor<,>; add your own for validation, logging, etc.
• Transport-agnostic — brings no provider; plug in SlimMessageBus.Host.Memory, Azure Service Bus, or any other SlimMessageBus provider yourself.

Quick start

using DKNet.SlimBus.Extensions;
using FluentResults;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.DependencyInjection;
using SlimMessageBus.Host;
using SlimMessageBus.Host.Memory;
using SlimMessageBus.Host.Serialization.SystemTextJson;

services.AddDbContext<AppDbContext>(o => o.UseSqlServer(connectionString));
services.AddSlimBusEfCoreInterceptor<AppDbContext>();

services.AddSlimMessageBus(mbb => mbb
    .AddJsonSerializer()
    .AddServicesFromAssembly(typeof(Program).Assembly)
    .AddChildBus("Memory", bus => bus
        .WithProviderMemory()
        .AutoDeclareFrom(typeof(Program).Assembly)));

// Command
public record CreateProduct(string Name, decimal Price) : Fluents.Requests.IWitResponse<Guid>;

internal sealed class CreateProductHandler(AppDbContext db)
    : Fluents.Requests.IHandler<CreateProduct, Guid>
{
    public async Task<IResult<Guid>> OnHandle(CreateProduct request, CancellationToken cancellationToken)
    {
        var product = new Product(request.Name, request.Price);
        await db.Products.AddAsync(product, cancellationToken);
        return Result.Ok(product.Id); // DbContext is saved automatically after this returns
    }
}

Configuration — registration surface

There is no options type and no IConfiguration section. What you vary is which of the two registrations you call and with which DbContext; everything else (AddSlimMessageBus, serializers, providers, handler discovery) is SlimMessageBus's own API.

Auto-save behaviour is fixed, not switchable:

Public extension points

The auto-save interceptor, its DbContext registry, and the LazyMap/LazyResult implementations are all internal: you opt in through the two registration methods, not by implementing those types.

Documentation

Full feature reference, diagrams, and composition with DKNet.EfCore.Events / DKNet.EfCore.Specifications: https://github.com/baoduy/DKNet/blob/main/docs/Messaging/DKNet.SlimBus.Extensions.md