Pulse.Mediator 1.0.7

Pulse.Mediator

Zero-dependency, in-house CQRS mediator for .NET — a drop-in replacement for MediatR.

Install

dotnet add package Pulse.Mediator

Core concepts

Setup

// Program.cs
builder.Services
    .AddPulseMediator(typeof(MyHandler).Assembly)
    .AddPipelineBehavior(typeof(LoggingBehaviour<,>))
    .AddPipelineBehavior(typeof(ValidationBehaviour<,>));

Commands

// Define
public record CreatePatientCommand(string Name, string NhisId) : IRequest<Guid>;

// Handle
public class CreatePatientCommandHandler(IPatientRepository repo)
    : IRequestHandler<CreatePatientCommand, Guid>
{
    public async Task<Guid> Handle(CreatePatientCommand request, CancellationToken ct)
    {
        var patient = Patient.Create(request.Name, request.NhisId);
        await repo.AddAsync(patient, ct);
        return patient.Id;
    }
}

// Dispatch
var id = await mediator.Send(new CreatePatientCommand("Ama Owusu", "GHA-123456"));

Void commands

public record DeletePatientCommand(Guid Id) : IRequest;

public class DeletePatientCommandHandler(IPatientRepository repo)
    : IRequestHandler<DeletePatientCommand>
{
    public async Task Handle(DeletePatientCommand request, CancellationToken ct)
        => await repo.DeleteAsync(request.Id, ct);
}

await mediator.Send(new DeletePatientCommand(patientId));

Notifications (domain events)

public record PatientRegistered(Guid PatientId, string Name) : INotification;

public class SendWelcomeSmsHandler : INotificationHandler<PatientRegistered>
{
    public Task Handle(PatientRegistered n, CancellationToken ct) => ...;
}

await mediator.Publish(new PatientRegistered(id, "Ama Owusu"));

Pipeline behaviors

public sealed class LoggingBehaviour<TRequest, TResponse>(ILogger<TRequest> logger)
    : IPipelineBehavior<TRequest, TResponse>
    where TRequest : notnull
{
    public async Task<TResponse> Handle(TRequest request, RequestHandlerDelegate<TResponse> next, CancellationToken ct)
    {
        logger.LogInformation("Handling {Request}", typeof(TRequest).Name);
        var response = await next(ct);
        logger.LogInformation("Handled {Request}", typeof(TRequest).Name);
        return response;
    }
}

License

MIT — Midas Path Software Solutions