Sendy 1.0.0.5

Sendy

Sendy is a small, lightweight .NET library for implementing the CQRS pattern (Command Query Responsibility Segregation).
It enables clean separation between write and read operations with minimal ceremony, and supports both synchronous and asynchronous handlers.

🚀 Installation

Install via the .NET CLI:

dotnet add package Sendy

Or download it from NuGet.org

⚙️ Configuration

Register Sendy in your Startup.cs or Program.cs:

public void ConfigureServices(IServiceCollection services)
{
    services.AddSendy(typeof(Program).Assembly);
}

🧱 Defining Commands & Queries

Implement one of the following interfaces:

Example: Creating an Order

public class CreateOrderCommand : IRequest<Guid>
{
    public string CustomerId { get; set; }
    public List<string> ProductIds { get; set; }
}

Example: Querying Top Products

public class GetTopSellingProductsQuery : IAsyncRequest<List<ProductDto>>
{
    public int TopCount { get; set; } = 5;
}

🧰 Implementing Handlers

Synchronous Command Handler

public class CreateOrderHandler : IHandler<CreateOrderCommand, Guid>
{
    public Guid Handle(CreateOrderCommand request)
    {
        // Simulate saving to DB
        var orderId = Guid.NewGuid();
        Console.WriteLine($"Order {orderId} created for Customer {request.CustomerId}");
        return orderId;
    }
}

Asynchronous Query Handler

public class GetTopSellingProductsHandler : IAsyncHandler<GetTopSellingProductsQuery, List<ProductDto>>
{
    public async Task<List<ProductDto>> Handle(GetTopSellingProductsQuery request)
    {
        // Simulate async DB call
        await Task.Delay(100);

        return new List<ProductDto>
        {
            new("Product A", 128),
            new("Product B", 115),
            new("Product C", 98)
        }.Take(request.TopCount).ToList();
    }
}

✉️ Dispatching Commands and Queries

Synchronous

var orderId = _sendy.Send(new CreateOrderCommand
{
    CustomerId = "cust-123",
    ProductIds = new List<string> { "prod-1", "prod-2" }
});

Asynchronous

var topProducts = await _sendy.SendAsync(new GetTopSellingProductsQuery
{
    TopCount = 3
});

🧪 DTOs Used in Examples

public record ProductDto(string Name, int UnitsSold);

✅ Why Sendy?

• 🔹 Clean separation of responsibilities (CQRS)
• 🔹 Supports both sync and async flows
• 🔹 Minimal boilerplate
• 🔹 Testable and modular
• 🔹 Fast to set up and extend

📄 License

This project is licensed under the MIT License.