CQRS

This library provides a .NET implementation of the CQRS pattern, allowing you to separate command and query responsibilities in your applications. CQRS promotes a clear separation between the command side that performs operations and the query side that retrieves data.

Installing CQRS

You should install Neoxack.CQRS with NuGet:

Install-Package Neoxack.CQRS

Or via the .NET Core command line interface:

dotnet add package Neoxack.CQRS

Either commands, from Package Manager Console or .NET Core CLI, will download and install Neoxack.CQRS and all required dependencies.

Example

public class PingCommand : ICommand<string>
{
    public string Value { get; }

    public PingCommand(string value)
    {
        Value = value;
    }
}

public class PingCommandHandler : ICommandHandler<PingCommand, string>
{
    public string Handle(PingCommand command)
    {
        return command.Value;
    }
}

public class PingController
{
    private readonly IQueryDispatcher _queryDispatcher;
    private readonly ICommandDispatcher _commandDispatcher;

    public PingController(IQueryDispatcher queryDispatcher, ICommandDispatcher commandDispatcher)
    {
        _queryDispatcher = queryDispatcher;
        _commandDispatcher = commandDispatcher;
    }

    [HttpPost("ping")]
    public string Ping()
    {
        return _commandDispatcher.Execute(new PingCommand("Ping"));
    }
}

Registering with IServiceCollection

CQRS supports Microsoft.Extensions.DependencyInjection.Abstractions directly. To register CQRS services and handlers:

services.AddCQRS(typeof(Startup).Assembly);

This registers:

• ICommandDispather as scoped
• IQueryDispatcher as scoped
• ICommandHandler<,> concrete implementations as scoped
• IQueryHandler<,> concrete implementations as scoped

Benchmarks

BenchmarkDotNet v0.13.10, macOS Sonoma 14.1.2 (23B92) [Darwin 23.1.0]
Apple M2 Pro, 1 CPU, 12 logical and 12 physical cores
.NET SDK 8.0.100
  [Host]     : .NET 6.0.20 (6.0.2023.32017), Arm64 RyuJIT AdvSIMD
  DefaultJob : .NET 6.0.20 (6.0.2023.32017), Arm64 RyuJIT AdvSIMD

Method	Mean	Error	StdDev	Ratio	RatioSD	Gen0	Allocated	Alloc Ratio
Neoxack.CQRS	73.89 ns	0.167 ns	0.140 ns	1.00	0.00	0.0114	24 B	1.00
MediatR	189.76 ns	2.430 ns	2.154 ns	2.57	0.02	0.1760	368 B	15.33

Contributing

Contributions are welcome! Please feel free to submit issues or pull requests.