Simple.CommandsAndQueries

This is a basic library of interfaces to use for CQRS commands and queries.

It is inspired by the work of Vladimir Khorikov and his course repository

It provides the basic interfaces

• ICommand
• IQuery

Along with handler interfaces

• ICommandHandler
• ICommandAsyncHandler
• IQueryHandler
• IQueryAsyncHandler

It also includes a dispatcher with interface to be used for processing commands and queries as well as extensions to the IServiceCollection to register the dispatcher and all commands and queries.

Registration sample

builder.Services
   .AddCommandAndQueryDispatcher()
   .AddCommandAndQueryHandlers(typeof(MyQueryAsyncHandler).Assembly);

Sample usage

public class MyClass
{
    private readonly ICQRSDispatcher _cqrs;

    public MyClass(ICQRSDispatcher cqrs) => _cqrs = cqrs;

    public string GetVersion() => _cqrs.Dispatch(new GetVersionQuery());

    public async Task<MyModel> GetModelAsync() => await _cqrs.DispatchAsync(new GetModelQuery());
}

public class GetVersionQuery : IQuery<string> { }

public class GetVersionQueryHandler : IQueryHandler<GetVersionQuery, string>
{
    public string Handle(GetVersionQuery query) => "1.0";
}

public class GetModelQuery : IQuery<MyModel> { }

public class GetModelQueryHandler : IQueryAsyncHandler<GetModelQuery, MyModel>
{
    public async Task<MyModel> HandleAsync(GetModelQuery query) => await ReadMyModelFromDbAsync());
}