AccountSubSystem.Handlers 1.0.0

AccountSubSystem.Handlers

CQRS command and query handlers for the BDJobs Account SubSystem.

This package is the top-level orchestration layer of the Account SubSystem. It contains all the Handler classes that process commands (write operations) and queries (read operations), wiring together the Repositories, Aggregate Roots, and the Service Bus — following the CQRS pattern used across all BDJobs subsystems.

📦 Installation

.NET CLI

dotnet add package AccountSubSystem.Handlers --version 1.0.0

Package Manager Console

NuGet\Install-Package AccountSubSystem.Handlers -Version 1.0.0

PackageReference (add to your .csproj)

<PackageReference Include="AccountSubSystem.Handlers" Version="1.0.0" />

📋 Requirements

📁 What's Inside

This package contains:

• Query Handlers — process read requests (e.g. GetUserQueryHandler, GetBillTrackingQueryHandler)
• Command Handlers — process write requests (e.g. CreateUserCommandHandler)
• DI registration — AddAccountHandlers() extension to register all handlers in one call
• Validation — FluentValidation validators wired per handler via the Service Bus pipeline

🚀 Usage

Step 1 — Register handlers in Program.cs

builder.Services.AddAccountHandlers(builder.Configuration);

Step 2 — Dispatch a query from your Controller

using AccountSubSystem.DTOs;

[ApiController]
[Route("api/[controller]")]
public class AccountController : ControllerBase
{
    private readonly IServiceBus _serviceBus;

    public AccountController(IServiceBus serviceBus)
    {
        _serviceBus = serviceBus;
    }

    [HttpGet("{userId}")]
    public async Task<IActionResult> GetUser(int userId)
    {
        var query = new GetUserQuery { UserId = userId };
        var result = await _serviceBus.SendAsync(query);
        return Ok(result);
    }
}

Step 3 — How a Handler looks internally

public class GetUserQueryHandler : IQueryHandler<GetUserQuery, UserResponseDto>
{
    private readonly IUserRepository _repository;

    public GetUserQueryHandler(IUserRepository repository)
    {
        _repository = repository;
    }

    public async Task<UserResponseDto> Handle(GetUserQuery query)
    {
        // 1. Fetch raw data from DB
        var entities = await _repository.GetByIdAsync(query.UserId);

        // 2. Build Aggregate Root
        var aggregateRoot = UserAggregateRoot.FromEntities(entities);

        // 3. Apply business rules
        aggregateRoot.ApplyBusinessRules();

        // 4. Return DTO
        return aggregateRoot.ToResponseDto();
    }
}

🔗 Dependencies

This package is the top of the AccountSubSystem tree and pulls in all other AccountSubSystem packages automatically:

All dependencies are installed automatically. You only need to install AccountSubSystem.Handlers and everything else comes with it.

🏗️ Architecture

AccountSubSystem.Handlers is at the top of the AccountSubSystem dependency tree. Installing this single package gives you the entire AccountSubSystem stack.

AccountSubSystem.Handlers  ← YOU ARE HERE (installs everything below)
    ├── AccountSubSystem.Aggregators
    │       └── AccountSubSystem.DTOs
    ├── AccountSubSystem.Repositories
    │       └── AccountSubSystem.Aggregators
    ├── ServiceBus.Handler
    │       └── SharedSubSystem.Handler
    ├── SharedSubSystem.DTOs
    ├── SharedSubSystem.Handler
    └── SharedSubSystem.Services

Full data flow:

HTTP Request
    → API Controller
        → IServiceBus.SendAsync(query)
            → Handler.Handle(query)           ← HERE
                → Repository.GetAsync()
                → AggregateRoot.FromEntities()
                → ApplyBusinessRules()
                → ToResponseDto()
    → HTTP Response

⚠️ Notes

• If you only need DTOs (e.g. in a client project), install AccountSubSystem.DTOs instead — it is much lighter.
• If you need the domain logic without database access, install AccountSubSystem.Aggregators.
• Install AccountSubSystem.Handlers only in your API or subsystem project that actually processes requests.

👤 Author

BDJobs — Internal NuGet package for the BDJobs Conveyance Billing System.