TaskMind

Web APIs (Restful API)

A backend API built with ASP.NET Core, focusing on authentication, transactional consistency, and pragmatic domain-driven design. This project is intentionally backend-only and emphasizes architectural clarity over feature breadth.

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1. Problem Statement & Constraints

This project addresses common real-world backend concerns:

• Stateless authentication using JWT
• Avoiding fat controllers and anemic domain models
• Ensuring domain side effects are consistent with database transactions

Constraints considered:

• No UI layer
• Single database (no microservices, no distributed transactions)
• Focus on correctness and maintainability rather than premature optimization

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2. Architecture Overview

The solution follows Clean Architecture with a DDD‑lite approach:

TaskMind
├─ Domain Layer
│  ├─ TaskMind.Domain.Commons
│  ├─ TaskMind.Domain.Entities
│  ├─ TaskMind.Domain.Events
│  ├─ TaskMind.Domain.ObjectValue
│  └─ TaskMind.Domain.Enums
├─ Application Layer
│  ├─ TaskMind.Application.Commons
|  |  ├─ Interfaces
|  |  └─ Results
│  ├─ TaskMind.Application.Events
│  └─ TaskMind.Application.Services
|     └─ Users
|        ├─ IRequests
|        ├─ IHandlers
|        └─ Dtos
├─ Infrastructure Layer
│  ├─ Persistence (EF Core)
│  └─ Implementations
└─ Presentation Layer
   ├─ TaskMind.Auth.APIS
   |  ├─ Controllers
   |  ├─ Middlewares
   |  └─ Config
   └─ TaskMind.Cases.APIS
      ├─ Controllers
      ├─ Middlewares
      └─ Config

Layering rules:

• Domain has no dependency on any framework
• Application orchestrates use cases
• Infrastructure provides implementations
• Presentation is a thin HTTP layer

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3. Domain Model & Behavior

The domain layer contains:

• Rich entities encapsulating business rules
• Explicit domain events representing meaningful state changes

Example intentions:

• UserLoggedInEvent
• UserChangePasswordEvent

Domain entities do not depend on MediatR or EF Core. Events are simple C# objects.

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4. Domain Events Strategy

Domain events are used to:

• Capture business-relevant occurrences
• Decouple side effects from core domain logic

Design decisions:

• Domain events are raised inside entities
• Events are collected during the transaction
• Event dispatching is orchestrated in the Application layer after persistence succeeds.

This prevents:

• Sending notifications for failed transactions
• Logging or auditing inconsistent state

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5. Application Layer Responsibilities

The application layer:

• Implements use cases via command/query handlers
• Coordinates domain entities and repositories
• Dispatches domain events through MediatR

Rules:

• MediatR exists only in the Application layer
• Handlers may interact with infrastructure via interfaces
• No business logic in controllers

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6. Authentication & Security Design

Authentication is implemented using:

• Short‑lived JWT access tokens

Key behaviors:

1. Login issues access + token

Security considerations:

• Swagger UI is configured to reflect authentication behavior correctly

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7. Persistence & Transaction Management

Persistence is handled with EF Core:

• Explicit Unit of Work abstraction
• Single transaction per request
• Domain events dispatched post‑commit

This ensures:

• Consistent state changes
• No side effects on failed database operations

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8. Error Handling & API Behavior

API behavior is standardized:

• Global exception middleware
• Explicit handling for authentication / authorization failures
• Predictable HTTP response shapes

Controllers are intentionally thin and delegate all logic to the application layer.

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9. Out of Scope (Intentional)

This project intentionally does NOT include:

• Frontend or UI concerns
• CQRS read‑model optimizations
• Distributed caching
• Microservices or message brokers

These are postponed to avoid unnecessary complexity.

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10. Knowledge Demonstrated

This project demonstrates:

• Clean Architecture in a real ASP.NET Core API
• Practical use of domain events
• JWT & refresh token security design
• Transactional consistency with EF Core
• Pragmatic DDD (non‑dogmatic)

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11. Running the Project

dotnet restore
dotnet ef database update
dotnet run

WPF Application