abp-entity-patterns

ABP Entity Patterns

Domain layer patterns for ABP Framework following DDD principles.

Architecture Layers

Domain.Shared    → Constants, enums, shared types
Domain           → Entities, repositories, domain services, domain events
Application.Contracts → DTOs, application service interfaces
Application      → Application services, mapper profiles
EntityFrameworkCore → DbContext, repository implementations
HttpApi          → Controllers
HttpApi.Host     → Startup, configuration

Key principle: Dependencies flow downward. Application depends on Domain, but Domain never depends on Application.

Entity Base Classes

Choosing the Right Base Class

Base Class	Use When
Entity<TKey>	Simple entity, no auditing
AuditedEntity<TKey>	Need creation/modification tracking
FullAuditedEntity<TKey>	Need soft delete + full audit
AggregateRoot<TKey>	Root entity of an aggregate
FullAuditedAggregateRoot<TKey>	Most common - full features

Standard Entity Pattern

public class Patient : FullAuditedAggregateRoot<Guid>
{
    public string FirstName { get; private set; }
    public string LastName { get; private set; }
    public string Email { get; private set; }
    public DateTime DateOfBirth { get; private set; }
    public bool IsActive { get; private set; }

    // Required for EF Core
    protected Patient() { }

    // Constructor with validation
    public Patient(
        Guid id,
        string firstName,
        string lastName,
        string email,
        DateTime dateOfBirth)
        : base(id)
    {
        SetName(firstName, lastName);
        SetEmail(email);
        DateOfBirth = dateOfBirth;
        IsActive = true;
    }

    // Domain methods with validation
    public void SetName(string firstName, string lastName)
    {
        FirstName = Check.NotNullOrWhiteSpace(firstName, nameof(firstName), maxLength: 100);
        LastName = Check.NotNullOrWhiteSpace(lastName, nameof(lastName), maxLength: 100);
    }

    public void SetEmail(string email)
    {
        Email = Check.NotNullOrWhiteSpace(email, nameof(email), maxLength: 256);
    }

    public void Activate() => IsActive = true;
    public void Deactivate() => IsActive = false;
}