Imported from acontplus/acontplus-dotnet-libs (.agents/skills/dotnet-data-driven-api/SKILL.md). Install upstream with npx skills add acontplus/acontplus-dotnet-libs --skill dotnet-data-driven-api. Copyright stays with the author.

Create a Data-Driven API with Acontplus

When to Use

Activate this skill when:

• You need to add a new entity and its repository/API endpoints to apps/src/Demo.*.
• You need to set up EF Core entity configurations using Acontplus persistence patterns.
• You are implementing repository contracts using Acontplus.Persistence.Common.

Entity & Repository Design Pattern

1. Define the Entity (in apps/src/Demo.Domain)

namespace Demo.Domain.Entities;

public class Product : BaseEntity<int>
{
    public required string Name { get; set; }
    public string? Sku { get; set; }
    public decimal Price { get; set; }
    public bool IsActive { get; set; } = true;
}

2. Repositories in Acontplus

Acontplus provides generic repository abstractions in Acontplus.Core.Abstractions.Persistence / Acontplus.Persistence.Common:

• IRepository<T> with GetByIdAsync, GetQueryable(), AddAsync, UpdateAsync, DeleteAsync.
• IUnitOfWork with GetRepository<T>(), SaveChangesAsync(), BeginTransactionAsync().

For specialized domain queries, extend or implement custom methods:

public interface IProductRepository : IRepository<Product>
{
    Task<IReadOnlyList<Product>> GetActiveProductsAsync(CancellationToken cancellationToken = default);
}

3. Configure the Entity (in apps/src/Demo.Infrastructure)

namespace Demo.Infrastructure.Configurations;

public class ProductConfiguration : IEntityTypeConfiguration<Product>
{
    public void Configure(EntityTypeBuilder<Product> builder)
    {
        builder.HasKey(e => e.Id);
        builder.Property(e => e.Name).HasMaxLength(200).IsRequired();
        builder.Property(e => e.Sku).HasMaxLength(50);
        builder.Property(e => e.Price).HasPrecision(18, 2);
    }
}

4. Create and Apply Migrations

dotnet ef migrations add AddProduct --project apps/src/Demo.Infrastructure --startup-project apps/src/Demo.Api
dotnet ef database update --project apps/src/Demo.Infrastructure --startup-project apps/src/Demo.Api

5. Create the Application Service (in apps/src/Demo.Application)

Use the Result<T, DomainError> pattern from Acontplus.Core for all business operations.

6. Create API Endpoints (in apps/src/Demo.Api)

Use ASP.NET Core Minimal APIs with endpoint modules and Result<T, DomainError>.

Best Practices

• Use Fluent API in IEntityTypeConfiguration<T> — never Data Annotations.
• Never expose entities directly in API responses; always use DTOs.
• Use AsNoTracking() for read-only queries.
• Always order migrations chronologically and commit them with the model change.
• Use Result<T, DomainError> — never throw exceptions for business validation.