Trellis.EntityFrameworkCore 3.0.0-alpha.100

EF Core Integration

Thin integration layer that eliminates repetitive EF Core boilerplate when using Trellis value objects and Result<T>.

Installation

dotnet add package Trellis.EntityFrameworkCore

Quick Start

Register all Trellis value objects as scalar properties with a single line in ConfigureConventions:

using Trellis.EntityFrameworkCore;

public class AppDbContext : DbContext
{
    protected override void ConfigureConventions(ModelConfigurationBuilder configurationBuilder)
    {
        // Scans your assembly for CustomerId, OrderStatus, etc.
        // Also auto-scans Trellis.Primitives for EmailAddress, Url, PhoneNumber, etc.
        // Also auto-maps Money properties as owned types (Amount + Currency columns)
        configurationBuilder.ApplyTrellisConventions(typeof(CustomerId).Assembly);
    }

    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {
        // No HasConversion() boilerplate needed — just configure keys, indexes, constraints
        modelBuilder.Entity<Customer>(b =>
        {
            b.HasKey(c => c.Id);
            b.Property(c => c.Name).HasMaxLength(100).IsRequired();
            b.Property(c => c.Email).HasMaxLength(254).IsRequired();
        });
    }
}

Money Properties — Zero Configuration

Money properties are automatically mapped as owned types with proper column naming and precision:

No OwnsOne calls needed — just declare Money properties on your entities and they work.

Result-Returning SaveChanges

// Returns Result<int> instead of throwing on conflicts or FK violations
var result = await context.SaveChangesResultAsync(ct);

// Returns Result<Unit> when you don't need the count
var result = await context.SaveChangesResultUnitAsync(ct);

Query Extensions

// Maybe-returning queries (no exception on missing)
Maybe<Customer> customer = await context.Customers
    .FirstOrDefaultMaybeAsync(c => c.Id == customerId, ct);

// Result-returning queries
Result<Customer> customer = await context.Customers
    .FirstOrDefaultResultAsync(
        c => c.Id == customerId,
        Error.NotFound("Customer", customerId),
        ct);

// Specification pattern
var activeSpec = new ActiveCustomerSpec();
var activeCustomers = await context.Customers
    .Where(activeSpec)
    .ToListAsync(ct);

Related Packages

• Trellis.Results — Core Result<T> and Maybe<T> types
• Trellis.Primitives — Value object base classes and built-in types
• Trellis.DomainDrivenDesign — Specification<T>, Entity<T>, Aggregate<T>

License

MIT — see LICENSE for details.