efcore-patterns

EF Core Patterns for ASP.NET Zero

Quick Start

After creating an entity in Core, register it in the EntityFrameworkCore project:

1. Add DbSet to DbContext

// aspnet-core/src/CadentManagement.EntityFrameworkCore/EntityFrameworkCore/CadentManagementDbContext.cs
// Add property inside the class:

public DbSet<Product> Products { get; set; }

2. Configure Entity (if needed)

// In OnModelCreating method of CadentManagementDbContext:

modelBuilder.Entity<Product>(b =>
{
    b.ToTable("Products");
    b.HasIndex(e => e.TenantId);
    b.Property(e => e.Name).HasMaxLength(256).IsRequired();
    b.Property(e => e.Price).HasPrecision(18, 2);
});

3. Create Migration

# From the EntityFrameworkCore project directory
cd aspnet-core/src/CadentManagement.EntityFrameworkCore
dotnet ef migrations add Added_Product_Entity

DbContext Structure

aspnet-core/src/CadentManagement.EntityFrameworkCore/
  EntityFrameworkCore/
    CadentManagementDbContext.cs              # Main DbContext
    CadentManagementEntityFrameworkCoreModule.cs
    Repositories/
      CadentManagementRepositoryBase.cs      # Custom repository base

The DbContext inherits from AbpZeroDbContext<Tenant, Role, User, CadentManagementDbContext>.

Custom Repository (When Needed)

Only create custom repositories when IRepository<T> doesn't suffice (complex queries):

// Interface in Core project
namespace CadentManagement.{Feature};

public interface IProductRepository : IRepository<Product>
{
    Task<List<Product>> GetExpensiveProductsAsync(decimal minPrice);
}

// Implementation in EntityFrameworkCore project
namespace CadentManagement.EntityFrameworkCore.Repositories;

public class ProductRepository : CadentManagementRepositoryBase<Product>, IProductRepository
{
    public ProductRepository(IDbContextProvider<CadentManagementDbContext> dbContextProvider)
        : base(dbContextProvider) { }

    public async Task<List<Product>> GetExpensiveProductsAsync(decimal minPrice)
    {
        return await GetAll()
            .Where(p => p.Price >= minPrice)
            .OrderByDescending(p => p.Price)
            .ToListAsync();
    }
}

Fluent API Common Configurations

Configuration	Code
Table name	b.ToTable("Products")
Required string	b.Property(e => e.Name).HasMaxLength(256).IsRequired()
Decimal precision	b.Property(e => e.Price).HasPrecision(18, 2)
Index	b.HasIndex(e => e.TenantId)
Composite index	b.HasIndex(e => new { e.TenantId, e.Name })
Unique index	b.HasIndex(e => e.Code).IsUnique()
Default value	b.Property(e => e.IsActive).HasDefaultValue(true)
One-to-many	b.HasMany(e => e.Items).WithOne(i => i.Order).HasForeignKey(i => i.OrderId)

Migration Commands

All commands must be run from the EntityFrameworkCore project directory:

cd aspnet-core/src/CadentManagement.EntityFrameworkCore

# 1. Build first (always required before migrations)
dotnet build

# 2. Create migration
dotnet ef migrations add {MigrationName}

# 3. Apply migration to database
dotnet ef database update

# Remove last migration (only if NOT yet applied)
dotnet ef migrations remove

ASP.NET Zero: Applying Migrations

ASP.NET Zero has a dedicated Migrator console project at: aspnet-core/src/CadentManagement.Migrator/

In production or staging, run the Migrator to apply pending migrations:

dotnet run --project aspnet-core/src/CadentManagement.Migrator

In development, dotnet ef database update from the EntityFrameworkCore directory is sufficient.

Constraints

• Never put business logic in repositories
• Custom repos inherit from CadentManagementRepositoryBase<TEntity>
• Never access DbContext from Application layer
• Use Fluent API for configuration, not data annotations on entities

Reference Files

• DbContext: aspnet-core/src/CadentManagement.EntityFrameworkCore/EntityFrameworkCore/CadentManagementDbContext.cs
• Repository base: aspnet-core/src/CadentManagement.EntityFrameworkCore/EntityFrameworkCore/Repositories/CadentManagementRepositoryBase.cs
• Custom repository: aspnet-core/src/CadentManagement.EntityFrameworkCore/EntityFrameworkCore/Authorization/Users/UserRepository.cs

Checklist

• DbSet<TEntity> added to CadentManagementDbContext
• Entity configured in OnModelCreating (if needed)
• Migration created with dotnet ef migrations add (from EntityFrameworkCore directory)
• Migration applied with dotnet ef database update (from EntityFrameworkCore directory)
• Build succeeds after migration
• Custom repository only if IRepository<T> is insufficient