Initial EfCoreKit.Core infrastructure: soft delete, audit, DI

Introduce modular core with soft delete, audit, multi-tenancy, and bulk ops support. Add EfCoreKitDbContext<TContext>, fluent options, DI registration, and extension methods for DbSet/IQueryable. Stub out interceptors, filters, and provider-specific bulk executors. Add internal helpers and global usings. Most logic is scaffolded with TODOs for future implementation.

Author: Clifftech123

Directory.Packages.props

@@ -11,7 +11,7 @@
     <PackageVersion Include="Microsoft.EntityFrameworkCore.Sqlite" Version="10.0.0" />
     <PackageVersion Include="Microsoft.EntityFrameworkCore.InMemory" Version="10.0.0" />
     <PackageVersion Include="Npgsql.EntityFrameworkCore.PostgreSQL" Version="10.0.0" />
-    <PackageVersion Include="Pomelo.EntityFrameworkCore.MySql" Version="9.0.0" />
+    <PackageVersion Include="MySql.EntityFrameworkCore" Version="10.0.1" />
   </ItemGroup>
 
   <!-- DI -->

src/EfCoreKit.Core/Context/EfCoreKitDbContext.cs

@@ -1 +1,89 @@
+using EfCoreKit.Abstractions.Interfaces;
+using Microsoft.EntityFrameworkCore;
 
+namespace EfCoreKit.Core.Context;
+
+/// <summary>
+/// Base <see cref="DbContext"/> that provides automatic soft delete, audit trail,
+/// multi-tenancy, and bulk operation support.
+/// </summary>
+/// <typeparam name="TContext">The derived context type.</typeparam>
+public abstract class EfCoreKitDbContext<TContext> : DbContext
+    where TContext : DbContext
+{
+    private readonly EfCoreKitOptions _options;
+    private readonly IUserProvider? _userProvider;
+    private readonly ITenantProvider? _tenantProvider;
+
+    /// <summary>
+    /// Initializes a new instance of the <see cref="EfCoreKitDbContext{TContext}"/> class.
+    /// </summary>
+    /// <param name="options">The EF Core context options.</param>
+    /// <param name="kitOptions">The EfCoreKit configuration options.</param>
+    protected EfCoreKitDbContext(
+        DbContextOptions<TContext> options,
+        EfCoreKitOptions kitOptions)
+        : base(options)
+    {
+        _options = kitOptions ?? throw new ArgumentNullException(nameof(kitOptions));
+    }
+
+    /// <summary>
+    /// Initializes a new instance of the <see cref="EfCoreKitDbContext{TContext}"/> class
+    /// with user and tenant provider support.
+    /// </summary>
+    /// <param name="options">The EF Core context options.</param>
+    /// <param name="kitOptions">The EfCoreKit configuration options.</param>
+    /// <param name="userProvider">The user provider for audit trail.</param>
+    /// <param name="tenantProvider">The tenant provider for multi-tenancy.</param>
+    protected EfCoreKitDbContext(
+        DbContextOptions<TContext> options,
+        EfCoreKitOptions kitOptions,
+        IUserProvider? userProvider,
+        ITenantProvider? tenantProvider)
+        : base(options)
+    {
+        _options = kitOptions ?? throw new ArgumentNullException(nameof(kitOptions));
+        _userProvider = userProvider;
+        _tenantProvider = tenantProvider;
+    }
+
+    /// <summary>
+    /// Gets the current EfCoreKit configuration options.
+    /// </summary>
+    protected EfCoreKitOptions Options => _options;
+
+    /// <inheritdoc />
+    public override async Task<int> SaveChangesAsync(CancellationToken cancellationToken = default)
+    {
+        OnBeforeSaveChanges();
+        return await base.SaveChangesAsync(cancellationToken);
+    }
+
+    /// <inheritdoc />
+    protected override void OnModelCreating(ModelBuilder modelBuilder)
+    {
+        base.OnModelCreating(modelBuilder);
+        ConfigureGlobalFilters(modelBuilder);
+    }
+
+    /// <summary>
+    /// Hook called before changes are saved. Handles audit trail, soft delete, and tenant assignment.
+    /// </summary>
+    private void OnBeforeSaveChanges()
+    {
+        // TODO: Implement audit trail (HandleAuditableEntities)
+        // TODO: Implement soft delete interception (HandleSoftDeletableEntities)
+        // TODO: Implement tenant assignment (HandleTenantEntities)
+    }
+
+    /// <summary>
+    /// Applies global query filters for soft delete and multi-tenancy.
+    /// </summary>
+    /// <param name="modelBuilder">The model builder.</param>
+    private void ConfigureGlobalFilters(ModelBuilder modelBuilder)
+    {
+        // TODO: Apply ISoftDeletable global filter
+        // TODO: Apply ITenantEntity global filter
+    }
+}

src/EfCoreKit.Core/Context/EfCoreKitDbContextOptions.cs

@@ -1 +1,117 @@
+using EfCoreKit.Abstractions.Interfaces;
 
+namespace EfCoreKit.Core.Context;
+
+/// <summary>
+/// Configuration options for EfCoreKit features.
+/// Use the fluent methods to enable features before passing to <see cref="ServiceCollectionExtensions"/>.
+/// </summary>
+public sealed class EfCoreKitOptions
+{
+    /// <summary>
+    /// Gets a value indicating whether soft delete is enabled for entities implementing <see cref="ISoftDeletable"/>.
+    /// </summary>
+    public bool SoftDeleteEnabled { get; private set; }
+
+    /// <summary>
+    /// Gets a value indicating whether cascade soft delete is enabled.
+    /// </summary>
+    public bool CascadeSoftDeleteEnabled { get; private set; }
+
+    /// <summary>
+    /// Gets a value indicating whether audit trail is enabled for entities implementing <see cref="IAuditable"/>.
+    /// </summary>
+    public bool AuditTrailEnabled { get; private set; }
+
+    /// <summary>
+    /// Gets a value indicating whether full audit logging to a dedicated table is enabled.
+    /// </summary>
+    public bool FullAuditLogEnabled { get; private set; }
+
+    /// <summary>
+    /// Gets a value indicating whether multi-tenancy is enabled for entities implementing <see cref="ITenantEntity"/>.
+    /// </summary>
+    public bool MultiTenancyEnabled { get; private set; }
+
+    /// <summary>
+    /// Gets the type implementing <see cref="IUserProvider"/>.
+    /// </summary>
+    public Type? UserProviderType { get; private set; }
+
+    /// <summary>
+    /// Gets the type implementing <see cref="ITenantProvider"/>.
+    /// </summary>
+    public Type? TenantProviderType { get; private set; }
+
+    /// <summary>
+    /// Gets the threshold for logging slow queries. <c>null</c> disables slow query logging.
+    /// </summary>
+    public TimeSpan? SlowQueryThreshold { get; private set; }
+
+    /// <summary>
+    /// Enables soft delete for entities implementing <see cref="ISoftDeletable"/>.
+    /// </summary>
+    /// <param name="cascade">Whether to enable cascade soft delete for related entities.</param>
+    /// <returns>This instance for chaining.</returns>
+    public EfCoreKitOptions EnableSoftDelete(bool cascade = false)
+    {
+        SoftDeleteEnabled = true;
+        CascadeSoftDeleteEnabled = cascade;
+        return this;
+    }
+
+    /// <summary>
+    /// Enables audit trail for entities implementing <see cref="IAuditable"/>.
+    /// </summary>
+    /// <param name="fullLog">Whether to enable full change logging to a dedicated audit table.</param>
+    /// <returns>This instance for chaining.</returns>
+    public EfCoreKitOptions EnableAuditTrail(bool fullLog = false)
+    {
+        AuditTrailEnabled = true;
+        FullAuditLogEnabled = fullLog;
+        return this;
+    }
+
+    /// <summary>
+    /// Enables multi-tenancy for entities implementing <see cref="ITenantEntity"/>.
+    /// </summary>
+    /// <returns>This instance for chaining.</returns>
+    public EfCoreKitOptions EnableMultiTenancy()
+    {
+        MultiTenancyEnabled = true;
+        return this;
+    }
+
+    /// <summary>
+    /// Registers the <see cref="IUserProvider"/> implementation to use for audit trail.
+    /// </summary>
+    /// <typeparam name="T">The concrete type implementing <see cref="IUserProvider"/>.</typeparam>
+    /// <returns>This instance for chaining.</returns>
+    public EfCoreKitOptions UseUserProvider<T>() where T : class, IUserProvider
+    {
+        UserProviderType = typeof(T);
+        return this;
+    }
+
+    /// <summary>
+    /// Registers the <see cref="ITenantProvider"/> implementation to use for multi-tenancy.
+    /// </summary>
+    /// <typeparam name="T">The concrete type implementing <see cref="ITenantProvider"/>.</typeparam>
+    /// <returns>This instance for chaining.</returns>
+    public EfCoreKitOptions UseTenantProvider<T>() where T : class, ITenantProvider
+    {
+        TenantProviderType = typeof(T);
+        return this;
+    }
+
+    /// <summary>
+    /// Enables slow query logging for queries exceeding the given threshold.
+    /// </summary>
+    /// <param name="threshold">The duration threshold.</param>
+    /// <returns>This instance for chaining.</returns>
+    public EfCoreKitOptions LogSlowQueries(TimeSpan threshold)
+    {
+        SlowQueryThreshold = threshold;
+        return this;
+    }
+}

src/EfCoreKit.Core/EfCoreKit.Core.csproj

@@ -11,6 +11,7 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.EntityFrameworkCore" />
+    <PackageReference Include="Microsoft.EntityFrameworkCore.Relational" />
   </ItemGroup>
 
 </Project>

src/EfCoreKit.Core/Extensions/DbSetExtensions.cs

@@ -1 +1,77 @@
+using EfCoreKit.Abstractions.Exceptions;
+using Microsoft.EntityFrameworkCore;
 
+namespace EfCoreKit.Core.Extensions;
+
+/// <summary>
+/// Extension methods for <see cref="DbSet{T}"/> providing common query shortcuts.
+/// </summary>
+public static class DbSetExtensions
+{
+    /// <summary>
+    /// Gets an entity by its primary key.
+    /// </summary>
+    /// <typeparam name="T">The entity type.</typeparam>
+    /// <param name="dbSet">The DbSet.</param>
+    /// <param name="id">The primary key value.</param>
+    /// <param name="cancellationToken">A token to cancel the operation.</param>
+    /// <returns>The entity if found; otherwise, <c>null</c>.</returns>
+    public static async Task<T?> GetByIdAsync<T>(
+        this DbSet<T> dbSet,
+        object id,
+        CancellationToken cancellationToken = default) where T : class
+    {
+        return await dbSet.FindAsync([id], cancellationToken);
+    }
+
+    /// <summary>
+    /// Gets an entity by its primary key or throws <see cref="EntityNotFoundException"/>.
+    /// </summary>
+    /// <typeparam name="T">The entity type.</typeparam>
+    /// <param name="dbSet">The DbSet.</param>
+    /// <param name="id">The primary key value.</param>
+    /// <param name="cancellationToken">A token to cancel the operation.</param>
+    /// <returns>The entity.</returns>
+    /// <exception cref="EntityNotFoundException">Thrown when the entity is not found.</exception>
+    public static async Task<T> GetByIdOrThrowAsync<T>(
+        this DbSet<T> dbSet,
+        object id,
+        CancellationToken cancellationToken = default) where T : class
+    {
+        var entity = await dbSet.FindAsync([id], cancellationToken);
+        return entity ?? throw new EntityNotFoundException(typeof(T).Name, id);
+    }
+
+    /// <summary>
+    /// Checks whether an entity with the given primary key exists.
+    /// </summary>
+    /// <typeparam name="T">The entity type.</typeparam>
+    /// <param name="dbSet">The DbSet.</param>
+    /// <param name="id">The primary key value.</param>
+    /// <param name="cancellationToken">A token to cancel the operation.</param>
+    /// <returns><c>true</c> if the entity exists; otherwise, <c>false</c>.</returns>
+    public static async Task<bool> ExistsAsync<T>(
+        this DbSet<T> dbSet,
+        object id,
+        CancellationToken cancellationToken = default) where T : class
+    {
+        var entity = await dbSet.FindAsync([id], cancellationToken);
+        return entity is not null;
+    }
+
+    /// <summary>
+    /// Checks whether any entity matches the given predicate.
+    /// </summary>
+    /// <typeparam name="T">The entity type.</typeparam>
+    /// <param name="dbSet">The DbSet.</param>
+    /// <param name="predicate">The filter predicate.</param>
+    /// <param name="cancellationToken">A token to cancel the operation.</param>
+    /// <returns><c>true</c> if any entity matches; otherwise, <c>false</c>.</returns>
+    public static async Task<bool> ExistsAsync<T>(
+        this DbSet<T> dbSet,
+        System.Linq.Expressions.Expression<Func<T, bool>> predicate,
+        CancellationToken cancellationToken = default) where T : class
+    {
+        return await dbSet.AnyAsync(predicate, cancellationToken);
+    }
+}

src/EfCoreKit.Core/Extensions/ModelBuilderExtensions.cs

@@ -1 +1,45 @@
+using EfCoreKit.Abstractions.Interfaces;
+using Microsoft.EntityFrameworkCore;
 
+namespace EfCoreKit.Core.Extensions;
+
+/// <summary>
+/// Extension methods for <see cref="ModelBuilder"/> to configure EfCoreKit conventions.
+/// </summary>
+public static class ModelBuilderExtensions
+{
+    /// <summary>
+    /// Configures the concurrency token for all entities implementing <see cref="IConcurrencyAware"/>.
+    /// </summary>
+    /// <param name="modelBuilder">The model builder.</param>
+    /// <returns>The model builder for chaining.</returns>
+    public static ModelBuilder ApplyConcurrencyTokens(this ModelBuilder modelBuilder)
+    {
+        // TODO: Iterate entity types implementing IConcurrencyAware
+        // - Configure RowVersion as a concurrency token / row version
+        return modelBuilder;
+    }
+
+    /// <summary>
+    /// Configures soft delete global query filters for all entities implementing <see cref="ISoftDeletable"/>.
+    /// </summary>
+    /// <param name="modelBuilder">The model builder.</param>
+    /// <returns>The model builder for chaining.</returns>
+    public static ModelBuilder ApplySoftDeleteFilters(this ModelBuilder modelBuilder)
+    {
+        // TODO: Delegate to SoftDeleteQueryFilter.Apply
+        return modelBuilder;
+    }
+
+    /// <summary>
+    /// Configures tenant global query filters for all entities implementing <see cref="ITenantEntity"/>.
+    /// </summary>
+    /// <param name="modelBuilder">The model builder.</param>
+    /// <param name="tenantProvider">The tenant provider.</param>
+    /// <returns>The model builder for chaining.</returns>
+    public static ModelBuilder ApplyTenantFilters(this ModelBuilder modelBuilder, ITenantProvider? tenantProvider)
+    {
+        // TODO: Delegate to TenantQueryFilter.Apply
+        return modelBuilder;
+    }
+}