CVAMF.Repository 1.0.0

CVAMF.Repository

Generic Repository Pattern implementation for Entity Framework Core with support for filters, pagination, and multiple primary key types.

Features

• ✅ Generic Repository Pattern for EF Core
• ✅ Support for Guid and Int primary keys
• ✅ Filtering with Expression Functions
• ✅ Optional pagination
• ✅ Full CRUD operations
• ✅ Async/await support
• ✅ Easy dependency injection integration
• ✅ .NET 10 compatible

Installation

dotnet add package CVAMF.Repository

Or via NuGet Package Manager:

Install-Package CVAMF.Repository

Quick Start

1. Create your entities

For Guid primary key (recommended):

using CVAMF.Repository.Entities;

public class Product : EntityBase
{
    public string Name { get; set; } = string.Empty;
    public string Description { get; set; } = string.Empty;
    public decimal Price { get; set; }
    public int Stock { get; set; }
    public bool IsActive { get; set; }
    public string Category { get; set; } = string.Empty;
    public DateTime CreatedAt { get; set; }
}

For Int primary key:

using CVAMF.Repository.Entities;

public class Category : EntityBaseInt
{
    public string Name { get; set; } = string.Empty;
    public string Description { get; set; } = string.Empty;
    public bool IsActive { get; set; }
}

Custom entity implementing IEntity<T>:

using CVAMF.Repository.Entities;

public class Order : IEntity<Guid>
{
    public Guid Id { get; set; }
    public string OrderNumber { get; set; } = string.Empty;
    public decimal TotalAmount { get; set; }
    public DateTime OrderDate { get; set; }
    public string Status { get; set; } = string.Empty;
}

2. Configure your DbContext

using Microsoft.EntityFrameworkCore;

public class ApplicationDbContext : DbContext
{
    public ApplicationDbContext(DbContextOptions<ApplicationDbContext> options)
        : base(options)
    {
    }

    public DbSet<Product> Products { get; set; }
    public DbSet<Category> Categories { get; set; }
    public DbSet<Order> Orders { get; set; }

    protected override void OnModelCreating(ModelBuilder modelBuilder)
    {
        base.OnModelCreating(modelBuilder);

        // Your entity configurations here
        modelBuilder.Entity<Product>(entity =>
        {
            entity.HasKey(e => e.Id);
            entity.Property(e => e.Name).IsRequired().HasMaxLength(200);
            entity.Property(e => e.Price).HasPrecision(18, 2);
        });
    }
}

3. Register services in Program.cs

using CVAMF.Repository.Extensions;
using Microsoft.EntityFrameworkCore;

var builder = WebApplication.CreateBuilder(args);

// Add DbContext
builder.Services.AddDbContext<ApplicationDbContext>(options =>
    options.UseSqlServer(builder.Configuration.GetConnectionString("DefaultConnection")));

// Add repositories - This registers IRepository<,> for all entities!
builder.Services.AddRepositories();

// Add your services
builder.Services.AddScoped<ProductService>();
builder.Services.AddScoped<CategoryService>();

var app = builder.Build();
app.Run();

4. Use in your services

using CVAMF.Repository.Interfaces;
using CVAMF.Repository.Models;

public class ProductService
{
    private readonly IRepository<Product, Guid> _productRepository;
    private readonly ILogger<ProductService> _logger;

    public ProductService(
        IRepository<Product, Guid> productRepository,
        ILogger<ProductService> logger)
    {
        _productRepository = productRepository;
        _logger = logger;
    }

    // CRUD operations examples below...
}

Complete Usage Examples

📖 Read Operations

Get by ID

public async Task<Product?> GetProductById(Guid productId)
{
    var product = await _productRepository.GetByIdAsync(productId);

    if (product == null)
    {
        _logger.LogWarning("Product {ProductId} not found", productId);
        return null;
    }

    return product;
}

Get All

public async Task<IEnumerable<Product>> GetAllProducts()
{
    return await _productRepository.GetAllAsync();
}

Simple Filter

public async Task<IEnumerable<Product>> GetActiveProducts()
{
    return await _productRepository.GetAsync(
        filter: p => p.IsActive);
}

Filter with Ordering

public async Task<IEnumerable<Product>> GetProductsByCategory(string category)
{
    return await _productRepository.GetAsync(
        filter: p => p.Category == category && p.IsActive,
        orderBy: q => q.OrderBy(p => p.Name));
}

Complex Filters

public async Task<IEnumerable<Product>> GetProductsInPriceRange(
    decimal minPrice, 
    decimal maxPrice, 
    string? searchTerm = null)
{
    return await _productRepository.GetAsync(
        filter: p => p.IsActive 
                  && p.Price >= minPrice 
                  && p.Price <= maxPrice
                  && (searchTerm == null || p.Name.Contains(searchTerm) || p.Description.Contains(searchTerm)),
        orderBy: q => q.OrderBy(p => p.Price).ThenBy(p => p.Name));
}

Multiple Sorting

public async Task<IEnumerable<Product>> GetProductsSorted()
{
    return await _productRepository.GetAsync(
        filter: p => p.Stock > 0,
        orderBy: q => q.OrderBy(p => p.Category)
                       .ThenByDescending(p => p.Price)
                       .ThenBy(p => p.Name));
}

📄 Pagination Examples

Basic Pagination

public async Task<PagedResult<Product>> GetProductsPaged(int pageNumber, int pageSize)
{
    return await _productRepository.GetPagedAsync(
        pageNumber: pageNumber,
        pageSize: pageSize,
        filter: p => p.IsActive,
        orderBy: q => q.OrderBy(p => p.Name));
}

Advanced Pagination with Search

public async Task<PagedResult<Product>> SearchProducts(
    string searchTerm,
    int page = 1,
    int pageSize = 10,
    string sortBy = "name",
    bool descending = false)
{
    var pagedResult = await _productRepository.GetPagedAsync(
        pageNumber: page,
        pageSize: pageSize,
        filter: p => p.IsActive && (
            p.Name.Contains(searchTerm) ||
            p.Description.Contains(searchTerm) ||
            p.Category.Contains(searchTerm)
        ),
        orderBy: sortBy.ToLower() switch
        {
            "price" => descending 
                ? q => q.OrderByDescending(p => p.Price)
                : q => q.OrderBy(p => p.Price),
            "date" => descending
                ? q => q.OrderByDescending(p => p.CreatedAt)
                : q => q.OrderBy(p => p.CreatedAt),
            _ => descending
                ? q => q.OrderByDescending(p => p.Name)
                : q => q.OrderBy(p => p.Name)
        });

    _logger.LogInformation(
        "Found {TotalCount} products. Showing page {Page} of {TotalPages}",
        pagedResult.TotalCount,
        pagedResult.PageNumber,
        pagedResult.TotalPages);

    return pagedResult;
}

Display Pagination Info

public async Task DisplayProductsPaged()
{
    var pagedResult = await _productRepository.GetPagedAsync(
        pageNumber: 1,
        pageSize: 10,
        filter: p => p.IsActive);

    Console.WriteLine($"Page {pagedResult.PageNumber} of {pagedResult.TotalPages}");
    Console.WriteLine($"Total items: {pagedResult.TotalCount}");
    Console.WriteLine($"Items per page: {pagedResult.PageSize}");
    Console.WriteLine($"Has previous: {pagedResult.HasPreviousPage}");
    Console.WriteLine($"Has next: {pagedResult.HasNextPage}");
    Console.WriteLine();

    foreach (var product in pagedResult.Items)
    {
        Console.WriteLine($"- {product.Name} (${product.Price})");
    }
}

✏️ Create Operations

Add Single Entity

public async Task<Product> CreateProduct(string name, decimal price, string category)
{
    var product = new Product
    {
        Id = Guid.NewGuid(),
        Name = name,
        Price = price,
        Category = category,
        IsActive = true,
        Stock = 0,
        CreatedAt = DateTime.UtcNow
    };

    await _productRepository.AddAsync(product);
    await _productRepository.SaveChangesAsync();

    _logger.LogInformation("Product {ProductName} created with ID {ProductId}", 
        product.Name, product.Id);

    return product;
}

Add Multiple Entities

public async Task<int> ImportProducts(List<ProductDto> productDtos)
{
    var products = productDtos.Select(dto => new Product
    {
        Id = Guid.NewGuid(),
        Name = dto.Name,
        Price = dto.Price,
        Category = dto.Category,
        IsActive = true,
        Stock = dto.Stock,
        CreatedAt = DateTime.UtcNow
    }).ToList();

    await _productRepository.AddRangeAsync(products);
    var savedCount = await _productRepository.SaveChangesAsync();

    _logger.LogInformation("Imported {Count} products", savedCount);

    return savedCount;
}

🔄 Update Operations

Update Single Entity

public async Task<bool> UpdateProductPrice(Guid productId, decimal newPrice)
{
    var product = await _productRepository.GetByIdAsync(productId);

    if (product == null)
    {
        _logger.LogWarning("Product {ProductId} not found", productId);
        return false;
    }

    product.Price = newPrice;

    await _productRepository.UpdateAsync(product);
    await _productRepository.SaveChangesAsync();

    _logger.LogInformation("Product {ProductId} price updated to {Price}", 
        productId, newPrice);

    return true;
}

Update Multiple Entities

public async Task<int> ApplyDiscountToCategory(string category, decimal discountPercent)
{
    var products = await _productRepository.GetAsync(
        filter: p => p.Category == category && p.IsActive);

    foreach (var product in products)
    {
        product.Price = product.Price * (1 - discountPercent / 100);
    }

    await _productRepository.UpdateRangeAsync(products);
    var updatedCount = await _productRepository.SaveChangesAsync();

    _logger.LogInformation(
        "Applied {Discount}% discount to {Count} products in category {Category}",
        discountPercent, updatedCount, category);

    return updatedCount;
}

Conditional Update

public async Task<int> DeactivateLowStockProducts()
{
    var lowStockProducts = await _productRepository.GetAsync(
        filter: p => p.Stock < 5 && p.IsActive);

    foreach (var product in lowStockProducts)
    {
        product.IsActive = false;
    }

    await _productRepository.UpdateRangeAsync(lowStockProducts);
    return await _productRepository.SaveChangesAsync();
}

🗑️ Delete Operations

Delete by ID

public async Task<bool> DeleteProduct(Guid productId)
{
    var product = await _productRepository.GetByIdAsync(productId);

    if (product == null)
    {
        return false;
    }

    await _productRepository.DeleteAsync(productId);
    await _productRepository.SaveChangesAsync();

    _logger.LogInformation("Product {ProductId} deleted", productId);

    return true;
}

Delete by Entity

public async Task DeleteInactiveProduct(string productName)
{
    var product = await _productRepository.GetFirstOrDefaultAsync(
        filter: p => p.Name == productName && !p.IsActive);

    if (product != null)
    {
        await _productRepository.DeleteAsync(product);
        await _productRepository.SaveChangesAsync();
    }
}

Delete Multiple Entities

public async Task<int> CleanupOldInactiveProducts(int daysOld)
{
    var cutoffDate = DateTime.UtcNow.AddDays(-daysOld);

    var oldProducts = await _productRepository.GetAsync(
        filter: p => !p.IsActive && p.CreatedAt < cutoffDate);

    if (oldProducts.Any())
    {
        await _productRepository.DeleteRangeAsync(oldProducts);
        var deletedCount = await _productRepository.SaveChangesAsync();

        _logger.LogInformation("Deleted {Count} old inactive products", deletedCount);
        return deletedCount;
    }

    return 0;
}

🔍 Query Helper Methods

Check Existence

public async Task<bool> ProductExists(string name)
{
    return await _productRepository.AnyAsync(
        filter: p => p.Name == name);
}

public async Task<bool> HasProductsInCategory(string category)
{
    return await _productRepository.AnyAsync(
        filter: p => p.Category == category && p.IsActive);
}

Count

public async Task<int> GetTotalProducts()
{
    return await _productRepository.CountAsync();
}

public async Task<int> GetActiveProductCount()
{
    return await _productRepository.CountAsync(
        filter: p => p.IsActive);
}

public async Task<Dictionary<string, int>> GetProductCountByCategory()
{
    var categories = await _productRepository.GetAsync(
        filter: p => p.IsActive);

    return categories
        .GroupBy(p => p.Category)
        .ToDictionary(g => g.Key, g => g.Count());
}

First or Default

public async Task<Product?> GetMostExpensiveProduct()
{
    var products = await _productRepository.GetAsync(
        filter: p => p.IsActive,
        orderBy: q => q.OrderByDescending(p => p.Price));

    return products.FirstOrDefault();
}

public async Task<Product?> FindProductByName(string name)
{
    return await _productRepository.GetFirstOrDefaultAsync(
        filter: p => p.Name == name && p.IsActive);
}

Using with Int Primary Keys

public class CategoryService
{
    private readonly IRepository<Category, int> _categoryRepository;

    public CategoryService(IRepository<Category, int> categoryRepository)
    {
        _categoryRepository = categoryRepository;
    }

    public async Task<Category> CreateCategory(string name)
    {
        var category = new Category
        {
            // No need to set Id for int (auto-increment)
            Name = name,
            IsActive = true
        };

        await _categoryRepository.AddAsync(category);
        await _categoryRepository.SaveChangesAsync();

        return category;
    }

    public async Task<Category?> GetCategoryById(int categoryId)
    {
        return await _categoryRepository.GetByIdAsync(categoryId);
    }
}

Advanced Scenarios

Transaction Example

public async Task<bool> TransferStock(Guid fromProductId, Guid toProductId, int quantity)
{
    var fromProduct = await _productRepository.GetByIdAsync(fromProductId);
    var toProduct = await _productRepository.GetByIdAsync(toProductId);

    if (fromProduct == null || toProduct == null || fromProduct.Stock < quantity)
    {
        return false;
    }

    try
    {
        fromProduct.Stock -= quantity;
        toProduct.Stock += quantity;

        await _productRepository.UpdateAsync(fromProduct);
        await _productRepository.UpdateAsync(toProduct);

        // Both updates are saved in a single transaction
        await _productRepository.SaveChangesAsync();

        return true;
    }
    catch (Exception ex)
    {
        _logger.LogError(ex, "Error transferring stock");
        return false;
    }
}

Working with DTOs

public async Task<List<ProductListDto>> GetProductList(string category)
{
    var products = await _productRepository.GetAsync(
        filter: p => p.Category == category && p.IsActive,
        orderBy: q => q.OrderBy(p => p.Name));

    return products.Select(p => new ProductListDto
    {
        Id = p.Id,
        Name = p.Name,
        Price = p.Price,
        InStock = p.Stock > 0
    }).ToList();
}

Soft Delete Pattern

// Add DeletedAt property to your entity
public class Product : EntityBase
{
    public string Name { get; set; } = string.Empty;
    public decimal Price { get; set; }
    public bool IsActive { get; set; }
    public DateTime? DeletedAt { get; set; }
}

// Implement soft delete
public async Task SoftDeleteProduct(Guid productId)
{
    var product = await _productRepository.GetByIdAsync(productId);

    if (product != null)
    {
        product.DeletedAt = DateTime.UtcNow;
        product.IsActive = false;

        await _productRepository.UpdateAsync(product);
        await _productRepository.SaveChangesAsync();
    }
}

// Get only non-deleted products
public async Task<IEnumerable<Product>> GetActiveNonDeletedProducts()
{
    return await _productRepository.GetAsync(
        filter: p => p.IsActive && p.DeletedAt == null);
}

Best Practices

✅ DO

• Always call SaveChangesAsync() after Add, Update, or Delete operations
• Use pagination for large datasets
• Use specific filters to reduce database load
• Handle null returns from GetByIdAsync and GetFirstOrDefaultAsync
• Use CancellationToken for long-running operations
• Inject IRepository<TEntity, TKey> instead of concrete implementations

❌ DON'T

• Don't forget to call SaveChangesAsync() - changes won't persist!
• Don't load all data without filters unless necessary
• Don't use magic strings - use constants or enums
• Don't ignore exceptions - always log and handle errors

API Reference

Query Methods

Command Methods

Requirements

• .NET 10.0 or higher
• Entity Framework Core 10.0 or higher

License

MIT

Author

Carlos Filho

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

Support

If you encounter any issues or have questions, please file an issue on the GitHub repository.