Nanis.RepositoryCriteria.EntityFrameworkCore 1.1.0

Nanis Repository Library

Nanis.RepositoryCriteria.EntityFrameworkCore is a library designed to implement an abstraction of the Repository pattern using Entity Framework. This library also implements the Unit of Work pattern to manage database transactions and commits, and the Criteria pattern to build complex queries with logical operators and criteria composition.

Key Features

• Repository Pattern: Provides an abstraction for data access using Entity Framework, enabling operations such as Create, Read, Update, and Delete.
• Unit of Work Pattern: Manages transactions centrally, allowing commits or rollbacks of changes to the database.
• Criteria Pattern: Allows building dynamic and robust queries with filters, sorting, pagination, and entity relationships.

Installation

Using NuGet

You can install this library directly from NuGet into your .NET project by running the following command:

dotnet add package Nanis.RepositoryCriteria.EntityFrameworkCore

Manual Installation

git clone https://github.com/cacuellarh/Nanis.RepositoryCriteria.EntityFrameworkCore-

Usage

dependencies

//Register the current Dbcontenttext in a container
services.AddDbContext<MyDbContext>(options =>
	options.UseInMemoryDatabase("MyDatabase"));

//Registering the Repository Factory
//An instance of IRepositoryFactory is registered, which is responsible for creating repositories. 
//It uses the current assembly and the DbContext to configure the factory.

services.AddSingleton<IRepositoryFactory>(provider =>
    {
        var currentAssembly = Assembly.GetExecutingAssembly();
        var dbContext = provider.GetRequiredService<MyDbContext>();
        return new RepositoryFactory(currentAssembly, dbContext);
    });

//Registering the Unit of Work Pattern
services.AddTransient<IUnitOfWork>(provider => {
    var dbContext = provider.GetRequiredService<MyDbContext>();
    var factory = provider.GetRequiredService<IRepositoryFactory>();
    return new UnitOfWork(dbContext, factory);
});

Creating a New Entity and repository

public class Product
{
    public int Id { get; set; }
    public string Name { get; set; }
    public string Description { get; set; }
    public int CategoryId { get; set; }
    public int LocationId { get; set; }
    public Category Category { get; set; }
    public Location Location { get; set; }
}

public interface IProductRepository : IRepository<Product>
{ 
    
}

public class ProductRepository : Repository<Product>, IProductRepository
{
    public ProductRepository(DbContext context) : base(context)
    {
    }
}

public class Location
{
    public int Id { get; set; }
    public string City { get; set; }
    public string Country { get; set; }
}

public class Category
{
    public int Id { get; set; }
    public string Name { get; set; }
}

Defining Criteria for Product Query

    
public class ProductByCountryCriteria : Criteria<Product>
{
    public ProductByCountryCriteria(string country)
    {
        AddCriteria(p => p.Location.Country == country);

    }
}

public class ProductByNameCriteria : Criteria<Product>
{
    public ProductByNameCriteria(string productName)
    {
        AddCriteria(p => p.Name == productName);
        
    }
}

public class ProductByNameAndCountry : Criteria<Product>
{
    public ProductByNameAndCountry(string name, string country)
    {
        AddCriteria(new ProductByNameCriteria(name).GetCriteria);
        And(new ProductByCountryCriteria(country).GetCriteria);
        AddInclude(
            q => q.Include(p => p.Location),
            q => q.Include(p => p.Category)
        );
        Select(p => new { description = p.Description, name = p.Name });

    }
}

Complete example of how to use unit of work, repository and criteria application

// Retrieves an instance of IUnitOfWork from the service provider.
// The Unit of Work pattern is used to manage transactions across multiple operations,
// allowing changes to be committed or rolled back as a single unit.
var unitOfWork = serviceProvider.GetRequiredService<IUnitOfWork>();

// Retrieves the Product repository from the Unit of Work instance.
// This repository will be used to handle data access specifically for Product entities.
var productRepository = unitOfWork.Repository<Product, IProductRepository>();

// Creates a new Product entity with specific properties.
var newProduct = new Product
{
    Id = 4,
    Name = "Product D",
    CategoryId = 1,
    LocationId = 1,
    Description = "Description of Product D",
};

// Asynchronously adds the new product to the repository.
await productRepository.CreateAsync(newProduct);

// Commits all changes made within the current unit of work to the database.
await unitOfWork.Commit();

// Creates a criteria to filter products by the country "USA".
var productCriteria = new ProductByCountryCriteria("USA");

// Retrieves all products that match the specified criteria asynchronously.
var products = await productRepository.GetAllAsync(productCriteria);

// Creates a combined criteria to filter products by both name and country.
var productCombinedCriterias = new ProductByNameAndCountry("Product D", "USA");

// Retrieves a single product that matches the combined criteria,
// with a projection to select specific fields.
var productDto = await productRepository.GetAsyncWithProyection(productCombinedCriterias);

Contributing

If you want to contribute to this project, please follow these steps:

Fork the repository. Create a branch for your changes. Submit a pull request with a detailed description of the changes.