Application Architecture - Repository

It is a good practice to separate business logic and data handling. Entity Framework provides an MVC pattern to separate them. However, as the size of a project grows, adding data handling codes directly in the controller file creates duplicate codes and becomes hard to test. A repository pattern is a design pattern that reduces duplication and makes testing easier. Let's see how we can implement a repository pattern in this writing

Project Configurations

Creating a Project with MVC Pattern

Server Architecture - Distributing Projects

Implementing MVC Pattern

Application Architecture - MVC

Repository Pattern Configuration

Creating Repository

Add a repository class under the infrastructure folder

Add constructor and inject context

private readonly StoreContext _context;
public ItemRepo(StoreContext context)
{
  this._context = context;
}

Add desired methods to handle data

public List<Item> GetItems()
{
  return _context.Items.ToList();
}

Calling Repository Method in the Controller Class

In a normal MVC pattern, controllers access the context directly as shown below.

To use the repository, delete the context and inject the repository

private readonly ItemRepo _repo;
public StoreController(ItemRepo repo)
{
  this._repo = repo;
}

Call the method in the HTTP request

[HttpGet]
public ActionResult<List<Item>> GetItems()
{
  return _repo.GetItems();
}

In this writing, we have seen how we can use the MVC repository pattern in .NET with EntityFramework