README.md

Specification design pattern

In computer programming, the specification pattern is a particular software design pattern, whereby business rules can be recombined by chaining the business rules together using boolean logic. The pattern is frequently used in the context of domain-driven design.Wiki

How to use

Create a new specification class for a given entity

public class GetItemsByListId : Specification<TodoItem>
{
    public GetItemsByListId(Guid listId) : base(item => item.ListId == listId)
    {
        AddOrderBy(s => s.DueTo);
    }
}

Then use it

using var context = new AppDbContext();
var itemRepository = new Repository<TodoItem>(context);

var firstListItems = itemRepository.Apply(new GetItemsByListId("<input-id-here>"));