Save the planet, recycle your guids!

GuidRecycler is a library that allows you to recycle guids. It is a simple concept.

GuidRecycler is available as a NuGet package.

Install-Package GuidRecycler

Guid recyclers implement the common interface IGuidRecycler which has the following methods:

void Recycle(Guid guid);

To recycle a guid to the recycle bin.

Guid GetGuid();

To retrieve a recycled (or new) guid.

There are curently two strategies implemented:

• ConcurrentGuidRecycler
  A robust thread-safe concurrent guid recycler.
• GuidRecyclerSlim
  A non-thread-safe guid recycler that is faster than the concurrent guid recycler.

The guid recycler can be created manually or retrieved through dependency injection.

class UserService
{
    private readonly DatabaseContext _context;
    private readonly IGuidRecycler recycler = new GuidRecyclerSlim();

    public async Task DeleteUser(User user)
    {
        _context.Users.Remove(user);
        recycler.Recycle(user.Id);
        await _context.SaveChangesAsync();
    }

    public async Task<User> CreateUser(string name)
    {
        var user = new User
        {
            Id = recycler.GetGuid(),
            Name = name
        };
        _context.Users.Add(user);
        await _context.SaveChangesAsync();
        return user;
    }

As you can see, this code is very simple and eco-friendly. The only thing you need to do is to recycle the guid when you delete the entity and to get a new guid when you create a new entity.

Coming soon

See the benchmarks in the benchmarks folder. It clearly shows that the both the concurrent guid recycler and the guid recycler slim are faster than the default guid generator.

PRs welcome. Merging not guaranteed.