GuidRecycler

Save the planet, recycle your guids!

What is it?

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

Installation

GuidRecycler is available as a NuGet package.

Install-Package GuidRecycler

Usage:

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.

Strategies

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.

Example

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.

Microsoft.Extensions.DependencyInjection

Coming soon

Performance

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.

Method	Mean	Error	StdDev	Median	Ratio	RatioSD	Allocated	Alloc Ratio
Guid.NewGuid	647.9 ns	113.68 ns	327.99 ns	600.0 ns	1.00	0.00	600 B	1.00
ConcurrentGuidRecycler	307.1 ns	49.97 ns	146.56 ns	300.0 ns	0.58	0.39	600 B	1.00
GuidRecyclerSlim	224.0 ns	28.33 ns	81.75 ns	200.0 ns	0.45	0.30	600 B	1.00

Contributing

PRs welcome. Merging not guaranteed.