UID64

This uid64 package generates 64bit unique identifier, which is Sortable, Clock and Random number-based. Especially, UID can be DB's primary key as long-int(int64) directly.

This package is greatly inspired by go-scru128 and google/uuid. ( But it does NOT follow any RFC specification. )

If you like this package's feature but need more powerful facilities, consider to use go-scru128. It is awesome write up about UUID.

Usage

// Create a NewGenerator with a id that must be in rage 0~3.
g, err := NewGenerator(0)
handle(err)

// Call Gen() for thread-safe generation.
id1, err := g.Gen()
// Call GenDanger() for NOT thread-safe generation.
id2, err := g.GenDanger()

instance := Instance{id1, "test"}

// UID implements sql.Valuer, 
// it can be inserted to sql DB directly, 
// and can be ordered primary key as Long-Int(64bit).
err := db.Save(instance) 
handle(err)

// UID implements sql.Scanner,
// it also can be loaded from DB directly.

Features

Cases this repository is for

• Need Sortable, Clock, Random Unique Indentifier
• Need DB Insertion friendly ID ( orederd, native Long-Int)
• Want short string representation (Base36)
• Want Thread-safe, Unieque ID over all generators (up to 4)

Cases it's NOT for

• Will generate more than 128 per a milli-sec.
• Want more than 4 distributed generators.
• Want to follow RFC.

Benchmarks

With my laptop comparing ID-generation to google's UUID library, this repository is

• more than 5x faster
• 16x smaller allocation size
• same allocation count (1 times)

goos: linux
goarch: amd64
pkg: github.com/hitoshi44/go-uid64
cpu: AMD Ryzen 5 3500U with Radeon Vega Mobile Gfx  
BenchmarkGoogleUUIDNew-8   	 1963202	       621.9 ns/op	      16 B/op	       1 allocs/op
PASS
ok  	github.com/hitoshi44/go-uid64	1.813s

goos: linux
goarch: amd64
pkg: github.com/hitoshi44/go-uid64
cpu: AMD Ryzen 5 3500U with Radeon Vega Mobile Gfx  
BenchmarkUID64Gen-8   	 8579986	       122.7 ns/op	       1 B/op	       1 allocs/op
PASS
ok  	github.com/hitoshi44/go-uid64	1.206s