Overview

• WUID is a universal unique identifier generator.
• WUID is much faster than traditional UUID. Each WUID instance can even generate 100M unique identifiers in a single second.
• In the nutshell, WUID generates 64-bit integers in sequence. The high 28 bits are loaded from a data source. By now, Redis, MySQL, MongoDB and Callback are supported.
• The uniqueness is guaranteed as long as all WUID instances share a same data source or each group of them has a different section ID.
• WUID automatically renews the high 28 bits when the low 36 bits are about to run out.
• WUID is thread-safe, and lock free.
• Obfuscation is supported.

Benchmarks

BenchmarkWUID           159393580          7.661 ns/op        0 B/op       0 allocs/op
BenchmarkRand           100000000         14.95 ns/op         0 B/op       0 allocs/op
BenchmarkTimestamp      164224915          7.359 ns/op        0 B/op       0 allocs/op
BenchmarkUUID_V1        23629536          43.42 ns/op         0 B/op       0 allocs/op
BenchmarkUUID_V2        29351550          43.96 ns/op         0 B/op       0 allocs/op
BenchmarkUUID_V3         4703044         254.2 ns/op        144 B/op       4 allocs/op
BenchmarkUUID_V4         5796310         210.0 ns/op         16 B/op       1 allocs/op
BenchmarkUUID_V5         4051291         310.7 ns/op        168 B/op       4 allocs/op
BenchmarkRedis              2996       38725 ns/op          160 B/op       5 allocs/op
BenchmarkSnowflake       1000000        2092 ns/op            0 B/op       0 allocs/op
BenchmarkULID            5660170         207.7 ns/op         16 B/op       1 allocs/op
BenchmarkXID            49639082          26.21 ns/op         0 B/op       0 allocs/op
BenchmarkShortID         1312386         922.2 ns/op        320 B/op      11 allocs/op
BenchmarkKsuid          19717675          59.79 ns/op         0 B/op       0 allocs/op

Getting Started

go get -u github.com/edwingeng/wuid

Usages

Redis

import "github.com/edwingeng/wuid/redis/v8/wuid"

newClient := func() (redis.UniversalClient, bool, error) {
    var client redis.UniversalClient
    // ...
    return client, true, nil
}

// Setup
w := NewWUID("alpha", nil)
err := w.Loadh32FromRedis(newClient, "wuid")
if err != nil {
    panic(err)
}

// Generate
for i := 0; i < 10; i++ {
    fmt.Printf("%#016x\n", w.Next())
}

MySQL

import "github.com/edwingeng/wuid/mysql/wuid"

openDB := func() (*sql.DB, bool, error) {
    var db *sql.DB
    // ...
    return db, true, nil
}

// Setup
w := NewWUID("alpha", nil)
err := w.Loadh32FromMysql(openDB, "wuid")
if err != nil {
    panic(err)
}

// Generate
for i := 0; i < 10; i++ {
    fmt.Printf("%#016x\n", w.Next())
}

MongoDB

import "github.com/edwingeng/wuid/mongo/wuid"

newClient := func() (*mongo.Client, bool, error) {
    var client *mongo.Client
    // ...
    return client, true, nil
}

// Setup
w := NewWUID("alpha", nil)
err := w.Loadh32FromMongo(newClient, "test", "wuid", "default")
if err != nil {
    panic(err)
}

// Generate
for i := 0; i < 10; i++ {
    fmt.Printf("%#016x\n", w.Next())
}

Callback

import "github.com/edwingeng/wuid/callback/wuid"

callback := func() (int64, func(), error) {
    var h32 int64
    // ...
    return h32, nil, nil
}

// Setup
w := NewWUID("alpha", nil)
err := w.Loadh32WithCallback(callback)
if err != nil {
    panic(err)
}

// Generate
for i := 0; i < 10; i++ {
    fmt.Printf("%#016x\n", w.Next())
}

Mysql Table Creation

CREATE TABLE IF NOT EXISTS `wuid` (
    `h` int(10) NOT NULL AUTO_INCREMENT,
    `x` tinyint(4) NOT NULL DEFAULT '0',
    PRIMARY KEY (`x`),
    UNIQUE KEY `h` (`h`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1;

Options

• WithSection brands a section ID on each generated number. A section ID must be in between [0, 7].
• WithStep sets the step and the floor for each generated number.
• WithObfuscation enables number obfuscation.

Attentions

It is highly recommended to pass a logger to wuid.NewWUID and keep an eye on the warnings that include "renew failed". It indicates that the low 36 bits are about to run out in hours to hundreds of hours, and the renewal program failed for some reason. WUID will make many renewal attempts until succeeded.

Special thanks

• dustinfog

Ports

• swift - https://github.com/ekscrypto/SwiftWUID