# README

shortuuid

A Go library that generates concise, unambiguous, URL-safe UUIDs. Based on and compatible with the Python library shortuuid.

Often, one needs to use non-sequential IDs in places where users will see them, but the IDs must be as concise and easy to use as possible. shortuuid solves this problem by generating UUIDs using google/uuid and then translating them to base57 using lowercase and uppercase letters and digits, and removing similar-looking characters such as l, 1, I, O and 0.

Usage

package main

import (
    "fmt"

    "github.com/lithammer/shortuuid/v3"
)

func main() {
    u := shortuuid.New() // Cekw67uyMpBGZLRP2HFVbe
}

To use UUID v5 (instead of the default v4), use NewWithNamespace(name string) instead of New().

shortuuid.NewWithNamespace("http://example.com")

It's possible to use a custom alphabet as well, though it has to be 57 characters long.

alphabet := "23456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxy="
shortuuid.NewWithAlphabet(alphabet) // u=BFWRLr5dXbeWf==iasZi

Bring your own encoder! For example, base58 is popular among bitcoin.

package main

import (
    "fmt"
    "github.com/btcsuite/btcutil/base58"
    "github.com/lithammer/shortuuid/v3"
    "github.com/satori/go.uuid"
)

type base58Encoder struct {}

func (enc base58Encoder) Encode(u uuid.UUID) string {
    return base58.Encode(u.Bytes())
}

func (enc base58Encoder) Decode(s string) (uuid.UUID, error) {
    return uuid.FromBytes(base58.Decode(s))
}

func main() {
    enc := base58Encoder{}
    fmt.Println(shortuuid.NewWithEncoder(enc)) // 6R7VqaQHbzC1xwA5UueGe6
}