uniq

Documentation

Overview

Package uniq is a utility package that provides common random unique identifiers in UUID, Base32, and n*2 random hexadecimal characters.

6c671957-2f39-4ce5-9f0e-e8d5ec53bfde (16 bytes, 36 chars, hex-)
H6M0STKP0MTSU0493GERQDCSJ5BMF3VO     (20 bytes, 32 chars, base32)
1561158139                           (8 bytes, 10+ chars, int64)
5b ...                               (n bytes, n*2 chars, hex)

When a simple random identifier is all that is needed Base32() provides a better alternative to UUID(). It takes less space (32 characters), is safe for use with all filesystems including case-insensitive ones, and provides additional randomness increased from 2^128 (uuid) to 2^160 (base32).

This package includes the following convenience commands as well for use when integrating with shell scripts:

uuid
uid32
epoch [SECONDS]
randhex [COUNT]

Index

• func Base32() string
• func Bytes(n int) []byte
• func Hex(n int) string
• func Second() string
• func UUID() string

Functions

func Base32

func Base32() string

Base32 returns a base32 encoded 20 byte string. This has a greater range than UUID() and is safe for use with filesystems. Base32 is rendered in uppercase for clarity and because it is case insensitive. Base32 depends on 40 bit chunks. 20 bytes exceeds UUID() randomness and is the closest. (15 would be insufficient to cover the same range.) Base32() is therefore superior to UUID() both in range of randomness and practicality. Returns an empty string if unable to read random data.

func Bytes

func Bytes(n int) []byte

Bytes returns n number of cryptographically secure pseudo-random bytes or a zero length slice if unable to read them from the hosting device.

func Hex

func Hex(n int) string

Hex returns a random hexadecimal string that is n*2 characters in length. Calling Hex(18) is superior to UUID() and fits into the same 36 character space. Base32() remains superior, but sometimes content limitations and validators require only hexadecimal characters. Hex() can also be used to generate random RGB colors with Hex(3). Returns empty string if unable to read random data from host device.

func Second

func Second() string

Second returns the current (time.Unix()) second since Jan 1, 1970 UTC. This is frequently a very good unique suffix that has the added advantage of being chronologically sortable.

func UUID

func UUID() string

UUID returns a standard UUID v4 according to RFC 4122. UUIDs have become deeply entrenched universally but are inferior to Base32 as the need for a greater range of randomness emerges (IPv6, etc.) Returns empty string if unable to read random data for any reason.