go-nanoid

This module is a Go implementation of nanoid.

Features of the nanoid spec are:

• URL friendly
• Use of hardware random generator
• Uses a bigger alphabet than UUID, so a similar number of random bits are packed in just 21 chars instead of 36 (like UUID)
• Much, much faster than UUID (v4)

Features of this specific implementation are:

• Fastest and most performant implementation of Nano ID around (benchmarks)
• Prefetches random bytes in advance
• Uses optimal memory
• No production dependencies

Security

See comparison of Nano ID and UUID (V4):

"Nano ID is quite comparable to UUID v4 (random-based). It has a similar number of random bits in the ID (126 in Nano ID and 122 in UUID), so it has a similar collision probability -- for there to be a one in a billion chance of duplication, 103 trillion version 4 IDs must be generated"

And NanoID collision calculator:

If 1,000,000 Nano IDs (using nanoid.Standard(21)) were generated each second, it would require ~41 thousand years in order to have a 1% probability of a collision

In other words, with 21 characters, the total number of possible unique IDs would be 21^64, which is ~four septenvigintillion (4 followed by 84 zeros) -- a figure larger than the number of atoms that exist in the universe, apparently

Read more here

Example

import (
	"log"
	"math/rand"
	"time"
	"github.com/jaevor/go-nanoid"
)

func main() {
  createNanoid, err := nanoid.Standard(21)
  if err != nil {
    panic(err)
  }

  id1 := createNanoid()
  log.Printf("ID 1: %s", id1) // Sk4rC4fjsRm-LS1gtbL1y

  // [!] Remember to seed. 
  rand.Seed(time.Now().Unix())

  createNonSecureNanoid, err := nanoid.StandardNonSecure(21)
  if err != nil {
    panic(err)
  }

  id2 := createNonSecureNanoid()
  log.Printf("ID 2: %s", id2) // japKZqwnQvllgUQ8lwgkP

  createCustomNanoid, err := nanoid.Custom("0123456789", 12)
  if err != nil {
    panic(err)
  }

  id3 := createCustomNanoid()
  log.Printf("ID 3: %s", id3) // 462855288020
}

Notes

Might remove all non-secure Nano ID generators in the future. The benefit of the trade-off between using them and not the secure ones should be speed, but I can't figure out how to get PRNG fast

Remember to rand.Seed(...) before using the non-secure generators

In terms of speed & efficiency, it is probably always better to use Standard Nano ID than any Custom

Benchmarks

All benchmarks & tests can be found in nanoid_test.go.

These are all benchmarks of the Standard Nano ID generator

Credits & references

License

MIT License