correlation/base62.go

package correlation

import "bytes"

const base62Chars string = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"

// encodeReverseBase62 encodes num into its Base62 reversed representation.
// The most significant value is at the end of the string.
//
// Appending is faster than prepending and this is enough for the purpose of a random ID.
func encodeReverseBase62(num int64) string {
	if num == 0 {
		return "0"
	}

	encoded := bytes.Buffer{}
	for q := num; q > 0; q /= 62 {
		encoded.Write([]byte{base62Chars[q%62]})
	}

	return encoded.String()
}