Generate UUID v1

Generate a time-based UUID v1 using timestamp and random node ID.

Code

Utilities

require 'securerandom'
now = Time.now
time_greg = (now.to_f * 10_000_000).to_i + 0x01b21dd213814000
time_low = (time_greg & 0xffffffff).to_s(16).rjust(8, '0')
time_mid = ((time_greg >> 32) & 0xffff).to_s(16).rjust(4, '0')
time_hi = (((time_greg >> 48) & 0x0fff) | 0x1000).to_s(16).rjust(4, '0')
clock_seq = (SecureRandom.random_number(0x3fff) | 0x8000).to_s(16).rjust(4, '0')
node = SecureRandom.hex(6)
return "#{time_low}-#{time_mid}-#{time_hi}-#{clock_seq}-#{node}"

Server

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