--[[
  Release lock

    Input:
      KEYS[1] 'lock',
    
      ARGV[1]  token
      ARGV[2]  lock duration in milliseconds
      
    Output:
      "OK" if lock extended successfully.
]]
local rcall = redis.call

if rcall("GET", KEYS[1]) == ARGV[1] then
  return rcall("DEL", KEYS[1])
else
  return 0
end