gistfile1.txt

#!/opt/circonus/bin/luamtev -L+/opt/circonus/share/lua/5.1/?.lua;/opt/circonus/share/lua/5.1/?/init.lua

module(..., package.seeall)

function calc_next(last, period)
  if not last then last = mtev.timeval.now() end
  local ne = last:seconds() + period
  return mtev.timeval.new(math.floor(ne), math.floor((ne - math.floor(ne)) * 1000000))
end

function subs(a)
  if a == "{time}" then return math.floor(mtev.timeval.now():seconds()) end
  r = string.match(a, "{rand%((%d+)%)}")
  if r then
    return math.random(tonumber(r))
  end
  if a == "{rand}" then return math.random(100) end
  return a
end

function main()
  if arg[5] == nil then
    mtev.log("error", "%s <host> <port> <Hz> <template>\n\n", arg[1])
    mtev.log("error", "  template can include {time} and {rand} or {rand(X)}\n\n")
    mtev.log("error", "Example:\t%s 127.0.0.1 8125 2 \"agenttest.node.timetest.timing:{rand(400)}|ms|@0.05\"\n", arg[1])
    os.exit(-2)
  end
  local host = arg[2]
  local port = tonumber(arg[3])
  local period = 1 / tonumber(arg[4])
  local line = arg[5]

  mtev.log("stdout", "Sending every %f seconds to %s:%d\n", period, host, port)
  local e = mtev.socket('inet', 'udp')
  local last_attempt, next_attempt
  while true do
    last_attempt = next_attempt
    next_attempt = calc_next(last_attempt, period)

    local out = string.gsub(line, "(%b{})", subs)
    print(out)
    e:sendto(out, host, port)
    local sleep_time = (next_attempt - mtev.timeval.now()):seconds()
    if sleep_time < 0 then
      mtev.log("stdout", "can't send fast enough, falling behind %f seconds\n", sleep_time)
    else
      mtev.sleep(sleep_time)
    end
  end
end