paulbsd-salt/states/haproxy/scripts/weight.lua

local sleep_secs=15

local args = table.pack(...)
if args[1] ~= nil then sleep_secs = args[1] end

function getmax(t)
  local tmpvalue = 100000
  local svname
  local value

  for k,v in pairs(t) do
    if v < tmpvalue then
      svname = k
      value = v
    end

    tmpvalue = v
  end

  return svname, value
end

function arrange_backends()
  local try = 0
  local lastconns = 0

  while true do
    if lastconns == core.get_info()["CumConns"] then
      try = try+1
    end

    for _, backend in pairs(core.backends) do
      local results = {}
      for n,server in pairs(backend.servers) do
        if server:get_stats()["check_status"] ~= nil
          and server:get_stats()["status"] == "UP"
          and server:get_stats()["bck"] == 0 then
          if string.find(server:get_stats()["check_status"],"OK") ~= nil then
            local svname = server:get_stats()["svname"]
            local latency = server:get_stats()["check_duration"]
            results[svname] = latency
          end
        end
      end

      local b,c = getmax(results)
      if b ~= nil then
        for n,server in pairs(backend.servers) do
          if b == server.name then
            server:set_weight("10")
          else
            server:set_weight("1")
          end
        end
      end
    end

    lastconns = core.get_info()["CumConns"]

    if try == 10 then
      local msg = string.format("Worker with pid %s exited for arrange_backends task", core.get_info()["Pid"])
      print(msg)
      core.done(msg)
    end

    core.sleep(sleep_secs)
  end
end

core.register_task(arrange_backends)