ingress-nginx-helm/rootfs/etc/nginx/lua/monitor.lua
2020-06-10 17:36:56 +08:00

95 lines
2.4 KiB
Lua

local ngx = ngx
local tonumber = tonumber
local assert = assert
local string = string
local tostring = tostring
local socket = ngx.socket.tcp
local cjson = require("cjson.safe")
local new_tab = require "table.new"
local clear_tab = require "table.clear"
local clone_tab = require "table.clone"
-- if an Nginx worker processes more than (MAX_BATCH_SIZE/FLUSH_INTERVAL) RPS
-- then it will start dropping metrics
local MAX_BATCH_SIZE = 10000
local FLUSH_INTERVAL = 1 -- second
local metrics_batch = new_tab(MAX_BATCH_SIZE, 0)
local metrics_count = 0
local _M = {}
local function send(payload)
local s = assert(socket())
assert(s:connect("unix:/tmp/prometheus-nginx.socket"))
assert(s:send(payload))
assert(s:close())
end
local function metrics()
return {
host = ngx.var.host or "-",
namespace = ngx.var.namespace or "-",
ingress = ngx.var.ingress_name or "-",
service = ngx.var.service_name or "-",
path = ngx.var.location_path or "-",
method = ngx.var.request_method or "-",
status = ngx.var.status or "-",
requestLength = tonumber(ngx.var.request_length) or -1,
requestTime = tonumber(ngx.var.request_time) or -1,
responseLength = tonumber(ngx.var.bytes_sent) or -1,
upstreamLatency = tonumber(ngx.var.upstream_connect_time) or -1,
upstreamResponseTime = tonumber(ngx.var.upstream_response_time) or -1,
upstreamResponseLength = tonumber(ngx.var.upstream_response_length) or -1,
--upstreamStatus = ngx.var.upstream_status or "-",
}
end
local function flush(premature)
if premature then
return
end
if metrics_count == 0 then
return
end
local current_metrics_batch = clone_tab(metrics_batch)
clear_tab(metrics_batch)
metrics_count = 0
local payload, err = cjson.encode(current_metrics_batch)
if not payload then
ngx.log(ngx.ERR, "error while encoding metrics: ", err)
return
end
send(payload)
end
function _M.init_worker()
local _, err = ngx.timer.every(FLUSH_INTERVAL, flush)
if err then
ngx.log(ngx.ERR, string.format("error when setting up timer.every: %s", tostring(err)))
end
end
function _M.call()
if metrics_count >= MAX_BATCH_SIZE then
ngx.log(ngx.WARN, "omitting metrics for the request, current batch is full")
return
end
metrics_count = metrics_count + 1
metrics_batch[metrics_count] = metrics()
end
setmetatable(_M, {__index = {
flush = flush,
get_metrics_batch = function() return metrics_batch end,
}})
return _M