File

core/statsmanager.lua @ 12591:494577d883ff

util.table: Fix inaccurate comment Probably a duplicate of the comment next to Lmove, recorded by mistake Lpack can probably be removed at some point in the near future once we are confident it is not used anywhere.
author Kim Alvefur <zash@zash.se>
date Mon, 11 Jul 2022 20:02:10 +0200
parent 11575:76d32b2ca5eb
child 12972:ead41e25ebc0
line wrap: on
line source


local config = require "core.configmanager";
local log = require "util.logger".init("stats");
local timer = require "util.timer";
local fire_event = prosody.events.fire_event;
local array = require "util.array";
local timed = require "util.openmetrics".timed;

local stats_interval_config = config.get("*", "statistics_interval");
local stats_interval = tonumber(stats_interval_config);
if stats_interval_config and not stats_interval and stats_interval_config ~= "manual" then
	log("error", "Invalid 'statistics_interval' setting, statistics will be disabled");
end

local stats_provider_name;
local stats_provider_config = config.get("*", "statistics");
local stats_provider = stats_provider_config;

if not stats_provider and stats_interval then
	stats_provider = "internal";
elseif stats_provider and not stats_interval then
	stats_interval = 60;
end
if stats_interval_config == "manual" then
	stats_interval = nil;
end

local builtin_providers = {
	internal = "util.statistics";
	statsd = "util.statsd";
};


local stats, stats_err = false, nil;

if stats_provider then
	if stats_provider:sub(1,1) == ":" then
		stats_provider = stats_provider:sub(2);
		stats_provider_name = "external "..stats_provider;
	elseif stats_provider then
		stats_provider_name = "built-in "..stats_provider;
		stats_provider = builtin_providers[stats_provider];
		if not stats_provider then
			log("error", "Unrecognized statistics provider '%s', statistics will be disabled", stats_provider_config);
		end
	end

	local have_stats_provider, stats_lib = pcall(require, stats_provider);
	if not have_stats_provider then
		stats, stats_err = nil, stats_lib;
	else
		local stats_config = config.get("*", "statistics_config");
		stats, stats_err = stats_lib.new(stats_config);
		stats_provider_name = stats_lib._NAME or stats_provider_name;
	end
end

if stats == nil then
	log("error", "Error loading statistics provider '%s': %s", stats_provider, stats_err);
end

local measure, collect, metric, cork, uncork;

if stats then
	function metric(type_, name, unit, description, labels, extra)
		local registry = stats.metric_registry
		local f = assert(registry[type_], "unknown metric family type: "..type_);
		return f(registry, name, unit or "", description or "", labels, extra);
	end

	local function new_legacy_metric(stat_type, name, unit, description, fixed_label_key, fixed_label_value, extra)
		local label_keys = array()
		local conf = extra or {}
		if fixed_label_key then
			label_keys:push(fixed_label_key)
		end
		unit = unit or ""
		local mf = metric(stat_type, "prosody_" .. name, unit, description, label_keys, conf);
		if fixed_label_key then
			mf = mf:with_partial_label(fixed_label_value)
		end
		return mf:with_labels()
	end

	local function unwrap_legacy_extra(extra, type_, name, unit)
		local description = extra and extra.description or name.." "..type_
		unit = extra and extra.unit or unit
		return description, unit
	end

	-- These wrappers provide the pre-OpenMetrics interface of statsmanager
	-- and moduleapi (module:measure).
	local legacy_metric_wrappers = {
		amount = function(name, fixed_label_key, fixed_label_value, extra)
			local initial = 0
			if type(extra) == "number" then
				initial = extra
			else
				initial = extra and extra.initial or initial
			end
			local description, unit = unwrap_legacy_extra(extra, "amount", name)

			local m = new_legacy_metric("gauge", name, unit, description, fixed_label_key, fixed_label_value)
			m:set(initial or 0)
			return function(v)
				m:set(v)
			end
		end;

		counter = function(name, fixed_label_key, fixed_label_value, extra)
			if type(extra) == "number" then
				-- previous versions of the API allowed passing an initial
				-- value here; we do not allow that anymore, it is not a thing
				-- which makes sense with counters
				extra = nil
			end

			local description, unit = unwrap_legacy_extra(extra, "counter", name)

			local m = new_legacy_metric("counter", name, unit, description, fixed_label_key, fixed_label_value)
			m:set(0)
			return function(v)
				m:add(v)
			end
		end;

		rate = function(name, fixed_label_key, fixed_label_value, extra)
			if type(extra) == "number" then
				-- previous versions of the API allowed passing an initial
				-- value here; we do not allow that anymore, it is not a thing
				-- which makes sense with counters
				extra = nil
			end

			local description, unit = unwrap_legacy_extra(extra, "counter", name)

			local m = new_legacy_metric("counter", name, unit, description, fixed_label_key, fixed_label_value)
			m:set(0)
			return function()
				m:add(1)
			end
		end;

		times = function(name, fixed_label_key, fixed_label_value, extra)
			local conf = {}
			if extra and extra.buckets then
				conf.buckets = extra.buckets
			else
				conf.buckets = { 0.001, 0.01, 0.1, 1.0, 10.0, 100.0 }
			end
			local description, _ = unwrap_legacy_extra(extra, "times", name)

			local m = new_legacy_metric("histogram", name, "seconds", description, fixed_label_key, fixed_label_value, conf)
			return function()
				return timed(m)
			end
		end;

		sizes = function(name, fixed_label_key, fixed_label_value, extra)
			local conf = {}
			if extra and extra.buckets then
				conf.buckets = extra.buckets
			else
				conf.buckets = { 1024, 4096, 32768, 131072, 1048576, 4194304, 33554432, 134217728, 1073741824 }
			end
			local description, _ = unwrap_legacy_extra(extra, "sizes", name)

			local m = new_legacy_metric("histogram", name, "bytes", description, fixed_label_key, fixed_label_value, conf)
			return function(v)
				m:sample(v)
			end
		end;

		distribution = function(name, fixed_label_key, fixed_label_value, extra)
			if type(extra) == "string" then
				-- compat with previous API
				extra = { unit = extra }
			end
			local description, unit = unwrap_legacy_extra(extra, "distribution", name, "")
			local m = new_legacy_metric("summary", name, unit, description, fixed_label_key, fixed_label_value)
			return function(v)
				m:sample(v)
			end
		end;
	};

	-- Argument order switched here to support the legacy statsmanager.measure
	-- interface.
	function measure(stat_type, name, extra, fixed_label_key, fixed_label_value)
		local wrapper = assert(legacy_metric_wrappers[stat_type], "unknown legacy metric type "..stat_type)
		return wrapper(name, fixed_label_key, fixed_label_value, extra)
	end

	if stats.cork then
		function cork()
			return stats:cork()
		end

		function uncork()
			return stats:uncork()
		end
	else
		function cork() end
		function uncork() end
	end

	if stats_interval or stats_interval_config == "manual" then

		local mark_collection_start = measure("times", "stats.collection");
		local mark_processing_start = measure("times", "stats.processing");

		function collect()
			local mark_collection_done = mark_collection_start();
			fire_event("stats-update");
			-- ensure that the backend is uncorked, in case it got stuck at
			-- some point, to avoid infinite resource use
			uncork()
			mark_collection_done();
			local manual_result = nil

			if stats.metric_registry then
				-- only if supported by the backend, we fire the event which
				-- provides the current metric values
				local mark_processing_done = mark_processing_start();
				local metric_registry = stats.metric_registry;
				fire_event("openmetrics-updated", { metric_registry = metric_registry })
				mark_processing_done();
				manual_result = metric_registry;
			end

			return stats_interval, manual_result;
		end
		if stats_interval then
			log("debug", "Statistics enabled using %s provider, collecting every %d seconds", stats_provider_name, stats_interval);
			timer.add_task(stats_interval, collect);
			prosody.events.add_handler("server-started", function () collect() end, -1);
			prosody.events.add_handler("server-stopped", function () collect() end, -1);
		else
			log("debug", "Statistics enabled using %s provider, no scheduled collection", stats_provider_name);
		end
	else
		log("debug", "Statistics enabled using %s provider, collection is disabled", stats_provider_name);
	end
else
	log("debug", "Statistics disabled");
	function measure() return measure; end

	local dummy_mt = {}
	function dummy_mt.__newindex()
	end
	function dummy_mt:__index()
		return self
	end
	function dummy_mt:__call()
		return self
	end
	local dummy = {}
	setmetatable(dummy, dummy_mt)

	function metric() return dummy; end
	function cork() end
	function uncork() end
end

local exported_collect = nil;
if stats_interval_config == "manual" then
	exported_collect = collect;
end

return {
	collect = exported_collect;
	measure = measure;
	cork = cork;
	uncork = uncork;
	metric = metric;
	get_metric_registry = function ()
		return stats and stats.metric_registry or nil
	end;
};