view plugins/mod_http_files.lua @ 11523:5f15ab7c6ae5

Statistics: Rewrite statistics backends to use OpenMetrics The metric subsystem of Prosody has had some shortcomings from the perspective of the current state-of-the-art in metric observability. The OpenMetrics standard [0] is a formalization of the data model (and serialization format) of the well-known and widely-used Prometheus [1] software stack. The previous stats subsystem of Prosody did not map well to that format (see e.g. [2] and [3]); the key reason is that it was trying to do too much math on its own ([2]) while lacking first-class support for "families" of metrics ([3]) and structured metric metadata (despite the `extra` argument to metrics, there was no standard way of representing common things like "tags" or "labels"). Even though OpenMetrics has grown from the Prometheus world of monitoring, it maps well to other popular monitoring stacks such as: - InfluxDB (labels can be mapped to tags and fields as necessary) - Carbon/Graphite (labels can be attached to the metric name with dot-separation) - StatsD (see graphite when assuming that graphite is used as backend, which is the default) The util.statsd module has been ported to use the OpenMetrics model as a proof of concept. An implementation which exposes the util.statistics backend data as Prometheus metrics is ready for publishing in prosody-modules (most likely as mod_openmetrics_prometheus to avoid breaking existing 0.11 deployments). At the same time, the previous measure()-based API had one major advantage: It is really simple and easy to use without requiring lots of knowledge about OpenMetrics or similar concepts. For that reason as well as compatibility with existing code, it is preserved and may even be extended in the future. However, code relying on the `stats-updated` event as well as `get_stats` from `statsmanager` will break because the data model has changed completely; in case of `stats-updated`, the code will simply not run (as the event was renamed in order to avoid conflicts); the `get_stats` function has been removed completely (so it will cause a traceback when it is attempted to be used). Note that the measure_*_event methods have been removed from the module API. I was unable to find any uses or documentation and thus deemed they should not be ported. Re-implementation is possible when necessary. [0]: https://openmetrics.io/ [1]: https://prometheus.io/ [2]: #959 [3]: #960
author Jonas Schäfer <jonas@wielicki.name>
date Sun, 18 Apr 2021 11:47:41 +0200
parents a62b981db0e2
children 05c250fa335a
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-- Prosody IM
-- Copyright (C) 2008-2010 Matthew Wild
-- Copyright (C) 2008-2010 Waqas Hussain
--
-- This project is MIT/X11 licensed. Please see the
-- COPYING file in the source package for more information.
--

module:depends("http");

local open = io.open;
local fileserver = require"net.http.files";

local base_path = module:get_option_path("http_files_dir", module:get_option_path("http_path"));
local cache_size = module:get_option_number("http_files_cache_size", 128);
local cache_max_file_size = module:get_option_number("http_files_cache_max_file_size", 4096);
local dir_indices = module:get_option_array("http_index_files", { "index.html", "index.htm" });
local directory_index = module:get_option_boolean("http_dir_listing");

local mime_map = module:shared("/*/http_files/mime").types;
if not mime_map then
	mime_map = {
		html = "text/html", htm = "text/html",
		xml = "application/xml",
		txt = "text/plain",
		css = "text/css",
		js = "application/javascript",
		png = "image/png",
		gif = "image/gif",
		jpeg = "image/jpeg", jpg = "image/jpeg",
		svg = "image/svg+xml",
	};
	module:shared("/*/http_files/mime").types = mime_map;

	local mime_types, err = open(module:get_option_path("mime_types_file", "/etc/mime.types", "config"), "r");
	if not mime_types then
		module:log("debug", "Could not open MIME database: %s", err);
	else
		local mime_data = mime_types:read("*a");
		mime_types:close();
		setmetatable(mime_map, {
			__index = function(t, ext)
				local typ = mime_data:match("\n(%S+)[^\n]*%s"..(ext:lower()).."%s") or "application/octet-stream";
				t[ext] = typ;
				return typ;
			end
		});
	end
end

local function get_calling_module()
	local info = debug.getinfo(3, "S");
	if not info then return "An unknown module"; end
	return info.source:match"mod_[^/\\.]+" or info.short_src;
end

-- COMPAT -- TODO deprecate
function serve(opts)
	if type(opts) ~= "table" then -- assume path string
		opts = { path = opts };
	end
	if opts.directory_index == nil then
		opts.directory_index = directory_index;
	end
	if opts.mime_map == nil then
		opts.mime_map = mime_map;
	end
	if opts.cache_size == nil then
		opts.cache_size = cache_size;
	end
	if opts.cache_max_file_size == nil then
		opts.cache_max_file_size = cache_max_file_size;
	end
	if opts.index_files == nil then
		opts.index_files = dir_indices;
	end
	-- TODO Crank up to warning
	module:log("debug", "%s should be updated to use 'net.http.files' insead of mod_http_files", get_calling_module());
	return fileserver.serve(opts);
end

function wrap_route(routes)
	module:log("debug", "%s should be updated to use 'net.http.files' insead of mod_http_files", get_calling_module());
	for route,handler in pairs(routes) do
		if type(handler) ~= "function" then
			routes[route] = fileserver.serve(handler);
		end
	end
	return routes;
end

module:provides("http", {
	route = {
		["GET /*"] = fileserver.serve({
			path = base_path;
			directory_index = directory_index;
			mime_map = mime_map;
			cache_size = cache_size;
			cache_max_file_size = cache_max_file_size;
			index_files = dir_indices;
		});
	};
});