Software / code / prosody
File
plugins/mod_admin_telnet.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 |
| parent | 10859:8de0057b4279 |
| child | 12977:74b9e05af71e |
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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. -- -- luacheck: ignore 212/self module:set_global(); module:depends("admin_shell"); local console_listener = { default_port = 5582; default_mode = "*a"; interface = "127.0.0.1" }; local async = require "util.async"; local st = require "util.stanza"; local def_env = module:shared("admin_shell/env"); local default_env_mt = { __index = def_env }; local function printbanner(session) local option = module:get_option_string("console_banner", "full"); if option == "full" or option == "graphic" then session.print [[ ____ \ / _ | _ \ _ __ ___ ___ _-_ __| |_ _ | |_) | '__/ _ \/ __|/ _ \ / _` | | | | | __/| | | (_) \__ \ |_| | (_| | |_| | |_| |_| \___/|___/\___/ \__,_|\__, | A study in simplicity |___/ ]] end if option == "short" or option == "full" then session.print("Welcome to the Prosody administration console. For a list of commands, type: help"); session.print("You may find more help on using this console in our online documentation at "); session.print("https://prosody.im/doc/console\n"); end if option ~= "short" and option ~= "full" and option ~= "graphic" then session.print(option); end end console = {}; local runner_callbacks = {}; function runner_callbacks:ready() self.data.conn:resume(); end function runner_callbacks:waiting() self.data.conn:pause(); end function runner_callbacks:error(err) module:log("error", "Traceback[telnet]: %s", err); self.data.print("Fatal error while running command, it did not complete"); self.data.print("Error: "..tostring(err)); end function console:new_session(conn) local w = function(s) conn:write(s:gsub("\n", "\r\n")); end; local session = { conn = conn; send = function (t) if st.is_stanza(t) and (t.name == "repl-result" or t.name == "repl-output") then t = "| "..t:get_text().."\n"; end w(tostring(t)); end; print = function (...) local t = {}; for i=1,select("#", ...) do t[i] = tostring(select(i, ...)); end w("| "..table.concat(t, "\t").."\n"); end; serialize = tostring; disconnect = function () conn:close(); end; }; session.env = setmetatable({}, default_env_mt); session.thread = async.runner(function (line) console:process_line(session, line); session.send(string.char(0)); end, runner_callbacks, session); -- Load up environment with helper objects for name, t in pairs(def_env) do if type(t) == "table" then session.env[name] = setmetatable({ session = session }, { __index = t }); end end session.env.output:configure(); return session; end function console:process_line(session, line) line = line:gsub("\r?\n$", ""); if line == "bye" or line == "quit" or line == "exit" or line:byte() == 4 then session.print("See you!"); session:disconnect(); return; end return module:fire_event("admin/repl-input", { origin = session, stanza = st.stanza("repl-input"):text(line) }); end local sessions = {}; function module.save() return { sessions = sessions } end function module.restore(data) if data.sessions then for conn in pairs(data.sessions) do conn:setlistener(console_listener); local session = console:new_session(conn); sessions[conn] = session; end end end function console_listener.onconnect(conn) -- Handle new connection local session = console:new_session(conn); sessions[conn] = session; printbanner(session); session.send(string.char(0)); end function console_listener.onincoming(conn, data) local session = sessions[conn]; local partial = session.partial_data; if partial then data = partial..data; end for line in data:gmatch("[^\n]*[\n\004]") do if session.closed then return end session.thread:run(line); end session.partial_data = data:match("[^\n]+$"); end function console_listener.onreadtimeout(conn) local session = sessions[conn]; if session then session.send("\0"); return true; end end function console_listener.ondisconnect(conn, err) -- luacheck: ignore 212/err local session = sessions[conn]; if session then session.disconnect(); sessions[conn] = nil; end end function console_listener.ondetach(conn) sessions[conn] = nil; end module:provides("net", { name = "console"; listener = console_listener; default_port = 5582; private = true; });