lsyncd/examples/lsayirc.lua
2022-11-11 15:27:21 +01:00

142 lines
4.0 KiB
Lua

-----
-- An Lsyncd+IRC-Bot Config
--
-- Logs into an IRC channel and tells there everything that happens in the
-- watched directory tree.
--
-- The challenge coding Lsyncd configs taking use of TCP sockets is
-- that they must not block! Otherwise Lsyncd will block, no longer
-- empty the kernels monitor queue, no longer collecting zombie processes,
-- no longer spawning processes (this example doesnt do any, but maybe you
-- might want to do that as well), blocking is just bad.
--
-- This demo codes just minimal IRC functionality.
-- it does not respond to anything else than IRC PING messages.
--
-- There is no flood control, if a lot happens the IRC server will disconnect
-- the bot.
--
-- Requires "luasocket" to be installed
require("socket")
-- For demo reasons, do not detach
settings.nodaemon = true
local hostname = "irc.freenode.org"
--hostname = "127.0.0.1"
local port = 6667
local nick = "lbot01"
local chan = "##lfile01"
-- this blocks until the connection is established
-- for once lets say this ok since Lsyncd didnt yet actually
-- start.
--- @diagnostic disable-next-line: undefined-global
local ircSocket, err = socket.connect(hostname, port)
if not ircSocket then
log("Error", "Cannot connect to IRC: ", err)
terminate(-1)
end
-- from now on, the socket must not block!
ircSocket:settimeout(0)
-- Buffers for stuff to send and receive on IRC:
local ircWBuf = ""
local ircRBuf = ""
-- Predeclaration for functions calling each other
local writeIRC
-----
-- Called when the IRC socket can be written again.
-- This happens when writeIRC (see below) couldnt write
-- its buffer in one go, call it again so it can continue its task.
local function ircWritey(fd)
writeIRC()
end
----
-- Called when there is data on the socket
local function ircReady(socket)
local l, err, ircRBuf = ircSocket:receive("*l", ircRBuf)
if not l then
if err ~= "timeout" then
log("Error", "IRC connection failed: ", err)
terminate(-1)
end
else
ircRBuf = ""
end
log("Normal", "ircin :", l)
--- answers ping messages
local ping = l:match("PING :(.*)")
if ping then
writeIRC("PONG :", ping, "\n")
end
end
-----
-- Writes on IRC socket
-- Do not forget to add an "/n".
function writeIRC(...)
-- Appends all arbuments into the write buffer
ircWBuf = ircWBuf..table.concat({...})
-- Gives it to the socket and sees how much it accepted
local s, err = ircSocket:send(ircWBuf)
-- If it cant the socket terminated.
if not s and err~="timeout" then
log("Error", "IRC connection failed: ", err)
terminate(-1)
end
--- logs what has been send, without the linefeed.
if (ircWBuf:sub(s, s) == "\n") then
log("Normal", "ircout:", ircWBuf:sub(1, s - 1))
else
log("Normal", "ircout: ", ircWBuf:sub(1, s), "\\")
end
---- reduces the buffer by the amount of data sent.
ircWBuf = ircWBuf:sub(s + 1, -1)
-- when the write buffer is empty tell the core to no longer
-- call ircWritey if data can be written on the socket. There
-- is nothing to be written. If there is data in the buffer
-- asks to be called as soon it can be written again
if ircWBuf == "" then
observefd(ircSocket:getfd(), ircReady, nil)
else
observefd(ircSocket:getfd(), ircReady, ircWritey)
end
end
-- Aquires the nick on IRC and joins the configured channel
-- This will also register the ircReady/ircWritey function at the core
-- to be called when the socket is ready to be read/written.
writeIRC("NICK ", nick, "\n")
writeIRC("USER ", nick, " 0 * :lsyncd-sayirc-bot", "\n")
writeIRC("JOIN ", chan, "\n")
-- As action tells on IRC what the action is, then instead of
-- spawning somthing, it discards the event.
local function action(inlet)
-- event2 is the target of a move event
local event, event2 = inlet.getEvent()
if not event2 then
writeIRC("PRIVMSG ",chan," :",event.etype," ",
event.path, "\n")
else
writeIRC("PRIVMSG ",chan," :",event.etype," ",
event.path," -> ",event2.path, "\n")
end
inlet.discardEvent(event)
end
-- Watch a directory, and use a second for delay to aggregate events a little.
sync{source = "src",
action = action,
delay = 1,
onMove = true}