update comments

[erebus.git] / modules / sockets.py

# Erebus IRC bot - Author: Erebus Team
# vim: fileencoding=utf-8
# Configurable sockets module. DO NOT USE without understanding the risks
# This file is released into the public domain; see http://unlicense.org/

# Note: this module doesn't do any kind of authentication, so anyone who can connect to the bound port can spam you.

"""
To use - add in bot.config something like:

[sockets]
127.0.0.1:1337 = #example

The left side is the address to listen on and the right side is the channel to send to.
The exmaple will send incoming lines/packets on localhost, port 1337 to channel #example

The full syntax for the address is:
[unix:]</path/to/socket>
[udp|tcp:][<ip>:]<port>


Address examples:

Unix domain socket:          /path
Unix domain socket:          unix:/path
TCP socket (all interfaces): 1337
TCP socket (one interface):  127.0.0.1:1337
UDP socket (all interfaces): udp:1337
UDP socket (one interface):  udp:127.0.0.1:1337
"""

# module info
modinfo = {
	'author': 'Erebus Team',
	'license': 'public domain',
	'compatible': [0],
	'depends': [],
	'softdeps': [],
}

# preamble
import modlib
lib = modlib.modlib(__name__)
def modstart(parent, *args, **kwargs):
	gotParent(parent)
	return lib.modstart(parent, *args, **kwargs)
modstop = lib.modstop

# module code

def gotParent(parent):
	for bindto, channel in parent.cfg.items('sockets'):
		@lib.bind(bindto, data=channel)
		class BasicServer(object):
			def __init__(self, sock, data):
				# NB neither directly referencing `channel`, nor trying to pass it through a default-arg-to-a-lambda like the python docs suggest, works here.
				# Yay python. At least passing it via bind works.
				self.chan = data
				self.buffer = b''
				self.sock = sock

			def getdata(self):
				recvd = self.sock.recv(8192)
				if recvd == b"": # EOF
					if len(self.buffer) != 0:
						# Process what's left in the buffer. We'll get called again after.
						remaining_buf = self.buffer.decode('utf-8', 'backslashreplace')
						self.buffer = b""
						return [remaining_buf]
					else:
						# Nothing left in the buffer. Return None to signal the core to close this socket.
						return None
				self.buffer += recvd
				lines = []

				while b"\n" in self.buffer:
					pieces = self.buffer.split(b"\n", 1)
					s = pieces[0].decode('utf-8', 'backslashreplace').rstrip("\r")
					lines.append(pieces[0].decode('utf-8', 'backslashreplace'))
					self.buffer = pieces[1]

				return lines

			def parse(self, line):
				try:
					bot = lib.parent.channel(self.chan).bot
				except AttributeError: # <class 'AttributeError'> 'NoneType' object has no attribute 'bot'
					bot = lib.parent.randbot()
				maxlen = bot.maxmsglen() - len("PRIVMSG  :") - len(self.chan)
				while len(line) > maxlen:
					cutat = line.rfind(' ', 0, maxlen)
					if cutat == -1:
						cutat = maxlen
					bot.msg(self.chan, line[0:cutat])
					line = line[cutat:].strip()
				bot.msg(self.chan, line)

			def send(self, line):
				if lib.parent.parent.cfg.getboolean('debug', 'io'):
					lib.parent.log(str(self), 'O', line)
				self.sock.sendall(line.encode('utf-8', 'backslashreplace')+b"\r\n")

			def _getsockerr(self):
				try: # SO_ERROR might not exist on all platforms
					return self.socket.getsockopt(socket.SOL_SOCKET, socket.SO_ERROR)
				except:
					return None

			def __str__(self):
				return '%s#%d' % (__name__, self.sock.fileno())
			def __repr__(self):
				return '<%s #%d %s:%d>' % ((__name__, self.sock.fileno())+self.sock.getpeername())