IRC Single Message Bot. Sends a single IRC message to a channel, then quits. Useful for job notifications maybe

__init__.py

from irc.bot import ServerSpec
import irc
import sys
import json

try:
    with open('smbotconfig.json') as f:
        conf = json.load(f)
except:
    print "Error in config or no config found, returning to defaults. Please edit smbotconfig.json (http://jsonlint.com/) and restart the bot"
    with open('smbotconfig.json', 'w') as f:
        f.write(json.dumps(dict(channel="#blha303",
                            nickname="SingleMessageTest",
                            server="irc.esper.net") ) )
    sys.exit(1)

class SingleMessageClient(object):
    reactor_class = irc.client.Reactor

    def __init__(self):
        self.reactor = self.reactor_class()
        self.connection = self.reactor.server()
        self.dcc_connections = []
        self.reactor.add_global_handler("all_events", self._dispatcher, -10)
        self.reactor.add_global_handler("dcc_disconnect",
            self._dcc_disconnect, -10)

    def _dispatcher(self, connection, event):
        """
        Dispatch events to on_<event.type> method, if present.
        """
        do_nothing = lambda c, e: None
        method = getattr(self, "on_" + event.type, do_nothing)
        method(connection, event)

    def _dcc_disconnect(self, c, e):
        self.dcc_connections.remove(c)

    def connect(self, *args, **kwargs):
        """Connect using the underlying connection"""
        self.connection.connect(*args, **kwargs)

    def dcc_connect(self, address, port, dcctype="chat"):
        """Connect to a DCC peer.

        Arguments:

            address -- IP address of the peer.

            port -- Port to connect to.

        Returns a DCCConnection instance.
        """
        dcc = self.reactor.dcc(dcctype)
        self.dcc_connections.append(dcc)
        dcc.connect(address, port)
        return dcc

    def dcc_listen(self, dcctype="chat"):
        """Listen for connections from a DCC peer.

        Returns a DCCConnection instance.
        """
        dcc = self.reactor.dcc(dcctype)
        self.dcc_connections.append(dcc)
        dcc.listen()
        return dcc

    def start(self):
        """Start the IRC client."""
        while 1:
            if not self.connection.is_connected():
                break
            self.reactor.process_once(0.2)

class SingleMessageBot(SingleMessageClient):
    def __init__(self, msg, channel=conf.get('channel'),
                            nickname=conf.get('nickname'),
                            realname=conf.get('realname', conf.get('nickname', None)),
                            server=conf.get('server'),
                            port=conf.get('port', 6667),
                            password=conf.get('password', None),
                            **connect_params):
        super(SingleMessageBot, self).__init__()
        self.__connect_params = connect_params
        self.channel = channel
        self.server = ServerSpec(server, port, password)
        self.msg = msg
        self._nickname = nickname
        self._realname = realname
        for i in ["join", "kick", "mode",
                  "namreply", "nick", "part", "quit"]:
            self.connection.add_global_handler(i, getattr(self, "_on_" + i),
                -20)

    def _connect(self):
        """
        Establish a connection to the server at the front of the server_list.
        """
        try:
            self.connect(self.server.host, self.server.port, self._nickname,
                self.server.password, ircname=self._realname,
                **self.__connect_params)
        except irc.client.ServerConnectionError:
            pass

    def _on_join(self, c, e):
        ch = e.target
        nick = e.source.nick
        if nick == c.get_nickname():
            self.channels[ch] = Channel()
        self.channels[ch].add_user(nick)

    def _on_kick(self, c, e):
        nick = e.arguments[0]
        channel = e.target

        if nick == c.get_nickname():
            del self.channels[channel]
        else:
            self.channels[channel].remove_user(nick)

    def _on_mode(self, c, e):
        modes = irc.modes.parse_channel_modes(" ".join(e.arguments))
        t = e.target
        if irc.client.is_channel(t):
            ch = self.channels[t]
            for mode in modes:
                if mode[0] == "+":
                    f = ch.set_mode
                else:
                    f = ch.clear_mode
                f(mode[1], mode[2])
        else:
            # Mode on self... XXX
            pass

    def _on_namreply(self, c, e):
        """
        e.arguments[0] == "@" for secret channels,
                          "*" for private channels,
                          "=" for others (public channels)
        e.arguments[1] == channel
        e.arguments[2] == nick list
        """

        ch_type, channel, nick_list = e.arguments

        if channel == '*':
            # User is not in any visible channel
            # http://tools.ietf.org/html/rfc2812#section-3.2.5
            return

        for nick in nick_list.split():
            nick_modes = []

            if nick[0] in self.connection.features.prefix:
                nick_modes.append(self.connection.features.prefix[nick[0]])
                nick = nick[1:]

            for mode in nick_modes:
                self.channels[channel].set_mode(mode, nick)

            self.channels[channel].add_user(nick)

    def _on_nick(self, c, e):
        before = e.source.nick
        after = e.target
        for ch in self.channels.values():
            if ch.has_user(before):
                ch.change_nick(before, after)

    def _on_part(self, c, e):
        nick = e.source.nick
        channel = e.target

        if nick == c.get_nickname():
            del self.channels[channel]
        else:
            self.channels[channel].remove_user(nick)

    def _on_quit(self, c, e):
        nick = e.source.nick
        for ch in self.channels.values():
            if ch.has_user(nick):
                ch.remove_user(nick)

    def die(self, msg="Bye, cruel world!"):
        self.connection.disconnect(msg)

    def get_version(self):
        """Returns the bot version.

        Used when answering a CTCP VERSION request.
        """
        return "Python irc.bot ({version})".format(
            version=irc.client.VERSION_STRING)

    def jump_server(self, msg="Changing servers"):
        """Connect to a new server, possibly disconnecting from the current.

        The bot will skip to next server in the server_list each time
        jump_server is called.
        """
        if self.connection.is_connected():
            self.connection.disconnect(msg)

        self.server_list.append(self.server_list.pop(0))
        self._connect()

    def on_ctcp(self, c, e):
        """Default handler for ctcp events.

        Replies to VERSION and PING requests and relays DCC requests
        to the on_dccchat method.
        """
        nick = e.source.nick
        if e.arguments[0] == "VERSION":
            c.ctcp_reply(nick, "VERSION " + self.get_version())
        elif e.arguments[0] == "PING":
            if len(e.arguments) > 1:
                c.ctcp_reply(nick, "PING " + e.arguments[1])
        elif e.arguments[0] == "DCC" and e.arguments[1].split(" ", 1)[0] == "CHAT":
            self.on_dccchat(c, e)

    def on_dccchat(self, c, e):
        pass

    def start(self):
        """Start the bot."""
        self._connect()
        super(SingleMessageBot, self).start()

    def on_welcome(self, c, e):
        c.join(self.channel)
        c.privmsg(self.channel, self.msg)
        c.close()

def main(msg):
    b = SingleMessageBot(msg)
    b.start()
    return 0

if __name__ == "__main__":
    sys.exit(main(" ".join(sys.argv[1:]) if len(sys.argv) > 1 else "This is a test of SingleMessageBot!"))