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This manual documents A2K, an IRC bot.

Copyright © 2000, 2001 Mark Cornick and contributors. Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.1 or any later version published by the Free Software Foundation; with the Invariant Section being "Commentary", no Front-Cover Texts and one Back-Cover Text: "WARNING: The Surgeon General has determined that taking IRC too seriously is dangerous to your health." A copy of the license is included in the section entitled "GNU Free Documentation License".

A2K is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but without any warranty; without even the implied warranty of merchantability or fitness for a particular purpose. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA

A Transparent copy of this manual (as defined by the GNU Free Documentation License) is included in the A2K distribution, available from the A2K web site. PythonPowered.png


Node:Introduction, Next:, Previous:Top, Up:Top

Introduction

A2K is a small, simple, and unobtrusive IRC bot. It differs from the other n+1 IRC bots out there in that it is meant to do only a few things, do them well, and generally be seen and not heard. A2K offers the following features:

Why the name A2K? Originally this was called Accutron 2000; however, Accutron is a brand of watches manufactured by Bulova, and the name was changed to avoid confusion with their trademark. A2K is not an acronym; it does not stand for anything.

WARNING: The Surgeon General has determined that taking IRC too seriously is dangerous to your health.


Node:Installation, Next:, Previous:Introduction, Up:Top

Installation

A2K is written in Python. It has been tested on Solaris (2.6/7/8), Red Hat Linux (6.2/7.0) and Microsoft Windows (98) with Python versions 1.5.2, 1.6 and 2.0.

A2K is free software, distributed under the terms of the GNU General Public License from the A2K web site.

A2K requires no unusual installation procedure; simply extract the distribution archive into a directory. It is recommended that you keep all of the distributed files in the same directory. You should have the following files:


Node:Configuration, Next:, Previous:Installation, Up:Top

Configuring And Starting A2K

You will need to configure A2K before running it for the first time. All options are set in the a2kconf.py file. A2K will refuse to run if certain options are not configured. You must change these from their default values.

The Configuration Module

The a2kconf.py file contains all of A2K's configurable options. You should set each one of these options to define the identity, home, and other features of A2K. Be careful when editing a2kconf.py to maintain the syntax in the file.

These are the options configured in a2kconf.py:

server: This is a list of hostnames and ports of IRC servers that A2K should connect to. On startup, it will connect to the first hostname and port in the list. In order for the jump command to be useful, there should be at least two hostname/port tuples in this list.

nick: This is the nickname that A2K should use. The IRC protocol says it should be nine characters or less, but many IRC servers permit longer nicknames.

name: This is the "real name" A2K should use. For instance, if nick is "jdoe", name might be "John Doe".

channel: This is the IRC channel that A2K should join. IRC channels usually start with the "#" character.

chanmodes: This is a set of IRC channel modes that A2K should set when joining channel, if it can. For instance, "+nt-i" would result in A2K setting the "n" and "t" modes, and clearing the "i" mode.

botsnacks: This specifies whether A2K should eat botsnacks. Set to 0 to disable, or 1 to enable. When enabled, A2K will smile whenever the word "botsnack" is said on the IRC channel.

password: This is a password that will be required when sending commands to A2K. This password will be sent in clear text via the IRC server, so it should not be a password you use for anything valuable.

urllist: This is a filename where A2K will write URLs that appear on the IRC channel. The format of this file is standard HTML. If it does not exist when A2K starts running, it will be created.

opdelay: This specifies the number of seconds that A2K will wait before giving ops to someone joining the channel. It is recommended that you not set this to 0. The default is 5.

The Op List

The a2kconf.py file also contains the list of channel operators. A2K will give channel operator status to users who match the criteria specified in this file. You should list all of the users who are to receive channel operator privileges.

A2K uses regular expressions to specify the username and hostname patterns that correspond to valid channel operators. If you are unfamiliar with regular expressions, please consult a reference such as Mastering Regular Expressions by Jeffrey E.E. Friedl, published by O'Reilly And Associates.

The channel operator list is kept in a Python data structure called a "dictionary". Each item in a dictionary has a key and a definition. In our case, the key is an IRC nickname, and the definition is a regular expression which the nickname's user and host must match. For instance, suppose there is a user named Bullwinkle J. Moose at Wassamatta U. He uses the nickname "bullwinkle" and should get channel operator privileges when connecting from machines in the "wassamatta.edu" domain, where his login is "moose". In the operator list, his key would be "bullwinkle" and a good definition would be "moose@.*\.wassamatta\.edu".

a2kconf.py contains several lines of the form

op['key'] = re.compile('definition')

where key and definition are as specified above. To continue the Bullwinkle example, his entry in a2kconf.py would look like this:

op['bullwinkle'] = re.compile('moose@.*\.wassamatta\.edu')

And his friend Rocket J. Squirrel, whose login at Wassamatta is "squirrel" and whose nickname is "rocky", might have an entry like:

op['rocky'] = re.compile('squirrel@.*\.wassamatta\.edu')

However, consider the case of Natasha Fatale, nickname "natasha", who is not only attending Wassamatta U., where her login is "fatale", but uses AOL as well, where her screen name is also "fatale". Her entry might look like:

op['natasha'] = re.compile('fatale@(.*\.wassamatta\.edu|.*\.aol\.com)')

As you can see, using regular expressions for the patterns to be matched allows a fair amount of flexibility and complexity.

You should have one line similar to the above in a2kconf.py for each individual user who is to receive channel operator privileges.

Starting A2K

After editing the a2kconf.py file, A2K is ready to run. To start A2K, instruct your Python interpreter to run a2k.py. On UNIX systems, you can run a2k.py directly if the Python interpreter is in your path. On Microsoft Windows systems, you can double-click the a2k icon.

A2K normally produces no output. You will know that A2K is running when you see it join the channel you specified, using the nickname you specified.


Node:Commands, Next:, Previous:Configuration, Up:Top

A2K Commands

If you are listed in A2K's op list, you can send commands to A2K to alter its behavior while it is running. To do this, you send a private message to the bot's nickname. The message should be in the following format: password command arguments, where password is the password specified in a2kconf.py, command is a command from the following list, and arguments is one or more arguments required by the command. (Some commands take no arguments; you would omit arguments in this case.)

These are the commands currently understood by A2K:

die: Causes A2K to stop running. The bot will disconnect from the IRC server.

addop nickname regexp: Adds an entry to the channel operator list for the nickname specified. regexp should be a regular expression in the same format used in a2kconf.py. If there is already an entry for nickname, it is replaced by the new one.

delop nickname: Deletes the entry for nickname from the channel operator list, if such an entry exists. If no such entry exists, you will be notified.

showop nickname: Shows you the entry for nickname from the channel operator list, if such an entry exists. If no such entry exists, you will be notified.

jump: Causes A2K to disconnect from its current server and connect to the next server in its list. If you have only one server defined, this command disconnects and then immediately reconnects to the same server. This is useless, but benign.

nick nickname: Changes A2K's nickname to nickname.

passwd password: Changes the password used to authenticate these commands to password.

writeconf: Writes the current configuration to a2kconf.py. Do this to make changes made via addop, delop, nick, server and/or passwd permanent.

botsnacks: Turn botsnack consumption on. A2K will smile when "botsnack" is heard on the IRC channel.

nobotsnacks: Turn botsnack consumption off. A2K will not smile when "botsnack" is heard on the IRC channel.

cycleurls backupname: Renames the urllist file to backupname, and starts a new urllist file. Useful when the urllist file starts getting a little long.

inviteme: Requests an invitation to the channel. If the person requesting the invite is on the op list, A2K will issue the invite itself; otherwise, it will send a notice to the channel saying that an invite has been requested (and someone else will have to do the actual inviting.) This is, obviously, useful iff mode +i is set on the channel. Note: This command does not require a password; do not specify one. The entire contents of the message to A2K should be "inviteme".


Node:URL Catcher, Next:, Previous:Commands, Up:Top

The URL Catcher

The URL catcher records URLs that A2K sees on its IRC channel in a file. This file can be placed anywhere on your system; use the urllist option in a2kconf.py to specify its location. Any given URL will be recorded only once. Also, all URLs are checked for validity before being recorded. URLs requiring authentication (username and password) are not recorded. Finally, only URLs beginning in http://, https:// ftp:// and gopher:// are recorded. If a URL does not seem to be caught by A2K, bear these conditions in mind.

Note that URLs beginning in https:// are only recorded if your Python interpreter was configured to support the HTTPS protocol. This is not always the case, depending on your platform and Python version. Python 1.5.2 as shipped with Red Hat Linux 7 works with HTTPS, and could perhaps be used as an example case if you are building Python to support this feature.


Node:Commentary, Next:, Previous:URL Catcher, Up:Top

Commentary

Bad attitude ahead! Do not read this chapter if you are easily annoyed or offended.

Some may wonder why A2K was written when there are many other IRC bots available. I frequent a channel which I won't name here (it's private) except as The Channel Which Must Not Be Named. On TCWMNBN, we needed a bot that would handle just a few things without excessive 3l33t s+uph or other kitchen-sink capabilities. Because our hubris was strong, we decided to write our own. Our first attempt at this was called "foetus", and worked pretty well but grew into a monstrously unmaintainable Perl script. Later, I ripped out almost all of foetus and created a smaller, leaner version called "reify" which was meant to do just a few things but do them well. After reify fell into disrepair, I started writing A2K from scratch. I could have fixed reify instead, but I've been away from it for a long, long time. In the meantime, it seemed to have stopped working with the latest Net::IRC modules, and I'm not sure if that's reify's fault or Net::IRC's fault (Net::IRC always was a little buggy in spots.) Plus, I wanted to do a project that would teach me about raw socket I/O. And I wanted to do it in Python. So there. :)

OK, so there are n+1 other IRC bots available already. It was the vogue project for a while (until people started writing lots of ICQ clients and MP3 rippers...) You've got Eggdrop which does just about anything, you've got Infobot which gathers information, and you've got 31337 w4r b0tZ for the antisocial IRC crowd. A2K is none of the above: it is a simple, useful bot which doesn't pretend to do a lot of things that really aren't necessary for what I need in a bot. It only does a few things, and tries to do them well. Does it succeed? So far, yeah, more or less. Of course, that's just my opinion. If A2K isn't up to snuff for whatever you use bots for, feel free to not use it. But I have a feeling I'm not the only one with these requirements.

A2K's feature set corresponds to the somewhat limited requirements I have for it. If it doesn't do X, Y or Z that you want it to, well, this is a GPL licensed program, feel free to hack it around until it meets your requirements. You can send me patches but I may or may not include them - it depends on whether I personally feel they improve the program. For instance, code that improves A2K's ability to deal with net splits has a better chance of getting in than code that implements XDCC warez sharing with integrated leech ping-flooding. Of course, if X Y or Z is something that I wanted it to do, and it doesn't, that's probably a bug, and I want to hear about it.

On TCWMNBN, there are only two types of users: those with ops, and those without (and those without are rare, as TCWMNBN is private and we don't get a lot of visitors.) So I have no need to create multiple levels of eliteness, as in other bots such as Eggdrop. If you want the functionality of Eggdrop, use Eggdrop.

A2K may not work on all IRC networks. If you can provide me with a patch that makes it work on a given IRC network, I'll probably include it, but I only test A2K on one network (The Network Which Must Not Be Named, which uses ircd-hybrid) and if it works there for me, it's all good as far as I'm concerned.

As you may know, many IRC operators and networks don't like bots. If they don't want bots on their servers, that's their prerogative. If you get yourself K-lined somewhere because you were running A2K against the rules of that server/net/whatever, well, tough titty, I don't want to hear about it. I will not add any code to make A2K appear to not be a bot; this is a decent, well-behaved bot, dammit, not an 3l33t w4r h4qr b0t.

I apologize if that last paragraph put you off. I just see too much stupidity on the net these days and I felt the need to make a preemptive strike or two. I hope you like A2K and that you find it useful; otherwise, I wouldn't be releasing it, now would I? All I ask is that you have a clue. Hopefully you've got a clue now. If not, let me know and I'll try harder. Really, I'm a nice guy, I just don't like dealing with stupidity.


Node:Acknowledgements, Next:, Previous:Commentary, Up:Top

Acknowledgments

Joel Rosdahl wrote irclib.py and ircbot.py. Jason Cooper wrote the first implementation of server switching (no longer in use) and kibitzes from time to time. Everything else is Mark Cornick's fault.


Node:Dedications, Next:, Previous:Acknowledgements, Up:Top

Dedications

A2K is dedicated to the men and women of The Channel Which Must Not Be Named, who benefit from my work yet chronically ignore it because it has nothing to do with the Dreamcast. I am nothing if not selfless.


Node:History, Next:, Previous:Dedications, Up:Top

History


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Concept Index


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Variable Index


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Command Index