Isaac - the smallish DSL for writing IRC bots

Features

Wraps parsing of incoming messages and raw IRC commands in simple constructs.
Hides all the ugly regular expressions of matching IRC commands. Leaves only the essentials for you to match.
Takes care of dull stuff such as replying to PING-messages and avoiding excess flood.

Getting started

An Isaac-bot needs a few basics:

require 'isaac'
configure do |c|
  c.nick    = "AwesomeBot"
  c.server  = "irc.freenode.net"
  c.port    = 6667
end

That’s it. Run ruby bot.rb and it will connect to the specified server.

Connecting

After the bot has connected to the IRC server you might want to join some channels:

on :connect do
  join "#awesome_channel", "#WesternBar"
end

Responding to messages

Joining a channel and sitting idle is not much fun. Let’s repeat everything being said in these channels:

on :channel do
  msg channel, message
end

Notice the channel and message variables. Additionally nick and match is available for channel-events. nick being the sender of the message, match being an array of captures from the regular expression:

on :channel, /^quote this: (.*)/ do
  msg channel, "Quote: '#{match[0]}' by #{nick}"
end

If you want to match private messages use the on :private event:

on :private, /^login (\S+) (\S+)/ do
  username = match[0]
  password = match[1]
  # do something to authorize or whatevz.
  msg nick, "Login successful!"
end

You can also pass the RegExp captures as block arguments:

on :channel, /catch this: (.*) and this: (.*)/ do |first, last|
  # `first` will contain the first regexp capture,
  # `last` the second.
end

Defining helpers

Helpers should not be defined in the top level, but instead using the helpers-constructor:

helpers do
  def rain_check(meeting)
    msg nick, "Can I have a rain check on the #{meeting}?"
  end
end

on :private, /date/ do
  rain_check("romantic date")
end

Errors, errors, errors

Errors, as specified by RFC 1459, can be reacted upon as well. If you e.g. try to send a message to a non-existant nick you will get error 401: “No such nick/channel”.

on :error, 401 do
  # Do something.
end

Available variables: nick and channel.

Non-top level bots

You might not want to pollute the top-level namespace with Isaac helpers, or you want to define multiple bots. This can be done easily, by requiring ‘isaac/bot` instead of `isaac`:

require 'isaac/bot'

bot = Isaac::Bot.new do
  configure do
    …
  end

  on :channel do
    …
  end
end

bot.start

Contribute

The source is hosted at GitHub: github.com/ichverstehe/isaac

License

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the “Software”), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.