Checking if a user is online

Cinch by itself tries to keep track of the online state of users. Whenever it sees someone speak, change their nick or be in a channel the bot is also in, it’ll set the user to being online. And when a user quits, gets killed or cannot be whoised/contacted, its state will be set to offline.

A problem with that information is that it can quickly become out of sync. Consider the following example:

The bot joins a channel, sees someone in the name list and thus marks him as online. The bot then leaves the channel and at some later point, the user disconnects. The bot won’t know that and still track the user as online.

If (near-)realtime information about this state is required, one can use Cinch::User#monitor to automatically monitor the state. #monitor uses either the MONITOR feature of modern IRCds or, if that’s not available, periodically runs WHOIS to update the information.

Whenever a user’s state changes, either the :online or the :offline event will be fired, as can be seen in the following example:

class SomePlugin
  include Cinch::Plugin

  listen_to :connect, method: :on_connect
  listen_to :online,  method: :on_online
  listen_to :offline, method: :on_offline

  def on_connect(m)
    User("my_master").monitor
  end

  def on_online(m, user)
    user.send "Hello master"
  end

  def on_offline(m, user)
    @bot.loggers.info "I miss my master :("
  end
end

Sending messages to users and channels beside m.user and m.channel

Cinch provides helper methods to get instances of Channel and User objects that you can work with:

User('user').send("Hello!")        # Sends a message to user 'user'
Channel('#channel').send("Hello!") # Sends a message to channel '#channel'