Class: EventMachine::Channel

Overview

Provides a simple thread-safe way to transfer data between (typically) long running tasks in defer and event loop thread.

Examples:

channel = EventMachine::Channel.new
sid     = channel.subscribe { |msg| p [:got, msg] }

channel.push('hello world')
channel.unsubscribe(sid)

#<<(*items)

Alias for #push.
#num_subscribers

Return the number of current subscribers.
#pop(*a, &b)

Fetches one message from the channel.
#push(*items) (also: #<<)

Add items to the channel, which are pushed out to all subscribers.
#subscribe(*a, &b) ⇒ Integer

Takes any arguments suitable for EM::Callback() and returns a subscriber id for use when unsubscribing.
#unsubscribe(name)

Removes subscriber from the list.
#gen_id private Internal use only Internal use only

[ GitHub ]

# File 'lib/em/channel.rb', line 15


def initialize
  @subs = {}
  @uid  = 0
end

Alias for #push.

[ GitHub ]

# File 'lib/em/channel.rb', line 50


alias << push

This method is for internal use only.

[ GitHub ]

# File 'lib/em/channel.rb', line 65


def gen_id
  @uid += 1
end

Return the number of current subscribers.

[ GitHub ]

# File 'lib/em/channel.rb', line 21


def num_subscribers
  return @subs.size
end

Fetches one message from the channel.

[ GitHub ]

# File 'lib/em/channel.rb', line 53


def pop(*a, &b)
  EM.schedule {
    name = subscribe do |*args|
      unsubscribe(name)
      EM::Callback(*a, &b).call(*args)
    end
  }
end

Add items to the channel, which are pushed out to all subscribers.

[ GitHub ]

# File 'lib/em/channel.rb', line 46


def push(*items)
  items = items.dup
  EM.schedule { items.each { |i| @subs.values.each { |s| s.call i } } }
end

Removes subscriber from the list.

Parameters: