How can I get notified when an async method has finished it's job (callback) when using Celluloid?
Sample code:
require 'celluloid/autostart'
class Test
include Celluloid
def initialize(aaa)
@aaa = aaa
end
def foo
sleep 20
@bbb = 'asdasd'
end
def bar
"aaa is: #{@aaa}, bbb is: #{@bbb}"
end
end
x = Test.new 111
x.async.foo
I would like to get notified as soon as the job inside foo is done.
I recommend using the Observer pattern. Celluloid supports this via Notifications. Take a look at the wiki for some information: https://github.com/celluloid/celluloid/wiki/Notifications
Here's a working code example:
require 'rubygems'
require 'celluloid/autostart'
class Test
include Celluloid
include Celluloid::Notifications
def initialize(aaa)
@aaa = aaa
end
def foo
sleep 2
@bbb = 'asdasd'
publish "done!", "Slept for 2 seconds and set @bbb = #{@bbb}"
end
def bar
"aaa is: #{@aaa}, bbb is: #{@bbb}"
end
end
class Observer
include Celluloid
include Celluloid::Notifications
def initialize
subscribe "done!", :on_completion
end
def on_completion(*args)
puts "finished, returned #{args.inspect}"
end
end
y = Observer.new
x = Test.new 111
x.async.foo
sleep 3
Right now I think the new Conditions feature is the preferred way to handle this.
The example from the Celluloid wiki page on Conditions is too large to paste here, but simply put you can create a Condition object that is signalled by the called method once it is done. The caller can simply wait until the condition is met.
