An implementation of the Reactor design pattern for multiplexed asynchronous single-thread IO.
This module is a pure-Ruby implementation of an asynchronous multiplexed IO Reactor which is based on the Reactor design pattern found in Pattern-Oriented Software Architecture, Volume 2: Patterns for Concurrent and Networked Objects. It allows a single thread to demultiplex and dispatch events from one or more IO objects to the appropriate handler.
This is a very trivial example -- in most circumstances you'd only use a Reactor when you're trying to manage reading and writing on more than a single IO object.
require 'io/reactor'
reactor = IO::Reactor.new
data_to_send = "some stuff to send"
reader, writer = IO.pipe
# Read from the reader end of the pipe until the writer finishes
reactor.register( reader, :read ) do |io,event|
if io.eof?
reactor.unregister( io )
io.close
else
puts io.read( 256 )
end
end
# Write to the writer end of the pipe until there's no data left
reactor.register( writer, :write ) do |io,event|
bytes = io.write( data_to_send )
data_to_send.slice!( 0, bytes )
if data_to_send.empty?
reactor.unregister( io )
io.close
end
end
# Now pump the reactor until both sides are done
puts "Starting IO"
reactor.poll until reactor.empty?
puts "done, exiting."
See the examples/ directory for some working, more full-featured examples.
gem install io-reactor
You can check out the current development source with Mercurial like so:
hg clone http://repo.deveiate.org/IO-Reactor
Or if you prefer Git, via its Github mirror:
https://github.com/ged/io-reactor
After checking out the source, run:
$ rake newb
This task will install any missing dependencies, run the tests/specs, and generate the API documentation.
Copyright (c) 2002-2011, Michael Granger All rights reserved.
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