Go Channels in Ruby

Question

In the Go programming language, you can send Messages around using a construct called "Channels". http://golang.org/doc/effective_go.html#channels

I would love to use something like that in Ruby, especially for IPC.

Pseudocode of what I want:

channel = Channel.new

fork do
  3.times{ channel.send("foo ") }
  exit!
end

Thread.new do
  3.times{ channel.send("bar ") }
end

loop do
  print channel.recv
end

# ~> bar foo foo bar bar foo

Is there any construct, library or equivalent for Ruby which works like that ?

If not: What is the best way to build such an abstraction?

UPDATE: To clarify what I need from these Channels.

One use case: Some forked workers waiting for jobs. They all read from the same JobChannel and report results to the same ResultChannel.

The Channels I need

• are very fast,
• writes do not block, (message sending)
• reads do block, (message receiving)
• do not need special treatment before forking,
• lightweight and simple would be nice.

So far I played around with

• DRb, (opposite of lightweight + slow + too much magic for my little brain)
• Sockets, (UNIXSocket, TCPSocket ... Sockets seem to have many many ways of using them. I got a half-working channel on UNIXSockets. If you think sockets make sense, what subset of features should I look at?)
• Pipes. (Connecting more than 2 Processes seems to be non-trivial)

If any of those was already the perfect technology for my problem, please provide tutorials etc. which have more focused information on my requirements.

Answer 1

Hi, check out this question: shared-variable-among-ruby-processes

and also check out drb

Hope it helps a bit.

Answer 2

Go's idea of message passing via channels, as a first-class construct, really only makes sense in the presence of concurrency (goroutines, tasklets, whatever you'd care to call them). With cheap concurrency, blocking a tasklet or coroutine is no longer a problem, and blocking message passing starts to make a lot more sense.

If this were Python, I'd point you at Stackless; in Ruby, perhaps Revactor or NeverBlock fit the bill for you?