Rinda (Ruby programming language)

Rinda is a Ruby implementation of Linda_(coordination_language) distributed computing paradigm. Linda defines a set of atomic operations on shared, virtual, (global) associative memory, called a tuplespace. In essence, it is like a distributed blackboard system for decoupled processes. Processes may add tuples to the blackboard or read/remove from the blackboard tuples that match a certain pattern.

Rinda builds on Linda/tuplespaces paradigm by offering some interesting additions. In particular, the Rinda implementation uses the case comparison (===) operator to match tuples. This means that tuples May Be matched using regular expressions, the classes of their elements, and the element values.

DRb server that offers a shared tuplespace:

require 'rinda/tuplespace'

URI = "druby://localhost:67671"
DRb.start_service(URI, Rinda::TupleSpace.new)
DRb.thread.join

Computational agent that accepts messages containing an arithmetic operator and two numbers, computes the result and stores it in tuplespace:

require 'rinda/rinda'

URI = "druby://localhost:67671"
DRb.start_service
ts = Rinda::TupleSpaceProxy.new(DRbObject.new(nil, URI))
loop do
  ops, a, b = ts.take([ %r{^[-+/*]$}, Numeric, Numeric])
  ts.write(["result", a.send(ops, b)])
end

The client submits tuples to the tuplespace and consumes the result when it is ready:

require 'rinda/rinda'

URI = "druby://localhost:67671"
DRb.start_service
ts = Rinda::TupleSpaceProxy.new(DRbObject.new(nil, URI))
tuples = [[ "*", 2, 2 ], [ "+", 2, 5 ], [ "-", 9, 3 ]]
tuples.each do |t|
  ts.write(t)
  res = ts.take(["result", nil])
  puts "#{res[1]} = #{t[1]} #{t[0]} #{t[2]}"
end

External links

• Rinda library reference