initial message passing structure for runner

TODO

@@ -0,0 +1,54 @@
+# runners = []
+# cores.each do |c|
+#   in = pipes[c][0]
+#   out = pipes[c][1]
+#   runners << TestRunner.new(in, out)
+# end
+#
+# files = [ ... ]
+# results = []
+#
+# runners.each do |r|
+#   Thread.new do
+#     while !files.empty?
+#       results << r.run_file(files.pop)
+#     end
+#     r.shutdown
+#   end
+# end
+#
+# puts results.join("\n")
+#
+
+
+# Master
+# boot up workers
+# listen for worker messages
+# add worker messages to message queue
+# process message queue
+# "reply" to a message allows sending a message back down to worker
+#
+# When worker asks for file but no files left, send shutdown message to worker
+# when worker connection breaks, end thread
+# wait on all threads
+# when all threads are done, all workers must be done
+#
+#
+# Worker
+# boot up runners
+# listen for runner messages
+# add runner messages to message queue
+# process message queue
+# "reply" to a message allows sending message back down to runner
+#
+# when a runner asks for file but master responds with shutdown, mark self
+#   as terminated, shut down runners. Any runner that asks for a file is
+#   auto-terminated
+# wait for runner threads to finish
+# then exit, breaking master connection
+#
+# Runner
+# when booted, ask for a file
+# then process messages on the queue
+# when it's a file, run it and send a results message
+# when it's a shutdown, break main loop

lib/hydra.rb

@@ -1,2 +1,5 @@
 require 'hydra/pipe'
 require 'hydra/ssh'
+require 'hydra/message'
+require 'hydra/runner'
+

lib/hydra/message.rb

@@ -0,0 +1,8 @@
+module Hydra #:nodoc:
+  class Message #:nodoc:
+    def self.build(str)
+      eval(str).new
+    end
+  end
+end
+require 'hydra/message/runner_requests_file'

lib/hydra/message/runner_requests_file.rb

@@ -0,0 +1,9 @@
+module Hydra #:nodoc:
+  module Messages #:nodoc:
+    class RunnerRequestsFile < Hydra::Message
+      def serialize
+        "Hydra::Messages::RunnerRequestsFile"
+      end
+    end
+  end
+end

lib/hydra/runner.rb

@@ -0,0 +1,8 @@
+module Hydra #:nodoc:
+  class Runner
+    def initialize(io)
+      @io = io
+      @io.write Hydra::Messages::RunnerRequestsFile.new.serialize
+    end
+  end
+end

test/test_runner.rb

@@ -0,0 +1,20 @@
+require File.join(File.dirname(__FILE__), 'helper')
+
+class TestRunner < Test::Unit::TestCase
+  context "a test runner" do
+    setup do
+      @pipe = Hydra::Pipe.new
+      Process.fork do
+        @pipe.identify_as_child
+        Hydra::Runner.new(@pipe)
+      end
+      @pipe.identify_as_parent
+    end
+    should "request a file on boot" do
+      @message = Hydra::Message.build(@pipe.gets)
+      assert @message.is_a?(Hydra::Messages::RunnerRequestsFile)
+    end
+    should "return a result message after processing a file"
+    should "terminate when sent a shutdown message"
+  end
+end