Implemented the runners log functionality. It needs to handle the case when an invalid path is given

lib/hydra/master.rb

@@ -67,6 +67,7 @@ module Hydra #:nodoc:
 
       @string_runner_event_listeners = Array( opts.fetch( 'runner_listeners' ) { nil } )
 
+      @runner_log_file = opts.fetch('runner_log_file') { nil }
       @verbose = opts.fetch('verbose') { false }
       @autosort = opts.fetch('autosort') { true }
       @sync = opts.fetch('sync') { nil }
@@ -163,7 +164,7 @@ module Hydra #:nodoc:
       pipe = Hydra::Pipe.new
       child = SafeFork.fork do
         pipe.identify_as_child
-        Hydra::Worker.new(:io => pipe, :runners => runners, :verbose => @verbose, :runner_listeners => @string_runner_event_listeners )
+        Hydra::Worker.new(:io => pipe, :runners => runners, :verbose => @verbose, :runner_listeners => @string_runner_event_listeners, :runner_log_file => @runner_log_file )
       end
 
       pipe.identify_as_parent
@@ -175,7 +176,7 @@ module Hydra #:nodoc:
 
       runners = worker.fetch('runners') { raise "You must specify the number of runners"  }
       command = worker.fetch('command') {
-        "RAILS_ENV=#{@environment} ruby -e \"require 'rubygems'; require 'hydra'; Hydra::Worker.new(:io => Hydra::Stdio.new, :runners => #{runners}, :verbose => #{@verbose}, :runner_listeners => \'#{@string_runner_event_listeners}\' );\""
+        "RAILS_ENV=#{@environment} ruby -e \"require 'rubygems'; require 'hydra'; Hydra::Worker.new(:io => Hydra::Stdio.new, :runners => #{runners}, :verbose => #{@verbose}, :runner_listeners => \'#{@string_runner_event_listeners}\', :runner_log_file => \'#{@runner_log_file}\' );\""
       }
 
       trace "Booting SSH worker"

lib/hydra/runner.rb

@@ -16,7 +16,7 @@ module Hydra #:nodoc:
     # Boot up a runner. It takes an IO object (generally a pipe from its
     # parent) to send it messages on which files to execute.
     def initialize(opts = {})
-      redirect_output
+      redirect_output( opts.fetch( :runner_log_file ) { nil } )
       reg_trap_sighup
 
       @io = opts.fetch(:io) { raise "No IO Object" }
@@ -289,9 +289,8 @@ module Hydra #:nodoc:
       end.compact
     end
 
-    def redirect_output file_name = nil
-      file_name = 'log/hydra.log' if !file_name and File.exists? 'log/'
-      file_name = 'hydra.log' unless file_name
+    def redirect_output file_name
+      file_name = '/dev/null' unless file_name and !file_name.empty?
       $stderr = $stdout =  File.open(file_name, 'a')
     end
   end

lib/hydra/tasks.rb

@@ -41,6 +41,10 @@ module Hydra #:nodoc:
     # Set to false if you don't want to show the total running time
     attr_accessor :show_time
 
+    # Set to a valid file path if you want to save the output of the runners
+    # in a log file
+    attr_accessor :runner_log_file
+
     #
     # Search for the hydra config file
     def find_config_file
@@ -98,7 +102,8 @@ module Hydra #:nodoc:
         :autosort => @autosort,
         :files => @files,
         :listeners => @listeners,
-        :environment => @environment
+        :environment => @environment,
+        :runner_log_file => @runner_log_file
       }
       if @config
         @opts.merge!(:config => @config)

lib/hydra/worker.rb

@@ -28,6 +28,7 @@ module Hydra #:nodoc:
         listener = eval(l)
         @runner_event_listeners << listener if listener.is_a?(Hydra::RunnerListener::Abstract)
       end
+      @runner_log_file = opts.fetch(:runner_log_file) { nil }
 
       boot_runners(opts.fetch(:runners) { 1 })
       @io.write(Hydra::Messages::Worker::WorkerBegin.new)
@@ -91,7 +92,7 @@ module Hydra #:nodoc:
         pipe = Hydra::Pipe.new
         child = SafeFork.fork do
           pipe.identify_as_child
-          Hydra::Runner.new(:io => pipe, :verbose => @verbose, :runner_listeners => @runner_event_listeners )
+          Hydra::Runner.new(:io => pipe, :verbose => @verbose, :runner_listeners => @runner_event_listeners, :runner_log_file => @runner_log_file )
         end
         pipe.identify_as_parent
         @runners << { :pid => child, :io => pipe, :idle => false }

test/master_test.rb

@@ -273,8 +273,82 @@ class MasterTest < Test::Unit::TestCase
     end
   end
 
+  context "redirecting runner's output and errors" do
+    setup do
+      # avoid having other tests interfering with us
+      sleep(0.2)
+      FileUtils.rm_f(target_file)
+      FileUtils.rm_f(runner_log_file)
+      FileUtils.rm_f("#{remote_dir_path}/#{runner_log_file}")
+    end
+
+    teardown do
+      FileUtils.rm_f(target_file)
+      FileUtils.rm_f(runner_log_file)
+      FileUtils.rm_f("#{remote_dir_path}/#{runner_log_file}")
+    end
+
+    should "create a runner log file when usign local worker and passing a log file name" do
+      @pid = Process.fork do
+        Hydra::Master.new(
+              :files => [test_file],
+              :runner_log_file => runner_log_file,
+              :verbose => false
+            )
+      end
+      Process.waitpid @pid
+
+      assert_file_exists target_file # ensure the test was successfully ran
+      assert_file_exists runner_log_file
+    end
+
+    should "create a runner log file when usign remote worker and passing a log file name" do
+      @pid = Process.fork do
+        Hydra::Master.new(
+              :files => [test_file],
+              :workers => [{
+                :type => :ssh,
+                :connect => 'localhost',
+                :directory => remote_dir_path,
+                :runners => 1
+              }],
+              :verbose => false,
+              :runner_log_file => runner_log_file
+            )
+      end
+      Process.waitpid @pid
+
+      assert_file_exists target_file # ensure the test was successfully ran
+      assert_file_exists "#{remote_dir_path}/#{runner_log_file}"
+    end
+
+    # should "NOT create a runner log file when passing a incorrect log file path, but it should run successfully" do
+    #   @pid = Process.fork do
+    #     Hydra::Master.new(
+    #           :files => [test_file],
+    #           :workers => [{
+    #             :type => :ssh,
+    #             :connect => 'localhost',
+    #             :directory => remote_dir_path,
+    #             :runners => 1
+    #           }],
+    #           :verbose => false,
+    #           :runner_log_file => 'invalid-dir/runner.log'
+    #         )
+    #   end
+    #   Process.waitpid @pid
+
+    #   assert_file_exists target_file # ensure the test was successfully ran
+    #   assert_file_exists runner_log_file
+    # end
+  end
+
   private
 
+  def runner_log_file
+    "hydra_runner.log"
+  end
+
   def add_infinite_worker_begin_to master_listener
     class << master_listener
       def worker_begin( worker )