Topic: merge Add a sink for writing to stdout/stderr. (add topic merge)

Test plan:
Added unit tests.

Change-Id: I4460f158ef153b2ce3db25e74f01d5448833c8c5

vcap_logging/lib/vcap/logging/sink.rb

@@ -1,3 +1,4 @@
 require 'vcap/logging/sink/base_sink'
 require 'vcap/logging/sink/file_sink'
+require 'vcap/logging/sink/stdio_sink'
 require 'vcap/logging/sink/syslog_sink'

vcap_logging/lib/vcap/logging/sink/stdio_sink.rb

@@ -0,0 +1,40 @@
+require 'vcap/logging/sink/base_sink'
+
+module VCAP::Logging::Sink
+
+  # A sink for writing to stderr/stdout
+  # Usage:
+  #   stdout_sink = VCAP::Logging::Sink::StdioSink.new(STDOUT)
+  #
+  class StdioSink < BaseSink
+    def initialize(io, formatter=nil)
+      super(formatter)
+      @io  = io
+      @out = nil
+      open
+    end
+
+    def open
+      @mutex.synchronize do
+        @opened = true
+        @out = @io
+      end
+    end
+
+    def close
+      @mutex.synchronize do
+        @opened = false
+        @out = nil
+      end
+    end
+
+    private
+
+    def write(message)
+      @mutex.synchronize do
+        @io.write(message)
+      end
+    end
+
+  end
+end

vcap_logging/spec/unit/stdio_sink_spec.rb

@@ -0,0 +1,20 @@
+require File.join(File.dirname(__FILE__), '..', 'spec_helper')
+
+describe VCAP::Logging::Sink::StdioSink do
+  it 'should not close the underlying io object when closed' do
+    io = mock(:stdout)
+    io.should_not_receive(:close)
+    sink = VCAP::Logging::Sink::StdioSink.new(io)
+    sink.close
+  end
+
+  it 'should write formatted messages to the underlying io device' do
+    msg = 'test log message'
+    fmt = mock(:formatter)
+    fmt.should_receive(:format_record).with(nil).and_return(msg)
+    io = mock(:stdio)
+    io.should_receive(:write).with(msg)
+    sink = VCAP::Logging::Sink::StdioSink.new(io, fmt)
+    sink.add_record(nil)
+  end
+end