Mixlib::ShellOut live stream reader in Chef

shell_out.rb

# Only for Chef client 11 family!
# Bug was fixed in https://github.com/opscode/chef/commit/d6f6928fd1097709189cd78689e89032d4c9318d

class Chef
  module Mixin
    module ShellOut
      def shell_out(*command_args)
        cmd = Mixlib::ShellOut.new(*run_command_compatible_options(command_args))
        cmd.live_stream ||= io_for_live_stream
        cmd.run_command
        cmd
      end
    end
  end
end

stream_reader.rb

# See also https://gist.github.com/kwilczynski/2c68a486e230433d8cd2

class Chef
  class Recipe
    class StreamReader
      require 'stringio'
      
      def initialize(&block)
        @block = block
        @buffer = StringIO.new
        @buffer.sync = true if @buffer.respond_to?(:sync)
      end
      
      def <<(chunk)
        overflow = ''
        
        @buffer.write(chunk)
        @buffer.rewind
        
        @buffer.each_line do |line|
          if line.match(/\r?\n/)
            @block.call(line.strip)
          else
            overflow = line
          end
        end

        @buffer.truncate(@buffer.rewind)
        @buffer.write(overflow)
      end
    end
  end
end

stream_reader = StreamReader.new do |line|
  Chef::Log.info(line)
end
 
  include Chef::Mixin::ShellOut
 
ruby_block 'list current directory' do
  block do
    Chef::Resource::RubyBlock.send(:include, Chef::Mixin::ShellOut)
    shell_out!('ls -l', :live_stream => stream_reader)
  end
end