Files

Lumberjack::Device::Writer

This logging device writes log entries as strings to an IO stream. By default, messages will be buffered and written to the stream in a batch when the buffer is full or when flush is called.

Attributes

buffer_size[R]

The size of the internal buffer. Defaults to 32K.

Public Class Methods

new(stream, options = {}) click to toggle source

Create a new device to write log entries to a stream. Entries are converted to strings using a Template. The template can be specified using the :template option. This can either be a Proc or a string that will compile into a Template object.

If the template is a Proc, it should accept an LogEntry as its only argument and output a string.

If the template is a template string, it will be used to create a Template. The :additional_lines and :time_format options will be passed through to the Template constuctor.

The default template is "[:time :severity :progname(:pid) #:unit_of_work_id] :message" with additional lines formatted as "\n [#:unit_of_work_id] :message". The unit of work id will only appear if it is present.

The size of the internal buffer in bytes can be set by providing :buffer_size (defaults to 32K).

# File lib/lumberjack/device/writer.rb, line 55
def initialize(stream, options = {})
  @lock = Mutex.new
  @stream = stream
  @stream.sync = true if @stream.respond_to?(:sync=)
  @buffer = Buffer.new
  @buffer_size = (options[:buffer_size] || 0)
  template = (options[:template] || DEFAULT_FIRST_LINE_TEMPLATE)
  if template.respond_to?(:call)
    @template = template
  else
    additional_lines = (options[:additional_lines] || DEFAULT_ADDITIONAL_LINES_TEMPLATE)
    @template = Template.new(template, :additional_lines => additional_lines, :time_format => options[:time_format])
  end
end

Public Instance Methods

buffer_size=(value) click to toggle source

Set the buffer size in bytes. The device will only be physically written to when the buffer size is exceeded.

# File lib/lumberjack/device/writer.rb, line 72
def buffer_size=(value)
  @buffer_size = value
  flush
end
close() click to toggle source

Close the underlying stream.

# File lib/lumberjack/device/writer.rb, line 87
def close
  flush
  stream.close
end
flush() click to toggle source

Flush the underlying stream.

# File lib/lumberjack/device/writer.rb, line 93
def flush
  @lock.synchronize do
    before_flush
    unless @buffer.empty?
      out = @buffer.join(Lumberjack::LINE_SEPARATOR) << Lumberjack::LINE_SEPARATOR
      begin
        stream.write(out)
        stream.flush
      rescue => e
        $stderr.write("#{e.class.name}: #{e.message}#{' at ' + e.backtrace.first if e.backtrace}")
        $stderr.write(out)
        $stderr.flush
      end
      @buffer.clear
    end
  end
end
write(entry) click to toggle source

Write an entry to the stream. The entry will be converted into a string using the defined template.

# File lib/lumberjack/device/writer.rb, line 78
def write(entry)
  string = @template.call(entry)
  @lock.synchronize do
    @buffer << string
  end
  flush if @buffer.size >= buffer_size
end

Protected Instance Methods

before_flush() click to toggle source

Callback method that will be executed before data is written to the stream. Subclasses can override this method if needed.

# File lib/lumberjack/device/writer.rb, line 115
def before_flush
end
stream() click to toggle source

Get the underlying stream.

# File lib/lumberjack/device/writer.rb, line 124
def stream
  @stream
end
stream=(stream) click to toggle source

Set the underlying stream.

# File lib/lumberjack/device/writer.rb, line 119
def stream=(stream)
  @stream = stream
end

[Validate]

Generated with the Darkfish Rdoc Generator 2.