module Fluent::Plugin::Compressable

Public Instance Methods

compress(data, **kwargs) click to toggle source
# File lib/fluent/plugin/compressable.rb, line 23
def compress(data, **kwargs)
  output_io = kwargs[:output_io]
  io = output_io || StringIO.new
  Zlib::GzipWriter.wrap(io) do |gz|
    gz.write data
  end

  output_io || io.string
end
decompress(compressed_data = nil, output_io: nil, input_io: nil) click to toggle source

compressed_data is String like `compress(data1) + compress(data2) + … + compress(dataN)` www.ruby-forum.com/topic/971591#979503

# File lib/fluent/plugin/compressable.rb, line 35
def decompress(compressed_data = nil, output_io: nil, input_io: nil)
  case
  when input_io && output_io
    io_decompress(input_io, output_io)
  when input_io
    output_io = StringIO.new
    io = io_decompress(input_io, output_io)
    io.string
  when compressed_data.nil? || compressed_data.empty?
    # check compressed_data(String) is 0 length
    compressed_data
  when output_io
    # exeucte after checking compressed_data is empty or not
    io = StringIO.new(compressed_data)
    io_decompress(io, output_io)
  else
    string_decompress(compressed_data)
  end
end

Private Instance Methods

io_decompress(input, output) click to toggle source
# File lib/fluent/plugin/compressable.rb, line 75
def io_decompress(input, output)
  loop do
    gz = Zlib::GzipReader.new(input)
    v = gz.read
    output.write(v)
    unused = gz.unused
    gz.finish

    break if unused.nil?
    adjust = unused.length
    input.pos -= adjust
  end

  output
end
string_decompress(compressed_data) click to toggle source
# File lib/fluent/plugin/compressable.rb, line 57
def string_decompress(compressed_data)
  io = StringIO.new(compressed_data)

  out = ''
  loop do
    gz = Zlib::GzipReader.new(io)
    out << gz.read
    unused = gz.unused
    gz.finish

    break if unused.nil?
    adjust = unused.length
    io.pos -= adjust
  end

  out
end