Ruby bindings for brotli library

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See brotli library.

Installation

Please install brotli library first, use latest 1.0.0+ version.

gem install ruby-brs

You can build it from source.

rake gem
gem install pkg/ruby-brs-*.gem

Usage

There are simple APIs: String and File. Also you can use generic streaming API: Stream::Writer and Stream::Reader.

require "brs"

data = BRS::String.compress "sample string"
puts BRS::String.decompress(data)

BRS::File.compress "file.txt", "file.txt.br"
BRS::File.decompress "file.txt.br", "file.txt"

BRS::Stream::Writer.open("file.txt.br") { |writer| writer << "sample string" }
puts BRS::Stream::Reader.open("file.txt.br") { |reader| reader.read }

You can create and read tar.br archives with minitar for example.

require "brs"
require "minitar"

BRS::Stream::Writer.open "file.tar.br" do |writer|
  Minitar::Writer.open writer do |tar|
    tar.add_file_simple "file", :data => "sample string"
  end
end

BRS::Stream::Reader.open "file.tar.br" do |reader|
  Minitar::Reader.open reader do |tar|
    tar.each_entry do |entry|
      puts entry.name
      puts entry.read
    end
  end
end

Options

Each API supports several options:

:source_buffer_length
:destination_buffer_length

There are internal buffers for compressed and decompressed data. For example you want to use 1 KB as source buffer length for compressor - please use 256 B as destination buffer length. You want to use 256 B as source buffer length for decompressor - please use 1 KB as destination buffer length.

Values: 0 - infinity, default value: 0. 0 means automatic buffer length selection.

:mode

Values: BRS::Option::MODES, default value: :generic.

:quality

Values: BRS::Option::MIN_QUALITY - BRS::Option::MAX_QUALITY, default value: BRS::Option::MAX_QUALITY.

:lgwin

Values: BRS::Option::MIN_LGWIN - BRS::Option::MAX_LGWIN, default value: 22.

:lgblock

Values: BRS::Option::MIN_LGBLOCK - BRS::Option::MAX_LGBLOCK, default value: none.

:disable_literal_context_modeling

Values: true/false, default value: false.

:disable_ring_buffer_reallocation

Values: true/false, default value: false.

:size_hint

Values: 0 - infinity, default value: 0. It is reasonable to provide size of input (if known) for streaming api. String and File will set :size_hint automaticaly.

:large_window

Values: true/false, default value: false.

Please read brotli docs for more info about options.

Possible compressor options:

:mode
:quality
:lgwin
:lgblock
:disable_literal_context_modeling
:size_hint
:large_window

Possible decompressor options:

:disable_ring_buffer_reallocation
:large_window

Example:

require "brs"

data = BRS::String.compress "sample string", :quality => 5
puts BRS::String.decompress(data, :disable_ring_buffer_reallocation => true)

HTTP encoding (Content-Encoding: br) using default options:

require "brs"
require "sinatra"

get "/" do
  headers["Content-Encoding"] = "br"
  BRS::String.compress "sample string"
end

String

String maintains destination buffer only, so it accepts destination_buffer_length option only.

::compress(source, options = {})
::decompress(source, options = {})

source is a source string.

File

File maintains both source and destination buffers, it accepts both source_buffer_length and destination_buffer_length options.

::compress(source, destination, options = {})
::decompress(source, destination, options = {})

source and destination are file pathes.

Stream::Writer

Its behaviour is similar to builtin Zlib::GzipWriter.

Writer maintains destination buffer only, so it accepts destination_buffer_length option only.

::open(file_path, options = {}, :external_encoding => nil, :transcode_options => {}, &block)

Open file path and create stream writer associated with opened file. Data will be transcoded to :external_encoding using :transcode_options before compressing.

It may be tricky to use both :size_hint and :transcode_options. You have to provide size of transcoded input.

::new(destination_io, options = {}, :external_encoding => nil, :transcode_options => {})

Create stream writer associated with destination io. Data will be transcoded to :external_encoding using :transcode_options before compressing.

It may be tricky to use both :size_hint and :transcode_options. You have to provide size of transcoded input.

#set_encoding(external_encoding, nil, transcode_options)

Set another encodings, nil is just for compatibility with IO.

#io
#to_io
#stat
#external_encoding
#transcode_options
#pos
#tell

See IO docs.

#write(*objects)
#flush
#rewind
#close
#closed?

See Zlib::GzipWriter docs.

#write_nonblock(object, *options)
#flush_nonblock(*options)
#rewind_nonblock(*options)
#close_nonblock(*options)

Special asynchronous methods missing in Zlib::GzipWriter. rewind wants to close, close wants to write something and flush, flush want to write something. So it is possible to have asynchronous variants for these synchronous methods. Behaviour is the same as IO#write_nonblock method.

#<<(object)
#print(*objects)
#printf(*args)
#putc(object, encoding: ::Encoding::BINARY)
#puts(*objects)

Typical helpers, see Zlib::GzipWriter docs.

Stream::Reader

Its behaviour is similar to builtin Zlib::GzipReader.

Reader maintains both source and destination buffers, it accepts both source_buffer_length and destination_buffer_length options.

::open(file_path, options = {}, :external_encoding => nil, :internal_encoding => nil, :transcode_options => {}, &block)

Open file path and create stream reader associated with opened file. Data will be force encoded to :external_encoding and transcoded to :internal_encoding using :transcode_options after decompressing.

::new(source_io, options = {}, :external_encoding => nil, :internal_encoding => nil, :transcode_options => {})

Create stream reader associated with source io. Data will be force encoded to :external_encoding and transcoded to :internal_encoding using :transcode_options after decompressing.

#set_encoding(external_encoding, internal_encoding, transcode_options)

Set another encodings.

#io
#to_io
#stat
#external_encoding
#internal_encoding
#transcode_options
#pos
#tell

See IO docs.

#read(bytes_to_read = nil, out_buffer = nil)
#eof?
#rewind
#close
#closed?

See Zlib::GzipReader docs.

#readpartial(bytes_to_read = nil, out_buffer = nil)
#read_nonblock(bytes_to_read, out_buffer = nil, *options)

See IO docs.

#getbyte
#each_byte(&block)
#readbyte
#ungetbyte(byte)

#getc
#readchar
#each_char(&block)
#ungetc(char)

#lineno
#lineno=
#gets(separator = $OUTPUT_RECORD_SEPARATOR, limit = nil)
#readline
#readlines
#each(&block)
#each_line(&block)
#ungetline(line)

Typical helpers, see Zlib::GzipReader docs.

CI

See universal test script scripts/ci_test.sh for CI. Please visit scripts/test-images. You can run this test script using many native and cross images.

Cirrus CI uses x86_64-pc-linux-gnu image, Circle CI - x86_64-gentoo-linux-musl image.

License

MIT license, see LICENSE and AUTHORS.