libcbor

The Ruby bindings for libcbor. Provides CBOR encoding and decoding features, including streaming.

Important resources

Installation

Make sure that libffi-dev and libcbor are present on your system.

Add this line to your application's Gemfile:

gem 'libcbor'

And then execute:

$ bundle

Or install it yourself as:

$ gem install libcbor

Usage

Include the library using

include 'libcbor/all'

You can then encode objects

{ 'key' => 42 }.to_cbor
# => "\xA1ckey\x18*"

... as well as decode serialized data

CBOR.decode("\xA1ckey\x18*")
# => {"key"=>42}

libcbor also comes with streaming features. When decoding, you can specify callbacks and handle the input as desired. The following example illustrates how to integrate libcbor with EventMachine:

#!/usr/bin/env ruby

# Listens for connections, asynchronously receives data, replies with
# pretty-printed arrays (works for indefinite arrays with integers only for
# the sake of simplicity)
#
# Make sure to install EventMachine first (`$ gem install eventmachine`)
#
# Start with
# $ ./examples/network_streaming.rb
#
# Then send data from the example file using netcat or a similar tool:
# $ netcat localhost 9000 < examples/data/indef_array.cbor
#
# The file from the example contains the CBOR representation of
#   [_ [_ 1, 2], 3, [_ 4, [_ 5]]]
# Terminate with ^c

$LOAD_PATH.unshift(File.join(File.dirname(__FILE__), '..'))
require 'lib/libcbor'
require 'rubygems'
require 'eventmachine'

class CBORPrinter < EM::Connection
    def print(what)
        send_data('  ' * @nesting + what.to_s + "\n")
    end

    def initialize
        @nesting = 0
        @reader = CBOR::Streaming::BufferedDecoder.new(
            array_start: ->() { print '['; @nesting += 1 },
            integer: ->(val) { print val },
            break: ->() {
                @nesting -= 1; print ']'
                close_connection_after_writing if @nesting == 0
            }
        )
    end

    def receive_data(data)
        @reader << data
    end
end

EventMachine.run do
    Signal.trap('INT')  { EventMachine.stop }
    EventMachine.start_server('0.0.0.0', 9000, CBORPrinter)
end

Streaming encoding is possible as well. Check out the examples directory and the documentation for more examples.

Development

After checking out the repo, run bin/setup to install dependencies. Then, run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install.

Contributing

Fork it ( https://github.com/[my-github-username]/libcbor/fork )
Create your feature branch (git checkout -b my-new-feature)
Commit your changes (git commit -am 'Add some feature')
Push to the branch (git push origin my-new-feature)
Create a new Pull Request

License

The MIT License (MIT)

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.