Multicodecs

Canonical table of of codecs used by various multiformats

Multicodecs is the ruby implementation of [multiformats/multicodec][spec].

🙌🏽 This is called multicodecs instead of the singular form, to stay consistent with the multihashes gem, which was forced to take a different name has multihash was already taken, which is also the case for multibase and others. In the future, this might be renamed to multiformats-codec, with a backwards-compatible interface.

Installation

Add this line to your application's Gemfile:

gem 'multicodecs', require: false

Or if you want to autoload the last known table:

gem 'multicodecs'

Or if you want the PORO without any values:

gem 'multicodecs', require: 'multicodecs/bare'

And then execute:

$ bundle

Or install it yourself as:

$ gem install multicodecs

Usage

This is just a codec, not a protocol. This means that this gem only provides a nice-to-use mapping from the [single source of truth][table] to a PORO. It also allows you to bring your own values.

require 'multicodecs'

Multicodecs['identity']
# => #<struct Multicodecs::Registration code=0, name="identity", tag="multihash">

Multicodecs[0x12]
# => #<struct Multicodecs::Registration code=18, name="sha2-256", tag="multihash">

Multicodecs.find_by(name: 'protobuf')
# => #<struct Multicodecs::Registration code=80, name="protobuf", tag="serialization">

You can register your own values

Multicodecs.register(code: 0x12345, name: 'xxx', tag: 'vendor')
# => #<struct Multicodecs::Registration code=74565, name="xxx", tag="vendor">

Convenience methods exist:

Multicodecs.names: returns all the known names
Multicodecs.codes: returns all the known codes
Multicodecs.find_by(code: nil, name: nil): same as []
Multicodecs.fetch_by!(code: nil, name: nil): same as [] but errors if not found
Multicodecs.load_csv(csv, radix: 16): loads table.csv like data

[multiformats/multicodec][git-multicodec]: the spec repository
[multiformats/ruby-multiaddr][git-ruby-multiaddr]: the ruby implementation of [multiformats/multiaddr][git-multiaddr]
[multiformats/ruby-multibase][git-ruby-multibase]: the ruby implementation of [multiformats/multibase][git-multibase]
[multiformats/ruby-multihash][git-ruby-multihash]: the ruby implementation of [multiformats/multihash][git-multihash]

Development

After checking out the repo, run bin/setup to install dependencies. Then, run rake test to run the tests. You can also 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. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to [rubygems.org][web-rubygems].

Updating the table

The Rakefile provides an easy way of updating the table.csv, using a rake command.

rake update
# => updated lib/table.csv

Contributing

Bug reports and pull requests are welcome on GitHub at [SleeplessByte/ruby-multicodec][git-self]. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the [Contributor Covenant][web-coc] code of conduct.

License

The gem is available as open source under the terms of the [MIT License][web-mit].

Code of Conduct

Everyone interacting in this project’s codebases, issue trackers, chat rooms and mailing lists is expected to follow the [code of conduct][git-self-coc].