First version.

Author: gkellogg

.gitignore

@@ -1,3 +1,4 @@
+.DS_Store
 *.gem
 *.rbc
 /.config
@@ -9,6 +10,7 @@
 /test/tmp/
 /test/version_tmp/
 /tmp/
+benchmark/
 
 # Used by dotenv library to load environment variables.
 # .env
@@ -42,9 +44,11 @@ build-iPhoneSimulator/
 
 # for a library or gem, you might want to ignore these files since the code is
 # intended to run in multiple environments; otherwise, check them in:
-# Gemfile.lock
-# .ruby-version
-# .ruby-gemset
+Gemfile.lock
+.ruby-version
+.ruby-gemset
 
 # unless supporting rvm < 1.11.0 or doing something fancy, ignore this:
 .rvmrc
+/.byebug_history
+/.yardopts

Gemfile

@@ -0,0 +1,13 @@
+source "https://rubygems.org"
+gemspec
+
+group :development, :test do
+  gem 'simplecov',  require: false, platform: :mri
+  gem 'coveralls',  require: false, platform: :mri
+  gem 'benchmark-ips'
+  gem 'rake'
+end
+
+group :debug do
+  gem "byebug", platforms: :mri
+end

README.md

@@ -1,2 +1,88 @@
 # json-canonicalization
 An implementation of the JSON Canonicalization Scheme for Ruby
+
+Implements version 5 of [draft-rundgren-json-canonicalization-scheme-05](https://tools.ietf.org/html/draft-rundgren-json-canonicalization-scheme-05#page-5).
+
+# Description
+
+Cryptographic operations like hashing and signing depend on that the target 
+data does not change during serialization, transport, or parsing. 
+By applying the rules defined by JCS (JSON Canonicalization Scheme), 
+data provided in the JSON [[RFC8259](https://tools.ietf.org/html/rfc8259)]
+format can be exchanged "as is", while still being subject to secure cryptographic operations.
+JCS achieves this by building on the serialization formats for JSON
+primitives as defined by ECMAScript [[ES6](https://www.ecma-international.org/ecma-262/6.0/index.html)],
+constraining JSON data to the<br>I-JSON [[RFC7493](https://tools.ietf.org/html//rfc7493)] subset,
+and through a platform independent property sorting scheme.
+
+Working document: https://cyberphone.github.io/ietf-json-canon<br>
+Published IETF Draft: https://tools.ietf.org/html/draft-rundgren-json-canonicalization-scheme-05
+
+The JSON Canonicalization Scheme concept in a nutshell:
+- Serialization of primitive JSON data types using methods compatible with ECMAScript's `JSON.stringify()`
+- Lexicographic sorting of JSON `Object` properties in a *recursive* process
+- JSON `Array` data is also subject to canonicalization, *but element order remains untouched*
+
+### Sample Input:
+```code
+{
+  "numbers": [333333333.33333329, 1E30, 4.50, 2e-3, 0.000000000000000000000000001],
+  "string": "\u20ac$\u000F\u000aA'\u0042\u0022\u005c\\\"\/",
+  "literals": [null, true, false]
+}
+```
+### Expected Output:
+```code
+{"literals":[null,true,false],"numbers":[333333333.3333333,1e+30,4.5,0.002,1e-27],"string":"€$\u000f\nA'B\"\\\\\"/"}
+```
+## Usage
+The library accepts Ruby input and generates canonical JSON via the `#to_json_c14n` method. This is based on the standard JSON gem's version of `#to_json` with overloads for `Hash`, `String` and `Numeric`
+
+```ruby
+data = {
+  "numbers" => [
+    333333333.3333333,
+    1.0e+30,
+    4.5,
+    0.002,
+    1.0e-27
+  ],
+  "string" => "€$\u000F\nA'B\"\\\\\"/",
+  "literals" => [nil, true, false]
+}
+
+puts data.to_json_c14n
+=> 
+```
+
+## Documentation
+Full documentation available on [RubyDoc](http://rubydoc.info/gems/json-canonicalization/file/README.md)
+
+### Principal Classes
+* {JSON::Canonicalization}
+
+## Dependencies
+* [Ruby](http://ruby-lang.org/) (>= 2.2.2)
+* [JSON](https://rubygems.org/gems/json) (>= 2.1)
+
+## Author
+* [Gregg Kellogg](http://github.com/gkellogg) - <http://kellogg-assoc.com/>
+
+## Contributing
+* Do your best to adhere to the existing coding conventions and idioms.
+* Don't use hard tabs, and don't leave trailing whitespace on any line.
+* Do document every method you add using [YARD][] annotations. Read the
+  [tutorial][YARD-GS] or just look at the existing code for examples.
+* Don't touch the `json-ld.gemspec`, `VERSION` or `AUTHORS` files. If you need to
+  change them, do so on your private branch only.
+* Do feel free to add yourself to the `CREDITS` file and the corresponding
+  list in the the `README`. Alphabetical order applies.
+* Do note that in order for us to merge any non-trivial changes (as a rule
+  of thumb, additions larger than about 15 lines of code), we need an
+  explicit [public domain dedication][PDD] on record from you.
+
+##License
+
+This is free and unencumbered public domain software. For more information,
+see <http://unlicense.org/> or the accompanying {file:UNLICENSE} file.
+

VERSION

@@ -0,0 +1,6 @@
+{
+ "numbers": [333333333.33333329, 1E30, 4.50,
+             2e-3, 0.000000000000000000000000001],
+ "string": "\u20ac$\u000F\u000aA'\u0042\u0022\u005c\\\"\/",
+ "literals": [null, true, false]
+}

examples/c14n.json

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+#!/usr/bin/env ruby -rubygems
+# -*- encoding: utf-8 -*-
+
+Gem::Specification.new do |gem|
+  gem.version               = File.read('VERSION').chomp
+  gem.date                  = File.mtime('VERSION').strftime('%Y-%m-%d')
+
+  gem.name                  = "json-canonicalization"
+  gem.homepage              = "http://github.com/dryruby/json-canonicalization"
+  gem.license               = 'Unlicense'
+  gem.summary               = "JSON Canonicalization for Ruby."
+  gem.description           = "JSON::Canonicalization generates canonical JSON output from Ruby objects."
+
+  gem.authors               = ['Gregg Kellogg']
+
+  gem.platform              = Gem::Platform::RUBY
+  gem.files                 = %w(AUTHORS README.md UNLICENSE VERSION) + Dir.glob('lib/**/*.rb')
+  gem.test_files            = Dir.glob('spec/**/*.rb') + Dir.glob('spec/**/*.json')
+
+  gem.required_ruby_version = '>= 2.2.2'
+  gem.requirements          = []
+  gem.add_development_dependency 'rspec',           '~> 3.8'
+  gem.add_development_dependency 'yard' ,           '~> 0.9'
+
+  gem.post_install_message  = nil
+end

json-canonicalization.gemspec

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+# -*- encoding: utf-8 -*-
+# frozen_string_literal: true
+$:.unshift(File.expand_path("../ld", __FILE__))
+require 'json'
+
+module JSON
+  ##
+  # `JSON::Canonicalization` generates canonical JSON output from Ruby objects
+  module Canonicalization
+    autoload :VERSION,            'json/ld/version'
+  end
+end
+
+class Object
+  # Default canonicalization output for Ruby objects
+  # @return [String]
+  def to_json_c14n
+    self.to_json
+  end
+end
+
+class Array
+  def to_json_c14n
+    '[' + self.map(&:to_json_c14n).join(',') + ']'
+  end
+end
+
+class Numeric
+  def to_json_c14n
+    raise RangeError if self.is_a?(Float) && (self.nan? || self.infinite?)
+    return "0" if self.zero?
+    num = self
+    if num < 0
+      num, sign = -num, '-'
+    end
+    native_rep = "%.15E" % num
+    decimal, exponential = native_rep.split('E')
+    exp_val = exponential.to_i
+    exponential = exp_val > 0 ? ('+' + exp_val.to_s) : exp_val.to_s
+
+    integral, fractional = decimal.split('.')
+    fractional = fractional.sub(/0+$/, '')  # Remove trailing zeros
+
+    if exp_val > 0 && exp_val < 21
+      while exp_val > 0
+        integral += fractional.to_s[0] || '0'
+        fractional = fractional.to_s[1..-1]
+        exp_val -= 1
+      end
+      exponential = nil
+    elsif exp_val == 0
+      exponential = nil
+    elsif exp_val < 0 && exp_val > -7
+      # Small numbers are shown as 0.etc with e-6 as lower limit
+      fractional, integral, exponential = integral + fractional.to_s, '0', nil
+      fractional = ("0" * (-exp_val - 1)) + fractional
+    end
+
+    fractional = nil if fractional.to_s.empty?
+    sign.to_s + integral + (fractional ? ".#{fractional}" : '') + (exponential ? "e#{exponential}" : '')
+  end
+end
+
+class Hash
+  # Output JSON with keys sorted lexicographically
+  # @return [String]
+  def to_json_c14n
+    "{" + self.
+      keys.
+      sort_by {|k| k.encode(Encoding::UTF_16)}.
+      map {|k| k.to_json_c14n + ':' + self[k].to_json_c14n}
+      .join(',') +
+    '}'
+  end
+end
+
+class String
+  # Output JSON with control characters escaped
+  # @return [String]
+  def to_json_c14n
+    self.to_json
+  end
+end

lib/json/canonicalization.rb

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+# -*- encoding: utf-8 -*-
+# frozen_string_literal: true
+module JSON::Canonicalization::VERSION
+  VERSION_FILE = File.join(File.expand_path(File.dirname(__FILE__)), "..", "..", "..", "VERSION")
+  MAJOR, MINOR, TINY, EXTRA = File.read(VERSION_FILE).chomp.split(".")
+
+  STRING = [MAJOR, MINOR, TINY, EXTRA].compact.join('.')
+
+  ##
+  # @return [String]
+  def self.to_s()   STRING end
+
+  ##
+  # @return [String]
+  def self.to_str() STRING end
+
+  ##
+  # @return [Array(Integer, Integer, Integer)]
+  def self.to_a() STRING.split(".") end
+end

lib/json/canonicalization/version.rb

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+require_relative 'spec_helper'
+
+describe "conversions" do
+  Dir.glob(File.expand_path("../input/*.json", __FILE__)).each do |input|
+    it "converts #{input.split('/').last}" do
+      expected = File.read(input.sub('input', 'output'))
+      data = JSON.parse(File.read(input))
+      expect(data.to_json_c14n).to eq expected
+    end
+  end
+end

spec/c14n_spec.rb

@@ -0,0 +1,8 @@
+[
+  56,
+  {
+    "d": true,
+    "10": null,
+    "1": [ ]
+  }
+]