psltrie.rb

#!/usr/bin/env ruby
# Only used for tests
require 'simpleidn'

class PSLNode
  def initialize
    @children = {}
    @terminus = false
    @exception = false
  end

  def add_rule(x, excpt)
    lbl = x.shift
    if lbl.nil?
      raise 'Duplicate rule' if @terminus
      @terminus = true
      @exception = excpt
      return
    end
    @children[lbl] ||= PSLNode.new
    @children[lbl].add_rule(x, excpt)
  end

  def get_regdom(lbls, matched_lbls = [])
    lbl = lbls.shift
    if lbl.nil?
      return matched_lbls if @terminus && @exception
      return nil
    end
    return @children[lbl].get_regdom(lbls, matched_lbls << lbl) if @children.key?(lbl)
    return @children['*'].get_regdom(lbls, matched_lbls << lbl) if @children.key?('*')
    if @terminus
      return matched_lbls if @exception
      return matched_lbls << lbl
    end
    nil
  end

  def walk(prefix = '', &block)
    block.call(prefix, @exception) if @terminus
    @children.keys.sort.each do |label|
      @children[label].walk(label + '.' + prefix, &block)
    end
  end
end

class PSLTree
  def initialize
    @root = PSLNode.new
    # Default rule, as per spec
    @root.add_rule(['*'], false)
  end

  def add_rule(rulestr)
    exception = false
    if rulestr[0] == '!'
      exception = true
      rulestr = rulestr[1..-1]
    end
    lbls = rulestr.split('.').reverse
    @root.add_rule(lbls, exception)
  end

  def get_regdom(dom)
    dom.downcase!
    lbls = dom.split('.').reverse
    r = @root.get_regdom(lbls)
    return r if r.nil?
    r.reverse.join('.')
  end

  # walk and test are not used to in the core code
  def walk(&block)
    @root.walk(&block)
  end

  def test(input, expected)
    ex = SimpleIDN.to_unicode(expected)
    ex = nil if ex == 'null'

    rd = get_regdom(SimpleIDN.to_unicode(input))
    result = (rd == ex)
    puts "test(#{input}, #{expected}) = #{result} (#{rd})"
    result
  end
end

PRIVATE_DELIM = '===BEGIN PRIVATE DOMAINS==='.freeze
COMMENT_PREFIX = '//'.freeze
SPACE_RE = /\p{Space}/
SPACE_LINE = /\A\p{Space}*\z/

psl = PSLTree.new
privreg = false

## The Public Suffix List consists of a series of lines, separated by \n.
IO.foreach(ARGV[0], "\n") do |l|
  if !privreg && l.include?(PRIVATE_DELIM)
    privreg = true
    next
  end

  ## Each line is only read up to the first whitespace; entire lines can also be commented using //.
  ## Each line which is not entirely whitespace or begins with a comment contains a rule.

  next if l.start_with?(COMMENT_PREFIX)
  next if l =~ SPACE_LINE

  rule = l.split(SPACE_RE).first

  psl.add_rule(rule)
end

psl.walk do |n, expt|
  pfx = expt ? '!' : ''
  puts "#{pfx}#{n}"
end

null = nil

# The following applies to lines below this point.
# From: https://raw.githubusercontent.com/publicsuffix/list/master/tests/test_psl.txt
#   Any copyright is dedicated to the Public Domain.
#   https://creativecommons.org/publicdomain/zero/1.0/

# Mixed case.
psl.test('COM', null);
psl.test('example.COM', 'example.com');
psl.test('WwW.example.COM', 'example.com');
# Leading dot.
psl.test('.com', null);
psl.test('.example', null);
psl.test('.example.com', null);
psl.test('.example.example', null);
# Unlisted TLD.
psl.test('example', null);
psl.test('example.example', 'example.example');
psl.test('b.example.example', 'example.example');
psl.test('a.b.example.example', 'example.example');
# Listed, but non-Internet, TLD.
#checkPublicSuffix('local', null);
#checkPublicSuffix('example.local', null);
#checkPublicSuffix('b.example.local', null);
#checkPublicSuffix('a.b.example.local', null);
# TLD with only 1 rule.
psl.test('biz', null);
psl.test('domain.biz', 'domain.biz');
psl.test('b.domain.biz', 'domain.biz');
psl.test('a.b.domain.biz', 'domain.biz');
# TLD with some 2-level rules.
psl.test('com', null);
psl.test('example.com', 'example.com');
psl.test('b.example.com', 'example.com');
psl.test('a.b.example.com', 'example.com');
psl.test('uk.com', null);
psl.test('example.uk.com', 'example.uk.com');
psl.test('b.example.uk.com', 'example.uk.com');
psl.test('a.b.example.uk.com', 'example.uk.com');
psl.test('test.ac', 'test.ac');
# TLD with only 1 (wildcard) rule.
psl.test('mm', null);
psl.test('c.mm', null);
psl.test('b.c.mm', 'b.c.mm');
psl.test('a.b.c.mm', 'b.c.mm');
# More complex TLD.
psl.test('jp', null);
psl.test('test.jp', 'test.jp');
psl.test('www.test.jp', 'test.jp');
psl.test('ac.jp', null);
psl.test('test.ac.jp', 'test.ac.jp');
psl.test('www.test.ac.jp', 'test.ac.jp');
psl.test('kyoto.jp', null);
psl.test('test.kyoto.jp', 'test.kyoto.jp');
psl.test('ide.kyoto.jp', null);
psl.test('b.ide.kyoto.jp', 'b.ide.kyoto.jp');
psl.test('a.b.ide.kyoto.jp', 'b.ide.kyoto.jp');
psl.test('c.kobe.jp', null);
psl.test('b.c.kobe.jp', 'b.c.kobe.jp');
psl.test('a.b.c.kobe.jp', 'b.c.kobe.jp');
psl.test('city.kobe.jp', 'city.kobe.jp');
psl.test('www.city.kobe.jp', 'city.kobe.jp');
# TLD with a wildcard rule and exceptions.
psl.test('ck', null);
psl.test('test.ck', null);
psl.test('b.test.ck', 'b.test.ck');
psl.test('a.b.test.ck', 'b.test.ck');
psl.test('www.ck', 'www.ck');
psl.test('www.www.ck', 'www.ck');
# US K12.
psl.test('us', null);
psl.test('test.us', 'test.us');
psl.test('www.test.us', 'test.us');
psl.test('ak.us', null);
psl.test('test.ak.us', 'test.ak.us');
psl.test('www.test.ak.us', 'test.ak.us');
psl.test('k12.ak.us', null);
psl.test('test.k12.ak.us', 'test.k12.ak.us');
psl.test('www.test.k12.ak.us', 'test.k12.ak.us');
# IDN labels.
psl.test('食狮.com.cn', '食狮.com.cn');
psl.test('食狮.公司.cn', '食狮.公司.cn');
psl.test('www.食狮.公司.cn', '食狮.公司.cn');
psl.test('shishi.公司.cn', 'shishi.公司.cn');
psl.test('公司.cn', null);
psl.test('食狮.中国', '食狮.中国');
psl.test('www.食狮.中国', '食狮.中国');
psl.test('shishi.中国', 'shishi.中国');
psl.test('中国', null);
# Same as above, but punycoded.
psl.test('xn--85x722f.com.cn', 'xn--85x722f.com.cn');
psl.test('xn--85x722f.xn--55qx5d.cn', 'xn--85x722f.xn--55qx5d.cn');
psl.test('www.xn--85x722f.xn--55qx5d.cn', 'xn--85x722f.xn--55qx5d.cn');
psl.test('shishi.xn--55qx5d.cn', 'shishi.xn--55qx5d.cn');
psl.test('xn--55qx5d.cn', null);
psl.test('xn--85x722f.xn--fiqs8s', 'xn--85x722f.xn--fiqs8s');
psl.test('www.xn--85x722f.xn--fiqs8s', 'xn--85x722f.xn--fiqs8s');
psl.test('shishi.xn--fiqs8s', 'shishi.xn--fiqs8s');
psl.test('xn--fiqs8s', null);

psl.test("www.goog", "goog")