class PublicSuffix::Rule::Base

Abstract rule class¶ ↑

This represent the base class for a Rule definition in the Public Suffix List.

This is intended to be an Abstract class and you shouldn’t create a direct instance. The only purpose of this class is to expose a common interface for all the available subclasses.

{PublicSuffix::Rule::Normal}
{PublicSuffix::Rule::Exception}
{PublicSuffix::Rule::Wildcard}

## Properties

A rule is composed by 4 properties:

value - A normalized version of the rule name.

The normalization process depends on rule tpe.

Here’s an example

PublicSuffix::Rule.factory("*.google.com")
#<PublicSuffix::Rule::Wildcard:0x1015c14b0
    @value="google.com"
>

## Rule Creation

The best way to create a new rule is passing the rule name to the PublicSuffix::Rule.factory method.

PublicSuffix::Rule.factory("com")
# => PublicSuffix::Rule::Normal

PublicSuffix::Rule.factory("*.com")
# => PublicSuffix::Rule::Wildcard

This method will detect the rule type and create an instance from the proper rule class.

## Rule Usage

A rule describes the composition of a domain name and explains how to tokenize the name into tld, sld and trd.

To use a rule, you first need to be sure the name you want to tokenize can be handled by the current rule. You can use the match? method.

rule = PublicSuffix::Rule.factory("com")

rule.match?("google.com")
# => true

rule.match?("google.com")
# => false

Rule order is significant. A name can match more than one rule. See the Public Suffix Documentation to learn more about rule priority.

When you have the right rule, you can use it to tokenize the domain name.

rule = PublicSuffix::Rule.factory("com")

rule.decompose("google.com")
# => ["google", "com"]

rule.decompose("www.google.com")
# => ["www.google", "com"]

@abstract

Attributes

length [R]

@return [String] the length of the rule

private [R]

@return [Boolean] true if the rule is a private domain

value [R]

@return [String] the rule definition

Public Class Methods

build (content, private: false)

Initializes a new rule from the content.

@param content [String] the content of the rule @param private [Boolean]

# File lib/public_suffix/rule.rb, line 118
def self.build(content, private: false)
  new(value: content, private: private)
end

new (value:, length: nil, private: false)

Initializes a new rule.

@param value [String] @param private [Boolean]

# File lib/public_suffix/rule.rb, line 126
def initialize(value:, length: nil, private: false)
  @value    = value.to_s
  @length   = length || (@value.count(DOT) + 1)
  @private  = private
end

Public Instance Methods

== (other)

Checks whether this rule is equal to other.

@param other [PublicSuffix::Rule::*] The rule to compare @return [Boolean] true if this rule and other are instances of the same class

and has the same value, false otherwise.

# File lib/public_suffix/rule.rb, line 137
def ==(other)
  equal?(other) || (self.class == other.class && value == other.value)
end

Also aliased as: eql?

decompose (*)

@abstract @param domain [#to_s] The domain name to decompose @return [Array<String, nil>]

# File lib/public_suffix/rule.rb, line 180
def decompose(*)
  raise NotImplementedError
end

eql? (other)

Alias for: ==

match? (name)

Checks if this rule matches name.

A domain name is said to match a rule if and only if all of the following conditions are met:

When the domain and rule are split into corresponding labels, that the domain contains as many or more labels than the rule.
Beginning with the right-most labels of both the domain and the rule, and continuing for all labels in the rule, one finds that for every pair, either they are identical, or that the label from the rule is “*”.

@see publicsuffix.org/list/

@example

PublicSuffix::Rule.factory("com").match?("example.com")
# => true
PublicSuffix::Rule.factory("com").match?("example.net")
# => false

@param name [String] the domain name to check @return [Boolean]

# File lib/public_suffix/rule.rb, line 163
def match?(name)
  # NOTE: it works because of the assumption there are no
  # rules like foo.*.com. If the assumption is incorrect,
  # we need to properly walk the input and skip parts according
  # to wildcard component.
  diff = name.chomp(value)
  diff.empty? || diff.end_with?(DOT)
end

parts ()

@abstract

# File lib/public_suffix/rule.rb, line 173
def parts
  raise NotImplementedError
end