Class: GitHubPages::HealthCheck::Domain

Inherits:
Checkable
  • Object
show all
Defined in:
lib/github-pages-health-check/domain.rb

Constant Summary collapse

LEGACY_IP_ADDRESSES = 
[
  # Legacy GitHub Datacenter
  "207.97.227.245",
  "204.232.175.78",

  # Aug. 2016 Fastly datacenter deprecation
  "199.27.73.133",
  "199.27.76.133",

  # Feb. 2017 Fastly datacenter deprecation
  "103.245.222.133",
  "103.245.223.133",
  "103.245.224.133",
  "104.156.81.133",
  "104.156.82.133",
  "104.156.83.133",
  "104.156.85.133",
  "104.156.87.133",
  "104.156.88.133",
  "104.156.89.133",
  "104.156.90.133",
  "104.156.91.133",
  "104.156.92.133",
  "104.156.93.133",
  "104.156.94.133",
  "104.156.95.133",
  "104.37.95.133",
  "157.52.64.133",
  "157.52.66.133",
  "157.52.67.133",
  "157.52.68.133",
  "157.52.69.133",
  "157.52.96.133",
  "172.111.64.133",
  "172.111.96.133",
  "185.31.16.133",
  "185.31.17.133",
  "185.31.18.133",
  "185.31.19.133",
  "199.27.74.133",
  "199.27.75.133",
  "199.27.76.133",
  "199.27.78.133",
  "199.27.79.133",
  "23.235.33.133",
  "23.235.37.133",
  "23.235.39.133",
  "23.235.40.133",
  "23.235.41.133",
  "23.235.43.133",
  "23.235.44.133",
  "23.235.45.133",
  "23.235.46.133",
  "23.235.47.133",
  "23.235.47.133",
  "43.249.72.133",
  "43.249.73.133",
  "43.249.74.133",
  "43.249.75.133",

  # 2018 Move to GitHub assigned IP space
  "192.30.252.153",
  "192.30.252.154"
].freeze
CURRENT_IP_ADDRESSES = 
%w(
  185.199.108.153
  185.199.109.153
  185.199.110.153
  185.199.111.153
).freeze
CURRENT_IPV6_ADDRESSES = 
%w(
  2606:50c0:8000::153
  2606:50c0:8001::153
  2606:50c0:8002::153
  2606:50c0:8003::153
).freeze
CURRENT_IP_ADDRESSES_ALL = 
(CURRENT_IP_ADDRESSES + CURRENT_IPV6_ADDRESSES).freeze
HASH_METHODS = 
%i[
  host uri nameservers dns_resolves? proxied? cloudflare_ip?
  fastly_ip? old_ip_address? a_record? aaaa_record? a_record_present? aaaa_record_present?
  cname_record? mx_records_present? valid_domain? apex_domain?
  should_be_a_record? cname_to_github_user_domain? cname_to_domain_to_pages?
  cname_to_pages_dot_github_dot_com? cname_to_fastly?
  pointed_to_github_pages_ip? non_github_pages_ip_present? pages_domain?
  served_by_pages? valid? reason valid_domain? https?
  enforces_https? https_error https_eligible? caa_error dns_zone_soa? dns_zone_ns?
].freeze
REQUESTED_RECORD_TYPES = 
[
  Dnsruby::Types::A,
  Dnsruby::Types::AAAA,
  Dnsruby::Types::CNAME,
  Dnsruby::Types::MX,
  Dnsruby::Types::NS,
  Dnsruby::Types::SOA
].freeze

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Methods inherited from Checkable

#reason, #to_hash, #to_json, #to_s, #to_s_pretty, #valid?

Constructor Details

#initialize(host, nameservers: :default) ⇒ Domain

Returns a new instance of Domain.



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# File 'lib/github-pages-health-check/domain.rb', line 105

def initialize(host, nameservers: :default)
  unless host.is_a? String
    raise ArgumentError, "Expected string, got #{host.class}"
  end

  @host = normalize_host(host)
  @nameservers = nameservers
  @resolver = GitHubPages::HealthCheck::Resolver.new(self.host,
                                                     :nameservers => nameservers)
end

Instance Attribute Details

#host ⇒ Object (readonly)

Returns the value of attribute host.



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# File 'lib/github-pages-health-check/domain.rb', line 6

def host
  @host
end

#nameservers ⇒ Object (readonly)

Returns the value of attribute nameservers.



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# File 'lib/github-pages-health-check/domain.rb', line 6

def nameservers
  @nameservers
end

#resolver ⇒ Object (readonly)

Returns the value of attribute resolver.



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# File 'lib/github-pages-health-check/domain.rb', line 6

def resolver
  @resolver
end

Class Method Details

.redundant(host) ⇒ Object 



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# File 'lib/github-pages-health-check/domain.rb', line 101

def self.redundant(host)
  GitHubPages::HealthCheck::RedundantCheck.new(host).check
end

Instance Method Details

#a_record? ⇒ Boolean

Is this domain’s first response an A record?

Returns:

  • (Boolean) 


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# File 'lib/github-pages-health-check/domain.rb', line 371

def a_record?
  return @is_a_record if defined?(@is_a_record)
  return unless dns?

  @is_a_record = Dnsruby::Types::A == dns.first.type
end

#a_record_present? ⇒ Boolean

Does this domain has an A record setup (not necessarily as the first record)?

Returns:

  • (Boolean) 


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# File 'lib/github-pages-health-check/domain.rb', line 387

def a_record_present?
  return unless dns?

  dns.any? { |answer| answer.type == Dnsruby::Types::A && answer.name.to_s == host }
end

#aaaa_record? ⇒ Boolean

Is this domain’s first response an AAAA record?

Returns:

  • (Boolean) 


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# File 'lib/github-pages-health-check/domain.rb', line 379

def aaaa_record?
  return @is_aaaa_record if defined?(@is_aaaa_record)
  return unless dns?

  @is_aaaa_record = Dnsruby::Types::AAAA == dns.first.type
end

#aaaa_record_present? ⇒ Boolean

Does this domain has an AAAA record setup (not necessarily as the first record)?

Returns:

  • (Boolean) 


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# File 'lib/github-pages-health-check/domain.rb', line 394

def aaaa_record_present?
  return unless dns?

  dns.any? { |answer| answer.type == Dnsruby::Types::AAAA && answer.name.to_s == host }
end

#apex_domain? ⇒ Boolean

Is this domain an apex domain, meaning a CNAME would be inappropriate

Returns:

  • (Boolean) 


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# File 'lib/github-pages-health-check/domain.rb', line 174

def apex_domain?
  return @apex_domain if defined?(@apex_domain)

  return false unless valid_domain?

  return true if dns_zone_soa? && dns_zone_ns?

  # PublicSuffix.domain pulls out the apex-level domain name.
  # E.g. PublicSuffix.domain("techblog.netflix.com") # => "netflix.com"
  # It's aware of multi-step top-level domain names:
  # E.g. PublicSuffix.domain("blog.digital.gov.uk") # => "digital.gov.uk"
  # For apex-level domain names, DNS providers do not support CNAME records.
  unicode_host = Addressable::IDNA.to_unicode(host)
  PublicSuffix.domain(unicode_host,
                      :default_rule => nil,
                      :ignore_private => true) == unicode_host
end

#caa_error ⇒ Object

Any errors querying CAA records



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# File 'lib/github-pages-health-check/domain.rb', line 486

def caa_error
  return nil unless caa&.errored?

  caa.error.class.name
end

#check! ⇒ Object

Runs all checks, raises an error if invalid rubocop:disable Metrics/AbcSize



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# File 'lib/github-pages-health-check/domain.rb', line 118

def check!
  raise Errors::InvalidDomainError.new :domain => self unless valid_domain?
  raise Errors::InvalidDNSError.new :domain => self    unless dns_resolves?
  raise Errors::DeprecatedIPError.new :domain => self  if deprecated_ip?
  return true if proxied?
  raise Errors::InvalidARecordError.new :domain => self    if invalid_a_record?
  raise Errors::InvalidCNAMEError.new :domain => self      if invalid_cname?
  raise Errors::InvalidAAAARecordError.new :domain => self if invalid_aaaa_record?
  raise Errors::NotServedByPagesError.new :domain => self  unless served_by_pages?

  true
end

#cloudflare_ip? ⇒ Boolean

Does the domain resolve to a CloudFlare-owned IP

Returns:

  • (Boolean) 


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# File 'lib/github-pages-health-check/domain.rb', line 299

def cloudflare_ip?
  cdn_ip?(CloudFlare)
end

#cname ⇒ Object

The domain to which this domain’s CNAME resolves Returns nil if the domain is not a CNAME



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# File 'lib/github-pages-health-check/domain.rb', line 411

def cname
  return unless dns?

  cnames = dns.take_while { |answer| answer.type == Dnsruby::Types::CNAME }
  return if cnames.empty?

  www_cname(cnames.last)
  @cname ||= Domain.new(cnames.last.cname.to_s)
end

#cname_record? ⇒ Boolean Also known as: cname?

Is this domain’s first response a CNAME record?

Returns:

  • (Boolean) 


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# File 'lib/github-pages-health-check/domain.rb', line 401

def cname_record?
  return unless dns?
  return false unless cname

  cname.valid_domain?
end

#cname_to_domain_to_pages? ⇒ Boolean

Check if the CNAME points to a Domain that points to pages e.g. CNAME -> Domain -> Pages rubocop:disable Metrics/AbcSize

Returns:

  • (Boolean) 


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# File 'lib/github-pages-health-check/domain.rb', line 249

def cname_to_domain_to_pages?
  return false unless dns?

  a_record_to_pages = dns.select { |d| d.type == Dnsruby::Types::A && d.name.to_s == host }.first

  return false unless a_record_to_pages && cname? && !cname_to_pages_dot_github_dot_com? && @www_cname

  CURRENT_IP_ADDRESSES.include?(a_record_to_pages.address.to_s.downcase)
end

#cname_to_fastly? ⇒ Boolean

Is the given domain CNAME’d directly to our Fastly account?

Returns:

  • (Boolean) 


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# File 'lib/github-pages-health-check/domain.rb', line 269

def cname_to_fastly?
  cname? && !pages_domain? && cname.fastly?
end

#cname_to_github_user_domain? ⇒ Boolean

Is the domain’s first response a CNAME to a pages domain?

Returns:

  • (Boolean) 


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# File 'lib/github-pages-health-check/domain.rb', line 242

def cname_to_github_user_domain?
  cname? && !cname_to_pages_dot_github_dot_com? && cname.pages_domain?
end

#cname_to_pages_dot_github_dot_com? ⇒ Boolean

Is the given domain a CNAME to pages.github.(io|com) instead of being CNAME’d to the user’s subdomain?

domain - the domain to check, generally the target of a cname

Returns:

  • (Boolean) 


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# File 'lib/github-pages-health-check/domain.rb', line 264

def cname_to_pages_dot_github_dot_com?
  cname? && cname.pages_dot_github_dot_com?
end

#deprecated_ip? ⇒ Boolean

rubocop:enable Metrics/AbcSize

Returns:

  • (Boolean) 


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# File 'lib/github-pages-health-check/domain.rb', line 132

def deprecated_ip?
  return @deprecated_ip if defined? @deprecated_ip

  @deprecated_ip = (valid_domain? && a_record? && old_ip_address?)
end

#dns ⇒ Object

Returns an array of DNS answers



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# File 'lib/github-pages-health-check/domain.rb', line 338

def dns
  return @dns if defined? @dns
  return unless valid_domain?

  @dns = Timeout.timeout(TIMEOUT) do
    GitHubPages::HealthCheck.without_warnings do
      next if host.nil?

      REQUESTED_RECORD_TYPES
        .map { |type| resolver.query(type) }
        .flatten.uniq
    end
  end
rescue StandardError
  @dns = nil
end

#dns? ⇒ Boolean Also known as: dns_resolves?

Are we even able to get the DNS record?

Returns:

  • (Boolean) 


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# File 'lib/github-pages-health-check/domain.rb', line 356

def dns?
  !(dns.nil? || dns.empty?)
end

#dns_zone_ns? ⇒ Boolean

Does the domain have associated NS records?

Returns:

  • (Boolean) 


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# File 'lib/github-pages-health-check/domain.rb', line 207

def dns_zone_ns?
  return @ns_records if defined?(@ns_records)
  return false unless dns?

  @ns_records = dns.any? do |answer|
    answer.type == Dnsruby::Types::NS && answer.name.to_s == host
  end
end

#dns_zone_soa? ⇒ Boolean

Does the domain have an associated SOA record?

Returns:

  • (Boolean) 


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# File 'lib/github-pages-health-check/domain.rb', line 195

def dns_zone_soa?
  return @soa_records if defined?(@soa_records)
  return false unless dns?

  @soa_records = dns.any? do |answer|
    answer.type == Dnsruby::Types::SOA && answer.name.to_s == host
  end
end

#enforces_https? ⇒ Boolean

Does this domain redirect HTTP requests to HTTPS?

Returns:

  • (Boolean) 


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# File 'lib/github-pages-health-check/domain.rb', line 463

def enforces_https?
  return false unless https? && http_response.headers["Location"]

  redirect = Addressable::URI.parse(http_response.headers["Location"])
  redirect.scheme == "https" && redirect.host == host
end

#fastly? ⇒ Boolean

Is the host our Fastly CNAME?

Returns:

  • (Boolean) 


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# File 'lib/github-pages-health-check/domain.rb', line 294

def fastly?
  !!host.match(/\A#{Regexp.union(Fastly::HOSTNAMES)}\z/i)
end

#fastly_ip? ⇒ Boolean

Does the domain resolve to a Fastly-owned IP

Returns:

  • (Boolean) 


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# File 'lib/github-pages-health-check/domain.rb', line 304

def fastly_ip?
  cdn_ip?(Fastly)
end

#github_domain? ⇒ Boolean

Is this domain owned by GitHub?

Returns:

  • (Boolean) 


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# File 'lib/github-pages-health-check/domain.rb', line 289

def github_domain?
  host.downcase.eql?("github.com") || host.downcase.end_with?(".github.com")
end

#https? ⇒ Boolean

Does this domain respond to HTTPS requests with a valid cert?

Returns:

  • (Boolean) 


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# File 'lib/github-pages-health-check/domain.rb', line 452

def https?
  https_response.return_code == :ok
end

#https_eligible? ⇒ Boolean

Can an HTTPS certificate be issued for this domain?

Returns:

  • (Boolean) 


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# File 'lib/github-pages-health-check/domain.rb', line 471

def https_eligible?
  # Can't have any IP's which aren't GitHub's present.
  return false if non_github_pages_ip_present?

  # Can't have underscores in the domain name (Let's Encrypt does not allow it)
  return false if host.include?("_")

  # Must be a CNAME or point to our IPs.
  return true if cname_to_github_user_domain? || cname_to_domain_to_pages?

  # Check CAA records for the full domain and its parent domain.
  pointed_to_github_pages_ip? && caa.lets_encrypt_allowed?
end

#https_error ⇒ Object

The response code of the HTTPS request, if it failed. Useful for diagnosing cert errors



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# File 'lib/github-pages-health-check/domain.rb', line 458

def https_error
  https_response.return_code unless https?
end

#invalid_a_record? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/github-pages-health-check/domain.rb', line 144

def invalid_a_record?
  return @invalid_a_record if defined? @invalid_a_record

  @invalid_a_record = (valid_domain? && a_record_present? && !should_be_a_record?)
end

#invalid_aaaa_record? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/github-pages-health-check/domain.rb', line 138

def invalid_aaaa_record?
  return @invalid_aaaa_record if defined? @invalid_aaaa_record

  @invalid_aaaa_record = (valid_domain? && aaaa_record_present? && !should_be_a_record?)
end

#invalid_cname? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/github-pages-health-check/domain.rb', line 150

def invalid_cname?
  return @invalid_cname if defined? @invalid_cname

  @invalid_cname = begin
    return false unless valid_domain?
    return false if github_domain? || apex_domain?
    return true  if cname_to_pages_dot_github_dot_com? || cname_to_fastly?

    !cname_to_github_user_domain? && should_be_cname_record?
  end
end

#mx_records_present? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/github-pages-health-check/domain.rb', line 427

def mx_records_present?
  return unless dns?

  dns.any? { |answer| answer.type == Dnsruby::Types::MX }
end

#non_github_pages_ip_present? ⇒ Boolean

Are any of the domain’s A or AAAA records pointing elsewhere?

Returns:

  • (Boolean) 


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# File 'lib/github-pages-health-check/domain.rb', line 233

def non_github_pages_ip_present?
  return unless dns?

  dns
    .select { |a| Dnsruby::Types::A == a.type || Dnsruby::Types::AAAA == a.type }
    .any? { |a| !github_pages_ip?(a.address.to_s) }
end

#old_ip_address? ⇒ Boolean

Does this domain have any A record that points to the legacy IPs?

Returns:

  • (Boolean) 


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# File 'lib/github-pages-health-check/domain.rb', line 362

def old_ip_address?
  return unless dns?

  dns.any? do |answer|
    answer.type == Dnsruby::Types::A && legacy_ip?(answer.address.to_s)
  end
end

#pages_domain? ⇒ Boolean

Is the host a *.github.(io|com) domain?

Returns:

  • (Boolean) 


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# File 'lib/github-pages-health-check/domain.rb', line 279

def pages_domain?
  !!host.match(/\A[\w-]+\.github\.(io|com)\.?\z/i)
end

#pages_dot_github_dot_com? ⇒ Boolean

Is the host pages.github.com or pages.github.io?

Returns:

  • (Boolean) 


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# File 'lib/github-pages-health-check/domain.rb', line 284

def pages_dot_github_dot_com?
  !!host.match(/\Apages\.github\.(io|com)\.?\z/i)
end

#pages_io_domain? ⇒ Boolean

Is the host a *.github.io domain?

Returns:

  • (Boolean) 


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# File 'lib/github-pages-health-check/domain.rb', line 274

def pages_io_domain?
  !!host.match(/\A[\w-]+\.github\.(io)\.?\z/i)
end

#pointed_to_github_pages_ip? ⇒ Boolean

Is the domain’s first response an A or AAAA record to a valid GitHub Pages IP?

Returns:

  • (Boolean) 


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# File 'lib/github-pages-health-check/domain.rb', line 226

def pointed_to_github_pages_ip?
  return false unless address_record?

  CURRENT_IP_ADDRESSES_ALL.include?(dns.first.address.to_s.downcase)
end

#proxied? ⇒ Boolean

Does this non-GitHub-pages domain proxy a GitHub Pages site?

This can be:

1. A Cloudflare-owned IP address
2. A site that returns GitHub.com server headers, but
   isn't CNAME'd to a GitHub domain
3. A site that returns GitHub.com server headers, but
   isn't CNAME'd to a GitHub IP

Returns:

  • (Boolean) 


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# File 'lib/github-pages-health-check/domain.rb', line 316

def proxied?
  return unless dns?
  return true if cloudflare_ip?
  return false if pointed_to_github_pages_ip?
  return false if cname_to_github_user_domain?
  return false if cname_to_domain_to_pages?
  return false if cname_to_pages_dot_github_dot_com?
  return false if cname_to_fastly? || fastly_ip?

  served_by_pages?
end

#served_by_pages? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/github-pages-health-check/domain.rb', line 433

def served_by_pages?
  return @served_by_pages if defined? @served_by_pages
  return unless dns_resolves?

  @served_by_pages = begin
    return true if response.headers["Server"] == "GitHub.com"

    # Typhoeus mangles the case of the header, compare insensitively
    response.headers.any? { |k, _v| k.downcase == "x-github-request-id" }
  end
end

#should_be_a_record? ⇒ Boolean

Should the domain use an A record?

Returns:

  • (Boolean) 


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# File 'lib/github-pages-health-check/domain.rb', line 217

def should_be_a_record?
  !pages_io_domain? && (apex_domain? || mx_records_present?)
end

#should_be_cname_record? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/github-pages-health-check/domain.rb', line 221

def should_be_cname_record?
  !should_be_a_record?
end

#uri(overrides = {}) ⇒ Object 



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# File 'lib/github-pages-health-check/domain.rb', line 445

def uri(overrides = {})
  options = { :host => host, :scheme => scheme, :path => "/" }
  options = options.merge(overrides)
  Addressable::URI.new(options).normalize.to_s
end

#valid_domain? ⇒ Boolean

Is this a valid domain that PublicSuffix recognizes? Used as an escape hatch to prevent false positives on DNS checks

Returns:

  • (Boolean) 


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# File 'lib/github-pages-health-check/domain.rb', line 164

def valid_domain?
  return @valid if defined? @valid

  unicode_host = Addressable::IDNA.to_unicode(host)
  @valid = PublicSuffix.valid?(unicode_host,
                               :default_rule => nil,
                               :ignore_private => true)
end

#www_cname(cname) ⇒ Object

Check if we have a ‘www.’ CNAME that matches the domain



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# File 'lib/github-pages-health-check/domain.rb', line 422

def www_cname(cname)
  @www_cname ||= cname.name.to_s.start_with?("www.") &&
    cname.name.to_s.end_with?(cname.domainname.to_s)
end