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"
].freeze
NEW_PRIMARY_IPS =
%w(
  185.199.108.153
  185.199.109.153
  185.199.110.153
  185.199.111.153
).freeze
CURRENT_IP_ADDRESSES =
[
  "192.30.252.153",
  "192.30.252.154",
  *NEW_PRIMARY_IPS
].freeze
HASH_METHODS =
%i[
  host uri dns_resolves? proxied? cloudflare_ip? fastly_ip?
  old_ip_address? a_record? cname_record? mx_records_present?
  valid_domain? apex_domain? should_be_a_record?
  cname_to_github_user_domain? cname_to_pages_dot_github_dot_com?
  cname_to_fastly? pointed_to_github_pages_ip? pages_domain?
  served_by_pages? valid_domain? https? enforces_https? https_error
  https_eligible? caa_error
].freeze
REQUESTED_RECORD_TYPES =
[
  Dnsruby::Types::A,
  Dnsruby::Types::CNAME,
  Dnsruby::Types::MX
].freeze

Instance Attribute 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) ⇒ Domain

Returns a new instance of Domain.



92
93
94
95
96
97
98
# File 'lib/github-pages-health-check/domain.rb', line 92

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

  @host = normalize_host(host)
end

Instance Attribute Details

#hostObject (readonly)

Returns the value of attribute host.



6
7
8
# File 'lib/github-pages-health-check/domain.rb', line 6

def host
  @host
end

Instance Method Details

#a_record?Boolean

Is this domain’s first response an A record?

Returns:

  • (Boolean)


282
283
284
285
# File 'lib/github-pages-health-check/domain.rb', line 282

def a_record?
  return unless dns?
  dns.first.type == Dnsruby::Types::A
end

#apex_domain?Boolean

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

Returns:

  • (Boolean)


140
141
142
143
144
145
146
147
148
149
150
# File 'lib/github-pages-health-check/domain.rb', line 140

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

  # 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.
  PublicSuffix.domain(host) == host
end

#caa_errorObject

Any errors querying CAA records



351
352
353
354
# File 'lib/github-pages-health-check/domain.rb', line 351

def caa_error
  return nil unless caa.errored?
  caa.error.class.name
end

#check!Object

Runs all checks, raises an error if invalid



101
102
103
104
105
106
107
108
109
110
# File 'lib/github-pages-health-check/domain.rb', line 101

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

#cloudflare_ip?Boolean

Does the domain resolve to a CloudFlare-owned IP

Returns:

  • (Boolean)


210
211
212
# File 'lib/github-pages-health-check/domain.rb', line 210

def cloudflare_ip?
  cdn_ip?(CloudFlare)
end

#cnameObject

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



297
298
299
300
# File 'lib/github-pages-health-check/domain.rb', line 297

def cname
  return unless dns.first.type == Dnsruby::Types::CNAME
  @cname ||= Domain.new(dns.first.cname.to_s)
end

#cname_record?Boolean Also known as: cname?

Is this domain’s first response a CNAME record?

Returns:

  • (Boolean)


288
289
290
291
292
# File 'lib/github-pages-health-check/domain.rb', line 288

def cname_record?
  return unless dns?
  return false unless cname
  cname.valid_domain?
end

#cname_to_fastly?Boolean

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

Returns:

  • (Boolean)


185
186
187
# File 'lib/github-pages-health-check/domain.rb', line 185

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)


172
173
174
# File 'lib/github-pages-health-check/domain.rb', line 172

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, generaly the target of a cname

Returns:

  • (Boolean)


180
181
182
# File 'lib/github-pages-health-check/domain.rb', line 180

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

#deprecated_ip?Boolean

Returns:

  • (Boolean)


112
113
114
115
# File 'lib/github-pages-health-check/domain.rb', line 112

def deprecated_ip?
  return @deprecated_ip if defined? @deprecated_ip
  @deprecated_ip = (valid_domain? && a_record? && old_ip_address?)
end

#dnsObject

Returns an array of DNS answers



244
245
246
247
248
249
250
251
252
253
254
255
256
257
# File 'lib/github-pages-health-check/domain.rb', line 244

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(absolute_domain, type).answer }
        .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)


267
268
269
# File 'lib/github-pages-health-check/domain.rb', line 267

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

#enforces_https?Boolean

Does this domain redirect HTTP requests to HTTPS?

Returns:

  • (Boolean)


338
339
340
341
342
# File 'lib/github-pages-health-check/domain.rb', line 338

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)


205
206
207
# File 'lib/github-pages-health-check/domain.rb', line 205

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)


215
216
217
# File 'lib/github-pages-health-check/domain.rb', line 215

def fastly_ip?
  cdn_ip?(Fastly)
end

#github_domain?Boolean

Is this domain owned by GitHub?

Returns:

  • (Boolean)


200
201
202
# File 'lib/github-pages-health-check/domain.rb', line 200

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

#https?Boolean

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

Returns:

  • (Boolean)


327
328
329
# File 'lib/github-pages-health-check/domain.rb', line 327

def https?
  https_response.return_code == :ok
end

#https_eligible?Boolean

Can an HTTPS certificate be issued for this domain?

Returns:

  • (Boolean)


345
346
347
348
# File 'lib/github-pages-health-check/domain.rb', line 345

def https_eligible?
  (cname_to_github_user_domain? || pointed_to_new_primary_ips?) &&
    caa.lets_encrypt_allowed?
end

#https_errorObject

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



333
334
335
# File 'lib/github-pages-health-check/domain.rb', line 333

def https_error
  https_response.return_code unless https?
end

#invalid_a_record?Boolean

Returns:

  • (Boolean)


117
118
119
120
# File 'lib/github-pages-health-check/domain.rb', line 117

def invalid_a_record?
  return @invalid_a_record if defined? @invalid_a_record
  @invalid_a_record = (valid_domain? && a_record? && !should_be_a_record?)
end

#invalid_cname?Boolean

Returns:

  • (Boolean)


122
123
124
125
126
127
128
129
130
# File 'lib/github-pages-health-check/domain.rb', line 122

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)


302
303
304
305
# File 'lib/github-pages-health-check/domain.rb', line 302

def mx_records_present?
  return unless dns?
  dns.any? { |answer| answer.type == Dnsruby::Types::MX }
end

#old_ip_address?Boolean

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

Returns:

  • (Boolean)


273
274
275
276
277
278
279
# File 'lib/github-pages-health-check/domain.rb', line 273

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 domain?

Returns:

  • (Boolean)


190
191
192
# File 'lib/github-pages-health-check/domain.rb', line 190

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)


195
196
197
# File 'lib/github-pages-health-check/domain.rb', line 195

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

#pointed_to_github_pages_ip?Boolean

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

Returns:

  • (Boolean)


162
163
164
# File 'lib/github-pages-health-check/domain.rb', line 162

def pointed_to_github_pages_ip?
  a_record? && CURRENT_IP_ADDRESSES.include?(dns.first.address.to_s)
end

#pointed_to_new_primary_ips?Boolean

Is the domain’s first response an A record to the new primary IPs?

Returns:

  • (Boolean)


167
168
169
# File 'lib/github-pages-health-check/domain.rb', line 167

def pointed_to_new_primary_ips?
  a_record? && NEW_PRIMARY_IPS.include?(dns.first.address.to_s)
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)


227
228
229
230
231
232
233
234
235
# File 'lib/github-pages-health-check/domain.rb', line 227

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_pages_dot_github_dot_com?
  return false if cname_to_fastly? || fastly_ip?
  served_by_pages?
end

#resolverObject



259
260
261
262
263
264
# File 'lib/github-pages-health-check/domain.rb', line 259

def resolver
  @resolver ||= Dnsruby::Resolver.new
  @resolver.retry_times = 2
  @resolver.query_timeout = 2
  @resolver
end

#served_by_pages?Boolean

Returns:

  • (Boolean)


307
308
309
310
311
312
313
314
315
316
317
318
# File 'lib/github-pages-health-check/domain.rb', line 307

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

  @served_by_pages = begin
    return false unless response.mock? || response.return_code == :ok
    return true if response.headers["Server"] == "GitHub.com"

    # Typhoeus mangles the case of the header, compare insensitively
    response.headers.any? { |k, _v| k =~ /X-GitHub-Request-Id/i }
  end
end

#should_be_a_record?Boolean

Should the domain be an apex record?

Returns:

  • (Boolean)


153
154
155
# File 'lib/github-pages-health-check/domain.rb', line 153

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

#should_be_cname_record?Boolean

Returns:

  • (Boolean)


157
158
159
# File 'lib/github-pages-health-check/domain.rb', line 157

def should_be_cname_record?
  !should_be_a_record?
end

#uri(overrides = {}) ⇒ Object



320
321
322
323
324
# File 'lib/github-pages-health-check/domain.rb', line 320

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 checkes

Returns:

  • (Boolean)


134
135
136
137
# File 'lib/github-pages-health-check/domain.rb', line 134

def valid_domain?
  return @valid if defined? @valid
  @valid = PublicSuffix.valid?(host, :default_rule => nil)
end