Class | Resolv::DNS |
In: |
lib/resolv.rb
|
Parent: | Object |
Resolv::DNS is a DNS stub resolver.
Information taken from the following places:
config_info can be:
nil: | Uses /etc/resolv.conf. |
String: | Path to a file using /etc/resolv.conf‘s format. |
Hash: | Must contain :nameserver, :search and :ndots keys. |
Example:
Resolv::DNS.new(:nameserver => ['210.251.121.21'], :search => ['ruby-lang.org'], :ndots => 1)
# File lib/resolv.rb, line 328 328: def initialize(config_info=nil) 329: @mutex = Mutex.new 330: @config = Config.new(config_info) 331: @initialized = nil 332: end
Creates a new DNS resolver. See Resolv::DNS.new for argument details.
Yields the created DNS resolver to the block, if given, otherwise returns it.
# File lib/resolv.rb, line 303 303: def self.open(*args) 304: dns = new(*args) 305: return dns unless block_given? 306: begin 307: yield dns 308: ensure 309: dns.close 310: end 311: end
Iterates over all IP addresses for name retrieved from the DNS resolver.
name can be a Resolv::DNS::Name or a String. Retrieved addresses will be a Resolv::IPv4 or Resolv::IPv6
# File lib/resolv.rb, line 385 385: def each_address(name) 386: each_resource(name, Resource::IN::A) {|resource| yield resource.address} 387: each_resource(name, Resource::IN::AAAA) {|resource| yield resource.address} 388: end
Iterates over all hostnames for address retrieved from the DNS resolver.
address must be a Resolv::IPv4, Resolv::IPv6 or a String. Retrieved names will be Resolv::DNS::Name instances.
# File lib/resolv.rb, line 420 420: def each_name(address) 421: case address 422: when Name 423: ptr = address 424: when IPv4::Regex 425: ptr = IPv4.create(address).to_name 426: when IPv6::Regex 427: ptr = IPv6.create(address).to_name 428: else 429: raise ResolvError.new("cannot interpret as address: #{address}") 430: end 431: each_resource(ptr, Resource::IN::PTR) {|resource| yield resource.name} 432: end
Iterates over all typeclass DNS resources for name. See getresource for argument details.
# File lib/resolv.rb, line 476 476: def each_resource(name, typeclass, &proc) 477: lazy_initialize 478: requester = make_requester 479: senders = {} 480: begin 481: @config.resolv(name) {|candidate, tout, nameserver| 482: msg = Message.new 483: msg.rd = 1 484: msg.add_question(candidate, typeclass) 485: unless sender = senders[[candidate, nameserver]] 486: sender = senders[[candidate, nameserver]] = 487: requester.sender(msg, candidate, nameserver) 488: end 489: reply, reply_name = requester.request(sender, tout) 490: case reply.rcode 491: when RCode::NoError 492: extract_resources(reply, reply_name, typeclass, &proc) 493: return 494: when RCode::NXDomain 495: raise Config::NXDomain.new(reply_name.to_s) 496: else 497: raise Config::OtherResolvError.new(reply_name.to_s) 498: end 499: } 500: ensure 501: requester.close 502: end 503: end
Gets the IP address of name from the DNS resolver.
name can be a Resolv::DNS::Name or a String. Retrieved address will be a Resolv::IPv4 or Resolv::IPv6
# File lib/resolv.rb, line 361 361: def getaddress(name) 362: each_address(name) {|address| return address} 363: raise ResolvError.new("DNS result has no information for #{name}") 364: end
Gets all IP addresses for name from the DNS resolver.
name can be a Resolv::DNS::Name or a String. Retrieved addresses will be a Resolv::IPv4 or Resolv::IPv6
# File lib/resolv.rb, line 372 372: def getaddresses(name) 373: ret = [] 374: each_address(name) {|address| ret << address} 375: return ret 376: end
Gets the hostname for address from the DNS resolver.
address must be a Resolv::IPv4, Resolv::IPv6 or a String. Retrieved name will be a Resolv::DNS::Name.
# File lib/resolv.rb, line 396 396: def getname(address) 397: each_name(address) {|name| return name} 398: raise ResolvError.new("DNS result has no information for #{address}") 399: end
Gets all hostnames for address from the DNS resolver.
address must be a Resolv::IPv4, Resolv::IPv6 or a String. Retrieved names will be Resolv::DNS::Name instances.
# File lib/resolv.rb, line 407 407: def getnames(address) 408: ret = [] 409: each_name(address) {|name| ret << name} 410: return ret 411: end
Look up the typeclass DNS resource of name.
name must be a Resolv::DNS::Name or a String.
typeclass should be one of the following:
Returned resource is represented as a Resolv::DNS::Resource instance, i.e. Resolv::DNS::Resource::IN::A.
# File lib/resolv.rb, line 457 457: def getresource(name, typeclass) 458: each_resource(name, typeclass) {|resource| return resource} 459: raise ResolvError.new("DNS result has no information for #{name}") 460: end
Looks up all typeclass DNS resources for name. See getresource for argument details.
# File lib/resolv.rb, line 466 466: def getresources(name, typeclass) 467: ret = [] 468: each_resource(name, typeclass) {|resource| ret << resource} 469: return ret 470: end