It's time for another update on Ruby Whois library. Let's talk about name servers.
The most part of WHOIS servers follow the "convention" to include the name server list of a domain in the WHOIS record.
A name server is represented by a DNS name, which is a string.
ns1.google.com
ns2.google.com
The DNS name resolves to an IPv4 IP address.
ns1.google.com => 216.239.32.10
ns2.google.com => 216.239.34.10
Optionally, the DNS name can resolve to an IPv6 IP address.git
ns1.nic.fr => 2001:660:3003:2::4:1
ns2.nic.fr => 2001:660:3005:1::1:2
Each WHOIS server arbitrary choses the amount of information to store and return in a WHOIS record. Some registries returns only the DNS name, other registries include IP addresses as well.
In the current WHOIS version, the list of name servers is accessible through the #nameservers property.
r = Whois.query "google.com"
r.nameservers
# => ["ns1.google.com", "ns2.google.com"]
The method returns an Array of String. This is a lossy implementation because it completely ignores the IPv4 and IPv6 details.
The new Whois version solves this problem by introducing a new Whois::Answer::Nameserver object. This object is a Struct composed by three attributes: name, ipv4 and ipv6.
ns = Nameserver.new(
:name => "ns1.nic.fr",
:ipv4 => "192.134.4.1",
:ipv6 => "2001:660:3003:2::4:1"
)
ns.name
# => "ns1.nic.fr"
ns.ipv4
# => "192.134.4.1"
ns.ipv6
# => "2001:660:3003:2::4:1"
In the new Whois version, the #nameservers implementation has been changed to return an array of Nameserver instead of a simple String.
r = Whois.query "nic.fr"
r.nameservers
# => [
# #<struct Whois::Answer::Nameserver name="ns1.nic.fr", ipv4="192.134.4.1", ipv6="2001:660:3003:2::4:1">,
# #<struct Whois::Answer::Nameserver name="ns2.nic.fr", ipv4="192.93.0.4", ipv6="2001:660:3005:1::1:2">,
# ...
# ]
It's important to know that this change can break backwards compatibility. In order to minimize the impact, Nameserver#to_s returns the String value of the name attribute.
Nameserver.new(:name => "ns1.nic.fr", :ipv4 => "192.134.4.1").to_s
# => "ns1.nic.fr"