Collect all DNS sections by calling to each_resource instead of each_answer #3886

wants to merge 2 commits into


None yet

3 participants


Disclaimer: same pull request on mruby impl (ruby/ruby#797), and bug open ( Not sure if I should report here a bug for the stdlib. For completeness:

A call to Message#each_answer does only include answers, however there are also two more kinds of
responses: Authority and Additional. Iterating through Message#each_resource allows us to retrieve
all information from the Message object.

This is specially important if, for example, we are trying to retrieve nameservers for a certain domain.

require 'resolv'
=> true
dns = => ['']) #
=> #<Resolv::DNS:0x3578436e ...>
puts dns.getresources('', Resolv::DNS::Resource::IN::NS).map(&:name)
=> nil

nil is returned. This, in a terminal fashion is equivalent to:

~ > dig ns
;; AUTHORITY SECTION:      86400   IN  NS      86400   IN  NS

There is indeed a response, but in the authority section, that is right now not collected by Resolv::DNS::getresource(s).

@ereslibre ereslibre Collect all DNS sections by calling to each_resource instead of each_…

When an authoritative server responds only on the authoritative section of the
DNS response, Resolv::DNS::getresource(s) interprets an empty response.
headius commented May 12, 2016

@ereslibre Wow, thanks for the footwork on this one!

Our stdlib is a lightly-patched duplicate of MRI's, but we generally don't patch stdlib unilaterally, so we'll wait to see if MRI accepts this. When that happens, ping again and we'll be happy to merge this into JRuby.

One minor nit: there's unrelated whitespace changes in here. Can you eliminate those?


@headius Amazing timing. Of course, I will get rid of those space changes, sorry ! Thanks for your wonderful work !

@ereslibre ereslibre Remove whitespace changes
headius commented May 19, 2016

@ereslibre I pinged the MRI issue to see if we can get some movement.

@headius headius added this to the JRuby milestone May 19, 2016

Thank you @headius ❤️

@enebo enebo modified the milestone: JRuby, JRuby May 25, 2016
headius commented Aug 24, 2016

Doesn't look like MRI's going to get back to us in time for If they don't respond for and we're still happy with this change, we'll just merge it.

@headius headius modified the milestone: JRuby, JRuby Aug 24, 2016

Thank you again @headius.

@headius headius added a commit that referenced this pull request Nov 8, 2016
@headius headius Incorporate MRI's fix for #3886. 9187c5e
headius commented Nov 8, 2016

MRI finally merged your fix! I've gone with their patch (yours sans whitespace changes) in 9187c5e.

@headius headius closed this Nov 8, 2016
@headius headius added a commit to jruby/ruby that referenced this pull request Nov 8, 2016
@headius headius Incorporate MRI fix for jruby/jruby#3886. 89a7b94
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment