Add query with TCP feature

Fitblip commented 3 years ago

Hi there!

This PR does 3 main things:

Adds in a :tcp option for DNS.resolve and DNS.query, which fixes #24. It looks like this:

iex(1)> DNS.resolve("google.com", :a, {"127.0.0.1", 53}, :tcp)
{:ok, [{172, 217, 3, 78}]}
iex(2)> DNS.query("google.com", :a, {"127.0.0.1", 53}, :tcp)
%DNS.Record{
  anlist: [
    %DNS.Resource{
      bm: [],
...SNIP...

It reworks some of the connection logic, removing the import Socket.Datagram and calling UDP functions directly to better differentiate the send!/recv! functions now that there is TCP connections too. I also added 5 second timeouts to both TCP and UDP calls, which fixes #31 (and supersedes #35, which I'll be closing)
It adds a DNS.ResourceOpt module to the top of resource.ex, without it there the library is unable to be used due to a breaking change in #32. I submitted #34, but will also be closing it in lieu of this PR.

Minor things

Cleans up some function specs, adds some docs
Adds a test for TCP DNS queries that mirrors the UDP version.
Bumped version to 2.2.0 since this introduces a new feature 🚀
Updates travis config to run against more modern versions of elixir/otp

Fitblip commented 3 years ago

Hey @tungd, I think this is ready to go now if you don't mind reviewing!

tungd commented 3 years ago

Merged! Thanks a lot for contributing. A new release will be published to Hex soon. 🎉

Fitblip commented 3 years ago

Wonderful, thanks @tungd :). Thanks for the speedy merge and for such a great library!

tungd commented 3 years ago

@Fitblip version v2.2.0 has been released and is now available on Hex.

tungd / elixir-dns

Add query with TCP feature #36