SRV record resolving would help me a lot with a project I work on. I'm not sure how hard it is to implement, since I don't really have any idea how dns works below the surface level. Will you get to it at some point in the future or would it be more promising for me to read into it and try to implement it myself?

Summary

• Durian.cr Domain Name System Resolver features has been very complete.
• However, the code of this repository is very messy and needs to be polished.
• This repository has been two years old, and the processing logic has undergone tremendous changes in some places.
• So, I think it is time to rework this repository.
• There may be breaking changes. (Updated: Feb 10, 2021)

In lib/durian/src/durian/extra/http/client.cr:26:15

26 | TCPSocket.connect hostname, @PORT, resolver, @connect_timeout
^------
Error: undefined method 'connect' for TCPSocket.class

crystal: 0.35.1

durian:
    git: https://github.com/636f7374/durian.cr.git
    version: 0.1.4

Using the demo code here:

https://paste.sr.ht/~z64/05e1209fea4e2d465b75e232720fba1ca72c96f8

Produces output:

$ cr _test.cr google.com 5
...................................................
  0 | 48.33ms
  1 | 48.34ms
  2 | 5024.24ms
  3 | 5024.25ms
  4 | 5024.25ms

because the domain is never removed from the pending list once it is resolved.

The following patch resolves this problem: https://git.sr.ht/~z64/durian.cr/commit/663ca66477d80c2ab8757d8f51669d6dd0e7e328

$ cr _test.cr google.com 5
.
  0 | 51.47ms
  1 | 51.48ms
  2 | 51.48ms
  3 | 51.48ms
  4 | 51.48ms

Please feel free to apply this patch or resolve at your discretion.

I have run into an issue attempting to use durian to resolve api.cognitive.microsoft.com. stdlib and other utilities can access and interact with this host fine, so it appears to be some issue with durian.. or perhaps I've misconfigured something?

I'm not that knowledgeable about DNS, so your help is appreciated.
I have example you can try here that fails: https://git.sr.ht/~z64/durian-issue-4/tree

Output is:

got std socket: #<TCPSocket:0x7fa845b91d10>
Unhandled exception: Invalid host address (Socket::Error)
  from lib/durian/src/durian/resolver.cr:223:17 in 'get_tcp_socket!'
  from src/durian-issue-4.cr:19:7 in '__crystal_main'
  from ../../../../../usr/lib/crystal/crystal/main.cr:105:5 in 'main_user_code'
  from ../../../../../usr/lib/crystal/crystal/main.cr:91:7 in 'main'
  from ../../../../../usr/lib/crystal/crystal/main.cr:114:3 in 'main'
  from __libc_start_main
  from _start
  from ???