Add dns.edns.Option.to_generic()

[bwelling]

Converts an EDNS option represented by a custom class into an equivalent option represented by the generic option class. This is similar to the existing dns.rdata.Rdata.to_generic() method.

Also, adds a specialization to the existing dns.rdata.Rdata.to_generic() method for GenericRdata, to avoid extra work for applications that want to convert all rdata to generic form.

[chenrui333]

I have tested the patch in Homebrew/homebrew-core#193954, but still seeing the same issue

==> /opt/homebrew/Cellar/dnsviz/0.11.0/bin/dnsviz probe -d 0 -r example.com-probe-auth.json -o example.com.json
Traceback (most recent call last):
  File "/opt/homebrew/Cellar/dnsviz/0.11.0/bin/dnsviz", line 159, in <module>
    main()
    ~~~~^^
  File "/opt/homebrew/Cellar/dnsviz/0.11.0/bin/dnsviz", line 156, in main
    mod.main(args)
    ~~~~~~~~^^^^^^
  File "/opt/homebrew/Cellar/dnsviz/0.11.0/libexec/lib/python3.13/site-packages/dnsviz/commands/probe.py", line 1571, in main
    name_objs.append(OnlineDomainNameAnalysis.deserialize(name, arghelper.analysis_structured, cache))
                     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/homebrew/Cellar/dnsviz/0.11.0/libexec/lib/python3.13/site-packages/dnsviz/analysis/online.py", line 943, in deserialize
    a._deserialize_related(d)
    ~~~~~~~~~~~~~~~~~~~~~~^^^
  File "/opt/homebrew/Cellar/dnsviz/0.11.0/libexec/lib/python3.13/site-packages/dnsviz/analysis/online.py", line 1003, in _deserialize_related
    self.add_query(Q.DNSQuery.deserialize(query, bailiwick_map, default_bailiwick, cookie_jar_map, default_cookie_jar, cookie_standin, cookie_bad), detect_ns, detect_cookies)
    ~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/homebrew/Cellar/dnsviz/0.11.0/libexec/lib/python3.13/site-packages/dnsviz/analysis/online.py", line 524, in add_query
    self._process_response(query.responses[server][client], server, client, query, bailiwick, detect_ns, detect_cookies)
    ~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/homebrew/Cellar/dnsviz/0.11.0/libexec/lib/python3.13/site-packages/dnsviz/analysis/online.py", line 406, in _process_response
    self._set_server_cookies(response, server)
    ~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^
  File "/opt/homebrew/Cellar/dnsviz/0.11.0/libexec/lib/python3.13/site-packages/dnsviz/analysis/online.py", line 366, in _set_server_cookies
    server_cookie = response.get_server_cookie()
  File "/opt/homebrew/Cellar/dnsviz/0.11.0/libexec/lib/python3.13/site-packages/dnsviz/response.py", line 325, in get_server_cookie
    if cookie_opt is not None and len(cookie_opt.data) > 8:
                                      ^^^^^^^^^^^^^^^
AttributeError: 'CookieOption' object has no attribute 'data'

[rthalley]

This won't help dnsviz in the near term, this is to help avoid these issues in the future. Dnsviz will still have to do the workarounds Casey mentioned, or pin dnspython to 2.6.1.