Add reverse_pointer filter and reverse_lookup lookup

[felixfontein]

SUMMARY

Add plugins for helping with reverse lookups:

1. A filter to convert IP addresses into DNS names for using with regular lookup plugins;
2. A reverse lookup plugin which does the whole thing in one step.

Fixes #227.

ISSUE TYPE

• New Module Pull Request

COMPONENT NAME

reverse_pointer filter

[github-actions]

Docs Build 📝

Thank you for contribution!✨

This PR has been merged and the docs are now incorporated into main:
https://ansible-collections.github.io/community.dns/branch/main

[oraNod]

LGTM. I suggested some type hints but I'll leave it to your discretion b/c I know they require import statements. I find them useful anyway. Hope this helps.

[oraNod]

Suggested change

	def reverse_pointer(ip):
	def reverse_pointer(ip: str) -> str:

[oraNod]

Suggested change

	def filters(self):
	def filters(self) -> Dict[str, Any]:

[felixfontein]

I'm not sure since when exactly, but since Python 3.8 or 3.9 you can also write dict[str, Any] (same for list and tuple etc.).

[oraNod]

Suggested change

	def run(self, terms, variables=None, **kwargs):
	def run(self, terms: List[str], variables: Optional[dict] = None, **kwargs: Any): -> List[str]:

[felixfontein]

Instead of Optional[dict] you can also use dict | None. That requires either 3.9 or 3.10 (I'm not sure anymore), but with the right __future__ import (I think from __future__ import annotations) you can already start using it in Python 3.7+ (as long as the type checking happens with a new enough Python).

[oraNod]

Suggested change

	def _resolve(resolver, name, rdtype, server_addresses):
	def _resolve(resolver, name: str, rdtype: int, server_addresses: Optional[List[str]]): -> List[str]:

[oraNod]

I think the type hint for the resolver parameter would be SimpleResolver right? so resolver: SimpleResolver

[felixfontein]

Type hints are a great idea; the collection requires ansible-core 2.14+, which means Python 3.9+ on the controller side. So type hints are definitely possible! (And already would have been since ansible-core 2.12+.)

I'd prefer to add type hints in a follow-up PR though (and then for everything else than modules and module_utils as well), and figure out there how well type checking works with ansible-test.

[felixfontein]

@oraNod thanks for reviewing this!