Implement 'query-log'

[folbricht]

Implements #409

Adds a new query-log element that can log to file or STDOUT.

[groups.query-log]
type   = "query-log"
resolvers = ["cloudflare-dot"]
output-file = "/tmp/query.log" # Comment out to log to STDOUT

[cbuijs]

Could we add something so that the EDNS-ECS address is display in the log as well, or instead of the client-ip?

[folbricht]

Can certainly be done. To facilitate more values getting added, it's probably best to also switch to structured logging rather than using more columns.

[folbricht]

Added that, the output looks like this now:

time=2024-09-29T13:17:12.580+02:00 source-ip=127.0.0.1 question-name=google.com. question-class=IN question-type=A

Wondering if it'd be better to output these as JSON, or at least offer that as an option

[cbuijs]

Having plain-text and json as (both) options would be great. Tailing a json file is a bit tricky if you want to monitor (where I use it for).

[folbricht]

Added support for JSON output (optional). This produces JSONL which can be piped into jq .

[cbuijs]

I think this is fine to merge. No issues at all last months when using it all the time.