[Feature Request] Periodically log statistics

[maxmouchet]

Describe the feature requested

It would be useful to log statistics to stderr on some interval, similar to what zmap does:

0:02 25%; send: 1 done (444 p/s avg); recv: 0 0 p/s (0 p/s avg); drops: 0 p/s (0 p/s avg); hitrate: 0.00%

I sometimes use pv for this:

cat domains.txt | zdns A | pv -l > results.json

but this is not perfect:

• Requires an additional tool
• Additional CPU usage
• Only counts lines. No statistics on good/bad queries.
• Output designed for interactive terminal usage, not logs.

Some statistics that zdns could log:

• Queries per second
• Success rate
  • Breakdown by DNS code?
  • Breakdown by resolver?