There was no inherent reason *not* to allow multiple listeners for the
monitoring data. Actually enforcing only one listener lead to more code
then just allowing multiple. It's probably not what you want; but
CoreDNS is happy to oblige.
* middleware/metrics: survive restart
Keep the handler running during restart. Stopping and starting the
handler results in "address in use" - sometimes, meaning the reload
will be flaky. In turn this behavior means any changes to the monitor
stanza are not picked up.
* remove resync
* middleware/metrics: add more metrics
middleware/cache:
Add metrics for number of elements in the cache. Also export the total
size. Update README to detail the new metrics.
middleware/metrics
Move metrics into subpackage called "vars". This breaks the import
cycle and is cleaner. This allows vars.Report to be used in the
the dnsserver to log refused queries.
middleware/metrics: tests
Add tests to the metrics framework. The metrics/test subpackage allows
scraping of the local server. Do a few test scrape of the metrics that
are defined in the metrics middleware.
This also allows metrics integration tests to check if the caching and
dnssec middleware export their metrics correctly.
* update README
* typos
* fix tests
This still needs cleanup, but this is a first pass the cleans some
cruft and documents our style (in middleware.md) and makes all the
docs match that style.
* Split response size into normal responses and AXFR|IXFR responses.
* Split out incoming sizes as well in normal and AXFR|IXFRs.
* Add meta qtype to the monitored qtypes.
* Make duration to be exported in milliseconds instead of seconds.
