* Rename middleware to plugin
first pass; mostly used 'sed', few spots where I manually changed
text.
This still builds a coredns binary.
* fmt error
* Rename AddMiddleware to AddPlugin
* Readd AddMiddleware to remain backwards compat
Adds a middleware to enable tracing with OpenTracing/OpenZipkin.
Enabling tracing will have a large impact on performance so it is
not advisable in production.
This checks if the next middleware to be called is nil, and if so returns
ServerFailure and an error. This makes the next calling more robust and
saves some lines of code.
Also prefix the error with the name of the middleware to aid in
debugging.
* 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
Add a new middleware that tells you who you are; IP, port and transport
is echoed back.
Also some various cleanup and documentation improvements while at it:
* ResponseWriter: improve the documentation of these helper functions.
* And add an NextHandler for use in tests. Make chaos_test.go and
* whoam_test.go use it.
Stop the caddy message and start our own init notifications.
Log the version of CoreDNS when starting up.
Fix all middleware's setup functions so that return the error prefixed
with *which* middleware was failing; leads to better debuggable errors
when starting up.
Add prometheus metrics to the cache handler. This just used prometheus,
if the metrics middleware does not setup the handler, there is nobody
reading these metrics, but they are still reported. Seems the simplest
solution while keeping the whole middleware separation in tact.
Make the CH middleware actually work. Needs a bit of a hack to route
the fake version.bind and friends zone to the correct handler. Fiddle
with the order in directive.go so that CH queries get logged as well.
Secondly add class rewriting to the rewrite middleware handler and also
log the class by default.
