* doc: some function/vars/const/package level updates
Various update that stood out while reading godoc.org for CoreDNS.
* Fix some misspellings as well
* Revert "pkg/typify: empty messages are OtherError (#1531)"
This reverts commit fc1d73ffa9.
* plugin/cache: add failsafeTTL
If we can not see what TTL we should put on a message to be cached, use
5 seconds as minimal TTL. We used to apply the maximum TTL to these
messages.
Messages with nothing in them are considered OtherError, they can not
serve any purpose for normal clients (i.e. dyn update or notifies might
have a use for them).
Also update a test in the cache plugin, so that we explicitaly test for
this case.
* plugin/forward: on demand healtchecking
Only start doing health checks when we encouner an error (any error).
This uses the new pluing/pkg/up package to abstract away the actual
checking. This reduces the LOC quite a bit; does need more testing, unit
testing and tcpdumping a bit.
* fix tests
* Fix readme
* Use pkg/up for healthchecks
* remove unused channel
* more cleanups
* update readme
* * Again do go generate and go build; still referencing the wrong forward
repo? Anyway fixed.
* Use pkg/up for doing the healtchecks to cut back on unwanted queries
* Change up.Func to return an error instead of a boolean.
* Drop the string target argument as it doesn't make sense.
* Add healthcheck test on failing to get an upstream answer.
TODO(miek): double check Forward and Lookup and how they interact with
HC, and if we correctly call close() on those
* actual test
* Tests here
* more tests
* try getting rid of host
* Get rid of the host indirection
* Finish removing hosts
* moar testing
* import fmt
* field is not used
* docs
* move some stuff
* bring back health_check
* maxfails=0 test
* git and merging, bah
* review
This adds a generic way of start a check function to check a backend.
This package can be used to kick off healthchecks. The package makes
sure only 1 is run at any one time.
It should allow for:
See upstream error -> kick off healthcheck
and not to worry about overwhelming the upstream with a barrage of
queries.
* add new policy always_first to mimic windows dns resolvers
fill documentation, add UT and cleanup fmt
* change name of policy from always_first to first. Update docs
HTTP healthchecking will be implicitely activated for proxy upstream
hosts, even if not configured. The README states that not using the
health_check directive will disable HTTP healthchecks though.
It seems to me that the availability of the HealthCheck.Path attribute
is used as indicator whether HTTP healthchecks should be used or not.
The normalizeCheckURL() function didn't check that attribute though,
always returning a CheckURL. This would increase the healthcheck failure
on every third failure in plugin/proxy, without any possibility for the
upstream host to be marked as healthy again. This would eventually
remove all upstream hosts from the serving pool.
* Add pkg/fall for Fallthrough
Move this into it's own package to facilitate tests. Important bug
was fixed: make the names fully qualified.
Add fall package to hosts, reverse, etcd, and fix kubernetes and any
tests. The k8s tests are still as-is, might need a future cleanup.
* dnstest: add multirecorder
This adds a new recorder that captures all messages written to it. This
can be useful when, for instance, testing AXFR which can write muliple
messages back to the client.
* docs
When we failing the healthcheck we should increate the fails for this
host; which is the *bleeping* point of doing the HC in the first place.
Add the missing atomic.Adds.
Fixes#1247
* core: allow all CIDR ranges in zone specifications
Allow (e.g.) a v4 reverse on a /17. If a zone is specified in such a
way a FilterFunc is set in the config. This filter is checked against
incoming queries.
For all other queries this adds a 'x != nil' check which will not impact
performace too much. Benchmark function is added as well to check for
this as wel.
Add multiple tests in tests/server_reverse_test.go.
Benchmark shows in the non-reverse case this hardly impact the speed:
~~~
classless:
pkg: github.com/coredns/coredns/core/dnsserver
BenchmarkCoreServeDNS-4 1000000 1431 ns/op 16 B/op 1 allocs/op
pkg: github.com/coredns/coredns/core/dnsserver
BenchmarkCoreServeDNS-4 1000000 1429 ns/op 16 B/op 1 allocs/op
master:
pkg: github.com/coredns/coredns/core/dnsserver
BenchmarkCoreServeDNS-4 1000000 1412 ns/op 16 B/op 1 allocs/op
pkg: github.com/coredns/coredns/core/dnsserver
BenchmarkCoreServeDNS-4 1000000 1429 ns/op 16 B/op 1 allocs/op
~~~
* README.md updates
* healthchecks: check on every 3rd failure
Check on every third failure and some cleanups to make this possible. A
failed healthcheck will never increase Fails, a successfull healthceck
will reset Fails to 0. This is a chance this counter now drops below 0,
making the upstream super? healthy.
This removes the okUntil smartness and condences everything back to 1
metrics: Fails; so it's simpler in that regard.
Timout errors are *not* attributed to the local upstream, and don't get
counted into the Fails anymore. Meaning the 'dig any isc.org' won't kill
your upstream.
Added extra test the see if the Fails counter gets reset after 3 failed
connection.
There is still a disconnect beween HTTP healthceck working the proxy (or
lookup) not being able to connect to the upstream.
* Fix tests
Fix file/fuzz.go build and docs in Makefile.fuzz
Each plugin can add a fuzz.go to join the fuzzing craze.
pkg/fuzz/do.go could be made a lot smarter, but is probably good enough
for starters.
$ make -f Makefile.fuzz <plugin>
will build with go-fuzz-build and then execute a go-fuzz run. Each
plugin's fuzz run uses a per-plugin directory to store the fuzz data.
* healhcheck: various cleanups
Network wasn't used. IgnorePaths wasn't used. Move checkdown function to
common function shared between proxy protocols. And some naming fixed.
Also reset the Fails on a succesful healthcheck back to 0.
remove newlines from log
* compile
* fix test
Add a full test server impl in this new package + tests. Move
dnsrecorder into this package as well and finish up the commented out
tests that were left in the old dnsrecorder package.
Update all callers and tests.
* 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
