Small tweak to tag docker image with current release number.

* add extra test

* middleware/auto: fix crash when calling empty handler

Don't call the next middleware, we should be auth. for this zone
getitng into this path we should respond with ServFail.

Fixes #388

Lint and vet the curret code add docs about adding a git post-commit
hook that performs these actions after each commit.

Don't panic on a non-existent directory. Add test for it as well.

Fixes #384

A NSEC record is need to deny any other name that might exist.
Also don't blindly perform the interface conversion when getting
glue for NS records as they now may include RRSIG - also add tests
for that.

Add a Reverse method to BackendService because different backends want
to to do diff. things. This allows etc/k8s to share even more code and
we can unify the PTR handling.

Fix the delegation handling in the *file* and *dnssec* middleware.
Refactor tests a bit and show that they are failling.

Add a Tree printer, cleanups and tests.
Fix wildcard test - should get no answer from empty-non-terminal

Disable this test (for now), it fails weirdly on travis
(and not locally). Initial suspicion that another server
is still reporting (or something). Anyway hard to replicate
locally - disable it for now.

* Fix k8s client to use client-go

* Fix Kubernetes Build Issue

The client-go code requires you to vendor. I have done a hack here
in the Makefile to vendor it to version 1.5. But looks like we
will need to do this the 'right' way soon.

* Convert v1 to api Objects in List Functions

Also removed the endpoint controller which was not used for anything.
The Watch functions may still need the same treatment.

* Vendor client-go release-1.5

* Fix basic SRV feature

This is actually not serving SRV records correctly, but this should
get it to work as it did prior to the k8s client changes. Another
fix will be needed to serve SRV records as defined in the spec.

* Add additional output in test result

Add the response to the test output.

* Fix erroneous test data

* Add metrics for cache hits/misses

Add counters for cache middleware hits and misses.

* Add test for cache middleware hit/miss counters.

* Fix cache hit metric incrementing.

* Add cache hit/miss metrics to dnssec middleware.

* Update README metric documentation.

* Add ServiceBackend interface

This adds a ServiceBackend interface that is shared between etcd/etcd3
(later) and kubernetes, leading to a massive reduction in code. When
returning the specific records from their backend.

Fixes #273

Fix the metrics test, top-level test directory still referenced the
old metrics name.

Cleanup names/typos to match standard naming conventions.

ListenAddr is the address where the prometheus metric are exported.
This can be used in tests to listen on "localhost:0" and then later
retrieve the metrics from there. It makes the tests indepent on each
other.

When a file is moved into position we should also reload the zones'
content.

This also fixes deadlock bug in the locking, a reload would block any
further lookups.

Add a separate request duration metrics specially for proxying requests
upstream.

Fixes #259

Add the rcode to the cached item and use this when we synthesize the
answer again. We could also infer the rcode from the reassembled
message, but this seems easier and is only an integer.

Also set the autoritative bit to 0 for all from-cache answers.

Fixes 357

This add a highlevel integration test for zone reloading. It also
fixes a data race in the actual reloading process.

- Implementing MX round-robin
- Slight tidy

* 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 option to parse resolv.conf for proxy upstreams

* Add test and README update for resolv.conf proxy

* Run gofmt

This fix uses docker container for kubectl. Since Kubernetes docker
image hyperkube has already been downloaded and it consists of
kubectl, there is really no need to download kubectl binary again.

This fix cleans up the Kubernetes related travis setup and removes
unneeded scripts.

This fix also fixes several mismatches of the Kubernetes version used,
so that any changes in version in the future only need to update .travis.yml.
Signed-off-by: Yong Tang <yong.tang.github@outlook.com>

The DS record is handled specially in the server ServeDNS mux, but there
was no code that actually called the correct middleware handler chain
when encountering a DS.

This PR fixes that behavoir, additonal bugs has been files to look into
how we are handling delegation (secure and non-secure ones).

This fix adds a `cache_capacity` option to dnssec middleware, so that
it is possible to specify the capacity of the LRU cache used by dnssec
middleware.
Signed-off-by: Yong Tang <yong.tang.github@outlook.com>

Add a test which enables caching and debug queries and make sure
the debug query does not overwrite the cache.

A small golint cleanup.
Signed-off-by: Yong Tang <yong.tang.github@outlook.com>

Add auto-load middleware that automatically picks up zones.

Every X seconds it will scan for new zones.
Add tests and documentation.

Make 'make test' use -race.

In the file middleware, if there are multiple zone files under a single root zone, watchers are only invoked on the last element of `zones.Names`. This is caused by loop override on the variable `n`.

This issue can be fixed by passing zone object, which calls reload watcher directly.

* Replace go-cache with golang-lru

This fix replace go-cache with golang-lru, as is specified in 335.
Signed-off-by: Yong Tang <yong.tang.github@outlook.com>

* Move cache initialization to setup

This commit move cache initialization to setup in dnssec middleware.
Signed-off-by: Yong Tang <yong.tang.github@outlook.com>