When CoreDNS starts up and can't get a zone transfer going the Apex is
empty. This `nil` is then transformed into wireformat, which fails with
a nil pointer dereference in Go DNS.

In this case we should just return SERVFAIL, because we don't have any
info (yet). Note the lookup code returned NXDOMAIN, which is correct
from a lookup standpoint, but also invalidates every name in the future
loaded zone.

Anyway, look for an apex before doing the lookup and return SERVFAIL if
nothing is found.

Fixes #679

Limit the options in both errors and log middleware, just output to
stdout and let someone else (journald,docker) care about where to route
the logs. This removes syslog and logging to a file.

Fixes #573 #602

* Add external service cnames

* remove cruft

* update CI k8s version

* change CI k8s version

* min k8s ver for ext services

* trying k8s 1.5

* k8s 1.5 requires ports spec

* remove kruft

* update dns schema version

* Update README.md

Minor cosmetic fixes, including one broken comment in a sample Corefile.

* Fix verb tense

* Test DNAME handling

If the DNAME itself matches the QTYPE, and the owner name matches QNAME,
the relevant DNAME RR should be included in the answer section.

Other parts of RFC 6672 are not implemented yet and hence left untested.

* Implement the DNAME substitution

As specified in RFC 6672, a DNAME substitution is performed by replacing
the suffix labels of the name being sought matching the owner name of
the DNAME resource record with the string of labels in the RDATA field.
The matching labels end with the root label in all cases. Only whole
labels are replaced.

* Handle DNAME redirection

A CNAME RR is created on-the-fly for the DNAME redirection. Be aware
that we do not have all the edge cases covered yet.

* Test DNAME owner name matching the QNAME

A DNAME RR redirects DNS names subordinate to its owner name; the owner
name of a DNAME is NOT redirected itself.

* Ignore names next to and below a DNAME record

According to RFC 6672, resource records MUST NOT exist at any subdomain
of the owner of a DNAME RR. When loading a zone, those names below the
DNAME RR will be quietly ignored.

* Streamline DNAME processing

Instead of checking DNAMEs during lookup, we use a preloaded list of
DNAME RRs to streamline the process without any runtime performance
penalty:

 * When loading the zone, keep a record of any DNAME RRs.
 * If there aren't any DNAMEs in the zone, just do the lookup as usual.
 * Only when the zone has one or more DNAME records, we look for the
   matching DNAME and ignore confronting subdomain(s) in the process.

* Make it easier to trace back through test errors

* Make DNAME handling part of lookup routine

DNAME processing is invoked only if the zone has at least one DNAME RR.

* Put DNAME resolution inside the searching of a hit

We can drop some of the other ideas; we don't need to track if we
have DNAMEs in the zone it just follows naturally from the current
lookup code.

See also: #664

This commit fixes some golint issues in `core/dnsserver`
and `middleware/kubernetes`.
Signed-off-by: Yong Tang <yong.tang.github@outlook.com>

Use @coredns.io were appropriate and clean up the list a little.

* commit for testing in cluster

* commit for testing in cluster

* refactor and add ns.dns record

* Release 007

* reduce heap allocations

* gofmt

* revert accidental Makefile commits

* restore prior rcode for disabled pod mode

* revert Makefile deltas

* add unit tests

* more unit tests

* make isRequestInReverseRange easier to test

* more unit tests

* addressing review feedback

* commit setup.go

* middleware/chaos: fix version

Move the version setting into a init function so it is done early. Then
tweak the setup code for chaos a bit to correctly pick this version up.
Add an integration test to pick this up in the toplevel test/ directory.

Fixes #667

* Update tests

Make the default target do nothing and put the actual release under a
'release' target. Prevent accidentally committing unwanted commits to
the repo.

Tested with `make -f Makefile.release -n`.

In CNCF, we are experimenting with FOSSA for license scanning on all of our projects.

https://app.fossa.io/reports/7d989803-8931-4221-a11f-330b7f333cdd

Latest refactoring fubar-ed Makefile.release. Fix the Linux build
target.

* middleware/file: correctly parse the stanza

Parsing the file stanza would give precedence to 'transfer' and ignore
other bits if it wasn't specified.

This change fixes the parsing. The actually external CNAME retrieval is
working fine (once the upstream is correctly parsed).

This wasn't caught in tests, because we lack a parsing test for this.

Fixes #657

* Add tests

Allows one to use `make -f Makefile.release build-arm` to just get an
Arm binary.

Check message for expired sig and don't cache those.

Aside: This hack of caching entire messages is probably something we
should stop doing at some point in the future and do this on a per RRset
basis.

Fixes #367 #635

Add vendor with `go dep`

This fix updates vendor with `go dep`
Signed-off-by: Yong Tang <yong.tang.github@outlook.com>

This fix adds vendor setup with `go dep`
Signed-off-by: Yong Tang <yong.tang.github@outlook.com>

* update readme

* Add slack

Also add the slack channel.

* middleware/proxy: Kill goroutines on stop

Ports caddy's https://github.com/mholt/caddy/commit/59bf71c2932c3b814a6a1211c492a1aa9f71d4a1

Excludes the proxy_test.go test part though.

Fixes #644

* Add tests

* Revert "middleware/proxy: Make Unhealthy a pointer (#615)"

This reverts commit acbf522c.

* middleware/proxy: add proper locking

This add the proper locking around `Unhealthy`.

* add listen addr option

* Add listen address option to pprof

* There is configuration

* code styling

This method parses the Host field in the service. It returns 1 or 3
things 1) it is a host 2) an IPv4 address or an 3) IPv6 address.
This simplifies some code a bit and allows for 1 way of parsing the Host
field.

This *only* parse the Host field, Mail and/or Text values should be
checked separately.

We reuse the dns.TypeXXX values for this as to not invent anything new.

Url was wrong

Print corresponding error message when TLS initialization fails.

Add a MAINTAINERS file. It's not generated and not as elaborate (i.e. no
focus areas) as the one prometheus uses. But it's a start.

Generated with `git shortlog -s -n`, everyone with more than 5 commits.

Docs are put in `Makefile.release`.

Fixes #566

* Add fallthrough support for Kubernetes

This enables registering other services in the same zone as
Kubernetes services. This also re-orders the middleware chain
so that Kubernetes comes before other types, in order to make
this work out-of-the-box.

* Remove extra line

* Implements tracing in the native gRPC server

* Undo some unnecessary changes

* Properly revert trace/setup.go this time

* Some very very basic tests

* Remove warning for non-Trace middleware