When a query, different from a TXT lookup is performed, all services
with a missing `Host` field should be filtered out, as these otherwize
cause a line in the answer section with a single dot (`.`) as the
result. This behavior manifests for example when a TXT record is present
on a domain, eg. an A or SRV lookup is performed on said domain.
If there are no services containing a `Host` field, a `NODATA` response
should be given. If there are other Services, these alone should be
returned for the query.
Filter any service that has an empty Host field from all lookup types
other than TXT to solve this issue. At the same time the check for empty
`Text` fields in TXT queries are also moved to the same check in the
etcd ServiceBackend.
This PR is a small golint fix:
```
coredns/plugin/test/helpers.go
Line 283: warning: redundant if ...; err != nil check, just return error instead. (golint)
```
Signed-off-by: Yong Tang <yong.tang.github@outlook.com>
There are string ttls at commands at README.md.
But because `TTL` of `Service` is uint32, commands at README is wrong.
e.g.) `etcdctl put /skydns/local/skydns/x1 '{"host":"1.1.1.1","ttl":"60"}'`.
The `b` struct is just copying all the fields into a new one, to
check if it already existed in a set. This isn't needed as all the
fields are identical, and a small rearrangement of the code solves the
same problem without the copy.
* Stop importing testing in the main binary
Stop importing "testing" into the main binary:
* test/helpers.go imported it; remote that and change function signature
* update all tests that use this
Signed-off-by: Miek Gieben <miek@miek.nl>
* Drop import testing from metrics plugin
Signed-off-by: Miek Gieben <miek@miek.nl>
* more fiddling
Signed-off-by: Miek Gieben <miek@miek.nl>
This fix deprecates endpoints for out-of-cluster k8s api,
The Corefile still takes multiple endpoints though only
the first one is used. A warning is shown if there are
multiple endpoints.
Signed-off-by: Yong Tang <yong.tang.github@outlook.com>
* Default to upstream to self
This is a backwards incompatible change.
This is a massive (cleanup) PR where we default to resolving external
names by the coredns process itself, instead of directly forwarding them
to some upstream.
This ignores any arguments `upstream` may have had and makes it depend
on proxy/forward configuration in the Corefile. This allows resolved
upstream names to be cached and we have better healthchecking of the
upstreams. It also means there is only one way to resolve names, by
either using the proxy or forward plugin.
The proxy/forward lookup.go functions have been removed. This also
lessen the dependency on proxy, meaning deprecating proxy will become
easier. Some tests have been removed as well, or moved to the top-level
test directory as they now require a full coredns process instead of
just the plugin.
For the etcd plugin, the entire StubZone resolving is *dropped*! This
was a hacky (but working) solution to say the least. If someone cares
deeply it can be brought back (maybe)?
The pkg/upstream is now very small and almost does nothing. Also the
New() function was changed to return a pointer to upstream.Upstream. It
also returns only one parameter, so any stragglers using it will
encounter a compile error.
All documentation has been adapted. This affected the following plugins:
* etcd
* file
* auto
* secondary
* federation
* template
* route53
A followup PR will make any upstream directives with arguments an error,
right now they are ignored.
Signed-off-by: Miek Gieben <miek@miek.nl>
* Fix etcd build - probably still fails unit test
Signed-off-by: Miek Gieben <miek@miek.nl>
* Slightly smarter lookup check in upstream
Signed-off-by: Miek Gieben <miek@miek.nl>
* Compilez
Signed-off-by: Miek Gieben <miek@miek.nl>
This fix will error out when multiple https endpoints are specified,
as additional work is needed to support beyond http.
This fix fixes 1464.
Signed-off-by: Yong Tang <yong.tang.github@outlook.com>
Almost 100% mechanical change, except the fact that import/import.md
is moved to import/README.md
No content changes.
Signed-off-by: Miek Gieben <miek@miek.nl>
* wip: add import to make it have docs
Fake the import plugin further to give it proper docs. This should help
make it more discoverable.
Signed-off-by: Miek Gieben <miek@miek.nl>
* Finish writing the documentation
Signed-off-by: Miek Gieben <miek@miek.nl>
Add words in object.go on the memory use and put some future ideas in
there to use even less (if we have to at some point).
Signed-off-by: Miek Gieben <miek@miek.nl>
* plugin/log: update nodata/NXDOMAIN story a bit
Add more words on nodata and NXDOMAIN which is a confusing DNS
"feature"
Fixes: #2412
Signed-off-by: Miek Gieben <miek@miek.nl>
* typos
Signed-off-by: Miek Gieben <miek@miek.nl>
Show from and to address when detecting a loop they may aid in
debugging.
Hard to create a unit test, but this is a startup run with self induced
loop:
~~~ corefile
.:1053 {
loop
log
forward . 127.0.0.1:1053
}
~~~~
~~~
:1053
2018-12-16T10:11:03.695Z [INFO] CoreDNS-1.3.0
2018-12-16T10:11:03.695Z [INFO] linux/amd64, go1.11,
CoreDNS-1.3.0
linux/amd64, go1.11,
2018-12-16T10:11:03.696Z [FATAL] plugin/loop: Loop (127.0.0.1:51384 -> :1053) detected for zone ".", see https://coredns.io/plugins/loop#troubleshooting. Query: "HINFO 2781022615773629442.4133547885299871809."
~~~
Update the docs and polished that a bit as well.
Signed-off-by: Miek Gieben <miek@miek.nl>
* Add new plugin: external
This plugin works in conjunction with the kubernetes plugin and exports
ingress and LB addresses as DNS records. It bypasses backend.go and
backend_lookup.go flow because it is not needed.
README, tests are implemented. The tests only exercise the unit tests,
this has not been tested in any ci.
Signed-off-by: Miek Gieben <miek@miek.nl>
* Rename to k8s_external
Signed-off-by: Miek Gieben <miek@miek.nl>
* go gen
Signed-off-by: Miek Gieben <miek@miek.nl>
The miekg/dns API is a bit scruffy (documentation PR in flight soon),
but these both need to be set for the correct RCODE to be reflected in
the returned packet.
Signed-off-by: Miek Gieben <miek@miek.nl>
This clear out the remaining map[x]bool usage and moves the bool to an
empty struct.
Two note worthy other changes:
* EnableChaos in the server is now also exported to make it show up in
the documentation.
* The auto plugin is left as is, because there the boolean is
explicitaly set to false to signal 'to-be-deleted' and the key is left
as-is.
Signed-off-by: Miek Gieben <miek@miek.nl>
* plugin/kubernetes: smaller map
to continue with a theme: the map[string]bool can be reduced
to map[string]struct{} to reduce a tiny amount of memory.
Signed-off-by: Miek Gieben <miek@miek.nl>
* fix tests
Signed-off-by: Miek Gieben <miek@miek.nl>
This is a relic from the etcd integration and only used to remove in the
final answer returned to the client. We do need it. Make it a constant
and only one character wide.
Signed-off-by: Miek Gieben <miek@miek.nl>
These maps where all map[x]bool. Change this a map[x]struct{} as this
is smaller and we only use these map to signal "this element exists".
This should preserve a (small) amount of memory.
Signed-off-by: Miek Gieben <miek@miek.nl>
Make the NewSRV and friends slightly smarter. Optimize the calling of
targetStrip which is almost certainly not used.
Added benchmark show a modest improvement:
benchmark old ns/op new ns/op delta
BenchmarkNewSRV-4 300 283 -5.67%
Signed-off-by: Miek Gieben <miek@miek.nl>
* Fix EDNS0 compliance
Do SizeAndDo in the server (ScrubWriter) and remove all uses of this
from the plugins. Also *always* do it. This is to get into compliance
for https://dnsflagday.net/.
The pkg/edns0 now exports the EDNS0 options we understand; this is
exported to allow plugins add things there. The *rewrite* plugin used
this to add custom EDNS0 option codes that the server needs to
understand.
This also needs a new release of miekg/dns because it triggered a
race-condition that was basicly there forever.
See:
* https://github.com/miekg/dns/issues/857
* https://github.com/miekg/dns/pull/859
Running a test instance and pointing the https://ednscomp.isc.org/ednscomp
to it shows the tests are now fixed:
~~~
EDNS Compliance Tester
Checking: 'miek.nl' as at 2018-12-01T17:53:15Z
miek.nl. @147.75.204.203 (drone.coredns.io.): dns=ok edns=ok edns1=ok edns@512=ok ednsopt=ok edns1opt=ok do=ok ednsflags=ok docookie=ok edns512tcp=ok optlist=ok
miek.nl. @2604:1380:2002:a000::1 (drone.coredns.io.): dns=ok edns=ok edns1=ok edns@512=ok ednsopt=ok edns1opt=ok do=ok ednsflags=ok docookie=ok edns512tcp=ok optlist=ok
All Ok
Codes
ok - test passed.
~~~
Signed-off-by: Miek Gieben <miek@miek.nl>
Signed-off-by: Miek Gieben <miek@miek.nl>
* typos in comments
Signed-off-by: Miek Gieben <miek@miek.nl>
I think this is causing problem and it will actually clash with the
scrubbing that now happens for all plugins anyway. We're assuming the
returned message will be valid even with tc being set. request.Scrub
follows that same logic.
Signed-off-by: Miek Gieben <miek@miek.nl>
* pkg/up: implement backoff
Every 2nd failure we double the interval until we hit 4 * interval. This
to have some sort of backoff, esp when a large cluster of coredns shares
an upstream (original intent of up package) they will hammer the
upstream. This put some back pressure on that.
Signed-off-by: Miek Gieben <miek@miek.nl>
* Update plugin/pkg/up/up.go
Co-Authored-By: miekg <miek@miek.nl>
Upgrade to new dns lib version; that saw multiple improvements; some
patch releases are in the pipeline.
The big thing here is the removal of ErrTruncated, so we need to deal
with this slightly different in the forward plugin. It removed the
entire truncated.go logic and just checks the message for .Truncated (if
there is a message) and retries with tcp.
Signed-off-by: Miek Gieben <miek@miek.nl>
