return an error for multiple use of some plugins (#1559)

* plugins: Return error for multiple use of some

Return plugin.ErrOnce when a plugin that doesn't support it, is called
mutliple times.

This now adds it for: cache, dnssec, errors, forward, hosts, nsid.
And changes it slightly in kubernetes, pprof, reload, root.

* more tests
This commit is contained in:
Miek Gieben 2018-02-28 18:16:05 -08:00 committed by GitHub
parent 5faa9e7bc1
commit f697b33283
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
27 changed files with 150 additions and 95 deletions

View file

@ -104,3 +104,6 @@ const Namespace = "coredns"
// TimeBuckets is based on Prometheus client_golang prometheus.DefBuckets
var TimeBuckets = prometheus.ExponentialBuckets(0.00025, 2, 16) // from 0.25ms to 8 seconds
// ErrOnce is returned when a plugin doesn't support multiple setups per server.
var ErrOnce = errors.New("this plugin can only be used once per Server Block")