diff options
Diffstat (limited to 'plugin')
| -rw-r--r-- | plugin/metrics/context.go | 24 | ||||
| -rw-r--r-- | plugin/metrics/metrics.go | 1 | ||||
| -rw-r--r-- | plugin/plugin.go | 6 |
3 files changed, 29 insertions, 2 deletions
diff --git a/plugin/metrics/context.go b/plugin/metrics/context.go new file mode 100644 index 000000000..4cce871f5 --- /dev/null +++ b/plugin/metrics/context.go @@ -0,0 +1,24 @@ +package metrics + +import ( + "github.com/coredns/coredns/plugin" + + "golang.org/x/net/context" +) + +// WithServer returns the current server handling the request. It returns the +// server listening address: <scheme>://[<bind>]:<port> Normally this is +// something like "dns://:53", but if the bind plugin is used, i.e. "bind +// 127.0.0.53", it will be "dns://127.0.0.53:53", etc. If not address is found +// the empty string is returned. +// +// Basic usage with a metric: +// +// <metric>.WithLabelValues(metrics.WithServer(ctx), labels..).Add(1) +func WithServer(ctx context.Context) string { + srv := ctx.Value(plugin.ServerCtx{}) + if srv == nil { + return "" + } + return srv.(string) +} diff --git a/plugin/metrics/metrics.go b/plugin/metrics/metrics.go index a49984b3d..e16749fc0 100644 --- a/plugin/metrics/metrics.go +++ b/plugin/metrics/metrics.go @@ -12,6 +12,7 @@ import ( "github.com/coredns/coredns/coremain" "github.com/coredns/coredns/plugin" "github.com/coredns/coredns/plugin/metrics/vars" + "github.com/prometheus/client_golang/prometheus" "github.com/prometheus/client_golang/prometheus/promhttp" ) diff --git a/plugin/plugin.go b/plugin/plugin.go index 2510dbaa6..b3d5cc6ab 100644 --- a/plugin/plugin.go +++ b/plugin/plugin.go @@ -68,8 +68,7 @@ func (f HandlerFunc) Name() string { return "handlerfunc" } // Error returns err with 'plugin/name: ' prefixed to it. func Error(name string, err error) error { return fmt.Errorf("%s/%s: %s", "plugin", name, err) } -// NextOrFailure calls next.ServeDNS when next is not nill, otherwise it will return, a ServerFailure -// and a nil error. +// NextOrFailure calls next.ServeDNS when next is not nill, otherwise it will return, a ServerFailure and a nil error. func NextOrFailure(name string, next Handler, ctx context.Context, w dns.ResponseWriter, r *dns.Msg) (int, error) { // nolint: golint if next != nil { if span := ot.SpanFromContext(ctx); span != nil { @@ -107,3 +106,6 @@ var TimeBuckets = prometheus.ExponentialBuckets(0.00025, 2, 16) // from 0.25ms t // 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") + +// ServerCtx is the context key to pass server address context to the plugins handling the request. +type ServerCtx struct{} |