coredns/plugin/metrics/context.go
Chris O'Haver b56b080a7c
plugin/view: Advanced routing interface and new 'view' plugin (#5538)
* introduce new interface "dnsserver.Viewer", that allows a plugin implementing it to decide if a query should be routed into its server block.
* add new plugin "view", that uses the new interface to enable a user to define expression based conditions that must be met for a query to be routed to its server block.

Signed-off-by: Chris O'Haver <cohaver@infoblox.com>
2022-09-08 14:56:27 -04:00

37 lines
1,013 B
Go

package metrics
import (
"context"
"github.com/coredns/coredns/core/dnsserver"
)
// 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(dnsserver.Key{})
if srv == nil {
return ""
}
return srv.(*dnsserver.Server).Addr
}
// WithView returns the name of the view currently handling the request, if a view is defined.
//
// Basic usage with a metric:
//
// <metric>.WithLabelValues(metrics.WithView(ctx), labels..).Add(1)
func WithView(ctx context.Context) string {
v := ctx.Value(dnsserver.ViewKey{})
if v == nil {
return ""
}
return v.(string)
}