plugin/proxy: fix metrics (#1137)

Add Counter metrics and fix duration to use upstream name (and only use
it when we have one).

Fix the documentation to reflect this.

Fixes #1134

1 files changed, 3 insertions, 6 deletions

diff --git a/plugin/proxy/proxy.go b/plugin/proxy/proxy.go
index b2c713a53..f0e6eadad 100644
--- a/plugin/proxy/proxy.go
+++ b/plugin/proxy/proxy.go
@@ -80,9 +80,6 @@ func (p Proxy) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg) (
 		for time.Since(start) < tryDuration {
 			host := upstream.Select()
 			if host == nil {
-
-				RequestDuration.WithLabelValues(state.Proto(), upstream.Exchanger().Protocol(), upstream.From()).Observe(float64(time.Since(start) / time.Millisecond))
-
 				return dns.RcodeServerFailure, fmt.Errorf("%s: %s", errUnreachable, "no upstream host")
 			}
 
@@ -94,6 +91,8 @@ func (p Proxy) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg) (
 			atomic.AddInt64(&host.Conns, 1)
 			queryEpoch := msg.Epoch()
 
+			RequestCount.WithLabelValues(state.Proto(), upstream.Exchanger().Protocol(), familyToString(state.Family()), host.Name).Add(1)
+
 			reply, backendErr = upstream.Exchanger().Exchange(ctx, host.Name, state)
 
 			respEpoch := msg.Epoch()
@@ -108,7 +107,7 @@ func (p Proxy) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg) (
 			if backendErr == nil {
 				w.WriteMsg(reply)
 
-				RequestDuration.WithLabelValues(state.Proto(), upstream.Exchanger().Protocol(), upstream.From()).Observe(float64(time.Since(start) / time.Millisecond))
+				RequestDuration.WithLabelValues(state.Proto(), upstream.Exchanger().Protocol(), familyToString(state.Family()), host.Name).Observe(float64(time.Since(start) / time.Millisecond))
 
 				return 0, taperr
 			}
@@ -139,8 +138,6 @@ func (p Proxy) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg) (
 			}(host, timeout)
 		}
 
-		RequestDuration.WithLabelValues(state.Proto(), upstream.Exchanger().Protocol(), upstream.From()).Observe(float64(time.Since(start) / time.Millisecond))
-
 		return dns.RcodeServerFailure, fmt.Errorf("%s: %s", errUnreachable, backendErr)
 	}
 }