plugin/forward Add rcode and rtype to request_duration_seconds metric (#4391)

* plugin/forward Add rcode and rtype to request_duration_seconds metric

Signed-off-by: Maxime Ginters <maxime.ginters@shopify.com>

* Control the cardinality of query type

Signed-off-by: Maxime Ginters <maxime.ginters@shopify.com>

1 files changed, 4 insertions, 33 deletions

diff --git a/plugin/metrics/vars/report.go b/plugin/metrics/vars/report.go
index 96b29d9fb..9bad43582 100644
--- a/plugin/metrics/vars/report.go
+++ b/plugin/metrics/vars/report.go
@@ -3,9 +3,8 @@ package vars
 import (
 	"time"
 
+	"github.com/coredns/coredns/plugin/pkg/dnsutil"
 	"github.com/coredns/coredns/request"
-
-	"github.com/miekg/dns"
 )
 
 // Report reports the metrics data associated with request. This function is exported because it is also
@@ -19,45 +18,17 @@ func Report(server string, req request.Request, zone, rcode string, size int, st
 		fam = "2"
 	}
 
-	typ := req.QType()
+	qtype := dnsutil.QTypeMonitorLabel(req.QType())
 
 	if req.Do() {
 		RequestDo.WithLabelValues(server, zone).Inc()
 	}
 
-	if _, known := monitorType[typ]; known {
-		RequestCount.WithLabelValues(server, zone, net, fam, dns.Type(typ).String()).Inc()
-		RequestDuration.WithLabelValues(server, zone, dns.Type(typ).String()).Observe(time.Since(start).Seconds())
-	} else {
-		RequestCount.WithLabelValues(server, zone, net, fam, other).Inc()
-		RequestDuration.WithLabelValues(server, zone, other).Observe(time.Since(start).Seconds())
-	}
+	RequestCount.WithLabelValues(server, zone, net, fam, qtype).Inc()
+	RequestDuration.WithLabelValues(server, zone, qtype).Observe(time.Since(start).Seconds())
 
 	ResponseSize.WithLabelValues(server, zone, net).Observe(float64(size))
 	RequestSize.WithLabelValues(server, zone, net).Observe(float64(req.Len()))
 
 	ResponseRcode.WithLabelValues(server, zone, rcode).Inc()
 }
-
-var monitorType = map[uint16]struct{}{
-	dns.TypeAAAA:   {},
-	dns.TypeA:      {},
-	dns.TypeCNAME:  {},
-	dns.TypeDNSKEY: {},
-	dns.TypeDS:     {},
-	dns.TypeMX:     {},
-	dns.TypeNSEC3:  {},
-	dns.TypeNSEC:   {},
-	dns.TypeNS:     {},
-	dns.TypePTR:    {},
-	dns.TypeRRSIG:  {},
-	dns.TypeSOA:    {},
-	dns.TypeSRV:    {},
-	dns.TypeTXT:    {},
-	// Meta Qtypes
-	dns.TypeIXFR: {},
-	dns.TypeAXFR: {},
-	dns.TypeANY:  {},
-}
-
-const other = "other"