rpcsrv: remove deprecated RPC counters

ROADMAP.md

@@ -50,15 +50,6 @@ Receive* APIs.
 
 Removal of these APIs is scheduled for May 2023 (~0.103.0 release).
 
-## Prometheus RPC counters
-
-A number of neogo_${method}_called Prometheus counters are marked as
-deprecated since version 0.99.5, neogo_rpc_${method}_time histograms can be
-used instead (that also have a counter).
-
-It's not a frequently used thing and it's easy to replace it, so removal of
-old counters is scheduled for January-February 2023 (~0.100.X release).
-
 ## SecondsPerBlock protocol configuration
 
 With 0.100.0 version SecondsPerBlock protocol configuration setting was

pkg/services/rpcsrv/prometheus.go

@@ -1,7 +1,6 @@
 package rpcsrv
 
 import (
-	"fmt"
 	"strings"
 	"time"
 
@@ -10,7 +9,6 @@ import (
 
 // Metrics used in monitoring service.
 var (
-	rpcCounter = map[string]prometheus.Counter{}
 	rpcTimes = map[string]prometheus.Histogram{}
 )
 
@@ -19,22 +17,9 @@ func addReqTimeMetric(name string, t time.Duration) {
 	if ok {
 		hist.Observe(t.Seconds())
 	}
-	ctr, ok := rpcCounter[name]
-	if ok {
-		ctr.Inc()
-	}
 }
 
 func regCounter(call string) {
-	ctr := prometheus.NewCounter(
-		prometheus.CounterOpts{
-			Help:      fmt.Sprintf("Number of calls to %s rpc endpoint (obsolete, to be removed)", call),
-			Name:      fmt.Sprintf("%s_called", call),
-			Namespace: "neogo",
-		},
-	)
-	prometheus.MustRegister(ctr)
-	rpcCounter[call] = ctr
 	rpcTimes[call] = prometheus.NewHistogram(
 		prometheus.HistogramOpts{
 			Help:      "RPC " + call + " call handling time",