refactor: use a single metrics instantiation instead of handling it per component

op-batcher/batcher/batch_submitter.go

@@ -12,7 +12,6 @@ import (
 	"github.com/ethereum-optimism/optimism/op-batcher/rpc"
 	opservice "github.com/ethereum-optimism/optimism/op-service"
 	oplog "github.com/ethereum-optimism/optimism/op-service/log"
-	opmetrics "github.com/ethereum-optimism/optimism/op-service/metrics"
 	"github.com/ethereum-optimism/optimism/op-service/opio"
 	oppprof "github.com/ethereum-optimism/optimism/op-service/pprof"
 	oprpc "github.com/ethereum-optimism/optimism/op-service/rpc"
@@ -83,8 +82,7 @@ func Main(version string, cliCtx *cli.Context) error {
 		oprpc.WithLogger(l),
 	)
 	if cfg.RPCFlag.EnableAdmin {
-		rpcMetrics := opmetrics.NewRPCMetrics(procName, metrics.Namespace)
-		adminAPI := rpc.NewAdminAPI(batchSubmitter, rpcMetrics, l)
+		adminAPI := rpc.NewAdminAPI(batchSubmitter, &m.RPCMetrics, l)
 		server.AddAPI(rpc.GetAdminAPI(adminAPI))
 		l.Info("Admin RPC enabled")
 	}

op-batcher/metrics/metrics.go

@@ -51,6 +51,7 @@ type Metrics struct {
 
 	opmetrics.RefMetrics
 	txmetrics.TxMetrics
+	opmetrics.RPCMetrics
 
 	info prometheus.GaugeVec
 	up   prometheus.Gauge
@@ -93,6 +94,7 @@ func NewMetrics(procName string) *Metrics {
 
 		RefMetrics: opmetrics.MakeRefMetrics(ns, factory),
 		TxMetrics:  txmetrics.MakeTxMetrics(ns, factory),
+		RPCMetrics: opmetrics.MakeRPCMetrics(ns, factory),
 
 		info: *factory.NewGaugeVec(prometheus.GaugeOpts{
 			Namespace: ns,

op-node/metrics/metrics.go

@@ -80,7 +80,7 @@ type Metrics struct {
 	Info *prometheus.GaugeVec
 	Up   prometheus.Gauge
 
-	*metrics.RPCMetrics
+	metrics.RPCMetrics
 
 	L1SourceCache *CacheMetrics
 	L2SourceCache *CacheMetrics
@@ -175,7 +175,7 @@ func NewMetrics(procName string) *Metrics {
 			Help:      "1 if the op node has finished starting up",
 		}),
 
-		RPCMetrics: metrics.NewRPCMetrics(procName, Namespace),
+		RPCMetrics: metrics.MakeRPCMetrics(ns, factory),
 
 		L1SourceCache: NewCacheMetrics(factory, ns, "l1_source_cache", "L1 Source cache"),
 		L2SourceCache: NewCacheMetrics(factory, ns, "l2_source_cache", "L2 Source cache"),

op-service/metrics/rpc_metrics.go

@@ -7,7 +7,6 @@ import (
 	"github.com/ethereum/go-ethereum"
 	"github.com/ethereum/go-ethereum/rpc"
 	"github.com/prometheus/client_golang/prometheus"
-	"github.com/prometheus/client_golang/prometheus/collectors"
 )
 
 const (
@@ -30,20 +29,10 @@ type RPCMetrics struct {
 	RPCClientResponsesTotal         *prometheus.CounterVec
 }
 
-// NewRPCMetrics creates a new RPCMetrics instance with the given process name, and
+// MakeRPCMetrics creates a new RPCMetrics instance with the given process name, and
 // namespace for the service.
-func NewRPCMetrics(procName, namespace string) *RPCMetrics {
-	if procName == "" {
-		procName = "default"
-	}
-	ns := namespace + "_" + procName
-
-	registry := prometheus.NewRegistry()
-	registry.MustRegister(collectors.NewProcessCollector(collectors.ProcessCollectorOpts{}))
-	registry.MustRegister(collectors.NewGoCollector())
-	factory := With(registry)
-
-	return &RPCMetrics{
+func MakeRPCMetrics(ns string, factory Factory) RPCMetrics {
+	return RPCMetrics{
 		RPCServerRequestsTotal: factory.NewCounterVec(prometheus.CounterOpts{
 			Namespace: ns,
 			Subsystem: RPCServerSubsystem,