scripts/metricsgen: add the initial version of metricsgen

Makefile

@@ -251,6 +251,21 @@ mockery:
 	go generate -run="./scripts/mockery_generate.sh" ./...
 .PHONY: mockery
 
+###############################################################################
+###                               Metrics                                   ###
+###############################################################################
+
+metrics: testdata-metrics
+	go generate -run="scripts/metricsgen" ./...
+.PHONY: metrics
+
+	# By convention, the go tool ignores subdirectories of directories named
+	# 'testdata'. This command invokes the generate command on the folder directly
+	# to avoid this.
+testdata-metrics:
+	ls ./scripts/metricsgen/testdata | xargs -I{} go generate -run="scripts/metricsgen" ./scripts/metricsgen/testdata/{}
+.PHONY: testdata-metrics
+
 ###############################################################################
 ###                       Local testnet using docker                        ###
 ###############################################################################

internal/state/indexer/metrics.go

@@ -2,12 +2,10 @@ package indexer
 
 import (
 	"github.com/go-kit/kit/metrics"
-	"github.com/go-kit/kit/metrics/discard"
-
-	prometheus "github.com/go-kit/kit/metrics/prometheus"
-	stdprometheus "github.com/prometheus/client_golang/prometheus"
 )
 
+//go:generate go run github.com/tendermint/tendermint/scripts/metricsgen -struct=Metrics
+
 // MetricsSubsystem is a the subsystem label for the indexer package.
 const MetricsSubsystem = "indexer"
 
@@ -25,49 +23,3 @@ type Metrics struct {
 	// Number of transactions indexed.
 	TransactionsIndexed metrics.Counter
 }
-
-// PrometheusMetrics returns Metrics build using Prometheus client library.
-// Optionally, labels can be provided along with their values ("foo",
-// "fooValue").
-func PrometheusMetrics(namespace string, labelsAndValues ...string) *Metrics {
-	labels := []string{}
-	for i := 0; i < len(labelsAndValues); i += 2 {
-		labels = append(labels, labelsAndValues[i])
-	}
-	return &Metrics{
-		BlockEventsSeconds: prometheus.NewHistogramFrom(stdprometheus.HistogramOpts{
-			Namespace: namespace,
-			Subsystem: MetricsSubsystem,
-			Name:      "block_events_seconds",
-			Help:      "Latency for indexing block events.",
-		}, labels).With(labelsAndValues...),
-		TxEventsSeconds: prometheus.NewHistogramFrom(stdprometheus.HistogramOpts{
-			Namespace: namespace,
-			Subsystem: MetricsSubsystem,
-			Name:      "tx_events_seconds",
-			Help:      "Latency for indexing transaction events.",
-		}, labels).With(labelsAndValues...),
-		BlocksIndexed: prometheus.NewCounterFrom(stdprometheus.CounterOpts{
-			Namespace: namespace,
-			Subsystem: MetricsSubsystem,
-			Name:      "blocks_indexed",
-			Help:      "Number of complete blocks indexed.",
-		}, labels).With(labelsAndValues...),
-		TransactionsIndexed: prometheus.NewCounterFrom(stdprometheus.CounterOpts{
-			Namespace: namespace,
-			Subsystem: MetricsSubsystem,
-			Name:      "transactions_indexed",
-			Help:      "Number of transactions indexed.",
-		}, labels).With(labelsAndValues...),
-	}
-}
-
-// NopMetrics returns an indexer metrics stub that discards all samples.
-func NopMetrics() *Metrics {
-	return &Metrics{
-		BlockEventsSeconds:  discard.NewHistogram(),
-		TxEventsSeconds:     discard.NewHistogram(),
-		BlocksIndexed:       discard.NewCounter(),
-		TransactionsIndexed: discard.NewCounter(),
-	}
-}