Add hook for logging errors and warnings

cmd/soroban-rpc/internal/daemon/metrics.go

@@ -16,13 +16,17 @@ import (
 )
 
 func (d *Daemon) registerMetrics() {
+	// LogMetricsHook is a metric which counts log lines emitted by soroban rpc
+	logMetricsHook := logmetrics.New(prometheusNamespace)
+	d.logger.AddHook(logMetricsHook)
+	for _, counter := range logMetricsHook {
+		d.metricsRegistry.MustRegister(counter)
+	}
+
 	buildInfoGauge := prometheus.NewGaugeVec(
 		prometheus.GaugeOpts{Namespace: prometheusNamespace, Subsystem: "build", Name: "info"},
 		[]string{"version", "goversion", "commit", "branch", "build_timestamp"},
 	)
-	// LogMetricsHook is a metric which counts log lines emitted by soroban rpc
-	LogMetricsHook := logmetrics.New(prometheusNamespace)
-	//
 	buildInfoGauge.With(prometheus.Labels{
 		"version":         config.Version,
 		"commit":          config.CommitHash,
@@ -34,10 +38,6 @@ func (d *Daemon) registerMetrics() {
 	d.metricsRegistry.MustRegister(prometheus.NewGoCollector())
 	d.metricsRegistry.MustRegister(prometheus.NewProcessCollector(prometheus.ProcessCollectorOpts{}))
 	d.metricsRegistry.MustRegister(buildInfoGauge)
-
-	for _, counter := range LogMetricsHook {
-		d.metricsRegistry.MustRegister(counter)
-	}
 }
 
 func (d *Daemon) MetricsRegistry() *prometheus.Registry {

cmd/soroban-rpc/internal/test/metrics_test.go

@@ -2,6 +2,12 @@ package test
 
 import (
 	"fmt"
+	"github.com/prometheus/client_golang/prometheus/testutil"
+	"github.com/sirupsen/logrus"
+	"github.com/stellar/go/support/errors"
+	supportlog "github.com/stellar/go/support/log"
+	"github.com/stellar/go/support/logmetrics"
+	"github.com/stretchr/testify/assert"
 	"io"
 	"net/http"
 	"net/url"
@@ -27,6 +33,19 @@ func TestMetrics(t *testing.T) {
 	require.Contains(t, metrics, buildMetric)
 }
 
+func TestLogMetrics(t *testing.T) {
+	logMetrics := logmetrics.New("log_metrics_test")
+	logger := supportlog.New()
+	logger.AddHook(logMetrics)
+
+	err := errors.Errorf("test-error")
+	logger.WithError(err).Error("test error 1")
+	logger.WithError(err).Error("test error 2")
+
+	val := testutil.ToFloat64(logMetrics[logrus.ErrorLevel])
+	assert.Equal(t, val, 2.0)
+}
+
 func getMetrics(test *Test) string {
 	metricsURL, err := url.JoinPath(test.adminURL(), "/metrics")
 	require.NoError(test.t, err)