From 705090c6035835d632bb5db952b2c6ce467d6f74 Mon Sep 17 00:00:00 2001
From: Andrew Davis <1709934+Savid@users.noreply.github.com>
Date: Mon, 14 Nov 2022 15:36:15 +1000
Subject: [PATCH] feat(sentry): metrics

---
 cmd/sentry.go        |  8 ++++++++
 example_sentry.yaml  |  3 +++
 pkg/sentry/config.go |  3 +++
 pkg/sentry/sentry.go | 25 +++++++++++++++++++++++++
 4 files changed, 39 insertions(+)

diff --git a/cmd/sentry.go b/cmd/sentry.go
index 007ca9c5..0cfb4c28 100644
--- a/cmd/sentry.go
+++ b/cmd/sentry.go
@@ -5,6 +5,7 @@ import (
 
 	"github.com/creasty/defaults"
 	"github.com/ethpandaops/xatu/pkg/sentry"
+	"github.com/sirupsen/logrus"
 	"github.com/spf13/cobra"
 	"gopkg.in/yaml.v2"
 )
@@ -31,6 +32,13 @@ var sentryCmd = &cobra.Command{
 
 		log.Info("Config loaded")
 
+		logLevel, err := logrus.ParseLevel(config.LoggingLevel)
+		if err != nil {
+			log.WithField("logLevel", config.LoggingLevel).Fatal("invalid logging level")
+		}
+
+		log.SetLevel(logLevel)
+
 		sentry, err := sentry.New(cmd.Context(), log, config)
 		if err != nil {
 			log.Fatal(err)
diff --git a/example_sentry.yaml b/example_sentry.yaml
index 63b502fe..3d5b717c 100644
--- a/example_sentry.yaml
+++ b/example_sentry.yaml
@@ -1,3 +1,6 @@
+logging: "debug" # panic,fatal,warm,info,debug,trace
+metricsAddr: ":9090"
+
 name: example-instance
 
 labels:
diff --git a/pkg/sentry/config.go b/pkg/sentry/config.go
index 2c1353e0..47a9f05d 100644
--- a/pkg/sentry/config.go
+++ b/pkg/sentry/config.go
@@ -9,6 +9,9 @@ import (
 )
 
 type Config struct {
+	LoggingLevel string `yaml:"logging" default:"info"`
+	MetricsAddr  string `yaml:"metricsAddr" default:":9090"`
+
 	// The name of the sentry
 	Name string `yaml:"name"`
 
diff --git a/pkg/sentry/sentry.go b/pkg/sentry/sentry.go
index 0d419bfa..5bd751d9 100644
--- a/pkg/sentry/sentry.go
+++ b/pkg/sentry/sentry.go
@@ -3,6 +3,7 @@ package sentry
 import (
 	"context"
 	"errors"
+	"net/http"
 	"os"
 	"os/signal"
 	"runtime"
@@ -14,6 +15,7 @@ import (
 	"github.com/ethpandaops/xatu/pkg/sentry/ethereum"
 	"github.com/ethpandaops/xatu/pkg/sentry/output"
 	"github.com/go-co-op/gocron"
+	"github.com/prometheus/client_golang/prometheus/promhttp"
 	"github.com/sirupsen/logrus"
 	"google.golang.org/protobuf/types/known/timestamppb"
 )
@@ -59,6 +61,10 @@ func New(ctx context.Context, log logrus.FieldLogger, config *Config) (*Sentry,
 }
 
 func (s *Sentry) Start(ctx context.Context) error {
+	if err := s.ServeMetrics(ctx); err != nil {
+		return err
+	}
+
 	s.log.WithField("version", xatu.Full()).Info("Starting Xatu in sentry mode")
 
 	s.beacon.OnReady(ctx, func(ctx context.Context) error {
@@ -108,6 +114,25 @@ func (s *Sentry) Start(ctx context.Context) error {
 	return nil
 }
 
+func (s *Sentry) ServeMetrics(ctx context.Context) error {
+	go func() {
+		server := &http.Server{
+			Addr:              s.Config.MetricsAddr,
+			ReadHeaderTimeout: 15 * time.Second,
+		}
+
+		server.Handler = promhttp.Handler()
+
+		s.log.Infof("Serving metrics at %s", s.Config.MetricsAddr)
+
+		if err := server.ListenAndServe(); err != nil {
+			s.log.Fatal(err)
+		}
+	}()
+
+	return nil
+}
+
 func (s *Sentry) createNewClientMeta(ctx context.Context, topic xatu.ClientMeta_Event_Name) (*xatu.ClientMeta, error) {
 	network, err := s.beacon.Metadata().NetworkName()
 	if err != nil {