From 80eb11b0c97fdaa43a3e9694783b984dcb44b0b7 Mon Sep 17 00:00:00 2001
From: kjuulh <contact@kjuulh.io>
Date: Mon, 14 Feb 2022 01:42:18 +0100
Subject: [PATCH] Add metrics

---
 main.go                             | 25 ++++++++++++++++++++-----
 pkg/application/projects/service.go |  4 ++--
 pkg/application/users/service.go    |  4 ++--
 3 files changed, 24 insertions(+), 9 deletions(-)

diff --git a/main.go b/main.go
index 23fec11..87fe703 100644
--- a/main.go
+++ b/main.go
@@ -6,9 +6,11 @@ import (
 	"github.com/docker/docker/api/types"
 	"github.com/docker/docker/client"
 	"github.com/eko/gocache/cache"
+	"github.com/eko/gocache/metrics"
 	"github.com/eko/gocache/store"
 	"github.com/gin-gonic/gin"
 	"github.com/go-co-op/gocron"
+	"github.com/prometheus/client_golang/prometheus/promhttp"
 	"go.uber.org/zap"
 	"go.uber.org/zap/zapcore"
 	"io/ioutil"
@@ -77,11 +79,20 @@ func BasicAuthMiddleware(l *zap.Logger, us *users.Service) gin.HandlerFunc {
 		c.Next()
 	}
 }
-func setupApi(l *zap.Logger, cc *cache.Cache, us *users.Service, ps *projects.Service) {
+func setupApi(l *zap.Logger, cc *cache.MetricCache, us *users.Service, ps *projects.Service) {
 	l.Info("Setting up serverctl setupApi (using gin)")
 
 	r := gin.Default()
 
+	promHandler := func() gin.HandlerFunc {
+		h := promhttp.Handler()
+
+		return func(c *gin.Context) {
+			h.ServeHTTP(c.Writer, c.Request)
+		}
+	}
+	r.GET("/metrics", promHandler())
+
 	r.POST("/auth/register", func(c *gin.Context) {
 		type RegisterUser struct {
 			Email    string `json:"email" binding:"required"`
@@ -185,22 +196,26 @@ func setupDocker(l *zap.Logger) *client.Client {
 
 	return cli
 }
-func setupCache(l *zap.Logger) *cache.Cache {
+func setupCache(l *zap.Logger) *cache.MetricCache {
 	l.Info("Setting up cache")
 	ristrettoCache, err := ristretto.NewCache(&ristretto.Config{
 		NumCounters: 1000,
 		MaxCost:     100_000_000,
 		BufferItems: 64,
 	})
+	promMetrics := metrics.NewPrometheus("serverctl")
+
 	if err != nil {
 		panic(err)
 	}
 	ristrettoStore := store.NewRistretto(ristrettoCache, nil)
-	cacheManager := cache.New(ristrettoStore)
 
-	return cacheManager
+	cacheManager := cache.New(ristrettoStore)
+	metricsCache := cache.NewMetric(promMetrics, cacheManager)
+
+	return metricsCache
 }
-func setupCron(l *zap.Logger, cm *cache.Cache, cc *client.Client) {
+func setupCron(l *zap.Logger, cm *cache.MetricCache, cc *client.Client) {
 	l.Info("Setting up job scheduler (cron)")
 
 	s := gocron.NewScheduler(time.UTC)
diff --git a/pkg/application/projects/service.go b/pkg/application/projects/service.go
index 7967158..e1c9839 100644
--- a/pkg/application/projects/service.go
+++ b/pkg/application/projects/service.go
@@ -10,10 +10,10 @@ import (
 type Service struct {
 	projectsRepository Repository
 	logger             *zap.Logger
-	cache              *cache.Cache
+	cache              *cache.MetricCache
 }
 
-func NewService(logger *zap.Logger, projectsRepository Repository, cache *cache.Cache) *Service {
+func NewService(logger *zap.Logger, projectsRepository Repository, cache *cache.MetricCache) *Service {
 	return &Service{
 		logger:             logger,
 		projectsRepository: projectsRepository,
diff --git a/pkg/application/users/service.go b/pkg/application/users/service.go
index bf7c192..77171bf 100644
--- a/pkg/application/users/service.go
+++ b/pkg/application/users/service.go
@@ -9,12 +9,12 @@ import (
 
 type Service struct {
 	logger         *zap.Logger
-	cache          *cache.Cache
+	cache          *cache.MetricCache
 	repository     Repository
 	passwordHasher PasswordHasher
 }
 
-func NewService(l *zap.Logger, ur Repository, c *cache.Cache) *Service {
+func NewService(l *zap.Logger, ur Repository, c *cache.MetricCache) *Service {
 	return &Service{
 		logger:         l,
 		repository:     ur,