RemoteCache: Cleanup infra remote cache (#64381)

* add warning on Count

* add usagestats service

* fix typo

* remove unused glog

* remote cache stats collect

* add encrypt usage stat

* rename handler

* Update pkg/infra/remotecache/remotecache.go

Co-authored-by: Dan Cech <dcech@grafana.com>

* Update pkg/infra/remotecache/remotecache_test.go

---------

Co-authored-by: Dan Cech <dcech@grafana.com>

pkg/infra/remotecache/memcached_storage.go

@@ -12,7 +12,7 @@ import (
 
 const memcachedCacheType = "memcached"
 
-var ErrNotImplemented = errors.New("count not implemented")
+var ErrNotImplemented = errors.New("not implemented")
 
 type memcachedStorage struct {
 	c     *memcache.Client

pkg/infra/remotecache/remotecache.go

@@ -7,10 +7,8 @@ import (
 	"errors"
 	"time"
 
-	"github.com/go-kit/log"
-
 	"github.com/grafana/grafana/pkg/infra/db"
-	glog "github.com/grafana/grafana/pkg/infra/log"
+	"github.com/grafana/grafana/pkg/infra/usagestats"
 	"github.com/grafana/grafana/pkg/registry"
 	"github.com/grafana/grafana/pkg/services/secrets"
 	"github.com/grafana/grafana/pkg/setting"
@@ -30,7 +28,8 @@ const (
 	ServiceName = "RemoteCache"
 )
 
-func ProvideService(cfg *setting.Cfg, sqlStore db.DB, secretsService secrets.Service) (*RemoteCache, error) {
+func ProvideService(cfg *setting.Cfg, sqlStore db.DB, usageStats usagestats.Service,
+	secretsService secrets.Service) (*RemoteCache, error) {
 	var codec codec
 	if cfg.RemoteCacheOptions.Encryption {
 		codec = &encryptionCodec{secretsService}
@@ -44,12 +43,27 @@ func ProvideService(cfg *setting.Cfg, sqlStore db.DB, secretsService secrets.Ser
 	s := &RemoteCache{
 		SQLStore: sqlStore,
 		Cfg:      cfg,
-		log:      glog.New("cache.remote"),
 		client:   client,
 	}
+
+	usageStats.RegisterMetricsFunc(s.getUsageStats)
+
 	return s, nil
 }
 
+func (ds *RemoteCache) getUsageStats(ctx context.Context) (map[string]interface{}, error) {
+	stats := map[string]interface{}{}
+	stats["stats.remote_cache."+ds.Cfg.RemoteCacheOptions.Name+".count"] = 1
+	encryptVal := 0
+	if ds.Cfg.RemoteCacheOptions.Encryption {
+		encryptVal = 1
+	}
+
+	stats["stats.remote_cache.encrypt_enabled.count"] = encryptVal
+
+	return stats, nil
+}
+
 // CacheStorage allows the caller to set, get and delete items in the cache.
 // Cached items are stored as byte arrays and marshalled using "encoding/gob"
 // so any struct added to the cache needs to be registered with `remotecache.Register`
@@ -66,12 +80,12 @@ type CacheStorage interface {
 
 	// Count returns the number of items in the cache.
 	// Optionaly a prefix can be provided to only count items with that prefix
+	// DO NOT USE. Not available for memcached.
 	Count(ctx context.Context, prefix string) (int64, error)
 }
 
 // RemoteCache allows Grafana to cache data outside its own process
 type RemoteCache struct {
-	log      log.Logger
 	client   CacheStorage
 	SQLStore db.DB
 	Cfg      *setting.Cfg

pkg/infra/remotecache/remotecache_test.go

@@ -10,6 +10,7 @@ import (
 
 	"github.com/grafana/grafana/pkg/infra/db"
 	"github.com/grafana/grafana/pkg/infra/log"
+	"github.com/grafana/grafana/pkg/infra/usagestats"
 	"github.com/grafana/grafana/pkg/services/secrets/fakes"
 	"github.com/grafana/grafana/pkg/setting"
 )
@@ -29,7 +30,7 @@ func createTestClient(t *testing.T, opts *setting.RemoteCacheOptions, sqlstore d
 	cfg := &setting.Cfg{
 		RemoteCacheOptions: opts,
 	}
-	dc, err := ProvideService(cfg, sqlstore, fakes.NewFakeSecretsService())
+	dc, err := ProvideService(cfg, sqlstore, &usagestats.UsageStatsMock{}, fakes.NewFakeSecretsService())
 	require.Nil(t, err, "Failed to init client for test")
 
 	return dc
@@ -120,6 +121,24 @@ func canNotFetchExpiredItems(t *testing.T, client CacheStorage) {
 	assert.Equal(t, err, ErrCacheItemNotFound)
 }
 
+func TestCollectUsageStats(t *testing.T) {
+	wantMap := map[string]interface{}{
+		"stats.remote_cache.redis.count":           1,
+		"stats.remote_cache.encrypt_enabled.count": 1,
+	}
+	cfg := setting.NewCfg()
+	cfg.RemoteCacheOptions = &setting.RemoteCacheOptions{Name: redisCacheType, Encryption: true}
+
+	remoteCache := &RemoteCache{
+		Cfg: cfg,
+	}
+
+	stats, err := remoteCache.getUsageStats(context.Background())
+	require.NoError(t, err)
+
+	assert.EqualValues(t, wantMap, stats)
+}
+
 func TestCachePrefix(t *testing.T) {
 	db := db.InitTestDB(t)
 	cache := &databaseCache{

pkg/infra/remotecache/testing.go

@@ -6,6 +6,7 @@ import (
 	"github.com/stretchr/testify/require"
 
 	"github.com/grafana/grafana/pkg/infra/db"
+	"github.com/grafana/grafana/pkg/infra/usagestats"
 	"github.com/grafana/grafana/pkg/services/secrets/fakes"
 	"github.com/grafana/grafana/pkg/setting"
 )
@@ -23,7 +24,7 @@ func NewFakeStore(t *testing.T) *RemoteCache {
 
 	dc, err := ProvideService(&setting.Cfg{
 		RemoteCacheOptions: opts,
-	}, sqlStore, fakes.NewFakeSecretsService())
+	}, sqlStore, &usagestats.UsageStatsMock{}, fakes.NewFakeSecretsService())
 	require.NoError(t, err, "Failed to init remote cache for test")
 
 	return dc

pkg/infra/usagestats/statscollector/service.go

@@ -173,9 +173,6 @@ func (s *Service) collectSystemStats(ctx context.Context) (map[string]interface{
 	}
 
 	m["stats.avg_auth_token_per_user.count"] = avgAuthTokensPerUser
-	if s.cfg.RemoteCacheOptions != nil && s.cfg.RemoteCacheOptions.Name != "" {
-		m["stats.remote_cache."+s.cfg.RemoteCacheOptions.Name+".count"] = 1
-	}
 	m["stats.packaging."+s.cfg.Packaging+".count"] = 1
 	m["stats.distributor."+s.cfg.ReportingDistributor+".count"] = 1
 

pkg/infra/usagestats/statscollector/service_test.go

@@ -182,7 +182,6 @@ func TestCollectingUsageStats(t *testing.T) {
 	assert.EqualValues(t, 11, metrics["stats.data_keys.count"])
 	assert.EqualValues(t, 3, metrics["stats.active_data_keys.count"])
 	assert.EqualValues(t, 5, metrics["stats.public_dashboards.count"])
-	assert.EqualValues(t, 1, metrics["stats.remote_cache.database.count"])
 
 	assert.InDelta(t, int64(65), metrics["stats.uptime"], 6)
 }

pkg/services/contexthandler/auth_proxy_test.go

@@ -13,6 +13,7 @@ import (
 	"github.com/grafana/grafana/pkg/infra/log"
 	"github.com/grafana/grafana/pkg/infra/remotecache"
 	"github.com/grafana/grafana/pkg/infra/tracing"
+	"github.com/grafana/grafana/pkg/infra/usagestats"
 	"github.com/grafana/grafana/pkg/services/anonymous/anontest"
 	"github.com/grafana/grafana/pkg/services/auth/authtest"
 	"github.com/grafana/grafana/pkg/services/auth/jwt"
@@ -91,7 +92,7 @@ func getContextHandler(t *testing.T) *ContextHandler {
 	cfg.AuthProxyHeaderName = "X-Killa"
 	cfg.AuthProxyEnabled = true
 	cfg.AuthProxyHeaderProperty = "username"
-	remoteCacheSvc, err := remotecache.ProvideService(cfg, sqlStore, fakes.NewFakeSecretsService())
+	remoteCacheSvc, err := remotecache.ProvideService(cfg, sqlStore, &usagestats.UsageStatsMock{}, fakes.NewFakeSecretsService())
 	require.NoError(t, err)
 	userAuthTokenSvc := authtest.NewFakeUserAuthTokenService()
 	renderSvc := &fakeRenderService{}