users service: add sessions (#17744)

* users: add cache to service

* reflect review comments

app/server.go

@@ -135,7 +135,6 @@ type Server struct {
 	newStore func() (store.Store, error)
 
 	htmlTemplateWatcher     *templates.Container
-	sessionCache            cache.Cache
 	seenPendingPostIdsCache cache.Cache
 	statusCache             cache.Cache
 	configListenerId        string
@@ -328,13 +327,6 @@ func NewServer(options ...Option) (*Server, error) {
 	}
 
 	var err error
-	if s.sessionCache, err = s.CacheProvider.NewCache(&cache.CacheOptions{
-		Size:           model.SESSION_CACHE_SIZE,
-		Striped:        true,
-		StripedBuckets: maxInt(runtime.NumCPU()-1, 1),
-	}); err != nil {
-		return nil, errors.Wrap(err, "Unable to create session cache")
-	}
 	if s.seenPendingPostIdsCache, err = s.CacheProvider.NewCache(&cache.CacheOptions{
 		Size: PendingPostIDsCacheSize,
 	}); err != nil {
@@ -413,7 +405,16 @@ func NewServer(options ...Option) (*Server, error) {
 		return nil, errors.Wrap(err, "cannot create store")
 	}
 
-	s.userService = users.New(s.Store.User(), s.Config)
+	s.userService, err = users.New(users.ServiceInitializer{
+		UserStore:    s.Store.User(),
+		SessionStore: s.Store.Session(),
+		ConfigFn:     s.Config,
+		Metrics:      s.Metrics,
+		Cluster:      s.Cluster,
+	})
+	if err != nil {
+		return nil, errors.Wrapf(err, "unable to create users service")
+	}
 
 	s.configListenerId = s.AddConfigListener(func(_, _ *model.Config) {
 		s.configOrLicenseListener()