From 5368c4207a710919bb8fea902a6c632baa8ca431 Mon Sep 17 00:00:00 2001
From: Evgenii Stratonikov <e.stratonikov@yadro.com>
Date: Tue, 21 Mar 2023 16:51:21 +0300
Subject: [PATCH] [#156] services/tree: Split syncLoop() in functions

Signed-off-by: Evgenii Stratonikov <e.stratonikov@yadro.com>
---
 pkg/services/tree/sync.go | 158 ++++++++++++++++++++------------------
 1 file changed, 85 insertions(+), 73 deletions(-)

diff --git a/pkg/services/tree/sync.go b/pkg/services/tree/sync.go
index 9fe24fed..d4ef7df5 100644
--- a/pkg/services/tree/sync.go
+++ b/pkg/services/tree/sync.go
@@ -246,7 +246,6 @@ func (s *Service) SynchronizeAll() error {
 	}
 }
 
-// nolint: funlen, gocognit
 func (s *Service) syncLoop(ctx context.Context) {
 	for {
 		select {
@@ -263,86 +262,99 @@ func (s *Service) syncLoop(ctx context.Context) {
 				continue
 			}
 
-			newMap := make(map[cid.ID]struct{}, len(s.cnrMap))
-			cnrsToSync := make([]cid.ID, 0, len(cnrs))
+			newMap, cnrsToSync := s.containersToSync(cnrs)
 
-			var removed []cid.ID
-			for _, cnr := range cnrs {
-				_, pos, err := s.getContainerNodes(cnr)
-				if err != nil {
-					s.log.Error("could not calculate container nodes",
-						zap.Stringer("cid", cnr),
-						zap.Error(err))
-					continue
-				}
+			s.syncContainers(ctx, cnrsToSync)
 
-				if pos < 0 {
-					// node is not included in the container.
-					continue
-				}
-
-				newMap[cnr] = struct{}{}
-				cnrsToSync = append(cnrsToSync, cnr)
-			}
-
-			// sync new containers
-			var wg sync.WaitGroup
-			for _, cnr := range cnrsToSync {
-				wg.Add(1)
-				cnr := cnr
-				err := s.syncPool.Submit(func() {
-					defer wg.Done()
-					s.log.Debug("syncing container trees...", zap.Stringer("cid", cnr))
-
-					err := s.synchronizeAllTrees(ctx, cnr)
-					if err != nil {
-						s.log.Error("could not sync trees", zap.Stringer("cid", cnr), zap.Error(err))
-						return
-					}
-
-					s.log.Debug("container trees have been synced", zap.Stringer("cid", cnr))
-				})
-				if err != nil {
-					wg.Done()
-					s.log.Error("could not query trees for synchronization",
-						zap.Stringer("cid", cnr),
-						zap.Error(err))
-					if errors.Is(err, ants.ErrPoolClosed) {
-						return
-					}
-				}
-			}
-			wg.Wait()
-
-			s.cnrMapMtx.Lock()
-			for cnr := range s.cnrMap {
-				if _, ok := newMap[cnr]; ok {
-					continue
-				}
-				removed = append(removed, cnr)
-			}
-			for i := range removed {
-				delete(s.cnrMap, removed[i])
-			}
-			s.cnrMapMtx.Unlock()
-
-			for _, cnr := range removed {
-				s.log.Debug("removing redundant trees...", zap.Stringer("cid", cnr))
-
-				err = s.DropTree(ctx, cnr, "")
-				if err != nil {
-					s.log.Error("could not remove redundant tree",
-						zap.Stringer("cid", cnr),
-						zap.Error(err))
-					continue
-				}
-			}
+			s.removeContainers(ctx, newMap)
 
 			s.log.Debug("trees have been synchronized")
 		}
 	}
 }
 
+func (s *Service) syncContainers(ctx context.Context, cnrs []cid.ID) {
+	// sync new containers
+	var wg sync.WaitGroup
+	for _, cnr := range cnrs {
+		wg.Add(1)
+		cnr := cnr
+		err := s.syncPool.Submit(func() {
+			defer wg.Done()
+			s.log.Debug("syncing container trees...", zap.Stringer("cid", cnr))
+
+			err := s.synchronizeAllTrees(ctx, cnr)
+			if err != nil {
+				s.log.Error("could not sync trees", zap.Stringer("cid", cnr), zap.Error(err))
+				return
+			}
+
+			s.log.Debug("container trees have been synced", zap.Stringer("cid", cnr))
+		})
+		if err != nil {
+			wg.Done()
+			s.log.Error("could not query trees for synchronization",
+				zap.Stringer("cid", cnr),
+				zap.Error(err))
+			if errors.Is(err, ants.ErrPoolClosed) {
+				return
+			}
+		}
+	}
+	wg.Wait()
+}
+
+func (s *Service) removeContainers(ctx context.Context, newContainers map[cid.ID]struct{}) {
+	s.cnrMapMtx.Lock()
+	defer s.cnrMapMtx.Unlock()
+
+	var removed []cid.ID
+	for cnr := range s.cnrMap {
+		if _, ok := newContainers[cnr]; ok {
+			continue
+		}
+		removed = append(removed, cnr)
+	}
+	for i := range removed {
+		delete(s.cnrMap, removed[i])
+	}
+
+	for _, cnr := range removed {
+		s.log.Debug("removing redundant trees...", zap.Stringer("cid", cnr))
+
+		err := s.DropTree(ctx, cnr, "")
+		if err != nil {
+			s.log.Error("could not remove redundant tree",
+				zap.Stringer("cid", cnr),
+				zap.Error(err))
+		}
+	}
+}
+
+func (s *Service) containersToSync(cnrs []cid.ID) (map[cid.ID]struct{}, []cid.ID) {
+	newMap := make(map[cid.ID]struct{}, len(s.cnrMap))
+	cnrsToSync := make([]cid.ID, 0, len(cnrs))
+
+	for _, cnr := range cnrs {
+		_, pos, err := s.getContainerNodes(cnr)
+		if err != nil {
+			s.log.Error("could not calculate container nodes",
+				zap.Stringer("cid", cnr),
+				zap.Error(err))
+			continue
+		}
+
+		if pos < 0 {
+			// node is not included in the container.
+			continue
+		}
+
+		newMap[cnr] = struct{}{}
+		cnrsToSync = append(cnrsToSync, cnr)
+	}
+	return newMap, cnrsToSync
+}
+
 // randomizeNodeOrder shuffles nodes and removes not a `pos` index.
 // It is assumed that 0 <= pos < len(nodes).
 func randomizeNodeOrder(cnrNodes []netmap.NodeInfo, pos int) []netmap.NodeInfo {