[client] Feature/relay integration fix reconnection (#2405)

When a peer disconnects gracefully from the server and immediately connects back, then the server will clean up an incorrect peer instance from the in-memory store. In this fix the store checks the peers instance before deleting it.

relay/server/store.go

@@ -19,7 +19,7 @@ func NewStore() *Store {
 }
 
 // AddPeer adds a peer to the store
-// It distinguishes the peers by their ID
+// todo: consider to close peer conn if the peer already exists
 func (s *Store) AddPeer(peer *Peer) {
 	s.peersLock.Lock()
 	defer s.peersLock.Unlock()
@@ -30,6 +30,15 @@ func (s *Store) AddPeer(peer *Peer) {
 func (s *Store) DeletePeer(peer *Peer) {
 	s.peersLock.Lock()
 	defer s.peersLock.Unlock()
+
+	dp, ok := s.peers[peer.String()]
+	if !ok {
+		return
+	}
+	if dp != peer {
+		return
+	}
+
 	delete(s.peers, peer.String())
 }
 

relay/server/store_test.go

@@ -0,0 +1,30 @@
+package server
+
+import (
+	"testing"
+)
+
+func TestStore_DeletePeer(t *testing.T) {
+	s := NewStore()
+	p := NewPeer([]byte("peer_one"), nil, nil)
+	s.AddPeer(p)
+	s.DeletePeer(p)
+	if _, ok := s.Peer(p.String()); ok {
+		t.Errorf("peer was not deleted")
+	}
+}
+
+func TestStore_DeleteDeprecatedPeer(t *testing.T) {
+	s := NewStore()
+
+	p1 := NewPeer([]byte("peer_id"), nil, nil)
+	p2 := NewPeer([]byte("peer_id"), nil, nil)
+
+	s.AddPeer(p1)
+	s.AddPeer(p2)
+	s.DeletePeer(p1)
+
+	if _, ok := s.Peer(p2.String()); !ok {
+		t.Errorf("second peer was deleted")
+	}
+}