Address PR feedback: fix race condition and encapsulation issues

- Fix race condition in LocalStorage.Close() by collecting keys before deletion
- Update Close() comment to reflect actual behavior (clears sessions, not a no-op)
- Add setter methods (setTimestamps, setMetadataMap) to ProxySession for proper encapsulation
- Update serialization to use setter methods instead of direct field access
- Fix StreamableSession constructor to use NewTypedProxySession for proper initialization
- Add type assertion check in StreamableSession deserialization

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <[email protected]>

Author: JAORMX

pkg/transport/session/proxy_session.go

@@ -134,3 +134,24 @@ func (s *ProxySession) DeleteMetadata(key string) {
 	defer s.mu.Unlock()
 	delete(s.metadata, key)
 }
+
+// setTimestamps updates the created and updated timestamps.
+// This is used internally for deserialization to restore session state.
+func (s *ProxySession) setTimestamps(created, updated time.Time) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	s.created = created
+	s.updated = updated
+}
+
+// setMetadataMap replaces the entire metadata map.
+// This is used internally for deserialization to restore session state.
+func (s *ProxySession) setMetadataMap(metadata map[string]string) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if metadata == nil {
+		s.metadata = make(map[string]string)
+	} else {
+		s.metadata = metadata
+	}
+}

pkg/transport/session/serialization.go

@@ -68,28 +68,23 @@ func deserializeSession(data []byte) (Session, error) {
 		// Use existing NewSSESession constructor
 		sseSession := NewSSESession(sd.ID)
 		// Update timestamps to match stored values
-		sseSession.created = sd.CreatedAt
-		sseSession.updated = sd.UpdatedAt
+		sseSession.setTimestamps(sd.CreatedAt, sd.UpdatedAt)
 		// Restore metadata
-		sseSession.metadata = sd.Metadata
-		if sseSession.metadata == nil {
-			sseSession.metadata = make(map[string]string)
-		}
+		sseSession.setMetadataMap(sd.Metadata)
 		// Note: SSE channels and client info will be recreated when reconnected
 		session = sseSession
 
 	case SessionTypeStreamable:
 		// Use existing NewStreamableSession constructor
-		streamSession := NewStreamableSession(sd.ID).(*StreamableSession)
+		sess := NewStreamableSession(sd.ID)
+		streamSession, ok := sess.(*StreamableSession)
+		if !ok {
+			return nil, fmt.Errorf("failed to create StreamableSession")
+		}
 		// Update timestamps to match stored values
-		streamSession.created = sd.CreatedAt
-		streamSession.updated = sd.UpdatedAt
-		streamSession.sessType = SessionTypeStreamable
+		streamSession.setTimestamps(sd.CreatedAt, sd.UpdatedAt)
 		// Restore metadata
-		streamSession.metadata = sd.Metadata
-		if streamSession.metadata == nil {
-			streamSession.metadata = make(map[string]string)
-		}
+		streamSession.setMetadataMap(sd.Metadata)
 		session = streamSession
 
 	case SessionTypeMCP:
@@ -98,13 +93,9 @@ func deserializeSession(data []byte) (Session, error) {
 		// Use existing NewTypedProxySession constructor
 		proxySession := NewTypedProxySession(sd.ID, sd.Type)
 		// Update timestamps to match stored values
-		proxySession.created = sd.CreatedAt
-		proxySession.updated = sd.UpdatedAt
+		proxySession.setTimestamps(sd.CreatedAt, sd.UpdatedAt)
 		// Restore metadata
-		proxySession.metadata = sd.Metadata
-		if proxySession.metadata == nil {
-			proxySession.metadata = make(map[string]string)
-		}
+		proxySession.setMetadataMap(sd.Metadata)
 		session = proxySession
 	}
 

pkg/transport/session/storage_local.go

@@ -94,13 +94,18 @@ func (s *LocalStorage) DeleteExpired(ctx context.Context, before time.Time) erro
 	return nil
 }
 
-// Close is a no-op for local storage as there are no resources to clean up.
+// Close clears all sessions from local storage.
 func (s *LocalStorage) Close() error {
-	// Clear all sessions on close
+	// Collect keys first to avoid modifying map during iteration
+	var toDelete []any
 	s.sessions.Range(func(key, _ any) bool {
-		s.sessions.Delete(key)
+		toDelete = append(toDelete, key)
 		return true
 	})
+	// Clear all sessions
+	for _, key := range toDelete {
+		s.sessions.Delete(key)
+	}
 	return nil
 }
 

pkg/transport/session/streamable_session.go

@@ -17,7 +17,7 @@ type StreamableSession struct {
 // NewStreamableSession constructs a new streamable session with buffered channels
 func NewStreamableSession(id string) Session {
 	return &StreamableSession{
-		ProxySession: &ProxySession{id: id},
+		ProxySession: NewTypedProxySession(id, SessionTypeStreamable),
 		MessageCh:    make(chan jsonrpc2.Message, 100),
 		ResponseCh:   make(chan jsonrpc2.Message, 100),
 	}