Method UpdateSession

pkg/session/store.go:209–251

UpdateSession updates an existing session, or creates it if it doesn't exist (upsert). This enables lazy session persistence - sessions are only stored when they have content. Note: Like SQLite, this only stores metadata. Messages are stored separately via AddMessage.

(_ context.Context, session *Session)

// This enables lazy session persistence - sessions are only stored when they have content.
// Note: Like SQLite, this only stores metadata. Messages are stored separately via AddMessage.
func (s *InMemorySessionStore) UpdateSession(_ context.Context, session *Session) error {
	if session.ID == "" {
		return ErrEmptyID
	}

	// Snapshot the input session under its mu so the field copy
	// doesn't race with concurrent writers (e.g. the runtime stream
	// goroutine updating token counts via SetUsage).
	// MAINTENANCE: when adding new persisted fields to Session, add them here too.
	session.mu.RLock()
	newSession := &Session{
		ID:                  session.ID,
		Title:               session.Title,
		Evals:               session.Evals,
		CreatedAt:           session.CreatedAt,
		ToolsApproved:       session.ToolsApproved,
		HideToolResults:     session.HideToolResults,
		WorkingDir:          session.WorkingDir,
		SendUserMessage:     session.SendUserMessage,
		MaxIterations:       session.MaxIterations,
		Starred:             session.Starred,
		InputTokens:         session.InputTokens,
		OutputTokens:        session.OutputTokens,
		Cost:                session.Cost,
		Permissions:         clonePermissionsConfig(session.Permissions),
		AgentModelOverrides: cloneStringMap(session.AgentModelOverrides),
		CustomModelsUsed:    cloneStringSlice(session.CustomModelsUsed),
		AttachedFiles:       slices.Clone(session.AttachedFiles),
		ParentID:            session.ParentID,
	}
	session.mu.RUnlock()

	// Preserve existing messages if session already exists
	if existing, exists := s.sessions.Load(session.ID); exists {
		existing.mu.RLock()
		newSession.Messages = make([]Item, len(existing.Messages))
		copy(newSession.Messages, existing.Messages)
		existing.mu.RUnlock()
	}

	s.sessions.Store(session.ID, newSession)
	return nil
}

// SetSessionStarred sets the starred status of a session.
func (s *InMemorySessionStore) SetSessionStarred(_ context.Context, id string, starred bool) error {