Method doExpireOldAgents

coderd/tailnet.go:482–520

(ctx context.Context, cutoff time.Duration)

}

func (m *MultiAgentController) doExpireOldAgents(ctx context.Context, cutoff time.Duration) {
	// TODO: add some attrs to this.
	ctx, span := m.tracer.Start(ctx, tracing.FuncName())
	defer span.End()

	start := time.Now()
	deletedCount := 0

	m.mu.Lock()
	defer m.mu.Unlock()
	m.logger.Debug(ctx, "pruning inactive agents", slog.F("agent_count", len(m.connectionTimes)))
	for agentID, lastConnection := range m.connectionTimes {
		// If no one has connected since the cutoff and there are no active
		// connections, remove the agent.
		if time.Since(lastConnection) > cutoff && len(m.tickets[agentID]) == 0 {
			if m.coordination != nil {
				err := m.coordination.SendRequest(&proto.CoordinateRequest{
					RemoveTunnel: &proto.CoordinateRequest_Tunnel{Id: agentID[:]},
				})
				if err != nil {
					m.logger.Debug(ctx, "unsubscribe expired agent", slog.Error(err), slog.F("agent_id", agentID))
					m.coordination.SendErr(xerrors.Errorf("unsubscribe expired agent: %w", err))
					// close the client because we do not want to do a graceful disconnect by
					// closing the coordination.
					_ = m.coordination.CloseClient()
					m.coordination = nil
					// Here we continue deleting any inactive agents: there is no point in
					// re-establishing tunnels to expired agents when we eventually reconnect.
				}
			}
			deletedCount++
			delete(m.connectionTimes, agentID)
		}
	}
	m.logger.Debug(ctx, "pruned inactive agents",
		slog.F("deleted", deletedCount),
		slog.F("took", time.Since(start)),
	)
}

func (m *MultiAgentController) Close() {
	m.cancel()