func()

in grpcgcp/gcp_multiendpoint.go [296:377]
67 lines of code
21 McCabe index (conditional complexity)

func (gme *GCPMultiEndpoint) UpdateMultiEndpoints(meOpts *GCPMultiEndpointOptions) error {
	gme.mu.Lock()
	defer gme.mu.Unlock()
	if _, ok := meOpts.MultiEndpoints[meOpts.Default]; !ok {
		return fmt.Errorf("default MultiEndpoint %q missing options", meOpts.Default)
	}

	validPools := make(map[string]bool)
	for _, meo := range meOpts.MultiEndpoints {
		for _, e := range meo.Endpoints {
			validPools[e] = true
		}
	}

	// Add missing pools.
	for e := range validPools {
		if _, ok := gme.pools[e]; !ok {
			// This creates a ClientConn with the gRPC-GCP balancer managing connection pool.
			conn, err := gme.dialFunc(context.Background(), e, gme.opts...)
			if err != nil {
				return err
			}
			if gme.log.V(FINE) {
				gme.log.Infof("created new channel pool for %q endpoint.", e)
			}
			gme.pools[e] = newMonitoredConn(e, conn, gme)
		}
	}

	// Add new multi-endpoints and update existing.
	for name, meo := range meOpts.MultiEndpoints {
		if me, ok := gme.mes[name]; ok {
			// Updating existing MultiEndpoint.
			me.SetEndpoints(meo.Endpoints)
			continue
		}

		// Add new MultiEndpoint.
		if gme.log.V(FINE) {
			gme.log.Infof("creating new %q multiendpoint.", name)
		}
		me, err := multiendpoint.NewMultiEndpoint(meo)
		if err != nil {
			return err
		}
		gme.mes[name] = me
	}
	gme.defaultName = meOpts.Default

	// Remove obsolete MultiEndpoints.
	for name := range gme.mes {
		if _, ok := meOpts.MultiEndpoints[name]; !ok {
			delete(gme.mes, name)
			if gme.log.V(FINE) {
				gme.log.Infof("removed obsolete %q multiendpoint.", name)
			}
		}
	}

	// Remove obsolete pools.
	for e, mc := range gme.pools {
		if _, ok := validPools[e]; !ok {
			if err := mc.conn.Close(); err != nil {
				gme.log.Errorf("error while closing the pool for %q endpoint: %v", e, err)
			}
			if gme.log.V(FINE) {
				gme.log.Infof("closed channel pool for %q endpoint.", e)
			}
			mc.stopMonitoring()
			delete(gme.pools, e)
		}
	}

	// Trigger status update.
	for e, mc := range gme.pools {
		s := mc.conn.GetState()
		for _, me := range gme.mes {
			me.SetEndpointAvailability(e, s == connectivity.Ready)
		}
	}
	return nil
}