rw_core/test/common_test.go - voltha-go - Gitiles

 /*
  * Copyright 2019-present Open Networking Foundation
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  * http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
 package test

 import (
 	"context"
 	"fmt"
 	"strings"
 	"sync"
 	"time"

 	"github.com/opencord/voltha-lib-go/v7/pkg/log"
 	"github.com/opencord/voltha-protos/v5/go/common"
 	ofp "github.com/opencord/voltha-protos/v5/go/openflow_13"

 	"github.com/golang/protobuf/ptypes/empty"
 	"github.com/opencord/voltha-protos/v5/go/voltha"
 )

 var retryInterval = 50 * time.Millisecond

 type isLogicalDeviceConditionSatisfied func(ld *voltha.LogicalDevice) bool
 type isLogicalDevicePortsConditionSatisfied func(ports []*voltha.LogicalPort) bool
 type isDeviceConditionSatisfied func(ld *voltha.Device) bool
 type isDevicePortsConditionSatisfied func(ports *voltha.Ports) bool
 type isDevicesConditionSatisfied func(ds *voltha.Devices) bool
 type isLogicalDevicesConditionSatisfied func(lds *voltha.LogicalDevices) bool
 type isConditionSatisfied func() bool

 func getContext() context.Context {
 	return context.Background()
 }

 func setRetryInterval(interval time.Duration) {
 	retryInterval = interval
 }

 func waitUntilDeviceReadiness(deviceID string,
 	timeout time.Duration,
 	verificationFunction isDeviceConditionSatisfied,
 	nbi voltha.VolthaServiceClient) error {
 	ch := make(chan int, 1)
 	done := false
 	go func() {
 		for {
 			device, _ := nbi.GetDevice(getContext(), &common.ID{Id: deviceID})
 			if verificationFunction(device) {
 				ch <- 1
 				break
 			}
 			if done {
 				break
 			}
 			time.Sleep(retryInterval)
 		}
 	}()
 	timer := time.NewTimer(timeout)
 	defer timer.Stop()
 	select {
 	case <-ch:
 		return nil
 	case <-timer.C:
 		done = true
 		return fmt.Errorf("expected-states-not-reached-for-device%s", deviceID)
 	}
 }

 func waitUntilDevicePortsReadiness(deviceID string,
 	timeout time.Duration,
 	verificationFunction isDevicePortsConditionSatisfied,
 	nbi voltha.VolthaServiceClient) error {
 	ch := make(chan int, 1)
 	done := false
 	go func() {
 		for {
 			ports, _ := nbi.ListDevicePorts(getContext(), &common.ID{Id: deviceID})
 			if verificationFunction(ports) {
 				ch <- 1
 				break
 			}
 			if done {
 				break
 			}
 			time.Sleep(retryInterval)
 		}
 	}()
 	timer := time.NewTimer(timeout)
 	defer timer.Stop()
 	select {
 	case <-ch:
 		return nil
 	case <-timer.C:
 		done = true
 		return fmt.Errorf("expected-states-not-reached-for-device%s", deviceID)
 	}
 }

 func waitUntilLogicalDeviceReadiness(oltDeviceID string,
 	timeout time.Duration,
 	nbi voltha.VolthaServiceClient,
 	verificationFunction isLogicalDeviceConditionSatisfied,
 ) error {
 	ch := make(chan int, 1)
 	done := false
 	go func() {
 		for {
 			// Get the logical device from the olt device
 			d, _ := nbi.GetDevice(getContext(), &common.ID{Id: oltDeviceID})
 			if d != nil && d.ParentId != "" {
 				ld, _ := nbi.GetLogicalDevice(getContext(), &common.ID{Id: d.ParentId})
 				if verificationFunction(ld) {
 					ch <- 1
 					break
 				}
 				if done {
 					break
 				}
 			} else if d != nil && d.ParentId == "" { // case where logical device deleted
 				if verificationFunction(nil) {
 					ch <- 1
 					break
 				}
 				if done {
 					break
 				}
 			}
 			time.Sleep(retryInterval)
 		}
 	}()
 	timer := time.NewTimer(timeout)
 	defer timer.Stop()
 	select {
 	case <-ch:
 		return nil
 	case <-timer.C:
 		done = true
 		return fmt.Errorf("timeout-waiting-for-logical-device-readiness%s", oltDeviceID)
 	}
 }

 func waitUntilLogicalDevicePortsReadiness(oltDeviceID string,
 	timeout time.Duration,
 	nbi voltha.VolthaServiceClient,
 	verificationFunction isLogicalDevicePortsConditionSatisfied,
 ) error {
 	ch := make(chan int, 1)
 	done := false
 	go func() {
 		for {
 			// Get the logical device from the olt device
 			d, _ := nbi.GetDevice(getContext(), &common.ID{Id: oltDeviceID})
 			if d != nil && d.ParentId != "" {
 				ports, err := nbi.ListLogicalDevicePorts(getContext(), &common.ID{Id: d.ParentId})
 				if err == nil && verificationFunction(ports.Items) {
 					ch <- 1
 					break
 				}
 				if done {
 					break
 				}
 			}
 			time.Sleep(retryInterval)
 		}
 	}()
 	timer := time.NewTimer(timeout)
 	defer timer.Stop()
 	select {
 	case <-ch:
 		return nil
 	case <-timer.C:
 		done = true
 		return fmt.Errorf("timeout-waiting-for-logical-device-readiness%s", oltDeviceID)
 	}
 }

 func waitUntilConditionForDevices(timeout time.Duration, nbi voltha.VolthaServiceClient, verificationFunction isDevicesConditionSatisfied) error {
 	ch := make(chan int, 1)
 	done := false
 	go func() {
 		for {
 			devices, _ := nbi.ListDevices(getContext(), &empty.Empty{})
 			if verificationFunction(devices) {
 				ch <- 1
 				break
 			}
 			if done {
 				break
 			}

 			time.Sleep(retryInterval)
 		}
 	}()
 	timer := time.NewTimer(timeout)
 	defer timer.Stop()
 	select {
 	case <-ch:
 		return nil
 	case <-timer.C:
 		done = true
 		return fmt.Errorf("timeout-waiting-devices")
 	}
 }

 func waitUntilConditionForLogicalDevices(timeout time.Duration, nbi voltha.VolthaServiceClient, verificationFunction isLogicalDevicesConditionSatisfied) error {
 	ch := make(chan int, 1)
 	done := false
 	go func() {
 		for {
 			lDevices, _ := nbi.ListLogicalDevices(getContext(), &empty.Empty{})
 			if verificationFunction(lDevices) {
 				ch <- 1
 				break
 			}
 			if done {
 				break
 			}

 			time.Sleep(retryInterval)
 		}
 	}()
 	timer := time.NewTimer(timeout)
 	defer timer.Stop()
 	select {
 	case <-ch:
 		return nil
 	case <-timer.C:
 		done = true
 		return fmt.Errorf("timeout-waiting-logical-devices")
 	}
 }

 func waitUntilCondition(timeout time.Duration, verificationFunction isConditionSatisfied) error {
 	ch := make(chan int, 1)
 	done := false
 	go func() {
 		for {
 			if verificationFunction() {
 				ch <- 1
 				break
 			}
 			if done {
 				break
 			}
 			time.Sleep(retryInterval)
 		}
 	}()
 	timer := time.NewTimer(timeout)
 	defer timer.Stop()
 	select {
 	case <-ch:
 		return nil
 	case <-timer.C:
 		done = true
 		return fmt.Errorf("timeout-waiting-for-condition")
 	}
 }

 func waitUntilDeviceIsRemoved(timeout time.Duration, nbi voltha.VolthaServiceClient, deviceID string) error {
 	ch := make(chan int, 1)
 	done := false
 	go func() {
 		for {
 			_, err := nbi.GetDevice(getContext(), &common.ID{Id: deviceID})
 			if err != nil && strings.Contains(err.Error(), "NotFound") {
 				ch <- 1
 				break
 			}
 			if done {
 				break
 			}
 			time.Sleep(retryInterval)
 		}
 	}()
 	timer := time.NewTimer(timeout)
 	defer timer.Stop()
 	select {
 	case <-ch:
 		return nil
 	case <-timer.C:
 		done = true
 		return fmt.Errorf("timeout-waiting-for-condition")
 	}
 }

 func cleanUpCreatedDevice(timeout time.Duration, nbi voltha.VolthaServiceClient, deviceID string) error {
 	logger.Warnw(context.Background(), "cleanUpCreatedDevice", log.Fields{"device-id": deviceID})
 	ch := make(chan int, 1)
 	done := false
 	go func() {
 		//Force Remove the device - use a loop in case the initial delete fails
 		for {
 			logger.Debugw(context.Background(), "sending delete force ", log.Fields{"device-id": deviceID})
 			var err error
 			if _, err = nbi.ForceDeleteDevice(getContext(), &common.ID{Id: deviceID}); err != nil {
 				logger.Debugw(context.Background(), "delete failed", log.Fields{"device-id": deviceID, "error": err})
 				if strings.Contains(err.Error(), "NotFound") {
 					logger.Debugw(context.Background(), "delete not found", log.Fields{"device-id": deviceID, "error": err})
 					//ch <- 1
 					break
 				}
 				time.Sleep(retryInterval)
 				continue
 			}
 			logger.Debugw(context.Background(), "delete force no error", log.Fields{"device-id": deviceID, "error": err})
 			break
 		}
 		logger.Debugw(context.Background(), "delete sent", log.Fields{"device-id": deviceID})
 		for {
 			_, err := nbi.GetDevice(getContext(), &common.ID{Id: deviceID})
 			if err != nil && strings.Contains(err.Error(), "NotFound") {
 				ch <- 1
 				break
 			}
 			if done {
 				break
 			}
 			time.Sleep(retryInterval)
 		}
 	}()
 	timer := time.NewTimer(timeout)
 	defer timer.Stop()
 	select {
 	case <-ch:
 		return nil
 	case <-timer.C:
 		done = true
 		return fmt.Errorf("timeout-waiting-devices-cleanup")
 	}
 }

 func cleanUpCreatedDevices(timeout time.Duration, nbi voltha.VolthaServiceClient, parentDeviceID string) error {
 	ch := make(chan int, 1)
 	done := false
 	go func() {
 		//Force Remove the device - use a loop in case the initial delete fails
 		for {
 			if _, err := nbi.ForceDeleteDevice(getContext(), &common.ID{Id: parentDeviceID}); err != nil {
 				if strings.Contains(err.Error(), "NotFound") {
 					ch <- 1
 					break
 				}
 				time.Sleep(retryInterval)
 				continue
 			}
 			break
 		}
 		for {
 			devices, _ := nbi.ListDevices(getContext(), &empty.Empty{})
 			removed := devices == nil || len(devices.Items) == 0
 			if !removed {
 				removed = true
 				for _, d := range devices.Items {
 					if (d.Root && d.Id == parentDeviceID) || (!d.Root && d.ParentId == parentDeviceID) {
 						removed = false
 						break
 					}
 				}
 			}
 			if removed {
 				ch <- 1
 				break
 			}
 			if done {
 				break
 			}
 			time.Sleep(retryInterval)
 		}
 	}()
 	timer := time.NewTimer(timeout)
 	defer timer.Stop()
 	select {
 	case <-ch:
 		return nil
 	case <-timer.C:
 		done = true
 		return fmt.Errorf("timeout-waiting-devices-cleanup")
 	}
 }

 func cleanUpDevices(timeout time.Duration, nbi voltha.VolthaServiceClient, parentDeviceID string, verifyParentDeletionOnly bool) error {
 	ch := make(chan int, 1)
 	done := false
 	go func() {
 		// Send a force delete to the parent device
 		for {
 			_, err := nbi.ForceDeleteDevice(getContext(), &common.ID{Id: parentDeviceID})
 			if err == nil || strings.Contains(err.Error(), "NotFound") {
 				break
 			}
 			time.Sleep(retryInterval)
 			if done {
 				return
 			}
 		}
 		var err error
 		for {
 			if verifyParentDeletionOnly {
 				_, err = nbi.GetDevice(getContext(), &common.ID{Id: parentDeviceID})
 				if err != nil && strings.Contains(err.Error(), "NotFound") {
 					ch <- 1
 					break
 				}
 				time.Sleep(retryInterval)
 				if done {
 					return
 				}
 				continue
 			}
 			// verifyParentDeletionOnly is False => check children as well
 			devices, _ := nbi.ListDevices(getContext(), &empty.Empty{})
 			removed := devices == nil || len(devices.Items) == 0
 			if !removed {
 				removed = true
 				for _, d := range devices.Items {
 					if (d.Root && d.Id == parentDeviceID) || (!d.Root && d.ParentId == parentDeviceID) {
 						removed = false
 						break
 					}
 				}
 			}
 			if removed {
 				ch <- 1
 				break
 			}
 			time.Sleep(retryInterval)
 			if done {
 				break
 			}
 		}
 	}()
 	timer := time.NewTimer(timeout)
 	defer timer.Stop()
 	select {
 	case <-ch:
 		return nil
 	case <-timer.C:
 		done = true
 		return fmt.Errorf("timeout-waiting-devices-cleanup")
 	}
 }

 type ChangedEventListener struct {
 	eventSubscriber   chan chan *ofp.ChangeEvent
 	eventUnSubscriber chan chan *ofp.ChangeEvent
 }

 func NewChangedEventListener(bufferSize int) *ChangedEventListener {
 	return &ChangedEventListener{
 		eventSubscriber:   make(chan chan *ofp.ChangeEvent, bufferSize),
 		eventUnSubscriber: make(chan chan *ofp.ChangeEvent, bufferSize),
 	}
 }

 func (cel *ChangedEventListener) Start(ctx context.Context, coreEventsCh chan *ofp.ChangeEvent) {
 	subs := map[chan *ofp.ChangeEvent]struct{}{}
 	var subsLock sync.RWMutex
 	for {
 		select {
 		case <-ctx.Done():
 			logger.Debug(ctx, "closing-change-event-listener")
 			subsLock.RLock()
 			for msgCh := range subs {
 				close(msgCh)
 			}
 			subsLock.RUnlock()
 			return
 		case eventCh := <-cel.eventSubscriber:
 			subsLock.Lock()
 			subs[eventCh] = struct{}{}
 			subsLock.Unlock()
 		case eventCh := <-cel.eventUnSubscriber:
 			subsLock.Lock()
 			close(eventCh)
 			delete(subs, eventCh)
 			subsLock.Unlock()
 		case event := <-coreEventsCh:
 			subsLock.RLock()
 			for subscriber := range subs {
 				select {
 				case subscriber <- event:
 				default:
 				}
 			}
 			subsLock.RUnlock()
 		}
 	}
 }

 func (cel *ChangedEventListener) Subscribe(bufferSize int) chan *ofp.ChangeEvent {
 	eventCh := make(chan *ofp.ChangeEvent, bufferSize)
 	cel.eventSubscriber <- eventCh
 	return eventCh
 }

 func (cel *ChangedEventListener) Unsubscribe(eventCh chan *ofp.ChangeEvent) {
 	cel.eventUnSubscriber <- eventCh
 }
	/*
	* Copyright 2019-present Open Networking Foundation
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/
	package test

	import (
	"context"
	"fmt"
	"strings"
	"sync"
	"time"

	"github.com/opencord/voltha-lib-go/v7/pkg/log"
	"github.com/opencord/voltha-protos/v5/go/common"
	ofp "github.com/opencord/voltha-protos/v5/go/openflow_13"

	"github.com/golang/protobuf/ptypes/empty"
	"github.com/opencord/voltha-protos/v5/go/voltha"
	)

	var retryInterval = 50 * time.Millisecond

	type isLogicalDeviceConditionSatisfied func(ld *voltha.LogicalDevice) bool
	type isLogicalDevicePortsConditionSatisfied func(ports []*voltha.LogicalPort) bool
	type isDeviceConditionSatisfied func(ld *voltha.Device) bool
	type isDevicePortsConditionSatisfied func(ports *voltha.Ports) bool
	type isDevicesConditionSatisfied func(ds *voltha.Devices) bool
	type isLogicalDevicesConditionSatisfied func(lds *voltha.LogicalDevices) bool
	type isConditionSatisfied func() bool

	func getContext() context.Context {
	return context.Background()
	}

	func setRetryInterval(interval time.Duration) {
	retryInterval = interval
	}

	func waitUntilDeviceReadiness(deviceID string,
	timeout time.Duration,
	verificationFunction isDeviceConditionSatisfied,
	nbi voltha.VolthaServiceClient) error {
	ch := make(chan int, 1)
	done := false
	go func() {
	for {
	device, _ := nbi.GetDevice(getContext(), &common.ID{Id: deviceID})
	if verificationFunction(device) {
	ch <- 1
	break
	}
	if done {
	break
	}
	time.Sleep(retryInterval)
	}
	}()
	timer := time.NewTimer(timeout)
	defer timer.Stop()
	select {
	case <-ch:
	return nil
	case <-timer.C:
	done = true
	return fmt.Errorf("expected-states-not-reached-for-device%s", deviceID)
	}
	}

	func waitUntilDevicePortsReadiness(deviceID string,
	timeout time.Duration,
	verificationFunction isDevicePortsConditionSatisfied,
	nbi voltha.VolthaServiceClient) error {
	ch := make(chan int, 1)
	done := false
	go func() {
	for {
	ports, _ := nbi.ListDevicePorts(getContext(), &common.ID{Id: deviceID})
	if verificationFunction(ports) {
	ch <- 1
	break
	}
	if done {
	break
	}
	time.Sleep(retryInterval)
	}
	}()
	timer := time.NewTimer(timeout)
	defer timer.Stop()
	select {
	case <-ch:
	return nil
	case <-timer.C:
	done = true
	return fmt.Errorf("expected-states-not-reached-for-device%s", deviceID)
	}
	}

	func waitUntilLogicalDeviceReadiness(oltDeviceID string,
	timeout time.Duration,
	nbi voltha.VolthaServiceClient,
	verificationFunction isLogicalDeviceConditionSatisfied,
	) error {
	ch := make(chan int, 1)
	done := false
	go func() {
	for {
	// Get the logical device from the olt device
	d, _ := nbi.GetDevice(getContext(), &common.ID{Id: oltDeviceID})
	if d != nil && d.ParentId != "" {
	ld, _ := nbi.GetLogicalDevice(getContext(), &common.ID{Id: d.ParentId})
	if verificationFunction(ld) {
	ch <- 1
	break
	}
	if done {
	break
	}
	} else if d != nil && d.ParentId == "" { // case where logical device deleted
	if verificationFunction(nil) {
	ch <- 1
	break
	}
	if done {
	break
	}
	}
	time.Sleep(retryInterval)
	}
	}()
	timer := time.NewTimer(timeout)
	defer timer.Stop()
	select {
	case <-ch:
	return nil
	case <-timer.C:
	done = true
	return fmt.Errorf("timeout-waiting-for-logical-device-readiness%s", oltDeviceID)
	}
	}

	func waitUntilLogicalDevicePortsReadiness(oltDeviceID string,
	timeout time.Duration,
	nbi voltha.VolthaServiceClient,
	verificationFunction isLogicalDevicePortsConditionSatisfied,
	) error {
	ch := make(chan int, 1)
	done := false
	go func() {
	for {
	// Get the logical device from the olt device
	d, _ := nbi.GetDevice(getContext(), &common.ID{Id: oltDeviceID})
	if d != nil && d.ParentId != "" {
	ports, err := nbi.ListLogicalDevicePorts(getContext(), &common.ID{Id: d.ParentId})
	if err == nil && verificationFunction(ports.Items) {
	ch <- 1
	break
	}
	if done {
	break
	}
	}
	time.Sleep(retryInterval)
	}
	}()
	timer := time.NewTimer(timeout)
	defer timer.Stop()
	select {
	case <-ch:
	return nil
	case <-timer.C:
	done = true
	return fmt.Errorf("timeout-waiting-for-logical-device-readiness%s", oltDeviceID)
	}
	}

	func waitUntilConditionForDevices(timeout time.Duration, nbi voltha.VolthaServiceClient, verificationFunction isDevicesConditionSatisfied) error {
	ch := make(chan int, 1)
	done := false
	go func() {
	for {
	devices, _ := nbi.ListDevices(getContext(), &empty.Empty{})
	if verificationFunction(devices) {
	ch <- 1
	break
	}
	if done {
	break
	}

	time.Sleep(retryInterval)
	}
	}()
	timer := time.NewTimer(timeout)
	defer timer.Stop()
	select {
	case <-ch:
	return nil
	case <-timer.C:
	done = true
	return fmt.Errorf("timeout-waiting-devices")
	}
	}

	func waitUntilConditionForLogicalDevices(timeout time.Duration, nbi voltha.VolthaServiceClient, verificationFunction isLogicalDevicesConditionSatisfied) error {
	ch := make(chan int, 1)
	done := false
	go func() {
	for {
	lDevices, _ := nbi.ListLogicalDevices(getContext(), &empty.Empty{})
	if verificationFunction(lDevices) {
	ch <- 1
	break
	}
	if done {
	break
	}

	time.Sleep(retryInterval)
	}
	}()
	timer := time.NewTimer(timeout)
	defer timer.Stop()
	select {
	case <-ch:
	return nil
	case <-timer.C:
	done = true
	return fmt.Errorf("timeout-waiting-logical-devices")
	}
	}

	func waitUntilCondition(timeout time.Duration, verificationFunction isConditionSatisfied) error {
	ch := make(chan int, 1)
	done := false
	go func() {
	for {
	if verificationFunction() {
	ch <- 1
	break
	}
	if done {
	break
	}
	time.Sleep(retryInterval)
	}
	}()
	timer := time.NewTimer(timeout)
	defer timer.Stop()
	select {
	case <-ch:
	return nil
	case <-timer.C:
	done = true
	return fmt.Errorf("timeout-waiting-for-condition")
	}
	}

	func waitUntilDeviceIsRemoved(timeout time.Duration, nbi voltha.VolthaServiceClient, deviceID string) error {
	ch := make(chan int, 1)
	done := false
	go func() {
	for {
	_, err := nbi.GetDevice(getContext(), &common.ID{Id: deviceID})
	if err != nil && strings.Contains(err.Error(), "NotFound") {
	ch <- 1
	break
	}
	if done {
	break
	}
	time.Sleep(retryInterval)
	}
	}()
	timer := time.NewTimer(timeout)
	defer timer.Stop()
	select {
	case <-ch:
	return nil
	case <-timer.C:
	done = true
	return fmt.Errorf("timeout-waiting-for-condition")
	}
	}

	func cleanUpCreatedDevice(timeout time.Duration, nbi voltha.VolthaServiceClient, deviceID string) error {
	logger.Warnw(context.Background(), "cleanUpCreatedDevice", log.Fields{"device-id": deviceID})
	ch := make(chan int, 1)
	done := false
	go func() {
	//Force Remove the device - use a loop in case the initial delete fails
	for {
	logger.Debugw(context.Background(), "sending delete force ", log.Fields{"device-id": deviceID})
	var err error
	if _, err = nbi.ForceDeleteDevice(getContext(), &common.ID{Id: deviceID}); err != nil {
	logger.Debugw(context.Background(), "delete failed", log.Fields{"device-id": deviceID, "error": err})
	if strings.Contains(err.Error(), "NotFound") {
	logger.Debugw(context.Background(), "delete not found", log.Fields{"device-id": deviceID, "error": err})
	//ch <- 1
	break
	}
	time.Sleep(retryInterval)
	continue
	}
	logger.Debugw(context.Background(), "delete force no error", log.Fields{"device-id": deviceID, "error": err})
	break
	}
	logger.Debugw(context.Background(), "delete sent", log.Fields{"device-id": deviceID})
	for {
	_, err := nbi.GetDevice(getContext(), &common.ID{Id: deviceID})
	if err != nil && strings.Contains(err.Error(), "NotFound") {
	ch <- 1
	break
	}
	if done {
	break
	}
	time.Sleep(retryInterval)
	}
	}()
	timer := time.NewTimer(timeout)
	defer timer.Stop()
	select {
	case <-ch:
	return nil
	case <-timer.C:
	done = true
	return fmt.Errorf("timeout-waiting-devices-cleanup")
	}
	}

	func cleanUpCreatedDevices(timeout time.Duration, nbi voltha.VolthaServiceClient, parentDeviceID string) error {
	ch := make(chan int, 1)
	done := false
	go func() {
	//Force Remove the device - use a loop in case the initial delete fails
	for {
	if _, err := nbi.ForceDeleteDevice(getContext(), &common.ID{Id: parentDeviceID}); err != nil {
	if strings.Contains(err.Error(), "NotFound") {
	ch <- 1
	break
	}
	time.Sleep(retryInterval)
	continue
	}
	break
	}
	for {
	devices, _ := nbi.ListDevices(getContext(), &empty.Empty{})
	removed := devices == nil \|\| len(devices.Items) == 0
	if !removed {
	removed = true
	for _, d := range devices.Items {
	if (d.Root && d.Id == parentDeviceID) \|\| (!d.Root && d.ParentId == parentDeviceID) {
	removed = false
	break
	}
	}
	}
	if removed {
	ch <- 1
	break
	}
	if done {
	break
	}
	time.Sleep(retryInterval)
	}
	}()
	timer := time.NewTimer(timeout)
	defer timer.Stop()
	select {
	case <-ch:
	return nil
	case <-timer.C:
	done = true
	return fmt.Errorf("timeout-waiting-devices-cleanup")
	}
	}

	func cleanUpDevices(timeout time.Duration, nbi voltha.VolthaServiceClient, parentDeviceID string, verifyParentDeletionOnly bool) error {
	ch := make(chan int, 1)
	done := false
	go func() {
	// Send a force delete to the parent device
	for {
	_, err := nbi.ForceDeleteDevice(getContext(), &common.ID{Id: parentDeviceID})
	if err == nil \|\| strings.Contains(err.Error(), "NotFound") {
	break
	}
	time.Sleep(retryInterval)
	if done {
	return
	}
	}
	var err error
	for {
	if verifyParentDeletionOnly {
	_, err = nbi.GetDevice(getContext(), &common.ID{Id: parentDeviceID})
	if err != nil && strings.Contains(err.Error(), "NotFound") {
	ch <- 1
	break
	}
	time.Sleep(retryInterval)
	if done {
	return
	}
	continue
	}
	// verifyParentDeletionOnly is False => check children as well
	devices, _ := nbi.ListDevices(getContext(), &empty.Empty{})
	removed := devices == nil \|\| len(devices.Items) == 0
	if !removed {
	removed = true
	for _, d := range devices.Items {
	if (d.Root && d.Id == parentDeviceID) \|\| (!d.Root && d.ParentId == parentDeviceID) {
	removed = false
	break
	}
	}
	}
	if removed {
	ch <- 1
	break
	}
	time.Sleep(retryInterval)
	if done {
	break
	}
	}
	}()
	timer := time.NewTimer(timeout)
	defer timer.Stop()
	select {
	case <-ch:
	return nil
	case <-timer.C:
	done = true
	return fmt.Errorf("timeout-waiting-devices-cleanup")
	}
	}

	type ChangedEventListener struct {
	eventSubscriber chan chan *ofp.ChangeEvent
	eventUnSubscriber chan chan *ofp.ChangeEvent
	}

	func NewChangedEventListener(bufferSize int) *ChangedEventListener {
	return &ChangedEventListener{
	eventSubscriber: make(chan chan *ofp.ChangeEvent, bufferSize),
	eventUnSubscriber: make(chan chan *ofp.ChangeEvent, bufferSize),
	}
	}

	func (cel ChangedEventListener) Start(ctx context.Context, coreEventsCh chan ofp.ChangeEvent) {
	subs := map[chan *ofp.ChangeEvent]struct{}{}
	var subsLock sync.RWMutex
	for {
	select {
	case <-ctx.Done():
	logger.Debug(ctx, "closing-change-event-listener")
	subsLock.RLock()
	for msgCh := range subs {
	close(msgCh)
	}
	subsLock.RUnlock()
	return
	case eventCh := <-cel.eventSubscriber:
	subsLock.Lock()
	subs[eventCh] = struct{}{}
	subsLock.Unlock()
	case eventCh := <-cel.eventUnSubscriber:
	subsLock.Lock()
	close(eventCh)
	delete(subs, eventCh)
	subsLock.Unlock()
	case event := <-coreEventsCh:
	subsLock.RLock()
	for subscriber := range subs {
	select {
	case subscriber <- event:
	default:
	}
	}
	subsLock.RUnlock()
	}
	}
	}

	func (cel ChangedEventListener) Subscribe(bufferSize int) chan ofp.ChangeEvent {
	eventCh := make(chan *ofp.ChangeEvent, bufferSize)
	cel.eventSubscriber <- eventCh
	return eventCh
	}

	func (cel ChangedEventListener) Unsubscribe(eventCh chan ofp.ChangeEvent) {
	cel.eventUnSubscriber <- eventCh
	}