pkg/control/control.go

/*
==================================================================================
  Copyright (c) 2019 AT&T Intellectual Property.
  Copyright (c) 2019 Nokia

   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 control

import (
	"fmt"
	"gerrit.o-ran-sc.org/r/ric-plt/e2ap/pkg/e2ap"
	rtmgrclient "gerrit.o-ran-sc.org/r/ric-plt/submgr/pkg/rtmgr_client"
	"gerrit.o-ran-sc.org/r/ric-plt/xapp-frame/pkg/models"
	"gerrit.o-ran-sc.org/r/ric-plt/xapp-frame/pkg/xapp"
	httptransport "github.com/go-openapi/runtime/client"
	"github.com/go-openapi/strfmt"
	"github.com/spf13/viper"
	"time"
)

//-----------------------------------------------------------------------------
//
//-----------------------------------------------------------------------------

func idstring(err error, entries ...fmt.Stringer) string {
	var retval string = ""
	var filler string = ""
	for _, entry := range entries {
		retval += filler + entry.String()
		filler = " "
	}
	if err != nil {
		retval += filler + "err(" + err.Error() + ")"
		filler = " "

	}
	return retval
}

//-----------------------------------------------------------------------------
//
//-----------------------------------------------------------------------------

var e2tSubReqTimeout time.Duration
var e2tSubDelReqTime time.Duration
var e2tRecvMsgTimeout time.Duration
var e2tMaxSubReqTryCount uint64    // Initial try + retry
var e2tMaxSubDelReqTryCount uint64 // Initial try + retry

type Control struct {
	*xapp.RMRClient
	e2ap     *E2ap
	registry *Registry
	tracker  *Tracker
	//subscriber *xapp.Subscriber
	CntRecvMsg uint64
}

type RMRMeid struct {
	PlmnID  string
	EnbID   string
	RanName string
}

func init() {
	xapp.Logger.Info("SUBMGR")
	viper.AutomaticEnv()
	viper.SetEnvPrefix("submgr")
	viper.AllowEmptyEnv(true)
}

func NewControl() *Control {

	// viper.GetDuration returns nanoseconds
	e2tSubReqTimeout = viper.GetDuration("controls.e2tSubReqTimeout_ms") * 1000000
	xapp.Logger.Info("e2tSubReqTimeout %v", e2tSubReqTimeout)
	e2tSubDelReqTime = viper.GetDuration("controls.e2tSubDelReqTime_ms") * 1000000
	xapp.Logger.Info("e2tSubDelReqTime %v", e2tSubDelReqTime)
	e2tRecvMsgTimeout = viper.GetDuration("controls.e2tRecvMsgTimeout_ms") * 1000000
	xapp.Logger.Info("e2tRecvMsgTimeout %v", e2tRecvMsgTimeout)
	e2tMaxSubReqTryCount = viper.GetUint64("controls.e2tMaxSubReqTryCount")
	xapp.Logger.Info("e2tMaxSubReqTryCount %v", e2tMaxSubReqTryCount)
	e2tMaxSubDelReqTryCount = viper.GetUint64("controls.e2tMaxSubDelReqTryCount")
	xapp.Logger.Info("e2tMaxSubDelReqTryCount %v", e2tMaxSubDelReqTryCount)

	transport := httptransport.New(viper.GetString("rtmgr.HostAddr")+":"+viper.GetString("rtmgr.port"), viper.GetString("rtmgr.baseUrl"), []string{"http"})
	rtmgrClient := RtmgrClient{rtClient: rtmgrclient.New(transport, strfmt.Default)}

	registry := new(Registry)
	registry.Initialize()
	registry.rtmgrClient = &rtmgrClient

	tracker := new(Tracker)
	tracker.Init()

	//subscriber := xapp.NewSubscriber(viper.GetString("subscription.host"), viper.GetInt("subscription.timeout"))

	c := &Control{e2ap: new(E2ap),
		registry: registry,
		tracker:  tracker,
		//subscriber: subscriber,
	}
	go xapp.Subscription.Listen(c.SubscriptionHandler, c.QueryHandler, c.SubscriptionDeleteHandler)
	//go c.subscriber.Listen(c.SubscriptionHandler, c.QueryHandler)
	return c
}

func (c *Control) ReadyCB(data interface{}) {
	if c.RMRClient == nil {
		c.RMRClient = xapp.Rmr
	}
}

func (c *Control) Run() {
	xapp.SetReadyCB(c.ReadyCB, nil)
	xapp.Run(c)
}

//-------------------------------------------------------------------
//
//-------------------------------------------------------------------
func (c *Control) SubscriptionHandler(stype models.SubscriptionType, params interface{}) (*models.SubscriptionResponse, error) {
	/*
	   switch p := params.(type) {
	   case *models.ReportParams:
	       trans := c.tracker.NewXappTransaction(NewRmrEndpoint(p.ClientEndpoint),"" , 0, &xapp.RMRMeid{RanName: p.Meid})
	       if trans == nil {
	             xapp.Logger.Error("XAPP-SubReq: %s", idstring(fmt.Errorf("transaction not created"), params))
	             return
	       }
	       defer trans.Release()
	   case *models.ControlParams:
	   case *models.PolicyParams:
	   }
	*/
	return &models.SubscriptionResponse{}, fmt.Errorf("Subscription rest interface not implemented")
}

func (c *Control) SubscriptionDeleteHandler(string) error {
	return fmt.Errorf("Subscription rest interface not implemented")
}

func (c *Control) QueryHandler() (models.SubscriptionList, error) {
	return c.registry.QueryHandler()
}

//-------------------------------------------------------------------
//
//-------------------------------------------------------------------

func (c *Control) rmrSendToE2T(desc string, subs *Subscription, trans *TransactionSubs) (err error) {
	params := &xapp.RMRParams{}
	params.Mtype = trans.GetMtype()
	params.SubId = int(subs.GetReqId().InstanceId)
	params.Xid = ""
	params.Meid = subs.GetMeid()
	params.Src = ""
	params.PayloadLen = len(trans.Payload.Buf)
	params.Payload = trans.Payload.Buf
	params.Mbuf = nil
	xapp.Logger.Info("MSG to E2T: %s %s %s", desc, trans.String(), params.String())
	return c.SendWithRetry(params, false, 5)
}

func (c *Control) rmrSendToXapp(desc string, subs *Subscription, trans *TransactionXapp) (err error) {

	params := &xapp.RMRParams{}
	params.Mtype = trans.GetMtype()
	params.SubId = int(subs.GetReqId().InstanceId)
	params.Xid = trans.GetXid()
	params.Meid = trans.GetMeid()
	params.Src = ""
	params.PayloadLen = len(trans.Payload.Buf)
	params.Payload = trans.Payload.Buf
	params.Mbuf = nil
	xapp.Logger.Info("MSG to XAPP: %s %s %s", desc, trans.String(), params.String())
	return c.SendWithRetry(params, false, 5)
}

func (c *Control) Consume(msg *xapp.RMRParams) (err error) {
	if c.RMRClient == nil {
		err = fmt.Errorf("Rmr object nil can handle %s", msg.String())
		xapp.Logger.Error("%s", err.Error())
		return
	}
	c.CntRecvMsg++

	defer c.RMRClient.Free(msg.Mbuf)

	// xapp-frame might use direct access to c buffer and
	// when msg.Mbuf is freed, someone might take it into use
	// and payload data might be invalid inside message handle function
	//
	// subscriptions won't load system a lot so there is no
	// real performance hit by cloning buffer into new go byte slice
	cPay := append(msg.Payload[:0:0], msg.Payload...)
	msg.Payload = cPay
	msg.PayloadLen = len(cPay)

	switch msg.Mtype {
	case xapp.RIC_SUB_REQ:
		go c.handleXAPPSubscriptionRequest(msg)
	case xapp.RIC_SUB_RESP:
		go c.handleE2TSubscriptionResponse(msg)
	case xapp.RIC_SUB_FAILURE:
		go c.handleE2TSubscriptionFailure(msg)
	case xapp.RIC_SUB_DEL_REQ:
		go c.handleXAPPSubscriptionDeleteRequest(msg)
	case xapp.RIC_SUB_DEL_RESP:
		go c.handleE2TSubscriptionDeleteResponse(msg)
	case xapp.RIC_SUB_DEL_FAILURE:
		go c.handleE2TSubscriptionDeleteFailure(msg)
	default:
		xapp.Logger.Info("Unknown Message Type '%d', discarding", msg.Mtype)
	}
	return
}

//-------------------------------------------------------------------
// handle from XAPP Subscription Request
//------------------------------------------------------------------
func (c *Control) handleXAPPSubscriptionRequest(params *xapp.RMRParams) {
	xapp.Logger.Info("MSG from XAPP: %s", params.String())

	subReqMsg, err := c.e2ap.UnpackSubscriptionRequest(params.Payload)
	if err != nil {
		xapp.Logger.Error("XAPP-SubReq: %s", idstring(err, params))
		return
	}

	trans := c.tracker.NewXappTransaction(xapp.NewRmrEndpoint(params.Src), params.Xid, subReqMsg.RequestId.InstanceId, params.Meid)
	if trans == nil {
		xapp.Logger.Error("XAPP-SubReq: %s", idstring(fmt.Errorf("transaction not created"), params))
		return
	}
	defer trans.Release()

	err = c.tracker.Track(trans)
	if err != nil {
		xapp.Logger.Error("XAPP-SubReq: %s", idstring(err, trans))
		return
	}

	//TODO handle subscription toward e2term inside AssignToSubscription / hide handleSubscriptionCreate in it?
	subs, err := c.registry.AssignToSubscription(trans, subReqMsg)
	if err != nil {
		xapp.Logger.Error("XAPP-SubReq: %s", idstring(err, trans))
		return
	}

	//
	// Wake subs request
	//
	go c.handleSubscriptionCreate(subs, trans)
	event, _ := trans.WaitEvent(0) //blocked wait as timeout is handled in subs side

	err = nil
	if event != nil {
		switch themsg := event.(type) {
		case *e2ap.E2APSubscriptionResponse:
			trans.Mtype, trans.Payload, err = c.e2ap.PackSubscriptionResponse(themsg)
			if err == nil {
				trans.Release()
				c.rmrSendToXapp("", subs, trans)
				return
			}
		case *e2ap.E2APSubscriptionFailure:
			trans.Mtype, trans.Payload, err = c.e2ap.PackSubscriptionFailure(themsg)
			if err == nil {
				c.rmrSendToXapp("", subs, trans)
			}
		default:
			break
		}
	}
	xapp.Logger.Info("XAPP-SubReq: failed %s", idstring(err, trans, subs))
	//c.registry.RemoveFromSubscription(subs, trans, 5*time.Second)
}

//-------------------------------------------------------------------
// handle from XAPP Subscription Delete Request
//------------------------------------------------------------------
func (c *Control) handleXAPPSubscriptionDeleteRequest(params *xapp.RMRParams) {
	xapp.Logger.Info("MSG from XAPP: %s", params.String())

	subDelReqMsg, err := c.e2ap.UnpackSubscriptionDeleteRequest(params.Payload)
	if err != nil {
		xapp.Logger.Error("XAPP-SubDelReq %s", idstring(err, params))
		return
	}

	trans := c.tracker.NewXappTransaction(xapp.NewRmrEndpoint(params.Src), params.Xid, subDelReqMsg.RequestId.InstanceId, params.Meid)
	if trans == nil {
		xapp.Logger.Error("XAPP-SubDelReq: %s", idstring(fmt.Errorf("transaction not created"), params))
		return
	}
	defer trans.Release()

	err = c.tracker.Track(trans)
	if err != nil {
		xapp.Logger.Error("XAPP-SubReq: %s", idstring(err, trans))
		return
	}

	subs, err := c.registry.GetSubscriptionFirstMatch([]uint32{trans.GetSubId()})
	if err != nil {
		xapp.Logger.Error("XAPP-SubDelReq: %s", idstring(err, trans))
		return
	}

	//
	// Wake subs delete
	//
	go c.handleSubscriptionDelete(subs, trans)
	trans.WaitEvent(0) //blocked wait as timeout is handled in subs side

	xapp.Logger.Debug("XAPP-SubDelReq: Handling event %s ", idstring(nil, trans, subs))

	// Whatever is received send ok delete response
	subDelRespMsg := &e2ap.E2APSubscriptionDeleteResponse{}
	subDelRespMsg.RequestId = subs.GetReqId().RequestId
	subDelRespMsg.FunctionId = subs.SubReqMsg.FunctionId
	trans.Mtype, trans.Payload, err = c.e2ap.PackSubscriptionDeleteResponse(subDelRespMsg)
	if err == nil {
		c.rmrSendToXapp("", subs, trans)
	}

	//TODO handle subscription toward e2term insiged RemoveFromSubscription / hide handleSubscriptionDelete in it?
	//c.registry.RemoveFromSubscription(subs, trans, 5*time.Second)
}

//-------------------------------------------------------------------
// SUBS CREATE Handling
//-------------------------------------------------------------------
func (c *Control) handleSubscriptionCreate(subs *Subscription, parentTrans *TransactionXapp) {

	trans := c.tracker.NewSubsTransaction(subs)
	subs.WaitTransactionTurn(trans)
	defer subs.ReleaseTransactionTurn(trans)
	defer trans.Release()

	xapp.Logger.Debug("SUBS-SubReq: Handling %s ", idstring(nil, trans, subs, parentTrans))

	subRfMsg, valid := subs.GetCachedResponse()
	if subRfMsg == nil && valid == true {

		//
		// In case of failure
		// - make internal delete
		// - in case duplicate cause, retry (currently max 1 retry)
		//
		maxRetries := uint64(1)
		doRetry := true
		for retries := uint64(0); retries <= maxRetries && doRetry; retries++ {
			doRetry = false

			event := c.sendE2TSubscriptionRequest(subs, trans, parentTrans)
			switch themsg := event.(type) {
			case *e2ap.E2APSubscriptionResponse:
				subRfMsg, valid = subs.SetCachedResponse(event, true)
			case *e2ap.E2APSubscriptionFailure:
				subRfMsg, valid = subs.SetCachedResponse(event, false)
				doRetry = true
				for _, item := range themsg.ActionNotAdmittedList.Items {
					if item.Cause.Content != e2ap.E2AP_CauseContent_Ric || (item.Cause.Value != e2ap.E2AP_CauseValue_Ric_duplicate_action && item.Cause.Value != e2ap.E2AP_CauseValue_Ric_duplicate_event) {
						doRetry = false
						break
					}
				}
				xapp.Logger.Info("SUBS-SubReq: internal delete and possible retry due event(%s) retry(%t,%d/%d) %s", typeofSubsMessage(event), doRetry, retries, maxRetries, idstring(nil, trans, subs, parentTrans))
				c.sendE2TSubscriptionDeleteRequest(subs, trans, parentTrans)
			default:
				xapp.Logger.Info("SUBS-SubReq: internal delete due event(%s) %s", typeofSubsMessage(event), idstring(nil, trans, subs, parentTrans))
				subRfMsg, valid = subs.SetCachedResponse(nil, false)
				c.sendE2TSubscriptionDeleteRequest(subs, trans, parentTrans)
			}
		}

		xapp.Logger.Debug("SUBS-SubReq: Handling (e2t response %s) %s", typeofSubsMessage(subRfMsg), idstring(nil, trans, subs, parentTrans))
	} else {
		xapp.Logger.Debug("SUBS-SubReq: Handling (cached response %s) %s", typeofSubsMessage(subRfMsg), idstring(nil, trans, subs, parentTrans))
	}

	//Now RemoveFromSubscription in here to avoid race conditions (mostly concerns delete)
	if valid == false {
		c.registry.RemoveFromSubscription(subs, parentTrans, 5*time.Second)
	}
	parentTrans.SendEvent(subRfMsg, 0)
}

//-------------------------------------------------------------------
// SUBS DELETE Handling
//-------------------------------------------------------------------

func (c *Control) handleSubscriptionDelete(subs *Subscription, parentTrans *TransactionXapp) {

	trans := c.tracker.NewSubsTransaction(subs)
	subs.WaitTransactionTurn(trans)
	defer subs.ReleaseTransactionTurn(trans)
	defer trans.Release()

	xapp.Logger.Debug("SUBS-SubDelReq: Handling %s", idstring(nil, trans, subs, parentTrans))

	subs.mutex.Lock()
	if subs.valid && subs.EpList.HasEndpoint(parentTrans.GetEndpoint()) && subs.EpList.Size() == 1 {
		subs.valid = false
		subs.mutex.Unlock()
		c.sendE2TSubscriptionDeleteRequest(subs, trans, parentTrans)
	} else {
		subs.mutex.Unlock()
	}
	//Now RemoveFromSubscription in here to avoid race conditions (mostly concerns delete)
	//  If parallel deletes ongoing both might pass earlier sendE2TSubscriptionDeleteRequest(...) if
	//  RemoveFromSubscription locates in caller side (now in handleXAPPSubscriptionDeleteRequest(...))
	c.registry.RemoveFromSubscription(subs, parentTrans, 5*time.Second)
	parentTrans.SendEvent(nil, 0)
}

//-------------------------------------------------------------------
// send to E2T Subscription Request
//-------------------------------------------------------------------
func (c *Control) sendE2TSubscriptionRequest(subs *Subscription, trans *TransactionSubs, parentTrans *TransactionXapp) interface{} {
	var err error
	var event interface{} = nil
	var timedOut bool = false

	subReqMsg := subs.SubReqMsg
	subReqMsg.RequestId = subs.GetReqId().RequestId
	trans.Mtype, trans.Payload, err = c.e2ap.PackSubscriptionRequest(subReqMsg)
	if err != nil {
		xapp.Logger.Error("SUBS-SubReq: %s", idstring(err, trans, subs, parentTrans))
		return event
	}

	for retries := uint64(0); retries < e2tMaxSubReqTryCount; retries++ {
		desc := fmt.Sprintf("(retry %d)", retries)
		c.rmrSendToE2T(desc, subs, trans)
		event, timedOut = trans.WaitEvent(e2tSubReqTimeout)
		if timedOut {
			continue
		}
		break
	}
	xapp.Logger.Debug("SUBS-SubReq: Response handling event(%s) %s", typeofSubsMessage(event), idstring(nil, trans, subs, parentTrans))
	return event
}

//-------------------------------------------------------------------
// send to E2T Subscription Delete Request
//-------------------------------------------------------------------

func (c *Control) sendE2TSubscriptionDeleteRequest(subs *Subscription, trans *TransactionSubs, parentTrans *TransactionXapp) interface{} {
	var err error
	var event interface{}
	var timedOut bool

	subDelReqMsg := &e2ap.E2APSubscriptionDeleteRequest{}
	subDelReqMsg.RequestId = subs.GetReqId().RequestId
	subDelReqMsg.FunctionId = subs.SubReqMsg.FunctionId
	trans.Mtype, trans.Payload, err = c.e2ap.PackSubscriptionDeleteRequest(subDelReqMsg)
	if err != nil {
		xapp.Logger.Error("SUBS-SubDelReq: %s", idstring(err, trans, subs, parentTrans))
		return event
	}

	for retries := uint64(0); retries < e2tMaxSubDelReqTryCount; retries++ {
		desc := fmt.Sprintf("(retry %d)", retries)
		c.rmrSendToE2T(desc, subs, trans)
		event, timedOut = trans.WaitEvent(e2tSubDelReqTime)
		if timedOut {
			continue
		}
		break
	}
	xapp.Logger.Debug("SUBS-SubDelReq: Response handling event(%s) %s", typeofSubsMessage(event), idstring(nil, trans, subs, parentTrans))
	return event
}

//-------------------------------------------------------------------
// handle from E2T Subscription Reponse
//-------------------------------------------------------------------
func (c *Control) handleE2TSubscriptionResponse(params *xapp.RMRParams) {
	xapp.Logger.Info("MSG from E2T: %s", params.String())
	subRespMsg, err := c.e2ap.UnpackSubscriptionResponse(params.Payload)
	if err != nil {
		xapp.Logger.Error("MSG-SubResp %s", idstring(err, params))
		return
	}
	subs, err := c.registry.GetSubscriptionFirstMatch([]uint32{subRespMsg.RequestId.InstanceId})
	if err != nil {
		xapp.Logger.Error("MSG-SubResp: %s", idstring(err, params))
		return
	}
	trans := subs.GetTransaction()
	if trans == nil {
		err = fmt.Errorf("Ongoing transaction not found")
		xapp.Logger.Error("MSG-SubResp: %s", idstring(err, params, subs))
		return
	}
	sendOk, timedOut := trans.SendEvent(subRespMsg, e2tRecvMsgTimeout)
	if sendOk == false {
		err = fmt.Errorf("Passing event to transaction failed: sendOk(%t) timedOut(%t)", sendOk, timedOut)
		xapp.Logger.Error("MSG-SubResp: %s", idstring(err, trans, subs))
	}
	return
}

//-------------------------------------------------------------------
// handle from E2T Subscription Failure
//-------------------------------------------------------------------
func (c *Control) handleE2TSubscriptionFailure(params *xapp.RMRParams) {
	xapp.Logger.Info("MSG from E2T: %s", params.String())
	subFailMsg, err := c.e2ap.UnpackSubscriptionFailure(params.Payload)
	if err != nil {
		xapp.Logger.Error("MSG-SubFail %s", idstring(err, params))
		return
	}
	subs, err := c.registry.GetSubscriptionFirstMatch([]uint32{subFailMsg.RequestId.InstanceId})
	if err != nil {
		xapp.Logger.Error("MSG-SubFail: %s", idstring(err, params))
		return
	}
	trans := subs.GetTransaction()
	if trans == nil {
		err = fmt.Errorf("Ongoing transaction not found")
		xapp.Logger.Error("MSG-SubFail: %s", idstring(err, params, subs))
		return
	}
	sendOk, timedOut := trans.SendEvent(subFailMsg, e2tRecvMsgTimeout)
	if sendOk == false {
		err = fmt.Errorf("Passing event to transaction failed: sendOk(%t) timedOut(%t)", sendOk, timedOut)
		xapp.Logger.Error("MSG-SubFail: %s", idstring(err, trans, subs))
	}
	return
}

//-------------------------------------------------------------------
// handle from E2T Subscription Delete Response
//-------------------------------------------------------------------
func (c *Control) handleE2TSubscriptionDeleteResponse(params *xapp.RMRParams) (err error) {
	xapp.Logger.Info("MSG from E2T: %s", params.String())
	subDelRespMsg, err := c.e2ap.UnpackSubscriptionDeleteResponse(params.Payload)
	if err != nil {
		xapp.Logger.Error("MSG-SubDelResp: %s", idstring(err, params))
		return
	}
	subs, err := c.registry.GetSubscriptionFirstMatch([]uint32{subDelRespMsg.RequestId.InstanceId})
	if err != nil {
		xapp.Logger.Error("MSG-SubDelResp: %s", idstring(err, params))
		return
	}
	trans := subs.GetTransaction()
	if trans == nil {
		err = fmt.Errorf("Ongoing transaction not found")
		xapp.Logger.Error("MSG-SubDelResp: %s", idstring(err, params, subs))
		return
	}
	sendOk, timedOut := trans.SendEvent(subDelRespMsg, e2tRecvMsgTimeout)
	if sendOk == false {
		err = fmt.Errorf("Passing event to transaction failed: sendOk(%t) timedOut(%t)", sendOk, timedOut)
		xapp.Logger.Error("MSG-SubDelResp: %s", idstring(err, trans, subs))
	}
	return
}

//-------------------------------------------------------------------
// handle from E2T Subscription Delete Failure
//-------------------------------------------------------------------
func (c *Control) handleE2TSubscriptionDeleteFailure(params *xapp.RMRParams) {
	xapp.Logger.Info("MSG from E2T: %s", params.String())
	subDelFailMsg, err := c.e2ap.UnpackSubscriptionDeleteFailure(params.Payload)
	if err != nil {
		xapp.Logger.Error("MSG-SubDelFail: %s", idstring(err, params))
		return
	}
	subs, err := c.registry.GetSubscriptionFirstMatch([]uint32{subDelFailMsg.RequestId.InstanceId})
	if err != nil {
		xapp.Logger.Error("MSG-SubDelFail: %s", idstring(err, params))
		return
	}
	trans := subs.GetTransaction()
	if trans == nil {
		err = fmt.Errorf("Ongoing transaction not found")
		xapp.Logger.Error("MSG-SubDelFail: %s", idstring(err, params, subs))
		return
	}
	sendOk, timedOut := trans.SendEvent(subDelFailMsg, e2tRecvMsgTimeout)
	if sendOk == false {
		err = fmt.Errorf("Passing event to transaction failed: sendOk(%t) timedOut(%t)", sendOk, timedOut)
		xapp.Logger.Error("MSG-SubDelFail: %s", idstring(err, trans, subs))
	}
	return
}

//-------------------------------------------------------------------
//
//-------------------------------------------------------------------
func typeofSubsMessage(v interface{}) string {
	if v == nil {
		return "NIL"
	}
	switch v.(type) {
	case *e2ap.E2APSubscriptionRequest:
		return "SubReq"
	case *e2ap.E2APSubscriptionResponse:
		return "SubResp"
	case *e2ap.E2APSubscriptionFailure:
		return "SubFail"
	case *e2ap.E2APSubscriptionDeleteRequest:
		return "SubDelReq"
	case *e2ap.E2APSubscriptionDeleteResponse:
		return "SubDelResp"
	case *e2ap.E2APSubscriptionDeleteFailure:
		return "SubDelFail"
	default:
		return "Unknown"
	}
}