VOL-2153 move flow_utils.go from voltha-go to voltha-lib-go;
release 2.2.6

Based on voltha-go commit ec6e61b6239b955b6e7623ba3b604e8030154773

Change-Id: Id52f3eb1cb4bcade3f0e42da0129b643fdc5b0f9
diff --git a/pkg/flows/flow_utils.go b/pkg/flows/flow_utils.go
new file mode 100644
index 0000000..2dbf52d
--- /dev/null
+++ b/pkg/flows/flow_utils.go
@@ -0,0 +1,1332 @@
+/*
+ * Copyright 2018-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 flows
+
+import (
+	"bytes"
+	"crypto/md5"
+	"fmt"
+	"github.com/cevaris/ordered_map"
+	"github.com/gogo/protobuf/proto"
+	"github.com/opencord/voltha-lib-go/pkg/log"
+	ofp "github.com/opencord/voltha-protos/go/openflow_13"
+	"math/big"
+	"strings"
+)
+
+var (
+	// Instructions shortcut
+	APPLY_ACTIONS  = ofp.OfpInstructionType_OFPIT_APPLY_ACTIONS
+	WRITE_METADATA = ofp.OfpInstructionType_OFPIT_WRITE_METADATA
+	METER_ACTION   = ofp.OfpInstructionType_OFPIT_METER
+
+	//OFPAT_* shortcuts
+	OUTPUT       = ofp.OfpActionType_OFPAT_OUTPUT
+	COPY_TTL_OUT = ofp.OfpActionType_OFPAT_COPY_TTL_OUT
+	COPY_TTL_IN  = ofp.OfpActionType_OFPAT_COPY_TTL_IN
+	SET_MPLS_TTL = ofp.OfpActionType_OFPAT_SET_MPLS_TTL
+	DEC_MPLS_TTL = ofp.OfpActionType_OFPAT_DEC_MPLS_TTL
+	PUSH_VLAN    = ofp.OfpActionType_OFPAT_PUSH_VLAN
+	POP_VLAN     = ofp.OfpActionType_OFPAT_POP_VLAN
+	PUSH_MPLS    = ofp.OfpActionType_OFPAT_PUSH_MPLS
+	POP_MPLS     = ofp.OfpActionType_OFPAT_POP_MPLS
+	SET_QUEUE    = ofp.OfpActionType_OFPAT_SET_QUEUE
+	GROUP        = ofp.OfpActionType_OFPAT_GROUP
+	SET_NW_TTL   = ofp.OfpActionType_OFPAT_SET_NW_TTL
+	NW_TTL       = ofp.OfpActionType_OFPAT_DEC_NW_TTL
+	SET_FIELD    = ofp.OfpActionType_OFPAT_SET_FIELD
+	PUSH_PBB     = ofp.OfpActionType_OFPAT_PUSH_PBB
+	POP_PBB      = ofp.OfpActionType_OFPAT_POP_PBB
+	EXPERIMENTER = ofp.OfpActionType_OFPAT_EXPERIMENTER
+
+	//OFPXMT_OFB_* shortcuts (incomplete)
+	IN_PORT         = ofp.OxmOfbFieldTypes_OFPXMT_OFB_IN_PORT
+	IN_PHY_PORT     = ofp.OxmOfbFieldTypes_OFPXMT_OFB_IN_PHY_PORT
+	METADATA        = ofp.OxmOfbFieldTypes_OFPXMT_OFB_METADATA
+	ETH_DST         = ofp.OxmOfbFieldTypes_OFPXMT_OFB_ETH_DST
+	ETH_SRC         = ofp.OxmOfbFieldTypes_OFPXMT_OFB_ETH_SRC
+	ETH_TYPE        = ofp.OxmOfbFieldTypes_OFPXMT_OFB_ETH_TYPE
+	VLAN_VID        = ofp.OxmOfbFieldTypes_OFPXMT_OFB_VLAN_VID
+	VLAN_PCP        = ofp.OxmOfbFieldTypes_OFPXMT_OFB_VLAN_PCP
+	IP_DSCP         = ofp.OxmOfbFieldTypes_OFPXMT_OFB_IP_DSCP
+	IP_ECN          = ofp.OxmOfbFieldTypes_OFPXMT_OFB_IP_ECN
+	IP_PROTO        = ofp.OxmOfbFieldTypes_OFPXMT_OFB_IP_PROTO
+	IPV4_SRC        = ofp.OxmOfbFieldTypes_OFPXMT_OFB_IPV4_SRC
+	IPV4_DST        = ofp.OxmOfbFieldTypes_OFPXMT_OFB_IPV4_DST
+	TCP_SRC         = ofp.OxmOfbFieldTypes_OFPXMT_OFB_TCP_SRC
+	TCP_DST         = ofp.OxmOfbFieldTypes_OFPXMT_OFB_TCP_DST
+	UDP_SRC         = ofp.OxmOfbFieldTypes_OFPXMT_OFB_UDP_SRC
+	UDP_DST         = ofp.OxmOfbFieldTypes_OFPXMT_OFB_UDP_DST
+	SCTP_SRC        = ofp.OxmOfbFieldTypes_OFPXMT_OFB_SCTP_SRC
+	SCTP_DST        = ofp.OxmOfbFieldTypes_OFPXMT_OFB_SCTP_DST
+	ICMPV4_TYPE     = ofp.OxmOfbFieldTypes_OFPXMT_OFB_ICMPV4_TYPE
+	ICMPV4_CODE     = ofp.OxmOfbFieldTypes_OFPXMT_OFB_ICMPV4_CODE
+	ARP_OP          = ofp.OxmOfbFieldTypes_OFPXMT_OFB_ARP_OP
+	ARP_SPA         = ofp.OxmOfbFieldTypes_OFPXMT_OFB_ARP_SPA
+	ARP_TPA         = ofp.OxmOfbFieldTypes_OFPXMT_OFB_ARP_TPA
+	ARP_SHA         = ofp.OxmOfbFieldTypes_OFPXMT_OFB_ARP_SHA
+	ARP_THA         = ofp.OxmOfbFieldTypes_OFPXMT_OFB_ARP_THA
+	IPV6_SRC        = ofp.OxmOfbFieldTypes_OFPXMT_OFB_IPV6_SRC
+	IPV6_DST        = ofp.OxmOfbFieldTypes_OFPXMT_OFB_IPV6_DST
+	IPV6_FLABEL     = ofp.OxmOfbFieldTypes_OFPXMT_OFB_IPV6_FLABEL
+	ICMPV6_TYPE     = ofp.OxmOfbFieldTypes_OFPXMT_OFB_ICMPV6_TYPE
+	ICMPV6_CODE     = ofp.OxmOfbFieldTypes_OFPXMT_OFB_ICMPV6_CODE
+	IPV6_ND_TARGET  = ofp.OxmOfbFieldTypes_OFPXMT_OFB_IPV6_ND_TARGET
+	OFB_IPV6_ND_SLL = ofp.OxmOfbFieldTypes_OFPXMT_OFB_IPV6_ND_SLL
+	IPV6_ND_TLL     = ofp.OxmOfbFieldTypes_OFPXMT_OFB_IPV6_ND_TLL
+	MPLS_LABEL      = ofp.OxmOfbFieldTypes_OFPXMT_OFB_MPLS_LABEL
+	MPLS_TC         = ofp.OxmOfbFieldTypes_OFPXMT_OFB_MPLS_TC
+	MPLS_BOS        = ofp.OxmOfbFieldTypes_OFPXMT_OFB_MPLS_BOS
+	PBB_ISID        = ofp.OxmOfbFieldTypes_OFPXMT_OFB_PBB_ISID
+	TUNNEL_ID       = ofp.OxmOfbFieldTypes_OFPXMT_OFB_TUNNEL_ID
+	IPV6_EXTHDR     = ofp.OxmOfbFieldTypes_OFPXMT_OFB_IPV6_EXTHDR
+)
+
+//ofp_action_* shortcuts
+
+func Output(port uint32, maxLen ...ofp.OfpControllerMaxLen) *ofp.OfpAction {
+	maxLength := ofp.OfpControllerMaxLen_OFPCML_MAX
+	if len(maxLen) > 0 {
+		maxLength = maxLen[0]
+	}
+	return &ofp.OfpAction{Type: OUTPUT, Action: &ofp.OfpAction_Output{Output: &ofp.OfpActionOutput{Port: port, MaxLen: uint32(maxLength)}}}
+}
+
+func MplsTtl(ttl uint32) *ofp.OfpAction {
+	return &ofp.OfpAction{Type: SET_MPLS_TTL, Action: &ofp.OfpAction_MplsTtl{MplsTtl: &ofp.OfpActionMplsTtl{MplsTtl: ttl}}}
+}
+
+func PushVlan(ethType uint32) *ofp.OfpAction {
+	return &ofp.OfpAction{Type: PUSH_VLAN, Action: &ofp.OfpAction_Push{Push: &ofp.OfpActionPush{Ethertype: ethType}}}
+}
+
+func PopVlan() *ofp.OfpAction {
+	return &ofp.OfpAction{Type: POP_VLAN}
+}
+
+func PopMpls(ethType uint32) *ofp.OfpAction {
+	return &ofp.OfpAction{Type: POP_MPLS, Action: &ofp.OfpAction_PopMpls{PopMpls: &ofp.OfpActionPopMpls{Ethertype: ethType}}}
+}
+
+func Group(groupId uint32) *ofp.OfpAction {
+	return &ofp.OfpAction{Type: GROUP, Action: &ofp.OfpAction_Group{Group: &ofp.OfpActionGroup{GroupId: groupId}}}
+}
+
+func NwTtl(nwTtl uint32) *ofp.OfpAction {
+	return &ofp.OfpAction{Type: NW_TTL, Action: &ofp.OfpAction_NwTtl{NwTtl: &ofp.OfpActionNwTtl{NwTtl: nwTtl}}}
+}
+
+func SetField(field *ofp.OfpOxmOfbField) *ofp.OfpAction {
+	actionSetField := &ofp.OfpOxmField{OxmClass: ofp.OfpOxmClass_OFPXMC_OPENFLOW_BASIC, Field: &ofp.OfpOxmField_OfbField{OfbField: field}}
+	return &ofp.OfpAction{Type: SET_FIELD, Action: &ofp.OfpAction_SetField{SetField: &ofp.OfpActionSetField{Field: actionSetField}}}
+}
+
+func Experimenter(experimenter uint32, data []byte) *ofp.OfpAction {
+	return &ofp.OfpAction{Type: EXPERIMENTER, Action: &ofp.OfpAction_Experimenter{Experimenter: &ofp.OfpActionExperimenter{Experimenter: experimenter, Data: data}}}
+}
+
+//ofb_field generators (incomplete set)
+
+func InPort(inPort uint32) *ofp.OfpOxmOfbField {
+	return &ofp.OfpOxmOfbField{Type: IN_PORT, Value: &ofp.OfpOxmOfbField_Port{Port: inPort}}
+}
+
+func InPhyPort(inPhyPort uint32) *ofp.OfpOxmOfbField {
+	return &ofp.OfpOxmOfbField{Type: IN_PHY_PORT, Value: &ofp.OfpOxmOfbField_Port{Port: inPhyPort}}
+}
+
+func Metadata_ofp(tableMetadata uint64) *ofp.OfpOxmOfbField {
+	return &ofp.OfpOxmOfbField{Type: METADATA, Value: &ofp.OfpOxmOfbField_TableMetadata{TableMetadata: tableMetadata}}
+}
+
+// should Metadata_ofp used here ?????
+func EthDst(ethDst uint64) *ofp.OfpOxmOfbField {
+	return &ofp.OfpOxmOfbField{Type: ETH_DST, Value: &ofp.OfpOxmOfbField_TableMetadata{TableMetadata: ethDst}}
+}
+
+// should Metadata_ofp used here ?????
+func EthSrc(ethSrc uint64) *ofp.OfpOxmOfbField {
+	return &ofp.OfpOxmOfbField{Type: ETH_SRC, Value: &ofp.OfpOxmOfbField_TableMetadata{TableMetadata: ethSrc}}
+}
+
+func EthType(ethType uint32) *ofp.OfpOxmOfbField {
+	return &ofp.OfpOxmOfbField{Type: ETH_TYPE, Value: &ofp.OfpOxmOfbField_EthType{EthType: ethType}}
+}
+
+func VlanVid(vlanVid uint32) *ofp.OfpOxmOfbField {
+	return &ofp.OfpOxmOfbField{Type: VLAN_VID, Value: &ofp.OfpOxmOfbField_VlanVid{VlanVid: vlanVid}}
+}
+
+func VlanPcp(vlanPcp uint32) *ofp.OfpOxmOfbField {
+	return &ofp.OfpOxmOfbField{Type: VLAN_PCP, Value: &ofp.OfpOxmOfbField_VlanPcp{VlanPcp: vlanPcp}}
+}
+
+func IpDscp(ipDscp uint32) *ofp.OfpOxmOfbField {
+	return &ofp.OfpOxmOfbField{Type: IP_DSCP, Value: &ofp.OfpOxmOfbField_IpDscp{IpDscp: ipDscp}}
+}
+
+func IpEcn(ipEcn uint32) *ofp.OfpOxmOfbField {
+	return &ofp.OfpOxmOfbField{Type: IP_ECN, Value: &ofp.OfpOxmOfbField_IpEcn{IpEcn: ipEcn}}
+}
+
+func IpProto(ipProto uint32) *ofp.OfpOxmOfbField {
+	return &ofp.OfpOxmOfbField{Type: IP_PROTO, Value: &ofp.OfpOxmOfbField_IpProto{IpProto: ipProto}}
+}
+
+func Ipv4Src(ipv4Src uint32) *ofp.OfpOxmOfbField {
+	return &ofp.OfpOxmOfbField{Type: IPV4_SRC, Value: &ofp.OfpOxmOfbField_Ipv4Src{Ipv4Src: ipv4Src}}
+}
+
+func Ipv4Dst(ipv4Dst uint32) *ofp.OfpOxmOfbField {
+	return &ofp.OfpOxmOfbField{Type: IPV4_DST, Value: &ofp.OfpOxmOfbField_Ipv4Dst{Ipv4Dst: ipv4Dst}}
+}
+
+func TcpSrc(tcpSrc uint32) *ofp.OfpOxmOfbField {
+	return &ofp.OfpOxmOfbField{Type: TCP_SRC, Value: &ofp.OfpOxmOfbField_TcpSrc{TcpSrc: tcpSrc}}
+}
+
+func TcpDst(tcpDst uint32) *ofp.OfpOxmOfbField {
+	return &ofp.OfpOxmOfbField{Type: TCP_DST, Value: &ofp.OfpOxmOfbField_TcpDst{TcpDst: tcpDst}}
+}
+
+func UdpSrc(udpSrc uint32) *ofp.OfpOxmOfbField {
+	return &ofp.OfpOxmOfbField{Type: UDP_SRC, Value: &ofp.OfpOxmOfbField_UdpSrc{UdpSrc: udpSrc}}
+}
+
+func UdpDst(udpDst uint32) *ofp.OfpOxmOfbField {
+	return &ofp.OfpOxmOfbField{Type: UDP_DST, Value: &ofp.OfpOxmOfbField_UdpDst{UdpDst: udpDst}}
+}
+
+func SctpSrc(sctpSrc uint32) *ofp.OfpOxmOfbField {
+	return &ofp.OfpOxmOfbField{Type: SCTP_SRC, Value: &ofp.OfpOxmOfbField_SctpSrc{SctpSrc: sctpSrc}}
+}
+
+func SctpDst(sctpDst uint32) *ofp.OfpOxmOfbField {
+	return &ofp.OfpOxmOfbField{Type: SCTP_DST, Value: &ofp.OfpOxmOfbField_SctpDst{SctpDst: sctpDst}}
+}
+
+func Icmpv4Type(icmpv4Type uint32) *ofp.OfpOxmOfbField {
+	return &ofp.OfpOxmOfbField{Type: ICMPV4_TYPE, Value: &ofp.OfpOxmOfbField_Icmpv4Type{Icmpv4Type: icmpv4Type}}
+}
+
+func Icmpv4Code(icmpv4Code uint32) *ofp.OfpOxmOfbField {
+	return &ofp.OfpOxmOfbField{Type: ICMPV4_CODE, Value: &ofp.OfpOxmOfbField_Icmpv4Code{Icmpv4Code: icmpv4Code}}
+}
+
+func ArpOp(arpOp uint32) *ofp.OfpOxmOfbField {
+	return &ofp.OfpOxmOfbField{Type: ARP_OP, Value: &ofp.OfpOxmOfbField_ArpOp{ArpOp: arpOp}}
+}
+
+func ArpSpa(arpSpa uint32) *ofp.OfpOxmOfbField {
+	return &ofp.OfpOxmOfbField{Type: ARP_SPA, Value: &ofp.OfpOxmOfbField_ArpSpa{ArpSpa: arpSpa}}
+}
+
+func ArpTpa(arpTpa uint32) *ofp.OfpOxmOfbField {
+	return &ofp.OfpOxmOfbField{Type: ARP_TPA, Value: &ofp.OfpOxmOfbField_ArpTpa{ArpTpa: arpTpa}}
+}
+
+func ArpSha(arpSha []byte) *ofp.OfpOxmOfbField {
+	return &ofp.OfpOxmOfbField{Type: ARP_SHA, Value: &ofp.OfpOxmOfbField_ArpSha{ArpSha: arpSha}}
+}
+
+func ArpTha(arpTha []byte) *ofp.OfpOxmOfbField {
+	return &ofp.OfpOxmOfbField{Type: ARP_THA, Value: &ofp.OfpOxmOfbField_ArpTha{ArpTha: arpTha}}
+}
+
+func Ipv6Src(ipv6Src []byte) *ofp.OfpOxmOfbField {
+	return &ofp.OfpOxmOfbField{Type: IPV6_SRC, Value: &ofp.OfpOxmOfbField_Ipv6Src{Ipv6Src: ipv6Src}}
+}
+
+func Ipv6Dst(ipv6Dst []byte) *ofp.OfpOxmOfbField {
+	return &ofp.OfpOxmOfbField{Type: IPV6_DST, Value: &ofp.OfpOxmOfbField_Ipv6Dst{Ipv6Dst: ipv6Dst}}
+}
+
+func Ipv6Flabel(ipv6Flabel uint32) *ofp.OfpOxmOfbField {
+	return &ofp.OfpOxmOfbField{Type: IPV6_FLABEL, Value: &ofp.OfpOxmOfbField_Ipv6Flabel{Ipv6Flabel: ipv6Flabel}}
+}
+
+func Icmpv6Type(icmpv6Type uint32) *ofp.OfpOxmOfbField {
+	return &ofp.OfpOxmOfbField{Type: ICMPV6_TYPE, Value: &ofp.OfpOxmOfbField_Icmpv6Type{Icmpv6Type: icmpv6Type}}
+}
+
+func Icmpv6Code(icmpv6Code uint32) *ofp.OfpOxmOfbField {
+	return &ofp.OfpOxmOfbField{Type: ICMPV6_CODE, Value: &ofp.OfpOxmOfbField_Icmpv6Code{Icmpv6Code: icmpv6Code}}
+}
+
+func Ipv6NdTarget(ipv6NdTarget []byte) *ofp.OfpOxmOfbField {
+	return &ofp.OfpOxmOfbField{Type: IPV6_ND_TARGET, Value: &ofp.OfpOxmOfbField_Ipv6NdTarget{Ipv6NdTarget: ipv6NdTarget}}
+}
+
+func OfbIpv6NdSll(ofbIpv6NdSll []byte) *ofp.OfpOxmOfbField {
+	return &ofp.OfpOxmOfbField{Type: OFB_IPV6_ND_SLL, Value: &ofp.OfpOxmOfbField_Ipv6NdSsl{Ipv6NdSsl: ofbIpv6NdSll}}
+}
+
+func Ipv6NdTll(ipv6NdTll []byte) *ofp.OfpOxmOfbField {
+	return &ofp.OfpOxmOfbField{Type: IPV6_ND_TLL, Value: &ofp.OfpOxmOfbField_Ipv6NdTll{Ipv6NdTll: ipv6NdTll}}
+}
+
+func MplsLabel(mplsLabel uint32) *ofp.OfpOxmOfbField {
+	return &ofp.OfpOxmOfbField{Type: MPLS_LABEL, Value: &ofp.OfpOxmOfbField_MplsLabel{MplsLabel: mplsLabel}}
+}
+
+func MplsTc(mplsTc uint32) *ofp.OfpOxmOfbField {
+	return &ofp.OfpOxmOfbField{Type: MPLS_TC, Value: &ofp.OfpOxmOfbField_MplsTc{MplsTc: mplsTc}}
+}
+
+func MplsBos(mplsBos uint32) *ofp.OfpOxmOfbField {
+	return &ofp.OfpOxmOfbField{Type: MPLS_BOS, Value: &ofp.OfpOxmOfbField_MplsBos{MplsBos: mplsBos}}
+}
+
+func PbbIsid(pbbIsid uint32) *ofp.OfpOxmOfbField {
+	return &ofp.OfpOxmOfbField{Type: PBB_ISID, Value: &ofp.OfpOxmOfbField_PbbIsid{PbbIsid: pbbIsid}}
+}
+
+func TunnelId(tunnelId uint64) *ofp.OfpOxmOfbField {
+	return &ofp.OfpOxmOfbField{Type: TUNNEL_ID, Value: &ofp.OfpOxmOfbField_TunnelId{TunnelId: tunnelId}}
+}
+
+func Ipv6Exthdr(ipv6Exthdr uint32) *ofp.OfpOxmOfbField {
+	return &ofp.OfpOxmOfbField{Type: IPV6_EXTHDR, Value: &ofp.OfpOxmOfbField_Ipv6Exthdr{Ipv6Exthdr: ipv6Exthdr}}
+}
+
+//frequently used extractors
+
+func excludeAction(action *ofp.OfpAction, exclude ...ofp.OfpActionType) bool {
+	for _, actionToExclude := range exclude {
+		if action.Type == actionToExclude {
+			return true
+		}
+	}
+	return false
+}
+
+func GetActions(flow *ofp.OfpFlowStats, exclude ...ofp.OfpActionType) []*ofp.OfpAction {
+	if flow == nil {
+		return nil
+	}
+	for _, instruction := range flow.Instructions {
+		if instruction.Type == uint32(ofp.OfpInstructionType_OFPIT_APPLY_ACTIONS) {
+			instActions := instruction.GetActions()
+			if instActions == nil {
+				return nil
+			}
+			if len(exclude) == 0 {
+				return instActions.Actions
+			} else {
+				filteredAction := make([]*ofp.OfpAction, 0)
+				for _, action := range instActions.Actions {
+					if !excludeAction(action, exclude...) {
+						filteredAction = append(filteredAction, action)
+					}
+				}
+				return filteredAction
+			}
+		}
+	}
+	return nil
+}
+
+func UpdateOutputPortByActionType(flow *ofp.OfpFlowStats, actionType uint32, toPort uint32) *ofp.OfpFlowStats {
+	if flow == nil {
+		return nil
+	}
+	nFlow := (proto.Clone(flow)).(*ofp.OfpFlowStats)
+	nFlow.Instructions = nil
+	nInsts := make([]*ofp.OfpInstruction, 0)
+	for _, instruction := range flow.Instructions {
+		if instruction.Type == actionType {
+			instActions := instruction.GetActions()
+			if instActions == nil {
+				return nil
+			}
+			nActions := make([]*ofp.OfpAction, 0)
+			for _, action := range instActions.Actions {
+				if action.GetOutput() != nil {
+					nActions = append(nActions, Output(toPort))
+				} else {
+					nActions = append(nActions, action)
+				}
+			}
+			instructionAction := ofp.OfpInstruction_Actions{Actions: &ofp.OfpInstructionActions{Actions: nActions}}
+			nInsts = append(nInsts, &ofp.OfpInstruction{Type: uint32(APPLY_ACTIONS), Data: &instructionAction})
+		} else {
+			nInsts = append(nInsts, instruction)
+		}
+	}
+	nFlow.Instructions = nInsts
+	return nFlow
+}
+
+func excludeOxmOfbField(field *ofp.OfpOxmOfbField, exclude ...ofp.OxmOfbFieldTypes) bool {
+	for _, fieldToExclude := range exclude {
+		if field.Type == fieldToExclude {
+			return true
+		}
+	}
+	return false
+}
+
+func GetOfbFields(flow *ofp.OfpFlowStats, exclude ...ofp.OxmOfbFieldTypes) []*ofp.OfpOxmOfbField {
+	if flow == nil || flow.Match == nil || flow.Match.Type != ofp.OfpMatchType_OFPMT_OXM {
+		return nil
+	}
+	ofbFields := make([]*ofp.OfpOxmOfbField, 0)
+	for _, field := range flow.Match.OxmFields {
+		if field.OxmClass == ofp.OfpOxmClass_OFPXMC_OPENFLOW_BASIC {
+			ofbFields = append(ofbFields, field.GetOfbField())
+		}
+	}
+	if len(exclude) == 0 {
+		return ofbFields
+	} else {
+		filteredFields := make([]*ofp.OfpOxmOfbField, 0)
+		for _, ofbField := range ofbFields {
+			if !excludeOxmOfbField(ofbField, exclude...) {
+				filteredFields = append(filteredFields, ofbField)
+			}
+		}
+		return filteredFields
+	}
+}
+
+func GetPacketOutPort(packet *ofp.OfpPacketOut) uint32 {
+	if packet == nil {
+		return 0
+	}
+	for _, action := range packet.GetActions() {
+		if action.Type == OUTPUT {
+			return action.GetOutput().Port
+		}
+	}
+	return 0
+}
+
+func GetOutPort(flow *ofp.OfpFlowStats) uint32 {
+	if flow == nil {
+		return 0
+	}
+	for _, action := range GetActions(flow) {
+		if action.Type == OUTPUT {
+			out := action.GetOutput()
+			if out == nil {
+				return 0
+			}
+			return out.GetPort()
+		}
+	}
+	return 0
+}
+
+func GetInPort(flow *ofp.OfpFlowStats) uint32 {
+	if flow == nil {
+		return 0
+	}
+	for _, field := range GetOfbFields(flow) {
+		if field.Type == IN_PORT {
+			return field.GetPort()
+		}
+	}
+	return 0
+}
+
+func GetGotoTableId(flow *ofp.OfpFlowStats) uint32 {
+	if flow == nil {
+		return 0
+	}
+	for _, instruction := range flow.Instructions {
+		if instruction.Type == uint32(ofp.OfpInstructionType_OFPIT_GOTO_TABLE) {
+			gotoTable := instruction.GetGotoTable()
+			if gotoTable == nil {
+				return 0
+			}
+			return gotoTable.GetTableId()
+		}
+	}
+	return 0
+}
+
+func GetMeterId(flow *ofp.OfpFlowStats) uint32 {
+	if flow == nil {
+		return 0
+	}
+	for _, instruction := range flow.Instructions {
+		if instruction.Type == uint32(ofp.OfpInstructionType_OFPIT_METER) {
+			MeterInstruction := instruction.GetMeter()
+			if MeterInstruction == nil {
+				return 0
+			}
+			return MeterInstruction.GetMeterId()
+		}
+	}
+	return 0
+}
+
+func GetVlanVid(flow *ofp.OfpFlowStats) *uint32 {
+	if flow == nil {
+		return nil
+	}
+	for _, field := range GetOfbFields(flow) {
+		if field.Type == VLAN_VID {
+			ret := field.GetVlanVid()
+			return &ret
+		}
+	}
+	// Dont return 0 if the field is missing as vlan id value 0 has meaning and cannot be overloaded as "not found"
+	return nil
+}
+
+func GetTunnelId(flow *ofp.OfpFlowStats) uint64 {
+	if flow == nil {
+		return 0
+	}
+	for _, field := range GetOfbFields(flow) {
+		if field.Type == TUNNEL_ID {
+			return field.GetTunnelId()
+		}
+	}
+	return 0
+}
+
+//GetMetaData - legacy get method (only want lower 32 bits)
+func GetMetaData(flow *ofp.OfpFlowStats) uint32 {
+	if flow == nil {
+		return 0
+	}
+	for _, field := range GetOfbFields(flow) {
+		if field.Type == METADATA {
+			return uint32(field.GetTableMetadata() & 0xFFFFFFFF)
+		}
+	}
+	log.Debug("No-metadata-present")
+	return 0
+}
+
+func GetMetaData64Bit(flow *ofp.OfpFlowStats) uint64 {
+	if flow == nil {
+		return 0
+	}
+	for _, field := range GetOfbFields(flow) {
+		if field.Type == METADATA {
+			return field.GetTableMetadata()
+		}
+	}
+	log.Debug("No-metadata-present")
+	return 0
+}
+
+// function returns write metadata value from write_metadata action field
+func GetMetadataFromWriteMetadataAction(flow *ofp.OfpFlowStats) uint64 {
+	if flow != nil {
+		for _, instruction := range flow.Instructions {
+			if instruction.Type == uint32(WRITE_METADATA) {
+				if writeMetadata := instruction.GetWriteMetadata(); writeMetadata != nil {
+					return writeMetadata.GetMetadata()
+				}
+			}
+		}
+	}
+	log.Debugw("No-write-metadata-present", log.Fields{"flow": flow})
+	return 0
+}
+
+func GetTechProfileIDFromWriteMetaData(metadata uint64) uint16 {
+	/*
+	   Write metadata instruction value (metadata) is 8 bytes:
+	   MS 2 bytes: C Tag
+	   Next 2 bytes: Technology Profile Id
+	   Next 4 bytes: Port number (uni or nni)
+
+	   This is set in the ONOS OltPipeline as a write metadata instruction
+	*/
+	var tpId uint16 = 0
+	log.Debugw("Write metadata value for Techprofile ID", log.Fields{"metadata": metadata})
+	if metadata != 0 {
+		tpId = uint16((metadata >> 32) & 0xFFFF)
+		log.Debugw("Found techprofile ID from write metadata action", log.Fields{"tpid": tpId})
+	}
+	return tpId
+}
+
+func GetEgressPortNumberFromWriteMetadata(flow *ofp.OfpFlowStats) uint32 {
+	/*
+			  Write metadata instruction value (metadata) is 8 bytes:
+		    	MS 2 bytes: C Tag
+		    	Next 2 bytes: Technology Profile Id
+		    	Next 4 bytes: Port number (uni or nni)
+		    	This is set in the ONOS OltPipeline as a write metadata instruction
+	*/
+	var uniPort uint32 = 0
+	md := GetMetadataFromWriteMetadataAction(flow)
+	log.Debugw("Metadata found for egress/uni port ", log.Fields{"metadata": md})
+	if md != 0 {
+		uniPort = uint32(md & 0xFFFFFFFF)
+		log.Debugw("Found EgressPort from write metadata action", log.Fields{"egress_port": uniPort})
+	}
+	return uniPort
+
+}
+
+func GetInnerTagFromMetaData(flow *ofp.OfpFlowStats) uint16 {
+	/*
+			  Write metadata instruction value (metadata) is 8 bytes:
+		    	MS 2 bytes: C Tag
+		    	Next 2 bytes: Technology Profile Id
+		    	Next 4 bytes: Port number (uni or nni)
+		    	This is set in the ONOS OltPipeline as a write metadata instruction
+	*/
+	var innerTag uint16 = 0
+	md := GetMetadataFromWriteMetadataAction(flow)
+	if md != 0 {
+		innerTag = uint16((md >> 48) & 0xFFFF)
+		log.Debugw("Found  CVLAN from write metadate action", log.Fields{"c_vlan": innerTag})
+	}
+	return innerTag
+}
+
+//GetInnerTagFromMetaData retrieves the inner tag from the Metadata_ofp. The port number (UNI on ONU) is in the
+// lower 32-bits of Metadata_ofp and the inner_tag is in the upper 32-bits. This is set in the ONOS OltPipeline as
+//// a Metadata_ofp field
+/*func GetInnerTagFromMetaData(flow *ofp.OfpFlowStats) uint64 {
+	md := GetMetaData64Bit(flow)
+	if md == 0 {
+		return 0
+	}
+	if md <= 0xffffffff {
+		log.Debugw("onos-upgrade-suggested", log.Fields{"Metadata_ofp": md, "message": "Legacy MetaData detected form OltPipeline"})
+		return md
+	}
+	return (md >> 32) & 0xffffffff
+}*/
+
+// Extract the child device port from a flow that contains the parent device peer port.  Typically the UNI port of an
+// ONU child device.  Per TST agreement this will be the lower 32 bits of tunnel id reserving upper 32 bits for later
+// use
+func GetChildPortFromTunnelId(flow *ofp.OfpFlowStats) uint32 {
+	tid := GetTunnelId(flow)
+	if tid == 0 {
+		return 0
+	}
+	// Per TST agreement we are keeping any child port id (uni port id) in the lower 32 bits
+	return uint32(tid & 0xffffffff)
+}
+
+func HasNextTable(flow *ofp.OfpFlowStats) bool {
+	if flow == nil {
+		return false
+	}
+	return GetGotoTableId(flow) != 0
+}
+
+func GetGroup(flow *ofp.OfpFlowStats) uint32 {
+	if flow == nil {
+		return 0
+	}
+	for _, action := range GetActions(flow) {
+		if action.Type == GROUP {
+			grp := action.GetGroup()
+			if grp == nil {
+				return 0
+			}
+			return grp.GetGroupId()
+		}
+	}
+	return 0
+}
+
+func HasGroup(flow *ofp.OfpFlowStats) bool {
+	return GetGroup(flow) != 0
+}
+
+// GetNextTableId returns the next table ID if the "table_id" is present in the map, otherwise return nil
+func GetNextTableId(kw OfpFlowModArgs) *uint32 {
+	if val, exist := kw["table_id"]; exist {
+		ret := uint32(val)
+		return &ret
+	}
+	return nil
+}
+
+// GetMeterIdFlowModArgs returns the meterId if the "meter_id" is present in the map, otherwise return 0
+func GetMeterIdFlowModArgs(kw OfpFlowModArgs) uint32 {
+	if val, exist := kw["meter_id"]; exist {
+		return uint32(val)
+	}
+	return 0
+}
+
+// Function returns the metadata if the "write_metadata" is present in the map, otherwise return nil
+func GetMetadataFlowModArgs(kw OfpFlowModArgs) uint64 {
+	if val, exist := kw["write_metadata"]; exist {
+		ret := uint64(val)
+		return ret
+	}
+	return 0
+}
+
+// Return unique 64-bit integer hash for flow covering the following attributes:
+// 'table_id', 'priority', 'flags', 'cookie', 'match', '_instruction_string'
+func HashFlowStats(flow *ofp.OfpFlowStats) uint64 {
+	if flow == nil { // Should never happen
+		return 0
+	}
+	// Create string with the instructions field first
+	var instructionString bytes.Buffer
+	for _, instruction := range flow.Instructions {
+		instructionString.WriteString(instruction.String())
+	}
+	var flowString = fmt.Sprintf("%d%d%d%d%s%s", flow.TableId, flow.Priority, flow.Flags, flow.Cookie, flow.Match.String(), instructionString.String())
+	h := md5.New()
+	h.Write([]byte(flowString))
+	hash := big.NewInt(0)
+	hash.SetBytes(h.Sum(nil))
+	return hash.Uint64()
+}
+
+// flowStatsEntryFromFlowModMessage maps an ofp_flow_mod message to an ofp_flow_stats message
+func FlowStatsEntryFromFlowModMessage(mod *ofp.OfpFlowMod) *ofp.OfpFlowStats {
+	flow := &ofp.OfpFlowStats{}
+	if mod == nil {
+		return flow
+	}
+	flow.TableId = mod.TableId
+	flow.Priority = mod.Priority
+	flow.IdleTimeout = mod.IdleTimeout
+	flow.HardTimeout = mod.HardTimeout
+	flow.Flags = mod.Flags
+	flow.Cookie = mod.Cookie
+	flow.Match = mod.Match
+	flow.Instructions = mod.Instructions
+	flow.Id = HashFlowStats(flow)
+	return flow
+}
+
+func GroupEntryFromGroupMod(mod *ofp.OfpGroupMod) *ofp.OfpGroupEntry {
+	group := &ofp.OfpGroupEntry{}
+	if mod == nil {
+		return group
+	}
+	group.Desc = &ofp.OfpGroupDesc{Type: mod.Type, GroupId: mod.GroupId, Buckets: mod.Buckets}
+	group.Stats = &ofp.OfpGroupStats{GroupId: mod.GroupId}
+	//TODO do we need to instantiate bucket bins?
+	return group
+}
+
+// flowStatsEntryFromFlowModMessage maps an ofp_flow_mod message to an ofp_flow_stats message
+func MeterEntryFromMeterMod(meterMod *ofp.OfpMeterMod) *ofp.OfpMeterEntry {
+	bandStats := make([]*ofp.OfpMeterBandStats, 0)
+	meter := &ofp.OfpMeterEntry{Config: &ofp.OfpMeterConfig{},
+		Stats: &ofp.OfpMeterStats{BandStats: bandStats}}
+	if meterMod == nil {
+		log.Error("Invalid meter mod command")
+		return meter
+	}
+	// config init
+	meter.Config.MeterId = meterMod.MeterId
+	meter.Config.Flags = meterMod.Flags
+	meter.Config.Bands = meterMod.Bands
+	// meter stats init
+	meter.Stats.MeterId = meterMod.MeterId
+	meter.Stats.FlowCount = 0
+	meter.Stats.PacketInCount = 0
+	meter.Stats.ByteInCount = 0
+	meter.Stats.DurationSec = 0
+	meter.Stats.DurationNsec = 0
+	// band stats init
+	for _, _ = range meterMod.Bands {
+		band := &ofp.OfpMeterBandStats{}
+		band.PacketBandCount = 0
+		band.ByteBandCount = 0
+		bandStats = append(bandStats, band)
+	}
+	meter.Stats.BandStats = bandStats
+	log.Debugw("Allocated meter entry", log.Fields{"meter": *meter})
+	return meter
+
+}
+
+func GetMeterIdFromFlow(flow *ofp.OfpFlowStats) uint32 {
+	if flow != nil {
+		for _, instruction := range flow.Instructions {
+			if instruction.Type == uint32(METER_ACTION) {
+				if meterInst := instruction.GetMeter(); meterInst != nil {
+					return meterInst.GetMeterId()
+				}
+			}
+		}
+	}
+
+	return uint32(0)
+}
+
+func MkOxmFields(matchFields []ofp.OfpOxmField) []*ofp.OfpOxmField {
+	oxmFields := make([]*ofp.OfpOxmField, 0)
+	for _, matchField := range matchFields {
+		oxmField := ofp.OfpOxmField{OxmClass: ofp.OfpOxmClass_OFPXMC_OPENFLOW_BASIC, Field: matchField.Field}
+		oxmFields = append(oxmFields, &oxmField)
+	}
+	return oxmFields
+}
+
+func MkInstructionsFromActions(actions []*ofp.OfpAction) []*ofp.OfpInstruction {
+	instructions := make([]*ofp.OfpInstruction, 0)
+	instructionAction := ofp.OfpInstruction_Actions{Actions: &ofp.OfpInstructionActions{Actions: actions}}
+	instruction := ofp.OfpInstruction{Type: uint32(APPLY_ACTIONS), Data: &instructionAction}
+	instructions = append(instructions, &instruction)
+	return instructions
+}
+
+// Convenience function to generare ofp_flow_mod message with OXM BASIC match composed from the match_fields, and
+// single APPLY_ACTIONS instruction with a list if ofp_action objects.
+func MkSimpleFlowMod(matchFields []*ofp.OfpOxmField, actions []*ofp.OfpAction, command *ofp.OfpFlowModCommand, kw OfpFlowModArgs) *ofp.OfpFlowMod {
+
+	// Process actions instructions
+	instructions := make([]*ofp.OfpInstruction, 0)
+	instructionAction := ofp.OfpInstruction_Actions{Actions: &ofp.OfpInstructionActions{Actions: actions}}
+	instruction := ofp.OfpInstruction{Type: uint32(APPLY_ACTIONS), Data: &instructionAction}
+	instructions = append(instructions, &instruction)
+
+	// Process next table
+	if tableId := GetNextTableId(kw); tableId != nil {
+		var instGotoTable ofp.OfpInstruction_GotoTable
+		instGotoTable.GotoTable = &ofp.OfpInstructionGotoTable{TableId: *tableId}
+		inst := ofp.OfpInstruction{Type: uint32(ofp.OfpInstructionType_OFPIT_GOTO_TABLE), Data: &instGotoTable}
+		instructions = append(instructions, &inst)
+	}
+	// Process meter action
+	if meterId := GetMeterIdFlowModArgs(kw); meterId != 0 {
+		var instMeter ofp.OfpInstruction_Meter
+		instMeter.Meter = &ofp.OfpInstructionMeter{MeterId: meterId}
+		inst := ofp.OfpInstruction{Type: uint32(METER_ACTION), Data: &instMeter}
+		instructions = append(instructions, &inst)
+	}
+	//process write_metadata action
+	if metadata := GetMetadataFlowModArgs(kw); metadata != 0 {
+		var instWriteMetadata ofp.OfpInstruction_WriteMetadata
+		instWriteMetadata.WriteMetadata = &ofp.OfpInstructionWriteMetadata{Metadata: metadata}
+		inst := ofp.OfpInstruction{Type: uint32(WRITE_METADATA), Data: &instWriteMetadata}
+		instructions = append(instructions, &inst)
+	}
+
+	// Process match fields
+	oxmFields := make([]*ofp.OfpOxmField, 0)
+	for _, matchField := range matchFields {
+		oxmField := ofp.OfpOxmField{OxmClass: ofp.OfpOxmClass_OFPXMC_OPENFLOW_BASIC, Field: matchField.Field}
+		oxmFields = append(oxmFields, &oxmField)
+	}
+	var match ofp.OfpMatch
+	match.Type = ofp.OfpMatchType_OFPMT_OXM
+	match.OxmFields = oxmFields
+
+	// Create ofp_flow_message
+	msg := &ofp.OfpFlowMod{}
+	if command == nil {
+		msg.Command = ofp.OfpFlowModCommand_OFPFC_ADD
+	} else {
+		msg.Command = *command
+	}
+	msg.Instructions = instructions
+	msg.Match = &match
+
+	// Set the variadic argument values
+	msg = setVariadicModAttributes(msg, kw)
+
+	return msg
+}
+
+func MkMulticastGroupMod(groupId uint32, buckets []*ofp.OfpBucket, command *ofp.OfpGroupModCommand) *ofp.OfpGroupMod {
+	group := &ofp.OfpGroupMod{}
+	if command == nil {
+		group.Command = ofp.OfpGroupModCommand_OFPGC_ADD
+	} else {
+		group.Command = *command
+	}
+	group.Type = ofp.OfpGroupType_OFPGT_ALL
+	group.GroupId = groupId
+	group.Buckets = buckets
+	return group
+}
+
+//SetVariadicModAttributes sets only uint64 or uint32 fields of the ofp_flow_mod message
+func setVariadicModAttributes(mod *ofp.OfpFlowMod, args OfpFlowModArgs) *ofp.OfpFlowMod {
+	if args == nil {
+		return mod
+	}
+	for key, val := range args {
+		switch key {
+		case "cookie":
+			mod.Cookie = val
+		case "cookie_mask":
+			mod.CookieMask = val
+		case "table_id":
+			mod.TableId = uint32(val)
+		case "idle_timeout":
+			mod.IdleTimeout = uint32(val)
+		case "hard_timeout":
+			mod.HardTimeout = uint32(val)
+		case "priority":
+			mod.Priority = uint32(val)
+		case "buffer_id":
+			mod.BufferId = uint32(val)
+		case "out_port":
+			mod.OutPort = uint32(val)
+		case "out_group":
+			mod.OutGroup = uint32(val)
+		case "flags":
+			mod.Flags = uint32(val)
+		}
+	}
+	return mod
+}
+
+func MkPacketIn(port uint32, packet []byte) *ofp.OfpPacketIn {
+	packetIn := &ofp.OfpPacketIn{
+		Reason: ofp.OfpPacketInReason_OFPR_ACTION,
+		Match: &ofp.OfpMatch{
+			Type: ofp.OfpMatchType_OFPMT_OXM,
+			OxmFields: []*ofp.OfpOxmField{
+				{
+					OxmClass: ofp.OfpOxmClass_OFPXMC_OPENFLOW_BASIC,
+					Field: &ofp.OfpOxmField_OfbField{
+						OfbField: InPort(port)},
+				},
+			},
+		},
+		Data: packet,
+	}
+	return packetIn
+}
+
+// MkFlowStat is a helper method to build flows
+func MkFlowStat(fa *FlowArgs) *ofp.OfpFlowStats {
+	//Build the match-fields
+	matchFields := make([]*ofp.OfpOxmField, 0)
+	for _, val := range fa.MatchFields {
+		matchFields = append(matchFields, &ofp.OfpOxmField{Field: &ofp.OfpOxmField_OfbField{OfbField: val}})
+	}
+	return FlowStatsEntryFromFlowModMessage(MkSimpleFlowMod(matchFields, fa.Actions, fa.Command, fa.KV))
+}
+
+func MkGroupStat(ga *GroupArgs) *ofp.OfpGroupEntry {
+	return GroupEntryFromGroupMod(MkMulticastGroupMod(ga.GroupId, ga.Buckets, ga.Command))
+}
+
+type OfpFlowModArgs map[string]uint64
+
+type FlowArgs struct {
+	MatchFields []*ofp.OfpOxmOfbField
+	Actions     []*ofp.OfpAction
+	Command     *ofp.OfpFlowModCommand
+	Priority    uint32
+	KV          OfpFlowModArgs
+}
+
+type GroupArgs struct {
+	GroupId uint32
+	Buckets []*ofp.OfpBucket
+	Command *ofp.OfpGroupModCommand
+}
+
+type FlowsAndGroups struct {
+	Flows  *ordered_map.OrderedMap
+	Groups *ordered_map.OrderedMap
+}
+
+func NewFlowsAndGroups() *FlowsAndGroups {
+	var fg FlowsAndGroups
+	fg.Flows = ordered_map.NewOrderedMap()
+	fg.Groups = ordered_map.NewOrderedMap()
+	return &fg
+}
+
+func (fg *FlowsAndGroups) Copy() *FlowsAndGroups {
+	copyFG := NewFlowsAndGroups()
+	iter := fg.Flows.IterFunc()
+	for kv, ok := iter(); ok; kv, ok = iter() {
+		if protoMsg, isMsg := kv.Value.(*ofp.OfpFlowStats); isMsg {
+			copyFG.Flows.Set(kv.Key, proto.Clone(protoMsg))
+		}
+	}
+	iter = fg.Groups.IterFunc()
+	for kv, ok := iter(); ok; kv, ok = iter() {
+		if protoMsg, isMsg := kv.Value.(*ofp.OfpGroupEntry); isMsg {
+			copyFG.Groups.Set(kv.Key, proto.Clone(protoMsg))
+		}
+	}
+	return copyFG
+}
+
+func (fg *FlowsAndGroups) GetFlow(index int) *ofp.OfpFlowStats {
+	iter := fg.Flows.IterFunc()
+	pos := 0
+	for kv, ok := iter(); ok; kv, ok = iter() {
+		if pos == index {
+			if protoMsg, isMsg := kv.Value.(*ofp.OfpFlowStats); isMsg {
+				return protoMsg
+			}
+			return nil
+		}
+		pos += 1
+	}
+	return nil
+}
+
+func (fg *FlowsAndGroups) ListFlows() []*ofp.OfpFlowStats {
+	flows := make([]*ofp.OfpFlowStats, 0)
+	iter := fg.Flows.IterFunc()
+	for kv, ok := iter(); ok; kv, ok = iter() {
+		if protoMsg, isMsg := kv.Value.(*ofp.OfpFlowStats); isMsg {
+			flows = append(flows, protoMsg)
+		}
+	}
+	return flows
+}
+
+func (fg *FlowsAndGroups) ListGroups() []*ofp.OfpGroupEntry {
+	groups := make([]*ofp.OfpGroupEntry, 0)
+	iter := fg.Groups.IterFunc()
+	for kv, ok := iter(); ok; kv, ok = iter() {
+		if protoMsg, isMsg := kv.Value.(*ofp.OfpGroupEntry); isMsg {
+			groups = append(groups, protoMsg)
+		}
+	}
+	return groups
+}
+
+func (fg *FlowsAndGroups) String() string {
+	var buffer bytes.Buffer
+	iter := fg.Flows.IterFunc()
+	for kv, ok := iter(); ok; kv, ok = iter() {
+		if protoMsg, isMsg := kv.Value.(*ofp.OfpFlowStats); isMsg {
+			buffer.WriteString("\nFlow:\n")
+			buffer.WriteString(proto.MarshalTextString(protoMsg))
+			buffer.WriteString("\n")
+		}
+	}
+	iter = fg.Groups.IterFunc()
+	for kv, ok := iter(); ok; kv, ok = iter() {
+		if protoMsg, isMsg := kv.Value.(*ofp.OfpGroupEntry); isMsg {
+			buffer.WriteString("\nGroup:\n")
+			buffer.WriteString(proto.MarshalTextString(protoMsg))
+			buffer.WriteString("\n")
+		}
+	}
+	return buffer.String()
+}
+
+func (fg *FlowsAndGroups) AddFlow(flow *ofp.OfpFlowStats) {
+	if flow == nil {
+		return
+	}
+
+	if fg.Flows == nil {
+		fg.Flows = ordered_map.NewOrderedMap()
+	}
+	if fg.Groups == nil {
+		fg.Groups = ordered_map.NewOrderedMap()
+	}
+	//Add flow only if absent
+	if _, exist := fg.Flows.Get(flow.Id); !exist {
+		fg.Flows.Set(flow.Id, flow)
+	}
+}
+
+func (fg *FlowsAndGroups) AddGroup(group *ofp.OfpGroupEntry) {
+	if group == nil {
+		return
+	}
+
+	if fg.Flows == nil {
+		fg.Flows = ordered_map.NewOrderedMap()
+	}
+	if fg.Groups == nil {
+		fg.Groups = ordered_map.NewOrderedMap()
+	}
+	//Add group only if absent
+	if _, exist := fg.Groups.Get(group.Desc.GroupId); !exist {
+		fg.Groups.Set(group.Desc.GroupId, group)
+	}
+}
+
+//AddFrom add flows and groups from the argument into this structure only if they do not already exist
+func (fg *FlowsAndGroups) AddFrom(from *FlowsAndGroups) {
+	iter := from.Flows.IterFunc()
+	for kv, ok := iter(); ok; kv, ok = iter() {
+		if protoMsg, isMsg := kv.Value.(*ofp.OfpFlowStats); isMsg {
+			if _, exist := fg.Flows.Get(protoMsg.Id); !exist {
+				fg.Flows.Set(protoMsg.Id, protoMsg)
+			}
+		}
+	}
+	iter = from.Groups.IterFunc()
+	for kv, ok := iter(); ok; kv, ok = iter() {
+		if protoMsg, isMsg := kv.Value.(*ofp.OfpGroupEntry); isMsg {
+			if _, exist := fg.Groups.Get(protoMsg.Stats.GroupId); !exist {
+				fg.Groups.Set(protoMsg.Stats.GroupId, protoMsg)
+			}
+		}
+	}
+}
+
+type DeviceRules struct {
+	Rules map[string]*FlowsAndGroups
+}
+
+func NewDeviceRules() *DeviceRules {
+	var dr DeviceRules
+	dr.Rules = make(map[string]*FlowsAndGroups)
+	return &dr
+}
+
+func (dr *DeviceRules) Copy() *DeviceRules {
+	copyDR := NewDeviceRules()
+	if dr != nil {
+		for key, val := range dr.Rules {
+			if val != nil {
+				copyDR.Rules[key] = val.Copy()
+			}
+		}
+	}
+	return copyDR
+}
+
+func (dr *DeviceRules) ClearFlows(deviceId string) {
+	if _, exist := dr.Rules[deviceId]; exist {
+		dr.Rules[deviceId].Flows = ordered_map.NewOrderedMap()
+	}
+}
+
+func (dr *DeviceRules) FilterRules(deviceIds map[string]string) *DeviceRules {
+	filteredDR := NewDeviceRules()
+	for key, val := range dr.Rules {
+		if _, exist := deviceIds[key]; exist {
+			filteredDR.Rules[key] = val.Copy()
+		}
+	}
+	return filteredDR
+}
+
+func (dr *DeviceRules) AddFlow(deviceId string, flow *ofp.OfpFlowStats) {
+	if _, exist := dr.Rules[deviceId]; !exist {
+		dr.Rules[deviceId] = NewFlowsAndGroups()
+	}
+	dr.Rules[deviceId].AddFlow(flow)
+}
+
+func (dr *DeviceRules) GetRules() map[string]*FlowsAndGroups {
+	return dr.Rules
+}
+
+func (dr *DeviceRules) String() string {
+	var buffer bytes.Buffer
+	for key, value := range dr.Rules {
+		buffer.WriteString("DeviceId:")
+		buffer.WriteString(key)
+		buffer.WriteString(value.String())
+		buffer.WriteString("\n\n")
+	}
+	return buffer.String()
+}
+
+func (dr *DeviceRules) AddFlowsAndGroup(deviceId string, fg *FlowsAndGroups) {
+	if _, ok := dr.Rules[deviceId]; !ok {
+		dr.Rules[deviceId] = NewFlowsAndGroups()
+	}
+	dr.Rules[deviceId] = fg
+}
+
+// CreateEntryIfNotExist creates a new deviceId in the Map if it does not exist and assigns an
+// empty FlowsAndGroups to it.  Otherwise, it does nothing.
+func (dr *DeviceRules) CreateEntryIfNotExist(deviceId string) {
+	if _, ok := dr.Rules[deviceId]; !ok {
+		dr.Rules[deviceId] = NewFlowsAndGroups()
+	}
+}
+
+/*
+ *  Common flow routines
+ */
+
+//FindOverlappingFlows return a list of overlapping flow(s) where mod is the flow request
+func FindOverlappingFlows(flows []*ofp.OfpFlowStats, mod *ofp.OfpFlowMod) []*ofp.OfpFlowStats {
+	return nil //TODO - complete implementation
+}
+
+// FindFlowById returns the index of the flow in the flows array if present. Otherwise, it returns -1
+func FindFlowById(flows []*ofp.OfpFlowStats, flow *ofp.OfpFlowStats) int {
+	for idx, f := range flows {
+		if flow.Id == f.Id {
+			return idx
+		}
+	}
+	return -1
+}
+
+// FindFlows returns the index in flows where flow if present.  Otherwise, it returns -1
+func FindFlows(flows []*ofp.OfpFlowStats, flow *ofp.OfpFlowStats) int {
+	for idx, f := range flows {
+		if FlowMatch(f, flow) {
+			return idx
+		}
+	}
+	return -1
+}
+
+//FlowMatch returns true if two flows matches on the following flow attributes:
+//TableId, Priority, Flags, Cookie, Match
+func FlowMatch(f1 *ofp.OfpFlowStats, f2 *ofp.OfpFlowStats) bool {
+	if f1 == nil || f2 == nil {
+		return false
+	}
+	keysMatter := []string{"TableId", "Priority", "Flags", "Cookie", "Match"}
+	for _, key := range keysMatter {
+		switch key {
+		case "TableId":
+			if f1.TableId != f2.TableId {
+				return false
+			}
+		case "Priority":
+			if f1.Priority != f2.Priority {
+				return false
+			}
+		case "Flags":
+			if f1.Flags != f2.Flags {
+				return false
+			}
+		case "Cookie":
+			if f1.Cookie != f2.Cookie {
+				return false
+			}
+		case "Match":
+			if strings.Compare(f1.Match.String(), f2.Match.String()) != 0 {
+				return false
+			}
+		}
+	}
+	return true
+}
+
+//FlowMatchesMod returns True if given flow is "covered" by the wildcard flow_mod, taking into consideration of
+//both exact matches as well as masks-based match fields if any. Otherwise return False
+func FlowMatchesMod(flow *ofp.OfpFlowStats, mod *ofp.OfpFlowMod) bool {
+	if flow == nil || mod == nil {
+		return false
+	}
+	//Check if flow.cookie is covered by mod.cookie and mod.cookie_mask
+	if (flow.Cookie & mod.CookieMask) != (mod.Cookie & mod.CookieMask) {
+		return false
+	}
+
+	//Check if flow.table_id is covered by flow_mod.table_id
+	if mod.TableId != uint32(ofp.OfpTable_OFPTT_ALL) && flow.TableId != mod.TableId {
+		return false
+	}
+
+	//Check out_port
+	if (mod.OutPort&0x7fffffff) != uint32(ofp.OfpPortNo_OFPP_ANY) && !FlowHasOutPort(flow, mod.OutPort) {
+		return false
+	}
+
+	//	Check out_group
+	if (mod.OutGroup&0x7fffffff) != uint32(ofp.OfpGroup_OFPG_ANY) && !FlowHasOutGroup(flow, mod.OutGroup) {
+		return false
+	}
+
+	//Priority is ignored
+
+	//Check match condition
+	//If the flow_mod match field is empty, that is a special case and indicates the flow entry matches
+	if (mod.Match == nil) || (mod.Match.OxmFields == nil) || (len(mod.Match.OxmFields) == 0) {
+		//If we got this far and the match is empty in the flow spec, than the flow matches
+		return true
+	} // TODO : implement the flow match analysis
+	return false
+
+}
+
+//FlowHasOutPort returns True if flow has a output command with the given out_port
+func FlowHasOutPort(flow *ofp.OfpFlowStats, outPort uint32) bool {
+	if flow == nil {
+		return false
+	}
+	for _, instruction := range flow.Instructions {
+		if instruction.Type == uint32(ofp.OfpInstructionType_OFPIT_APPLY_ACTIONS) {
+			if instruction.GetActions() == nil {
+				return false
+			}
+			for _, action := range instruction.GetActions().Actions {
+				if action.Type == ofp.OfpActionType_OFPAT_OUTPUT {
+					if (action.GetOutput() != nil) && (action.GetOutput().Port == outPort) {
+						return true
+					}
+				}
+
+			}
+		}
+	}
+	return false
+}
+
+//FlowHasOutGroup return True if flow has a output command with the given out_group
+func FlowHasOutGroup(flow *ofp.OfpFlowStats, groupID uint32) bool {
+	if flow == nil {
+		return false
+	}
+	for _, instruction := range flow.Instructions {
+		if instruction.Type == uint32(ofp.OfpInstructionType_OFPIT_APPLY_ACTIONS) {
+			if instruction.GetActions() == nil {
+				return false
+			}
+			for _, action := range instruction.GetActions().Actions {
+				if action.Type == ofp.OfpActionType_OFPAT_GROUP {
+					if (action.GetGroup() != nil) && (action.GetGroup().GroupId == groupID) {
+						return true
+					}
+				}
+
+			}
+		}
+	}
+	return false
+}
+
+//FindGroup returns index of group if found, else returns -1
+func FindGroup(groups []*ofp.OfpGroupEntry, groupId uint32) int {
+	for idx, group := range groups {
+		if group.Desc.GroupId == groupId {
+			return idx
+		}
+	}
+	return -1
+}
+
+func FlowsDeleteByGroupId(flows []*ofp.OfpFlowStats, groupId uint32) (bool, []*ofp.OfpFlowStats) {
+	toKeep := make([]*ofp.OfpFlowStats, 0)
+
+	for _, f := range flows {
+		if !FlowHasOutGroup(f, groupId) {
+			toKeep = append(toKeep, f)
+		}
+	}
+	return len(toKeep) < len(flows), toKeep
+}
+
+func ToOfpOxmField(from []*ofp.OfpOxmOfbField) []*ofp.OfpOxmField {
+	matchFields := make([]*ofp.OfpOxmField, 0)
+	for _, val := range from {
+		matchFields = append(matchFields, &ofp.OfpOxmField{Field: &ofp.OfpOxmField_OfbField{OfbField: val}})
+	}
+	return matchFields
+}