[nxos] Include LLDP adjacencies in Interface GetStatus

Retrieve LLDP neighbor information while fetching interface status. As
of now, this is only performed on physical interfaces with the use case
of cabling validation in mind. The GetStatus response now includes a
slice of adjacencies with a subset of the Cisco model for NXOS [1].

[1]
https://pubhub.devnetcloud.com/media/dme-docs-10-4-3/docs/Discovery%20Protocols/lldp%3AAdjEp/

Author: nikatza

internal/provider/cisco/nxos/lldp.go

@@ -41,3 +41,27 @@ func (*LLDPOper) IsListItem() {}
 func (*LLDPOper) XPath() string {
 	return "System/fm-items/lldp-items"
 }
+
+// LLDPAdjacencyItems represents the LLDP neighbor information for a single interface.
+type LLDPAdjacencyItems struct {
+	// ID is the identifier of the interface for which the LLDP neighbor information is being retrieved, e.g., "eth1/1".
+	ID       string `json:"-"`
+	AdjItems struct {
+		AdjEpList []struct {
+			ChassisIdT uint8  `json:"chassisIdT"`
+			ChassisIdV string `json:"chassisIdV"`
+			PortIdT    uint8  `json:"portIdT"`
+			PortIdV    string `json:"portIdV"`
+			PortDesc   string `json:"portDesc,omitempty"`
+			SysName    string `json:"sysName,omitempty"`
+			SysDesc    string `json:"sysDesc,omitempty"`
+			TTL        int32  `json:"ttl"`
+		} `json:"AdjEp-list,omitzero"`
+	} `json:"adj-items,omitzero"`
+}
+
+func (p *LLDPAdjacencyItems) XPath() string {
+	return "System/lldp-items/inst-items/if-items/If-list[id=" + p.ID + "]"
+}
+
+func (*LLDPAdjacencyItems) IsListItem() {}

internal/provider/cisco/nxos/lldp_test.go

@@ -3,6 +3,10 @@
 
 package nxos
 
+import (
+	"testing"
+)
+
 func init() {
 	lldp := &LLDP{
 		HoldTime:  NewOption(uint16(200)),
@@ -22,3 +26,32 @@ func init() {
 
 	Register("lldp", lldp)
 }
+
+func TestLLDPAdjacencyItems_XPath(t *testing.T) {
+	tests := []struct {
+		name string
+		id   string
+		want string
+	}{
+		{
+			name: "ethernet interface 1/1",
+			id:   "eth1/1",
+			want: "System/lldp-items/inst-items/if-items/If-list[id=eth1/1]",
+		},
+		{
+			name: "ethernet interface 1/48",
+			id:   "eth1/48",
+			want: "System/lldp-items/inst-items/if-items/If-list[id=eth1/48]",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			adj := &LLDPAdjacencyItems{ID: tt.id}
+			got := adj.XPath()
+			if got != tt.want {
+				t.Errorf("LLDPAdjacencyItems.XPath() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}

internal/provider/cisco/nxos/provider.go

@@ -1138,18 +1138,35 @@ func (p *Provider) GetInterfaceStatus(ctx context.Context, req *provider.Interfa
 	}
 
 	var (
-		operSt  OperSt
-		operMsg string
+		operSt          OperSt
+		operMsg         string
+		lldpAdjacencies []provider.LLDPAdjacency
 	)
 	switch req.Interface.Spec.Type {
 	case v1alpha1.InterfaceTypePhysical:
 		phys := new(PhysIfOperItems)
 		phys.ID = name
-		if err := p.client.GetState(ctx, phys); err != nil && !errors.Is(err, gnmiext.ErrNil) {
+		lldpAdj := new(LLDPAdjacencyItems)
+		lldpAdj.ID = name
+		if err := p.client.GetState(ctx, phys, lldpAdj); err != nil && !errors.Is(err, gnmiext.ErrNil) {
 			return provider.InterfaceStatus{}, err
 		}
 		operSt = phys.OperSt
 
+		for _, adj := range lldpAdj.AdjItems.AdjEpList {
+			neighbor := provider.LLDPAdjacency{
+				ChassisID:       adj.ChassisIdV,
+				ChassisIDType:   adj.ChassisIdT,
+				PortID:          adj.PortIdV,
+				PortIDType:      adj.PortIdT,
+				PortDescription: adj.PortDesc,
+				SysName:         adj.SysName,
+				SysDescription:  adj.SysDesc,
+				TTL:             uint32(adj.TTL), // #nosec G115
+			}
+			lldpAdjacencies = append(lldpAdjacencies, neighbor)
+		}
+
 	case v1alpha1.InterfaceTypeLoopback:
 		lb := new(LoopbackOperItems)
 		lb.ID = name
@@ -1179,10 +1196,13 @@ func (p *Provider) GetInterfaceStatus(ctx context.Context, req *provider.Interfa
 		return provider.InterfaceStatus{}, fmt.Errorf("unsupported interface type: %s", req.Interface.Spec.Type)
 	}
 
-	return provider.InterfaceStatus{
-		OperStatus:  operSt == OperStUp,
-		OperMessage: operMsg,
-	}, nil
+	status := provider.InterfaceStatus{
+		OperStatus:      operSt == OperStUp,
+		OperMessage:     operMsg,
+		LLDPAdjacencies: lldpAdjacencies,
+	}
+
+	return status, nil
 }
 
 var ErrInterfaceNotFound = errors.New("one or more interfaces do not exist")