BGP and VRF metrics (#204)

* first steps to metrics

* next small step

* fixed tests

* added comments

* postponed RouterAccepted and RoutesRejected to next step

* read update counters

* added test

* added missing test file

* Route not used any more

* added metrics for session state and time since establish

* increased test coverage, time since establish impl.

* added prom collector

* added metrics endpoint to BGP example

* added metrics for VRF

* removed commented metrics

* fixed logging inconsistency in example

* Update main.go

* gofmt

* fixed typo

routingtable/vrf/vrf.go

@@ -85,6 +85,7 @@ func (v *VRF) IPv6UnicastRIB() *locRIB.LocRIB {
 	return v.ribForAddressFamily(addressFamily{afi: afiIPv6, safi: safiUnicast})
 }
 
+// Name is the name of the VRF
 func (v *VRF) Name() string {
 	return v.name
 }
@@ -108,3 +109,13 @@ func (v *VRF) RIBByName(name string) (rib *locRIB.LocRIB, found bool) {
 	rib, found = v.ribNames[name]
 	return rib, found
 }
+
+func (v *VRF) nameForRIB(rib *locRIB.LocRIB) string {
+	for name, r := range v.ribNames {
+		if r == rib {
+			return name
+		}
+	}
+
+	return ""
+}

routingtable/vrf/vrf_registry.go

@@ -41,3 +41,17 @@ func (r *vrfRegistry) unregisterVRF(v *VRF) {
 
 	delete(r.vrfs, v.name)
 }
+
+func (r *vrfRegistry) list() []*VRF {
+	r.mu.Lock()
+	defer r.mu.Unlock()
+
+	l := make([]*VRF, len(r.vrfs))
+	i := 0
+	for _, v := range r.vrfs {
+		l[i] = v
+		i++
+	}
+
+	return l
+}