Implement ListSessions of BGP API

flaps + routes imported in the stats are still missing.

protocols/bgp/metrics/bgp_peer_metrics.go

@@ -1,9 +1,11 @@
 package metrics
 
 import (
+	"fmt"
 	"time"
 
 	bnet "github.com/bio-routing/bio-rd/net"
+	"github.com/bio-routing/bio-rd/protocols/bgp/api"
 )
 
 const (
@@ -48,3 +50,25 @@ type BGPPeerMetrics struct {
 	// AddressFamilies provides metrics on AFI/SAFI level
 	AddressFamilies []*BGPAddressFamilyMetrics
 }
+
+// GetStateAsProto returns the state of this peer to be used by the BGP API
+func (m *BGPPeerMetrics) GetStateAsProto() api.Session_State {
+	switch m.State {
+	case StateDown:
+		return api.Session_Active // substitution
+	case StateIdle:
+		return api.Session_Idle
+	case StateConnect:
+		return api.Session_Connect
+	case StateActive:
+		return api.Session_Active
+	case StateOpenSent:
+		return api.Session_OpenSent
+	case StateOpenConfirm:
+		return api.Session_OpenConfirmed
+	case StateEstablished:
+		return api.Session_Established
+	default:
+		panic(fmt.Sprintf("Unknown state: %v", m.State))
+	}
+}

protocols/bgp/server/bgp_api.go

@@ -5,7 +5,9 @@ import (
 	"fmt"
 
 	"github.com/bio-routing/bio-rd/protocols/bgp/api"
+	"github.com/bio-routing/bio-rd/protocols/bgp/metrics"
 	"github.com/bio-routing/bio-rd/route"
+	"github.com/pkg/errors"
 
 	bnet "github.com/bio-routing/bio-rd/net"
 	routeapi "github.com/bio-routing/bio-rd/route/api"
@@ -22,8 +24,76 @@ func NewBGPAPIServer(s BGPServer) *BGPAPIServer {
 	}
 }
 
+// ListSessions lists all sessions the BGP server currently has
 func (s *BGPAPIServer) ListSessions(ctx context.Context, in *api.ListSessionsRequest) (*api.ListSessionsResponse, error) {
-	return nil, fmt.Errorf("Not implemented yet")
+	bgpMetrics, err := s.srv.Metrics()
+	if err != nil {
+		return nil, errors.Wrap(err, "Could not get peer metrics")
+	}
+
+	sessions := make([]*api.Session, 0)
+	for _, peerIP := range s.srv.GetPeers() {
+		peer := s.srv.GetPeerConfig(peerIP)
+		// find metrics for peer
+		var peerMetrics *metrics.BGPPeerMetrics
+		for _, peerMetricsEntry := range bgpMetrics.Peers {
+			if *peerMetricsEntry.IP == *peer.PeerAddress {
+				peerMetrics = peerMetricsEntry
+				break
+			}
+		}
+		if peerMetrics == nil {
+			return nil, fmt.Errorf("Could not find metrics for neighbor %s", peer.PeerAddress)
+		}
+
+		if in.Filter != nil {
+			if in.Filter.NeighborIp != nil {
+				filterNeighbor := bnet.IPFromProtoIP(in.Filter.NeighborIp)
+				if *filterNeighbor != *peerIP {
+					continue
+				}
+			}
+			if in.Filter.VrfName != "" {
+				if in.Filter.VrfName != peerMetrics.VRF {
+					continue
+				}
+			}
+		}
+
+		estSince := peerMetrics.Since.Unix()
+		if estSince < 0 {
+			// time not set, peer probably not up
+			estSince = 0
+		}
+		var routesReceived, routesSent uint64
+		for _, afiPeerMetrics := range peerMetrics.AddressFamilies {
+			routesReceived += afiPeerMetrics.RoutesReceived
+			routesSent += afiPeerMetrics.RoutesSent
+		}
+
+		session := &api.Session{
+			LocalAddress:    peer.LocalAddress.ToProto(),
+			NeighborAddress: peer.PeerAddress.ToProto(),
+			LocalAsn:        peer.LocalAS,
+			PeerAsn:         peer.PeerAS,
+			Status:          peerMetrics.GetStateAsProto(),
+			Stats: &api.SessionStats{
+				MessagesIn:     peerMetrics.UpdatesReceived,
+				MessagesOut:    peerMetrics.UpdatesSent,
+				RoutesReceived: routesReceived,
+				RoutesExported: routesSent,
+			},
+			EstablishedSince: uint64(estSince),
+			Description:      peer.Description,
+			VrfName:          peerMetrics.VRF,
+		}
+		sessions = append(sessions, session)
+	}
+
+	resp := &api.ListSessionsResponse{
+		Sessions: sessions,
+	}
+	return resp, nil
 }
 
 // DumpRIBIn dumps the RIB in of a peer for a given AFI/SAFI