Gateway Route imported/exported/preferred metrics

Collect metrics of routes imported, exported and preferred for each
gateways. The metrics are extracted and parsed from show protocol all
command in bird.

cmd/frontend/internal/env/config.go

@@ -44,4 +44,6 @@ type Config struct {
 	DelayConnectivity     time.Duration `default:"1s" desc:"Delay between checks with connectivity"`
 	DelayNoConnectivity   time.Duration `default:"3s" desc:"Delay between checks without connectivity"`
 	MaxSessionErrors      int           `default:"5" desc:"Max session errors when checking Bird until denounce"`
+	MetricsEnabled        bool          `default:"false" desc:"Enable the metrics collection" split_words:"true"`
+	MetricsPort           int           `default:"2224" desc:"Specify the port used to expose the metrics" split_words:"true"`
 }

cmd/frontend/internal/frontend/metrics.go

@@ -0,0 +1,260 @@
+/*
+Copyright (c) 2023 Nordix 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 frontend
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"regexp"
+	"strconv"
+	"strings"
+	"sync"
+
+	nspAPI "github.com/nordix/meridio/api/nsp/v1"
+	"github.com/nordix/meridio/cmd/frontend/internal/bird"
+	meridioMetrics "github.com/nordix/meridio/pkg/metrics"
+	"go.opentelemetry.io/otel"
+	"go.opentelemetry.io/otel/attribute"
+	"go.opentelemetry.io/otel/metric"
+)
+
+type GatewayMetrics struct {
+	meter            metric.Meter
+	gateways         map[string]*nspAPI.Gateway
+	metricAttributes []metric.ObserveOption
+	RoutingService   *bird.RoutingService
+	mu               sync.Mutex
+}
+
+func NewGatewayMetrics(metricAttributes []metric.ObserveOption) *GatewayMetrics {
+	meter := otel.GetMeterProvider().Meter(meridioMetrics.METER_NAME)
+	gm := &GatewayMetrics{
+		meter:            meter,
+		metricAttributes: metricAttributes,
+	}
+
+	return gm
+}
+
+func (gm *GatewayMetrics) Set(gateways []*nspAPI.Gateway) {
+	gatewaysMap := map[string]*nspAPI.Gateway{}
+
+	for _, gateway := range gateways {
+		gatewaysMap[fmt.Sprintf("NBR-%s", gateway.Name)] = gateway
+	}
+
+	gm.mu.Lock()
+	defer gm.mu.Unlock()
+	gm.gateways = gatewaysMap
+}
+
+// Collect collects the metrics for the gateways.
+func (gm *GatewayMetrics) Collect() error {
+	if gm.RoutingService == nil {
+		return errors.New("routing service not set for gateway metrics")
+	}
+
+	lp, err := gm.RoutingService.LookupCli()
+	if err != nil {
+		return err
+	}
+
+	_, err = gm.meter.Int64ObservableCounter(
+		meridioMetrics.MERIDIO_ATTRACTOR_GATEWAY_ROUTES_IMPORTED,
+		metric.WithUnit("routes"),
+		metric.WithDescription("Counts number of routes imported for a gateway."),
+		metric.WithInt64Callback(func(ctx context.Context, observer metric.Int64Observer) error {
+			return gm.observe(
+				ctx,
+				observer,
+				func(birdStats *BirdStats) int64 {
+					return int64(birdStats.routesImported)
+				},
+				lp,
+			)
+		}),
+	)
+	if err != nil {
+		return err
+	}
+
+	_, err = gm.meter.Int64ObservableCounter(
+		meridioMetrics.MERIDIO_ATTRACTOR_GATEWAY_ROUTES_EXPORTED,
+		metric.WithUnit("routes"),
+		metric.WithDescription("Counts number of routes exported for a gateway."),
+		metric.WithInt64Callback(func(ctx context.Context, observer metric.Int64Observer) error {
+			return gm.observe(
+				ctx,
+				observer,
+				func(birdStats *BirdStats) int64 {
+					return int64(birdStats.routesExported)
+				},
+				lp,
+			)
+		}),
+	)
+	if err != nil {
+		return err
+	}
+
+	_, err = gm.meter.Int64ObservableCounter(
+		meridioMetrics.MERIDIO_ATTRACTOR_GATEWAY_ROUTES_PREFERRED,
+		metric.WithUnit("routes"),
+		metric.WithDescription("Counts number of routes preferred for a gateway."),
+		metric.WithInt64Callback(func(ctx context.Context, observer metric.Int64Observer) error {
+			return gm.observe(
+				ctx,
+				observer,
+				func(birdStats *BirdStats) int64 {
+					return int64(birdStats.routesPreferred)
+				},
+				lp,
+			)
+		}),
+	)
+	if err != nil {
+		return err
+	}
+	return nil
+}
+
+func (gm *GatewayMetrics) observe(ctx context.Context, observer metric.Int64Observer, valueFunc func(*BirdStats) int64, lp string) error {
+	gm.mu.Lock()
+	defer gm.mu.Unlock()
+
+	spaOutput, err := gm.RoutingService.ShowProtocolSessions(ctx, lp, "")
+	if err != nil {
+		return err
+	}
+
+	birdStats := ParseShowProtocolsAll(spaOutput)
+
+	for _, birdStat := range birdStats {
+		gateway, exists := gm.gateways[birdStat.gatewayName]
+		if !exists {
+			continue
+		}
+
+		metricAttributes := []metric.ObserveOption{
+			metric.WithAttributes(attribute.String("Protocol", getProtocolName(gateway))),
+			metric.WithAttributes(attribute.String("Gateway", gateway.Name)),
+			metric.WithAttributes(attribute.String("IP", gateway.Address)),
+		}
+		metricAttributes = append(metricAttributes, gm.metricAttributes...)
+
+		observer.Observe(
+			valueFunc(birdStat),
+			metricAttributes...,
+		)
+	}
+
+	return nil
+}
+
+func getProtocolName(gateway *nspAPI.Gateway) string {
+	res := "unknown"
+	switch strings.ToLower(gateway.Protocol) {
+	case "bgp":
+		res = "BGP"
+	case "static":
+		res = "Static"
+	}
+	if gateway.Bfd {
+		res = fmt.Sprintf("%s+BFD", res)
+	}
+	return res
+}
+
+type BirdStats struct {
+	gatewayName     string
+	routesImported  int
+	routesExported  int
+	routesPreferred int
+}
+
+func (bs *BirdStats) String() string {
+	return fmt.Sprintf("%s (%d, %d, %d)", bs.gatewayName, bs.routesImported, bs.routesExported, bs.routesPreferred)
+}
+
+func ParseShowProtocolsAll(output string) []*BirdStats {
+	res := []*BirdStats{}
+
+	protocols := strings.Split(output, "\n\n")
+
+	regex := regexp.MustCompile(`(?m)    Routes:.*`)
+
+	for _, protocol := range protocols {
+		protocolName := strings.Split(protocol, " ")
+
+		if len(protocolName) <= 0 {
+			continue
+		}
+
+		newStat := &BirdStats{
+			gatewayName:     protocolName[0],
+			routesImported:  0,
+			routesExported:  0,
+			routesPreferred: 0,
+		}
+
+		routes := regex.FindAllString(protocol, -1)
+
+		if len(routes) <= 0 {
+			res = append(res, newStat)
+			continue
+		}
+
+		routesStats := strings.ReplaceAll(routes[0], "Routes:", "")
+		routesStats = strings.ReplaceAll(routesStats, "imported", "")
+		routesStats = strings.ReplaceAll(routesStats, "exported", "")
+		routesStats = strings.ReplaceAll(routesStats, "preferred", "")
+		routesStats = strings.ReplaceAll(routesStats, " ", "")
+		routesStatsSlice := strings.Split(routesStats, ",")
+
+		if len(routesStatsSlice) != 3 {
+			res = append(res, newStat)
+			continue
+		}
+
+		routesImported, err := strconv.Atoi(routesStatsSlice[0])
+		if err != nil {
+			res = append(res, newStat)
+			continue
+		}
+
+		routesExported, err := strconv.Atoi(routesStatsSlice[1])
+		if err != nil {
+			res = append(res, newStat)
+			continue
+		}
+
+		routesPreferred, err := strconv.Atoi(routesStatsSlice[2])
+		if err != nil {
+			res = append(res, newStat)
+			continue
+		}
+
+		newStat.routesImported = routesImported
+		newStat.routesExported = routesExported
+		newStat.routesPreferred = routesPreferred
+
+		res = append(res, newStat)
+	}
+
+	return res
+}