From 80fea91e3801b95a112cf9e2411c521732eda94d Mon Sep 17 00:00:00 2001
From: Botond Szirtes <botond.szirtes@est.tech>
Date: Mon, 29 Jul 2024 14:19:32 +0200
Subject: [PATCH] Add an option to expose Prometheus metrics via http/s server

Signed-off-by: Botond Szirtes <botond.szirtes@est.tech>
---
 pkg/networkservice/metrics/stats/common.go    | 18 ++++
 .../metrics/stats/prometheus.go               | 87 +++++++++++++++++++
 2 files changed, 105 insertions(+)
 create mode 100644 pkg/networkservice/metrics/stats/prometheus.go

diff --git a/pkg/networkservice/metrics/stats/common.go b/pkg/networkservice/metrics/stats/common.go
index 60d613d1..bf1d5600 100644
--- a/pkg/networkservice/metrics/stats/common.go
+++ b/pkg/networkservice/metrics/stats/common.go
@@ -32,6 +32,7 @@ import (
 
 	"github.com/networkservicemesh/api/pkg/api/networkservice"
 	"github.com/networkservicemesh/sdk/pkg/tools/log"
+	"github.com/networkservicemesh/sdk/pkg/tools/opentelemetry"
 	"github.com/pkg/errors"
 
 	"github.com/networkservicemesh/sdk-vpp/pkg/tools/ifindex"
@@ -67,6 +68,23 @@ func retrieveMetrics(ctx context.Context, statsConn *core.StatsConnection, segme
 		segment.Metrics[addName+"rx_packets"] = strconv.FormatUint(iface.Rx.Packets, 10)
 		segment.Metrics[addName+"tx_packets"] = strconv.FormatUint(iface.Tx.Packets, 10)
 		segment.Metrics[addName+"drops"] = strconv.FormatUint(iface.Drops, 10)
+
+		if opentelemetry.IsPrometheusEnabled() {
+			if addName == "server_" {
+				ServerRxBytes.Set(float64(iface.Rx.Bytes))
+				ServerTxBytes.Set(float64(iface.Tx.Bytes))
+				ServerRxPackets.Set(float64(iface.Rx.Packets))
+				ServerTxPackets.Set(float64(iface.Tx.Packets))
+				ServerDrops.Set(float64(iface.Drops))
+			} else {
+				ClientRxBytes.Set(float64(iface.Rx.Bytes))
+				ClientTxBytes.Set(float64(iface.Tx.Bytes))
+				ClientRxPackets.Set(float64(iface.Rx.Packets))
+				ClientTxPackets.Set(float64(iface.Tx.Packets))
+				ClientDrops.Set(float64(iface.Drops))
+			}
+		}
+
 		break
 	}
 }
diff --git a/pkg/networkservice/metrics/stats/prometheus.go b/pkg/networkservice/metrics/stats/prometheus.go
new file mode 100644
index 00000000..dec2cb0d
--- /dev/null
+++ b/pkg/networkservice/metrics/stats/prometheus.go
@@ -0,0 +1,87 @@
+package stats
+
+import (
+	"github.com/networkservicemesh/sdk/pkg/tools/opentelemetry"
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+var (
+	ClientRxBytes = prometheus.NewGauge(
+		prometheus.GaugeOpts{
+			Name: "client_rx_bytes_total",
+			Help: "Total received bytes by client",
+		},
+	)
+	ClientTxBytes = prometheus.NewGauge(
+		prometheus.GaugeOpts{
+			Name: "client_tx_bytes_total",
+			Help: "Total transmitted bytes by client",
+		},
+	)
+	ClientRxPackets = prometheus.NewGauge(
+		prometheus.GaugeOpts{
+			Name: "client_rx_packets_total",
+			Help: "Total received packets by client",
+		},
+	)
+	ClientTxPackets = prometheus.NewGauge(
+		prometheus.GaugeOpts{
+			Name: "client_tx_packets_total",
+			Help: "Total transmitted packets by client",
+		},
+	)
+	ClientDrops = prometheus.NewGauge(
+		prometheus.GaugeOpts{
+			Name: "client_drops_total",
+			Help: "Total drops by client",
+		},
+	)
+	ServerRxBytes = prometheus.NewGauge(
+		prometheus.GaugeOpts{
+			Name: "server_rx_bytes_total",
+			Help: "Total received bytes by server",
+		},
+	)
+	ServerTxBytes = prometheus.NewGauge(
+		prometheus.GaugeOpts{
+			Name: "server_tx_bytes_total",
+			Help: "Total transmitted bytes by server",
+		},
+	)
+
+	ServerRxPackets = prometheus.NewGauge(
+		prometheus.GaugeOpts{
+			Name: "server_rx_packets_total",
+			Help: "Total received packets by server",
+		},
+	)
+
+	ServerTxPackets = prometheus.NewGauge(
+		prometheus.GaugeOpts{
+			Name: "server_tx_packets_total",
+			Help: "Total transmitted packets by server",
+		},
+	)
+
+	ServerDrops = prometheus.NewGauge(
+		prometheus.GaugeOpts{
+			Name: "server_drops_total",
+			Help: "Total drops by server",
+		},
+	)
+)
+
+func init() {
+	if opentelemetry.IsPrometheusEnabled() {
+		prometheus.MustRegister(ClientRxBytes)
+		prometheus.MustRegister(ClientTxBytes)
+		prometheus.MustRegister(ClientRxPackets)
+		prometheus.MustRegister(ClientTxPackets)
+		prometheus.MustRegister(ClientDrops)
+		prometheus.MustRegister(ServerRxBytes)
+		prometheus.MustRegister(ServerTxBytes)
+		prometheus.MustRegister(ServerRxPackets)
+		prometheus.MustRegister(ServerTxPackets)
+		prometheus.MustRegister(ServerDrops)
+	}
+}