AIX: Add netinterface collector

While having overlap with NetAdpter metrics, the metrics are slightly different
so need to be exposed as well.

Signed-off-by: Johannes Ziemke <github@5pi.de>
Signed-off-by: Shashwat Hiregoudar <shashwat.h@flipkart.com>

collector/netinterface_aix.go

@@ -0,0 +1,86 @@
+// Copyright 2025 The Prometheus Authors
+// 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.
+
+//go:build !nonetinterface
+// +build !nonetinterface
+
+package collector
+
+import (
+	"log/slog"
+
+	"github.com/power-devops/perfstat"
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+type netinterfaceCollector struct {
+	logger     *slog.Logger
+	collisions *prometheus.Desc
+	ibytes     *prometheus.Desc
+	ipackets   *prometheus.Desc
+	obytes     *prometheus.Desc
+	opackets   *prometheus.Desc
+}
+
+const (
+	netinterfaceSubsystem = "netinterface"
+)
+
+func init() {
+	registerCollector("netinterface", defaultEnabled, NewNetinterfaceCollector)
+}
+
+func NewNetinterfaceCollector(logger *slog.Logger) (Collector, error) {
+	labels := []string{"interface"}
+	return &netinterfaceCollector{
+		logger: logger,
+		collisions: prometheus.NewDesc(
+			prometheus.BuildFQName(namespace, netinterfaceSubsystem, "collisions_total"),
+			"Total number of CSMA collisions on the interface.", labels, nil,
+		),
+		ibytes: prometheus.NewDesc(
+			prometheus.BuildFQName(namespace, netinterfaceSubsystem, "receive_bytes_total"),
+			"Total number of bytes received on the interface.", labels, nil,
+		),
+		ipackets: prometheus.NewDesc(
+			prometheus.BuildFQName(namespace, netinterfaceSubsystem, "receive_packets_total"),
+			"Total number of packets received on the interface.", labels, nil,
+		),
+		obytes: prometheus.NewDesc(
+			prometheus.BuildFQName(namespace, netinterfaceSubsystem, "transmit_bytes_total"),
+			"Total number of bytes transmitted on the interface.", labels, nil,
+		),
+		opackets: prometheus.NewDesc(
+			prometheus.BuildFQName(namespace, netinterfaceSubsystem, "transmit_packets_total"),
+			"Total number of packets transmitted on the interface.", labels, nil,
+		),
+	}, nil
+}
+
+func (c *netinterfaceCollector) Update(ch chan<- prometheus.Metric) error {
+	stats, err := perfstat.NetIfaceStat()
+	if err != nil {
+		return err
+	}
+
+	for _, stat := range stats {
+		iface := stat.Name
+
+		ch <- prometheus.MustNewConstMetric(c.collisions, prometheus.CounterValue, float64(stat.Collisions), iface)
+		ch <- prometheus.MustNewConstMetric(c.ibytes, prometheus.CounterValue, float64(stat.IBytes), iface)
+		ch <- prometheus.MustNewConstMetric(c.ipackets, prometheus.CounterValue, float64(stat.IPackets), iface)
+		ch <- prometheus.MustNewConstMetric(c.obytes, prometheus.CounterValue, float64(stat.OBytes), iface)
+		ch <- prometheus.MustNewConstMetric(c.opackets, prometheus.CounterValue, float64(stat.OPackets), iface)
+	}
+	return nil
+}