mirror of
https://github.com/prometheus/node_exporter.git
synced 2024-09-20 08:07:31 -07:00
6eafa51fa8
* Implement commonalities and linux support for ARP collection * Add ARP collector to fixtures and run as part of e2e tests * Bubble up scanner errors * Use single return values where it makes sense * Add missing annotation * Move arp_common into arp_linux * Add license header to arp_linux.go * Address initial feedback * Use strings.Fields instead of strings.Split * Deal with scanner.Err() rather than throwing away errors * Check for scan errors in-line before interacting with the entries map * Don't interact with potentially empty text from scan * Check for scan errors outside the scan loop * Add comment about moving procfs parsing * Add more direct comment * Update initialism style to match go style guide * Put function args on the same line * Add TODO in front of comment about procfs extraction * Guard against strings.Fields returning an empty slice * Be more defensive about ARP table format and use upcase more broadly * Enable the ARP collector by default * Add ARP collector to the README * Remove 'entry'
103 lines
2.5 KiB
Go
103 lines
2.5 KiB
Go
// Copyright 2017 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.
|
|
|
|
// +build !noarp
|
|
|
|
package collector
|
|
|
|
import (
|
|
"bufio"
|
|
"fmt"
|
|
"io"
|
|
"os"
|
|
"strings"
|
|
|
|
"github.com/prometheus/client_golang/prometheus"
|
|
)
|
|
|
|
type arpCollector struct {
|
|
entries *prometheus.Desc
|
|
}
|
|
|
|
func init() {
|
|
Factories["arp"] = NewARPCollector
|
|
}
|
|
|
|
// NewARPCollector returns a new Collector exposing ARP stats.
|
|
func NewARPCollector() (Collector, error) {
|
|
return &arpCollector{
|
|
entries: prometheus.NewDesc(
|
|
prometheus.BuildFQName(Namespace, "arp", "entries"),
|
|
"ARP entries by device",
|
|
[]string{"device"}, nil,
|
|
),
|
|
}, nil
|
|
}
|
|
|
|
func getARPEntries() (map[string]uint32, error) {
|
|
file, err := os.Open(procFilePath("net/arp"))
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
defer file.Close()
|
|
|
|
entries, err := parseARPEntries(file)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
return entries, nil
|
|
}
|
|
|
|
// TODO: This should get extracted to the github.com/prometheus/procfs package
|
|
// to support more complete parsing of /proc/net/arp. Instead of adding
|
|
// more fields to this function's return values it should get moved and
|
|
// changed to support each field.
|
|
func parseARPEntries(data io.Reader) (map[string]uint32, error) {
|
|
scanner := bufio.NewScanner(data)
|
|
entries := make(map[string]uint32)
|
|
|
|
for scanner.Scan() {
|
|
columns := strings.Fields(scanner.Text())
|
|
|
|
if len(columns) < 6 {
|
|
return nil, fmt.Errorf("unexpected ARP table format")
|
|
}
|
|
|
|
if columns[0] != "IP" {
|
|
deviceIndex := len(columns) - 1
|
|
entries[columns[deviceIndex]]++
|
|
}
|
|
}
|
|
|
|
if err := scanner.Err(); err != nil {
|
|
return nil, fmt.Errorf("failed to parse ARP info: %s", err)
|
|
}
|
|
|
|
return entries, nil
|
|
}
|
|
|
|
func (c *arpCollector) Update(ch chan<- prometheus.Metric) error {
|
|
entries, err := getARPEntries()
|
|
if err != nil {
|
|
return fmt.Errorf("could not get ARP entries: %s", err)
|
|
}
|
|
|
|
for device, entryCount := range entries {
|
|
ch <- prometheus.MustNewConstMetric(
|
|
c.entries, prometheus.GaugeValue, float64(entryCount), device)
|
|
}
|
|
|
|
return nil
|
|
}
|