Node_Exporter/collector/netstat_linux.go
Tobias Schmidt 922e74d58f Remove unnecessarily named return variables
Named return variables should only be used to describe the returned type
further, e.g. `err error` doesn't add any new information and is just
stutter.
2017-02-28 16:04:25 -04:00

113 lines
3.0 KiB
Go

// Copyright 2015 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 !nonetstat
package collector
import (
"bufio"
"fmt"
"io"
"os"
"strconv"
"strings"
"github.com/prometheus/client_golang/prometheus"
)
const (
netStatsSubsystem = "netstat"
)
type netStatCollector struct{}
func init() {
Factories["netstat"] = NewNetStatCollector
}
// NewNetStatCollector takes and returns
// a new Collector exposing network stats.
func NewNetStatCollector() (Collector, error) {
return &netStatCollector{}, nil
}
func (c *netStatCollector) Update(ch chan<- prometheus.Metric) error {
netStats, err := getNetStats(procFilePath("net/netstat"))
if err != nil {
return fmt.Errorf("couldn't get netstats: %s", err)
}
snmpStats, err := getNetStats(procFilePath("net/snmp"))
if err != nil {
return fmt.Errorf("couldn't get SNMP stats: %s", err)
}
// Merge the results of snmpStats into netStats (collisions are possible, but
// we know that the keys are always unique for the given use case).
for k, v := range snmpStats {
netStats[k] = v
}
for protocol, protocolStats := range netStats {
for name, value := range protocolStats {
key := protocol + "_" + name
v, err := strconv.ParseFloat(value, 64)
if err != nil {
return fmt.Errorf("invalid value %s in netstats: %s", value, err)
}
ch <- prometheus.MustNewConstMetric(
prometheus.NewDesc(
prometheus.BuildFQName(Namespace, netStatsSubsystem, key),
fmt.Sprintf("Protocol %s statistic %s.", protocol, name),
nil, nil,
),
prometheus.UntypedValue, v,
)
}
}
return nil
}
func getNetStats(fileName string) (map[string]map[string]string, error) {
file, err := os.Open(fileName)
if err != nil {
return nil, err
}
defer file.Close()
return parseNetStats(file, fileName)
}
func parseNetStats(r io.Reader, fileName string) (map[string]map[string]string, error) {
var (
netStats = map[string]map[string]string{}
scanner = bufio.NewScanner(r)
)
for scanner.Scan() {
nameParts := strings.Split(scanner.Text(), " ")
scanner.Scan()
valueParts := strings.Split(scanner.Text(), " ")
// Remove trailing :.
protocol := nameParts[0][:len(nameParts[0])-1]
netStats[protocol] = map[string]string{}
if len(nameParts) != len(valueParts) {
return nil, fmt.Errorf("mismatch field count mismatch in %s: %s",
fileName, protocol)
}
for i := 1; i < len(nameParts); i++ {
netStats[protocol][nameParts[i]] = valueParts[i]
}
}
return netStats, scanner.Err()
}