telegraf/plugins/inputs/opensmtpd/opensmtpd.go

135 lines
3.1 KiB
Go

package opensmtpd
import (
"bufio"
"bytes"
"fmt"
"os/exec"
"strconv"
"strings"
"time"
"github.com/influxdata/telegraf"
"github.com/influxdata/telegraf/filter"
"github.com/influxdata/telegraf/internal"
"github.com/influxdata/telegraf/plugins/inputs"
)
type runner func(cmdName string, Timeout internal.Duration, UseSudo bool) (*bytes.Buffer, error)
// Opensmtpd is used to store configuration values
type Opensmtpd struct {
Binary string
Timeout internal.Duration
UseSudo bool
filter filter.Filter
run runner
}
var defaultBinary = "/usr/sbin/smtpctl"
var defaultTimeout = internal.Duration{Duration: time.Second}
var sampleConfig = `
## If running as a restricted user you can prepend sudo for additional access:
#use_sudo = false
## The default location of the smtpctl binary can be overridden with:
binary = "/usr/sbin/smtpctl"
## The default timeout of 1000ms can be overridden with (in milliseconds):
timeout = 1000
`
func (s *Opensmtpd) Description() string {
return "A plugin to collect stats from Opensmtpd - a validating, recursive, and caching DNS resolver "
}
// SampleConfig displays configuration instructions
func (s *Opensmtpd) SampleConfig() string {
return sampleConfig
}
// Shell out to opensmtpd_stat and return the output
func opensmtpdRunner(cmdName string, Timeout internal.Duration, UseSudo bool) (*bytes.Buffer, error) {
cmdArgs := []string{"show", "stats"}
cmd := exec.Command(cmdName, cmdArgs...)
if UseSudo {
cmdArgs = append([]string{cmdName}, cmdArgs...)
cmd = exec.Command("sudo", cmdArgs...)
}
var out bytes.Buffer
cmd.Stdout = &out
err := internal.RunTimeout(cmd, Timeout.Duration)
if err != nil {
return &out, fmt.Errorf("error running smtpctl: %s", err)
}
return &out, nil
}
// Gather collects the configured stats from smtpctl and adds them to the
// Accumulator
//
// All the dots in stat name will replaced by underscores. Histogram statistics will not be collected.
func (s *Opensmtpd) Gather(acc telegraf.Accumulator) error {
// Always exclude uptime.human statistics
stat_excluded := []string{"uptime.human"}
filter_excluded, err := filter.Compile(stat_excluded)
if err != nil {
return err
}
out, err := s.run(s.Binary, s.Timeout, s.UseSudo)
if err != nil {
return fmt.Errorf("error gathering metrics: %s", err)
}
// Process values
fields := make(map[string]interface{})
scanner := bufio.NewScanner(out)
for scanner.Scan() {
cols := strings.Split(scanner.Text(), "=")
// Check split correctness
if len(cols) != 2 {
continue
}
stat := cols[0]
value := cols[1]
// Filter value
if filter_excluded.Match(stat) {
continue
}
field := strings.Replace(stat, ".", "_", -1)
fields[field], err = strconv.ParseFloat(value, 64)
if err != nil {
acc.AddError(fmt.Errorf("Expected a numerical value for %s = %v\n",
stat, value))
}
}
acc.AddFields("opensmtpd", fields, nil)
return nil
}
func init() {
inputs.Add("opensmtpd", func() telegraf.Input {
return &Opensmtpd{
run: opensmtpdRunner,
Binary: defaultBinary,
Timeout: defaultTimeout,
UseSudo: false,
}
})
}