Add exec plugin

This commit is contained in:
Alvaro Morales 2015-08-05 17:29:27 -07:00 committed by Cameron Sparr
parent 91f6c4b740
commit 090c0a60fa
3 changed files with 218 additions and 0 deletions

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@ -3,6 +3,7 @@ package all
import ( import (
_ "github.com/influxdb/telegraf/plugins/disque" _ "github.com/influxdb/telegraf/plugins/disque"
_ "github.com/influxdb/telegraf/plugins/elasticsearch" _ "github.com/influxdb/telegraf/plugins/elasticsearch"
_ "github.com/influxdb/telegraf/plugins/exec"
_ "github.com/influxdb/telegraf/plugins/haproxy" _ "github.com/influxdb/telegraf/plugins/haproxy"
_ "github.com/influxdb/telegraf/plugins/kafka_consumer" _ "github.com/influxdb/telegraf/plugins/kafka_consumer"
_ "github.com/influxdb/telegraf/plugins/lustre2" _ "github.com/influxdb/telegraf/plugins/lustre2"

129
plugins/exec/exec.go Normal file
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@ -0,0 +1,129 @@
package exec
import (
"bytes"
"encoding/json"
"fmt"
"github.com/bitly/go-simplejson"
"github.com/gonuts/go-shellquote"
"github.com/influxdb/telegraf/plugins"
"os/exec"
"sync"
)
const sampleConfig = `
# specify commands via an array of tables
[[exec.commands]]
# the command to run
command = "/usr/bin/mycollector --foo=bar"
# name of the command (used as a prefix for measurements)
name = "mycollector"
`
type Command struct {
Command string
Name string
}
type Exec struct {
Commands []*Command
runner Runner
}
type Runner interface {
Run(string, ...string) ([]byte, error)
}
type CommandRunner struct {
}
func NewExec() *Exec {
return &Exec{runner: CommandRunner{}}
}
func (c CommandRunner) Run(command string, args ...string) ([]byte, error) {
cmd := exec.Command(command, args...)
var out bytes.Buffer
cmd.Stdout = &out
if err := cmd.Run(); err != nil {
return nil, fmt.Errorf("exec: %s for command '%s'", err, command)
}
return out.Bytes(), nil
}
func (e *Exec) SampleConfig() string {
return sampleConfig
}
func (e *Exec) Description() string {
return "Read flattened metrics from one or more commands that output JSON to stdout"
}
func (e *Exec) Gather(acc plugins.Accumulator) error {
var wg sync.WaitGroup
var outerr error
for _, c := range e.Commands {
wg.Add(1)
go func(c *Command, acc plugins.Accumulator) {
defer wg.Done()
outerr = e.gatherCommand(c, acc)
}(c, acc)
}
wg.Wait()
return outerr
}
func (e *Exec) gatherCommand(c *Command, acc plugins.Accumulator) error {
words, err := shellquote.Split(c.Command)
if err != nil || len(words) == 0 {
return fmt.Errorf("exec: unable to parse command, %s", err)
}
out, err := e.runner.Run(words[0], words[1:]...)
if err != nil {
return err
}
jsonOut, err := simplejson.NewJson(out)
if err != nil {
return fmt.Errorf("exec: unable to parse output of '%s' as JSON, %s", c.Command, err)
}
return processResponse(acc, c.Name, map[string]string{}, jsonOut.Interface())
}
func processResponse(acc plugins.Accumulator, prefix string, tags map[string]string, v interface{}) error {
switch t := v.(type) {
case map[string]interface{}:
for k, v := range t {
if err := processResponse(acc, prefix+"_"+k, tags, v); err != nil {
return err
}
}
case json.Number:
value, err := v.(json.Number).Float64()
if err != nil {
return err
}
acc.Add(prefix, value, tags)
case bool, string, []interface{}:
// ignored types
return nil
default:
return fmt.Errorf("exec: got unexpected type %T with value %v (%s)", t, v, prefix)
}
return nil
}
func init() {
plugins.Add("exec", func() plugins.Plugin {
return NewExec()
})
}

88
plugins/exec/exec_test.go Normal file
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@ -0,0 +1,88 @@
package exec
import (
"fmt"
"github.com/influxdb/telegraf/testutil"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
"testing"
)
const validJson = `
{
"status": "green",
"num_processes": 82,
"cpu": {
"status": "red",
"used": 8234,
"free": 32
},
"percent": 0.81,
"users": [0, 1, 2, 3]
}`
const malformedJson = `
{
"status": "green",
`
type runnerMock struct {
out []byte
err error
}
func newRunnerMock(out []byte, err error) Runner {
return &runnerMock{out: out, err: err}
}
func (r runnerMock) Run(command string, args ...string) ([]byte, error) {
if r.err != nil {
return nil, r.err
}
return r.out, nil
}
func TestExec(t *testing.T) {
runner := newRunnerMock([]byte(validJson), nil)
command := Command{Command: "testcommand arg1", Name: "mycollector"}
e := &Exec{runner: runner, Commands: []*Command{&command}}
var acc testutil.Accumulator
err := e.Gather(&acc)
require.NoError(t, err)
checkFloat := []struct {
name string
value float64
}{
{"mycollector_num_processes", 82},
{"mycollector_cpu_used", 8234},
{"mycollector_cpu_free", 32},
{"mycollector_percent", 0.81},
}
for _, c := range checkFloat {
assert.True(t, acc.CheckValue(c.name, c.value))
}
assert.Equal(t, len(acc.Points), 4, "non-numeric measurements should be ignored")
}
func TestExecMalformed(t *testing.T) {
runner := newRunnerMock([]byte(malformedJson), nil)
command := Command{Command: "badcommand arg1", Name: "mycollector"}
e := &Exec{runner: runner, Commands: []*Command{&command}}
var acc testutil.Accumulator
err := e.Gather(&acc)
require.Error(t, err)
}
func TestCommandError(t *testing.T) {
runner := newRunnerMock(nil, fmt.Errorf("exit status code 1"))
command := Command{Command: "badcommand", Name: "mycollector"}
e := &Exec{runner: runner, Commands: []*Command{&command}}
var acc testutil.Accumulator
err := e.Gather(&acc)
require.Error(t, err)
}