Add ability to label inputs for logging (#6207)

plugins/inputs/exec/exec.go

@@ -3,7 +3,6 @@ package exec
 import (
 	"bytes"
 	"fmt"
-	"log"
 	"os/exec"
 	"path/filepath"
 	"runtime"
@@ -51,6 +50,7 @@ type Exec struct {
 	parser parsers.Parser
 
 	runner Runner
+	log    telegraf.Logger
 }
 
 func NewExec() *Exec {
@@ -161,7 +161,7 @@ func (e *Exec) ProcessCommand(command string, acc telegraf.Accumulator, wg *sync
 	if isNagios {
 		metrics, err = nagios.TryAddState(runErr, metrics)
 		if err != nil {
-			log.Printf("E! [inputs.exec] failed to add nagios state: %s", err)
+			e.log.Errorf("failed to add nagios state: %s", err)
 		}
 	}
 
@@ -229,6 +229,10 @@ func (e *Exec) Gather(acc telegraf.Accumulator) error {
 	return nil
 }
 
+func (e *Exec) Init() error {
+	return nil
+}
+
 func init() {
 	inputs.Add("exec", func() telegraf.Input {
 		return NewExec()

plugins/inputs/exec/exec_test.go

@@ -8,7 +8,6 @@ import (
 	"time"
 
 	"github.com/influxdata/telegraf/plugins/parsers"
-
 	"github.com/influxdata/telegraf/testutil"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
@@ -97,6 +96,7 @@ func TestExec(t *testing.T) {
 		MetricName: "exec",
 	})
 	e := &Exec{
+		log:      testutil.Logger{},
 		runner:   newRunnerMock([]byte(validJson), nil, nil),
 		Commands: []string{"testcommand arg1"},
 		parser:   parser,
@@ -126,6 +126,7 @@ func TestExecMalformed(t *testing.T) {
 		MetricName: "exec",
 	})
 	e := &Exec{
+		log:      testutil.Logger{},
 		runner:   newRunnerMock([]byte(malformedJson), nil, nil),
 		Commands: []string{"badcommand arg1"},
 		parser:   parser,
@@ -142,6 +143,7 @@ func TestCommandError(t *testing.T) {
 		MetricName: "exec",
 	})
 	e := &Exec{
+		log:      testutil.Logger{},
 		runner:   newRunnerMock(nil, nil, fmt.Errorf("exit status code 1")),
 		Commands: []string{"badcommand"},
 		parser:   parser,