feat(inputs.nvidia_smi): Implement probing

plugins/inputs/nvidia_smi/nvidia_smi.go

@@ -31,8 +31,9 @@ type NvidiaSMI struct {
 	Timeout config.Duration `toml:"timeout"`
 	Log     telegraf.Logger `toml:"-"`
 
-	ignorePlugin bool
-	once         sync.Once
+	nvidiaSMIArgs []string
+	ignorePlugin  bool
+	once          sync.Once
 }
 
 func (*NvidiaSMI) SampleConfig() string {
@@ -53,14 +54,23 @@ func (smi *NvidiaSMI) Start(telegraf.Accumulator) error {
 
 func (*NvidiaSMI) Stop() {}
 
+func (smi *NvidiaSMI) Probe() error {
+	// Construct and execute metrics query
+	_, err := internal.CombinedOutputTimeout(exec.Command(smi.BinPath, smi.nvidiaSMIArgs...), time.Duration(smi.Timeout))
+	if err != nil {
+		return fmt.Errorf("calling %q failed: %w", smi.BinPath, err)
+	}
+	return nil
+}
+
 // Gather implements the telegraf interface
 func (smi *NvidiaSMI) Gather(acc telegraf.Accumulator) error {
 	if smi.ignorePlugin {
 		return nil
 	}
 
 	// Construct and execute metrics query
-	data, err := internal.CombinedOutputTimeout(exec.Command(smi.BinPath, "-q", "-x"), time.Duration(smi.Timeout))
+	data, err := internal.CombinedOutputTimeout(exec.Command(smi.BinPath, smi.nvidiaSMIArgs...), time.Duration(smi.Timeout))
 	if err != nil {
 		return fmt.Errorf("calling %q failed: %w", smi.BinPath, err)
 	}
@@ -119,8 +129,9 @@ func (smi *NvidiaSMI) parse(acc telegraf.Accumulator, data []byte) error {
 func init() {
 	inputs.Add("nvidia_smi", func() telegraf.Input {
 		return &NvidiaSMI{
-			BinPath: "/usr/bin/nvidia-smi",
-			Timeout: config.Duration(5 * time.Second),
+			BinPath:       "/usr/bin/nvidia-smi",
+			Timeout:       config.Duration(5 * time.Second),
+			nvidiaSMIArgs: []string{"-q", "-x"},
 		}
 	})
 }

plugins/inputs/nvidia_smi/nvidia_smi_test.go

@@ -4,16 +4,66 @@ import (
 	"errors"
 	"os"
 	"path/filepath"
+	"runtime"
 	"testing"
 	"time"
 
 	"github.com/influxdata/telegraf"
+	"github.com/influxdata/telegraf/config"
 	"github.com/influxdata/telegraf/internal"
 	"github.com/influxdata/telegraf/models"
 	"github.com/influxdata/telegraf/testutil"
 	"github.com/stretchr/testify/require"
 )
 
+func TestProbe(t *testing.T) {
+	var binPath string
+	var nvidiaSMIArgsPrefix []string
+	if runtime.GOOS == "windows" {
+		binPath = `C:\Windows\System32\WindowsPowerShell\v1.0\powershell.exe`
+		nvidiaSMIArgsPrefix = []string{"-Command"}
+	} else {
+		binPath = "/bin/bash"
+		nvidiaSMIArgsPrefix = []string{"-c"}
+	}
+
+	for _, tt := range []struct {
+		name        string
+		args        string
+		expectError bool
+	}{
+		{
+			name:        "probe success",
+			args:        "exit 0",
+			expectError: false,
+		},
+		{
+			name:        "probe error",
+			args:        "exit 1",
+			expectError: true,
+		},
+	} {
+		t.Run(tt.name, func(t *testing.T) {
+			plugin := &NvidiaSMI{
+				BinPath:       binPath,
+				nvidiaSMIArgs: append(nvidiaSMIArgsPrefix, tt.args),
+				Log:           &testutil.Logger{},
+				Timeout:       config.Duration(5 * time.Second),
+			}
+			model := models.NewRunningInput(plugin, &models.InputConfig{
+				Name:                 "nvidia_smi",
+				StartupErrorBehavior: "probe",
+			})
+			err := model.Probe()
+			if tt.expectError {
+				require.Error(t, err)
+			} else {
+				require.NoError(t, err)
+			}
+		})
+	}
+}
+
 func TestErrorBehaviorDefault(t *testing.T) {
 	// make sure we can't find nvidia-smi in $PATH somewhere
 	os.Unsetenv("PATH")