adding ability to write a log file with all output from collector. Executing commands will now log be logged (and when debug is enabled, their output's are also logged).

collector/cmd/collector-metrics/collector-metrics.go

@@ -5,6 +5,7 @@ import (
 	"github.com/analogj/scrutiny/collector/pkg/collector"
 	"github.com/analogj/scrutiny/webapp/backend/pkg/version"
 	"github.com/sirupsen/logrus"
+	"io"
 	"log"
 	"os"
 	"time"
@@ -85,6 +86,16 @@ OPTIONS:
 						logrus.SetLevel(logrus.InfoLevel)
 					}
 
+					if c.IsSet("log-file") {
+						logFile, err := os.OpenFile(c.String("log-file"), os.O_CREATE|os.O_WRONLY, 0644)
+						if err != nil {
+							logrus.Errorf("Failed to open log file %s for output: %s", c.String("log-file"), err)
+							return err
+						}
+						defer logFile.Close()
+						logrus.SetOutput(io.MultiWriter(os.Stderr, logFile))
+					}
+
 					metricCollector, err := collector.CreateMetricsCollector(
 						collectorLogger,
 						c.String("api-endpoint"),
@@ -105,6 +116,12 @@ OPTIONS:
 						EnvVars: []string{"SCRUTINY_API_ENDPOINT"},
 					},
 
+					&cli.StringFlag{
+						Name:  "log-file",
+						Usage: "Path to file for logging. Leave empty to use STDOUT",
+						Value: "",
+					},
+
 					&cli.BoolFlag{
 						Name:    "debug",
 						Usage:   "Enable debug logging",

collector/cmd/collector-selftest/collector-selftest.go

@@ -5,6 +5,7 @@ import (
 	"github.com/analogj/scrutiny/collector/pkg/collector"
 	"github.com/analogj/scrutiny/webapp/backend/pkg/version"
 	"github.com/sirupsen/logrus"
+	"io"
 	"log"
 	"os"
 	"time"
@@ -85,6 +86,16 @@ OPTIONS:
 						logrus.SetLevel(logrus.InfoLevel)
 					}
 
+					if c.IsSet("log-file") {
+						logFile, err := os.OpenFile(c.String("log-file"), os.O_CREATE|os.O_WRONLY, 0644)
+						if err != nil {
+							logrus.Errorf("Failed to open log file %s for output: %s", c.String("log-file"), err)
+							return err
+						}
+						defer logFile.Close()
+						logrus.SetOutput(io.MultiWriter(os.Stderr, logFile))
+					}
+
 					stCollector, err := collector.CreateSelfTestCollector(
 						collectorLogger,
 						c.String("api-endpoint"),
@@ -105,6 +116,12 @@ OPTIONS:
 						EnvVars: []string{"SCRUTINY_API_ENDPOINT"},
 					},
 
+					&cli.StringFlag{
+						Name:  "log-file",
+						Usage: "Path to file for logging. Leave empty to use STDOUT",
+						Value: "",
+					},
+
 					&cli.BoolFlag{
 						Name:    "debug",
 						Usage:   "Enable debug logging",

collector/pkg/collector/metrics.go

@@ -109,7 +109,7 @@ func (mc *MetricsCollector) Collect(wg *sync.WaitGroup, deviceWWN string, device
 	}
 	args = append(args, fmt.Sprintf("%s%s", detect.DevicePrefix(), deviceName))
 
-	result, err := common.ExecCmd("smartctl", args, "", os.Environ())
+	result, err := common.ExecCmd(mc.logger, "smartctl", args, "", os.Environ())
 	resultBytes := []byte(result)
 	if err != nil {
 		if exitError, ok := err.(*exec.ExitError); ok {

collector/pkg/common/exec.go

@@ -3,17 +3,19 @@ package common
 import (
 	"bytes"
 	"errors"
+	"github.com/sirupsen/logrus"
 	"io"
-	"os"
 	"os/exec"
 	"path"
+	"strings"
 )
 
-func ExecCmd(cmdName string, cmdArgs []string, workingDir string, environ []string) (string, error) {
+func ExecCmd(logger *logrus.Entry, cmdName string, cmdArgs []string, workingDir string, environ []string) (string, error) {
+	logger.Infof("Executing command: %s %s", cmdName, strings.Join(cmdArgs, " "))
 
 	cmd := exec.Command(cmdName, cmdArgs...)
 	var stdBuffer bytes.Buffer
-	mw := io.MultiWriter(os.Stdout, &stdBuffer)
+	mw := io.MultiWriter(logger.Logger.Out, &stdBuffer)
 
 	cmd.Stdout = mw
 	cmd.Stderr = mw

collector/pkg/common/exec_test.go

@@ -2,6 +2,7 @@ package common_test
 
 import (
 	"github.com/analogj/scrutiny/collector/pkg/common"
+	"github.com/sirupsen/logrus"
 	"github.com/stretchr/testify/require"
 	"os/exec"
 	"testing"
@@ -13,7 +14,7 @@ func TestExecCmd(t *testing.T) {
 	//setup
 
 	//test
-	result, err := common.ExecCmd("echo", []string{"hello world"}, "", nil)
+	result, err := common.ExecCmd(logrus.WithField("exec", "test"), "echo", []string{"hello world"}, "", nil)
 
 	//assert
 	require.NoError(t, err)
@@ -26,7 +27,7 @@ func TestExecCmd_Date(t *testing.T) {
 	//setup
 
 	//test
-	_, err := common.ExecCmd("date", []string{}, "", nil)
+	_, err := common.ExecCmd(logrus.WithField("exec", "test"), "date", []string{}, "", nil)
 
 	//assert
 	require.NoError(t, err)
@@ -56,7 +57,7 @@ func TestExecCmd_InvalidCommand(t *testing.T) {
 	//setup
 
 	//test
-	_, err := common.ExecCmd("invalid_binary", []string{}, "", nil)
+	_, err := common.ExecCmd(logrus.WithField("exec", "test"), "invalid_binary", []string{}, "", nil)
 
 	//assert
 	_, castOk := err.(*exec.ExitError)

collector/pkg/detect/detect.go

@@ -26,7 +26,7 @@ type Detect struct {
 // models.Device returned from this function only contain the minimum data for smartctl to execute: device type and device name (device file).
 func (d *Detect) smartctlScan() ([]models.Device, error) {
 	//we use smartctl to detect all the drives available.
-	detectedDeviceConnJson, err := common.ExecCmd("smartctl", []string{"--scan", "-j"}, "", os.Environ())
+	detectedDeviceConnJson, err := common.ExecCmd(d.Logger, "smartctl", []string{"--scan", "-j"}, "", os.Environ())
 	if err != nil {
 		d.Logger.Errorf("Error scanning for devices: %v", err)
 		return nil, err
@@ -64,7 +64,7 @@ func (d *Detect) smartCtlInfo(device *models.Device) error {
 	}
 	args = append(args, fmt.Sprintf("%s%s", DevicePrefix(), device.DeviceName))
 
-	availableDeviceInfoJson, err := common.ExecCmd("smartctl", args, "", os.Environ())
+	availableDeviceInfoJson, err := common.ExecCmd(d.Logger, "smartctl", args, "", os.Environ())
 	if err != nil {
 		d.Logger.Errorf("Could not retrieve device information for %s: %v", device.DeviceName, err)
 		return err
@@ -101,6 +101,7 @@ func (d *Detect) smartCtlInfo(device *models.Device) error {
 			Id:  availableDeviceInfo.Wwn.ID,
 		}
 		device.WWN = wwn.ToString()
+		d.Logger.Debugf("NAA: %d OUI: %d Id: %d => WWN: %s", wwn.Naa, wwn.Oui, wwn.Id, device.WWN)
 	} else {
 		d.Logger.Info("Using WWN Fallback")
 		d.wwnFallback(device)

collector/pkg/detect/devices_darwin.go

@@ -93,6 +93,7 @@ func (d *Detect) wwnFallback(detectedDevice *models.Device) {
 	if err == nil {
 		for _, disk := range block.Disks {
 			if disk.Name == detectedDevice.DeviceName {
+				d.Logger.Debugf("Found matching block device. WWN: %s", disk.WWN)
 				detectedDevice.WWN = disk.WWN
 				break
 			}
@@ -101,6 +102,7 @@ func (d *Detect) wwnFallback(detectedDevice *models.Device) {
 
 	//no WWN found, or could not open Block devices. Either way, fallback to serial number
 	if len(detectedDevice.WWN) == 0 {
+		d.Logger.Debugf("WWN is empty, falling back to serial number: %s", detectedDevice.SerialNumber)
 		detectedDevice.WWN = detectedDevice.SerialNumber
 	}
 }

collector/pkg/detect/devices_linux.go

@@ -30,6 +30,7 @@ func (d *Detect) wwnFallback(detectedDevice *models.Device) {
 	if err == nil {
 		for _, disk := range block.Disks {
 			if disk.Name == detectedDevice.DeviceName {
+				d.Logger.Debugf("Found matching block device. WWN: %s", disk.WWN)
 				detectedDevice.WWN = disk.WWN
 				break
 			}
@@ -38,6 +39,7 @@ func (d *Detect) wwnFallback(detectedDevice *models.Device) {
 
 	//no WWN found, or could not open Block devices. Either way, fallback to serial number
 	if len(detectedDevice.WWN) == 0 {
+		d.Logger.Debugf("WWN is empty, falling back to serial number: %s", detectedDevice.SerialNumber)
 		detectedDevice.WWN = detectedDevice.SerialNumber
 	}
 }