provide a mechanism to specify the absolute path to the smartctl bina…

…ry used by metrics collector.

- fixes #304

collector/pkg/collector/metrics.go

@@ -98,10 +98,10 @@ func (mc *MetricsCollector) Run() error {
 
 func (mc *MetricsCollector) Validate() error {
 	mc.logger.Infoln("Verifying required tools")
-	_, lookErr := exec.LookPath("smartctl")
+	_, lookErr := exec.LookPath(mc.config.GetString("commands.metrics_smartctl_bin"))
 
 	if lookErr != nil {
-		return errors.DependencyMissingError("smartctl is missing")
+		return errors.DependencyMissingError(fmt.Sprintf("%s binary is missing", mc.config.GetString("commands.metrics_smartctl_bin")))
 	}
 
 	return nil
@@ -124,7 +124,7 @@ func (mc *MetricsCollector) Collect(deviceWWN string, deviceName string, deviceT
 	}
 	args = append(args, fullDeviceName)
 
-	result, err := mc.shell.Command(mc.logger, "smartctl", args, "", os.Environ())
+	result, err := mc.shell.Command(mc.logger, mc.config.GetString("commands.metrics_smartctl_bin"), args, "", os.Environ())
 	resultBytes := []byte(result)
 	if err != nil {
 		if exitError, ok := err.(*exec.ExitError); ok {

collector/pkg/config/config.go

@@ -43,6 +43,7 @@ func (c *configuration) Init() error {
 
 	c.SetDefault("api.endpoint", "http://localhost:8080")
 
+	c.SetDefault("commands.metrics_smartctl_bin", "smartctl")
 	c.SetDefault("commands.metrics_scan_args", "--scan --json")
 	c.SetDefault("commands.metrics_info_args", "--info --json")
 	c.SetDefault("commands.metrics_smart_args", "--xall --json")

collector/pkg/detect/detect.go

@@ -29,7 +29,7 @@ type Detect struct {
 func (d *Detect) SmartctlScan() ([]models.Device, error) {
 	//we use smartctl to detect all the drives available.
 	args := strings.Split(d.Config.GetString("commands.metrics_scan_args"), " ")
-	detectedDeviceConnJson, err := d.Shell.Command(d.Logger, "smartctl", args, "", os.Environ())
+	detectedDeviceConnJson, err := d.Shell.Command(d.Logger, d.Config.GetString("commands.metrics_smartctl_bin"), args, "", os.Environ())
 	if err != nil {
 		d.Logger.Errorf("Error scanning for devices: %v", err)
 		return nil, err
@@ -60,7 +60,7 @@ func (d *Detect) SmartCtlInfo(device *models.Device) error {
 	}
 	args = append(args, fullDeviceName)
 
-	availableDeviceInfoJson, err := d.Shell.Command(d.Logger, "smartctl", args, "", os.Environ())
+	availableDeviceInfoJson, err := d.Shell.Command(d.Logger, d.Config.GetString("commands.metrics_smartctl_bin"), args, "", os.Environ())
 	if err != nil {
 		d.Logger.Errorf("Could not retrieve device information for %s: %v", device.DeviceName, err)
 		return err

example.collector.yaml

@@ -73,6 +73,7 @@ devices:
 
 # example to show how to override the smartctl command args globally
 #commands:
+#  metrics_smartctl_bin: 'smartctl' # change to provide custom `smartctl` binary path, eg. `/usr/sbin/smartctl`
 #  metrics_scan_args: '--scan --json' # used to detect devices
 #  metrics_info_args: '--info --json' # used to determine device unique ID & register device with Scrutiny
 #  metrics_smart_args: '--xall --json' # used to retrieve smart data for each device.