add EXCLUDE_SMART env var (#1392)

agent/smart.go

@@ -24,11 +24,12 @@ import (
 // SmartManager manages data collection for SMART devices
 type SmartManager struct {
 	sync.Mutex
-	SmartDataMap map[string]*smart.SmartData
-	SmartDevices []*DeviceInfo
-	refreshMutex sync.Mutex
-	lastScanTime time.Time
-	binPath      string
+	SmartDataMap    map[string]*smart.SmartData
+	SmartDevices    []*DeviceInfo
+	refreshMutex    sync.Mutex
+	lastScanTime    time.Time
+	binPath         string
+	excludedDevices map[string]struct{}
 }
 
 type scanOutput struct {
@@ -185,6 +186,7 @@ func (sm *SmartManager) ScanDevices(force bool) error {
 	}
 
 	finalDevices := mergeDeviceLists(currentDevices, scannedDevices, configuredDevices)
+	finalDevices = sm.filterExcludedDevices(finalDevices)
 	sm.updateSmartDevices(finalDevices)
 
 	if len(finalDevices) == 0 {
@@ -232,6 +234,47 @@ func (sm *SmartManager) parseConfiguredDevices(config string) ([]*DeviceInfo, er
 	return devices, nil
 }
 
+func (sm *SmartManager) refreshExcludedDevices() {
+	rawValue, _ := GetEnv("EXCLUDE_SMART")
+	sm.excludedDevices = make(map[string]struct{})
+
+	for entry := range strings.SplitSeq(rawValue, ",") {
+		device := strings.TrimSpace(entry)
+		if device == "" {
+			continue
+		}
+		sm.excludedDevices[device] = struct{}{}
+	}
+}
+
+func (sm *SmartManager) isExcludedDevice(deviceName string) bool {
+	_, exists := sm.excludedDevices[deviceName]
+	return exists
+}
+
+func (sm *SmartManager) filterExcludedDevices(devices []*DeviceInfo) []*DeviceInfo {
+	if devices == nil {
+		return []*DeviceInfo{}
+	}
+
+	excluded := sm.excludedDevices
+	if len(excluded) == 0 {
+		return devices
+	}
+
+	filtered := make([]*DeviceInfo, 0, len(devices))
+	for _, device := range devices {
+		if device == nil || device.Name == "" {
+			continue
+		}
+		if _, skip := excluded[device.Name]; skip {
+			continue
+		}
+		filtered = append(filtered, device)
+	}
+	return filtered
+}
+
 // detectSmartOutputType inspects sections that are unique to each smartctl
 // JSON schema (NVMe, ATA/SATA, SCSI) to determine which parser should be used
 // when the reported device type is ambiguous or missing.
@@ -378,6 +421,10 @@ func (sm *SmartManager) parseSmartOutput(deviceInfo *DeviceInfo, output []byte)
 // Uses -n standby to avoid waking up sleeping disks, but bypasses standby mode
 // for initial data collection when no cached data exists
 func (sm *SmartManager) CollectSmart(deviceInfo *DeviceInfo) error {
+	if deviceInfo != nil && sm.isExcludedDevice(deviceInfo.Name) {
+		return errNoValidSmartData
+	}
+
 	// slog.Info("collecting SMART data", "device", deviceInfo.Name, "type", deviceInfo.Type, "has_existing_data", sm.hasDataForDevice(deviceInfo.Name))
 
 	// Check if we have any existing data for this device
@@ -409,10 +456,10 @@ func (sm *SmartManager) CollectSmart(deviceInfo *DeviceInfo) error {
 
 	if !hasValidData {
 		if err != nil {
-			slog.Debug("smartctl failed", "device", deviceInfo.Name, "err", err)
+			slog.Info("smartctl failed", "device", deviceInfo.Name, "err", err)
 			return err
 		}
-		slog.Debug("no valid SMART data found", "device", deviceInfo.Name)
+		slog.Info("no valid SMART data found", "device", deviceInfo.Name)
 		return errNoValidSmartData
 	}
 
@@ -915,6 +962,7 @@ func NewSmartManager() (*SmartManager, error) {
 	sm := &SmartManager{
 		SmartDataMap: make(map[string]*smart.SmartData),
 	}
+	sm.refreshExcludedDevices()
 	path, err := sm.detectSmartctl()
 	if err != nil {
 		slog.Debug(err.Error())

agent/smart_test.go

@@ -588,3 +588,195 @@ func TestIsVirtualDeviceScsi(t *testing.T) {
 		})
 	}
 }
+
+func TestRefreshExcludedDevices(t *testing.T) {
+	tests := []struct {
+		name         string
+		envValue     string
+		expectedDevs map[string]struct{}
+	}{
+		{
+			name:         "empty env",
+			envValue:     "",
+			expectedDevs: map[string]struct{}{},
+		},
+		{
+			name:     "single device",
+			envValue: "/dev/sda",
+			expectedDevs: map[string]struct{}{
+				"/dev/sda": {},
+			},
+		},
+		{
+			name:     "multiple devices",
+			envValue: "/dev/sda,/dev/sdb,/dev/nvme0",
+			expectedDevs: map[string]struct{}{
+				"/dev/sda":   {},
+				"/dev/sdb":   {},
+				"/dev/nvme0": {},
+			},
+		},
+		{
+			name:     "devices with whitespace",
+			envValue: " /dev/sda , /dev/sdb ,  /dev/nvme0  ",
+			expectedDevs: map[string]struct{}{
+				"/dev/sda":   {},
+				"/dev/sdb":   {},
+				"/dev/nvme0": {},
+			},
+		},
+		{
+			name:     "duplicate devices",
+			envValue: "/dev/sda,/dev/sdb,/dev/sda",
+			expectedDevs: map[string]struct{}{
+				"/dev/sda": {},
+				"/dev/sdb": {},
+			},
+		},
+		{
+			name:     "empty entries and whitespace",
+			envValue: "/dev/sda,, /dev/sdb , , ",
+			expectedDevs: map[string]struct{}{
+				"/dev/sda": {},
+				"/dev/sdb": {},
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if tt.envValue != "" {
+				t.Setenv("EXCLUDE_SMART", tt.envValue)
+			} else {
+				// Ensure env var is not set for empty test
+				os.Unsetenv("EXCLUDE_SMART")
+			}
+
+			sm := &SmartManager{}
+			sm.refreshExcludedDevices()
+
+			assert.Equal(t, tt.expectedDevs, sm.excludedDevices)
+		})
+	}
+}
+
+func TestIsExcludedDevice(t *testing.T) {
+	sm := &SmartManager{
+		excludedDevices: map[string]struct{}{
+			"/dev/sda":   {},
+			"/dev/nvme0": {},
+		},
+	}
+
+	tests := []struct {
+		name         string
+		deviceName   string
+		expectedBool bool
+	}{
+		{"excluded device sda", "/dev/sda", true},
+		{"excluded device nvme0", "/dev/nvme0", true},
+		{"non-excluded device sdb", "/dev/sdb", false},
+		{"non-excluded device nvme1", "/dev/nvme1", false},
+		{"empty device name", "", false},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := sm.isExcludedDevice(tt.deviceName)
+			assert.Equal(t, tt.expectedBool, result)
+		})
+	}
+}
+
+func TestFilterExcludedDevices(t *testing.T) {
+	tests := []struct {
+		name           string
+		excludedDevs   map[string]struct{}
+		inputDevices   []*DeviceInfo
+		expectedDevs   []*DeviceInfo
+		expectedLength int
+	}{
+		{
+			name:         "no exclusions",
+			excludedDevs: map[string]struct{}{},
+			inputDevices: []*DeviceInfo{
+				{Name: "/dev/sda"},
+				{Name: "/dev/sdb"},
+				{Name: "/dev/nvme0"},
+			},
+			expectedDevs: []*DeviceInfo{
+				{Name: "/dev/sda"},
+				{Name: "/dev/sdb"},
+				{Name: "/dev/nvme0"},
+			},
+			expectedLength: 3,
+		},
+		{
+			name: "some devices excluded",
+			excludedDevs: map[string]struct{}{
+				"/dev/sda":   {},
+				"/dev/nvme0": {},
+			},
+			inputDevices: []*DeviceInfo{
+				{Name: "/dev/sda"},
+				{Name: "/dev/sdb"},
+				{Name: "/dev/nvme0"},
+				{Name: "/dev/nvme1"},
+			},
+			expectedDevs: []*DeviceInfo{
+				{Name: "/dev/sdb"},
+				{Name: "/dev/nvme1"},
+			},
+			expectedLength: 2,
+		},
+		{
+			name: "all devices excluded",
+			excludedDevs: map[string]struct{}{
+				"/dev/sda": {},
+				"/dev/sdb": {},
+			},
+			inputDevices: []*DeviceInfo{
+				{Name: "/dev/sda"},
+				{Name: "/dev/sdb"},
+			},
+			expectedDevs:   []*DeviceInfo{},
+			expectedLength: 0,
+		},
+		{
+			name:           "nil devices",
+			excludedDevs:   map[string]struct{}{},
+			inputDevices:   nil,
+			expectedDevs:   []*DeviceInfo{},
+			expectedLength: 0,
+		},
+		{
+			name: "filter nil and empty name devices",
+			excludedDevs: map[string]struct{}{
+				"/dev/sda": {},
+			},
+			inputDevices: []*DeviceInfo{
+				{Name: "/dev/sda"},
+				nil,
+				{Name: ""},
+				{Name: "/dev/sdb"},
+			},
+			expectedDevs: []*DeviceInfo{
+				{Name: "/dev/sdb"},
+			},
+			expectedLength: 1,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			sm := &SmartManager{
+				excludedDevices: tt.excludedDevs,
+			}
+
+			result := sm.filterExcludedDevices(tt.inputDevices)
+
+			assert.Len(t, result, tt.expectedLength)
+			assert.Equal(t, tt.expectedDevs, result)
+		})
+	}
+}