Merge pull request #263 from markusressel/feature/support-rpm-in-file…

…-fan-config

Feature/support rpm in file fan config

README.md

@@ -173,12 +173,17 @@ fans:
 fans:
   - id: file_fan
     file:
+      # Path to a file to set the PWM target for this fan
       path: /tmp/file_fan
+      # Path to a file to read the current RPM value of this fan
+      rpmPath: /tmp/file_fan_rpm
 ```
 
 ```shell
 > cat /tmp/file_fan
 255
+> cat /tmp/file_fan_rpm
+3421
 ```
 
 #### CMD

internal/configuration/fans.go

@@ -29,7 +29,8 @@ type HwMonFanConfig struct {
 }
 
 type FileFanConfig struct {
-	Path string `json:"path"`
+	Path    string `json:"path"`
+	RpmPath string `json:"rpmPath"`
 }
 
 type CmdFanConfig struct {

internal/fans/file.go

@@ -43,8 +43,25 @@ func (fan *FileFan) SetMaxPwm(pwm int, force bool) {
 	// not supported
 }
 
-func (fan *FileFan) GetRpm() (int, error) {
-	return 0, nil
+func (fan *FileFan) GetRpm() (result int, err error) {
+	filePath := fan.Config.File.RpmPath
+	// resolve home dir path
+	if strings.HasPrefix(filePath, "~") {
+		currentUser, err := user.Current()
+		if err != nil {
+			return result, err
+		}
+
+		filePath = filepath.Join(currentUser.HomeDir, filePath[1:])
+	}
+
+	integer, err := util.ReadIntFromFile(filePath)
+	if err != nil {
+		return 0, err
+	}
+	result = integer
+	fan.Pwm = result
+	return result, err
 }
 
 func (fan *FileFan) GetRpmAvg() float64 {
@@ -132,8 +149,9 @@ func (fan *FileFan) Supports(feature FeatureFlag) bool {
 	case FeatureControlMode:
 		return false
 	case FeatureRpmSensor:
-		// TODO: maybe we could support this in the future
-		return false
+		if len(fan.Config.File.RpmPath) > 0 {
+			return true
+		}
 	}
 	return false
 }