support blacklisting and wildcard matching in SENSORS env var (#650)

- Moved sensor related code to sensors.go
- Added SensorConfig struct
- Added newSensorConfig
- Added tests

beszel/internal/agent/sensors.go

@@ -0,0 +1,142 @@
+package agent
+
+import (
+	"beszel/internal/entities/system"
+	"context"
+	"log/slog"
+	"path"
+	"strconv"
+	"strings"
+
+	"github.com/shirou/gopsutil/v4/common"
+	"github.com/shirou/gopsutil/v4/sensors"
+)
+
+type SensorConfig struct {
+	context       context.Context
+	sensors       map[string]struct{}
+	primarySensor string
+	isBlacklist   bool
+	hasWildcards  bool
+}
+
+func (a *Agent) newSensorConfig() *SensorConfig {
+	primarySensor, _ := GetEnv("PRIMARY_SENSOR")
+	sysSensors, _ := GetEnv("SYS_SENSORS")
+	sensors, _ := GetEnv("SENSORS")
+
+	return a.newSensorConfigWithEnv(primarySensor, sysSensors, sensors)
+}
+
+// newSensorConfigWithEnv creates a SensorConfig with the provided environment variables
+func (a *Agent) newSensorConfigWithEnv(primarySensor, sysSensors, sensors string) *SensorConfig {
+	config := &SensorConfig{
+		context:       context.Background(),
+		primarySensor: primarySensor,
+	}
+
+	// Set sensors context (allows overriding sys location for sensors)
+	if sysSensors != "" {
+		slog.Info("SYS_SENSORS", "path", sysSensors)
+		config.context = context.WithValue(config.context,
+			common.EnvKey, common.EnvMap{common.HostSysEnvKey: sysSensors},
+		)
+	}
+
+	// Set sensors whitelist
+	if sensors != "" {
+		// handle blacklist
+		if strings.HasPrefix(sensors, "-") {
+			config.isBlacklist = true
+			sensors = sensors[1:]
+		}
+
+		config.sensors = make(map[string]struct{})
+		for sensor := range strings.SplitSeq(sensors, ",") {
+			sensor = strings.TrimSpace(sensor)
+			if sensor != "" {
+				config.sensors[sensor] = struct{}{}
+				if strings.Contains(sensor, "*") {
+					config.hasWildcards = true
+				}
+			}
+		}
+	}
+
+	return config
+}
+
+// updateTemperatures updates the agent with the latest sensor temperatures
+func (a *Agent) updateTemperatures(systemStats *system.Stats) {
+	// skip if sensors whitelist is set to empty string
+	if a.sensorConfig.sensors != nil && len(a.sensorConfig.sensors) == 0 {
+		slog.Debug("Skipping temperature collection")
+		return
+	}
+
+	// reset high temp
+	a.systemInfo.DashboardTemp = 0
+
+	// get sensor data
+	temps, _ := sensors.TemperaturesWithContext(a.sensorConfig.context)
+	slog.Debug("Temperature", "sensors", temps)
+
+	// return if no sensors
+	if len(temps) == 0 {
+		return
+	}
+
+	systemStats.Temperatures = make(map[string]float64, len(temps))
+	for i, sensor := range temps {
+		// skip if temperature is unreasonable
+		if sensor.Temperature <= 0 || sensor.Temperature >= 200 {
+			continue
+		}
+		sensorName := sensor.SensorKey
+		if _, ok := systemStats.Temperatures[sensorName]; ok {
+			// if key already exists, append int to key
+			sensorName = sensorName + "_" + strconv.Itoa(i)
+		}
+		// skip if not in whitelist or blacklist
+		if !isValidSensor(sensorName, a.sensorConfig) {
+			continue
+		}
+		// set dashboard temperature
+		if a.sensorConfig.primarySensor == "" {
+			a.systemInfo.DashboardTemp = max(a.systemInfo.DashboardTemp, sensor.Temperature)
+		} else if a.sensorConfig.primarySensor == sensorName {
+			a.systemInfo.DashboardTemp = sensor.Temperature
+		}
+		systemStats.Temperatures[sensorName] = twoDecimals(sensor.Temperature)
+	}
+}
+
+// isValidSensor checks if a sensor is valid based on the sensor name and the sensor config
+func isValidSensor(sensorName string, config *SensorConfig) bool {
+	// If no sensors configuration, everything is valid
+	if config.sensors == nil {
+		return true
+	}
+
+	// Exact match - return true if whitelist, false if blacklist
+	if _, exactMatch := config.sensors[sensorName]; exactMatch {
+		return !config.isBlacklist
+	}
+
+	// If no wildcards, return false if blacklist, true if whitelist
+	if !config.hasWildcards {
+		return config.isBlacklist
+	}
+
+	// Check for wildcard patterns
+	for pattern := range config.sensors {
+		if !strings.Contains(pattern, "*") {
+			continue
+		}
+		if match, _ := path.Match(pattern, sensorName); match {
+			return !config.isBlacklist
+		}
+	}
+
+	return config.isBlacklist
+}