fix: fail, if unknown collector is defined in enabled list

Signed-off-by: Jan-Otto Kröpke <mail@jkroepke.de>

exporter.go

@@ -188,7 +188,11 @@ func run() int {
 	}
 
 	enabledCollectorList := utils.ExpandEnabledCollectors(*enabledCollectors)
-	collectors.Enable(enabledCollectorList)
+	if err := collectors.Enable(enabledCollectorList); err != nil {
+		logger.Error(err.Error())
+
+		return 1
+	}
 
 	// Initialize collectors before loading
 	if err = collectors.Build(logger); err != nil {

pkg/collector/collector.go

@@ -168,12 +168,20 @@ func (c *MetricCollectors) SetPerfCounterQuery(logger *slog.Logger) error {
 }
 
 // Enable removes all collectors that not enabledCollectors.
-func (c *MetricCollectors) Enable(enabledCollectors []string) {
+func (c *MetricCollectors) Enable(enabledCollectors []string) error {
+	for _, name := range enabledCollectors {
+		if _, ok := c.Collectors[name]; !ok {
+			return fmt.Errorf("unknown collector %s", name)
+		}
+	}
+
 	for name := range c.Collectors {
 		if !slices.Contains(enabledCollectors, name) {
 			delete(c.Collectors, name)
 		}
 	}
+
+	return nil
 }
 
 // Build To be called by the exporter for collector initialization.