fix: add missing metrics dropper

Author: matthiasemde

Companion/exporter/inventory_collector_storage.go

@@ -3,27 +3,43 @@ package exporter
 import (
 	"log"
 	"strconv"
+
+	"github.com/prometheus/client_golang/prometheus"
 )
 
 type StorageInventoryCollector struct {
-	endpoint string
+	endpoint       string
+	metricsDropper *MetricsDropper
 }
 
 func NewStorageInventoryCollector(endpoint string) *StorageInventoryCollector {
 	return &StorageInventoryCollector{
 		endpoint: endpoint,
+		metricsDropper: NewMetricsDropper(
+			StorageInventory,
+			StorageInventoryMax,
+		),
 	}
 }
 
 func (c *StorageInventoryCollector) Collect(frmAddress string, sessionName string) {
 	details := []ContainerDetail{}
 	err := retrieveData(frmAddress+c.endpoint, &details)
 	if err != nil {
+		c.metricsDropper.DropStaleMetricLabels()
 		log.Printf("error reading inventory statistics from FRM: %s\n", err)
 		return
 	}
 
 	for _, detail := range details {
+		c.metricsDropper.CacheFreshMetricLabel(prometheus.Labels{
+			"url":            frmAddress,
+			"session_name":   sessionName,
+			"container_name": detail.Name,
+			"x":              strconv.FormatFloat(detail.Location.X, 'f', -1, 64),
+			"y":              strconv.FormatFloat(detail.Location.Y, 'f', -1, 64),
+			"z":              strconv.FormatFloat(detail.Location.Z, 'f', -1, 64),
+		})
 		for _, item := range detail.Inventory {
 			StorageInventory.WithLabelValues(
 				item.Name,
@@ -36,6 +52,7 @@ func (c *StorageInventoryCollector) Collect(frmAddress string, sessionName strin
 			).Set(float64(item.Amount))
 		}
 	}
+	c.metricsDropper.DropStaleMetricLabels()
 }
 
 func (c *StorageInventoryCollector) DropCache() {}